Electrical Injuries in the Emergency Department (Continued on Page 13)

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November 2018 Electrical Injuries in the Volume 20, Number 11 Authors Emergency Department: Joshua Gentges, DO Associate Professor, Research Director, Department of Emergency Medicine, Oklahoma University School of Community Medicine, the An Evidence-Based Review University of Oklahoma, Tulsa, OK Christoph Schieche, MD Assistant Professor, Department of Emergency Medicine, Oklahoma Abstract University School of Community Medicine, the University of Oklahoma, Tulsa, OK

Electrical injuries can be caused by exposure to current from Peer Reviewers low-voltage and high-voltage sources as well as lightning Kelly P. O’Keefe, MD, FACEP strikes, and the circumstances of the exposure will dictate Professor of Clinical Sciences, Program Director, Emergency Medicine management strategies. Human tissues have varying resistance Residency, Florida State University College of Medicine, Sarasota Memorial Hospital, Sarasota, FL characteristics and susceptibility to damage, so injuries may Mark Silverberg, MD, FACEP be thermal, electrical, and/or mechanical, potentially caus- Associate Professor, Associate Residency Director, Kings County ing burns, thrombosis, tetany, falls, and blast injury. This issue Hospital, SUNY Downstate Department of Emergency Medicine, reviews the types of trauma seen with electrical injury and how Brooklyn, NY body systems can be affected by occult or delayed effects, and Prior to beginning this activity, see “Physician CME Information” the optimal evidence-based resuscitation and management on the back page. strategies associated with each. This issue is eligible for 4 Trauma CME credits.

Editor-In-Chief Daniel J. Egan, MD Shkelzen Hoxhaj, MD, MPH, MBA Alfred Sacchetti, MD, FACEP Pharmacy Residency, Maricopa Andy Jagoda, MD, FACEP Associate Professor, Vice Chair of Chief Medical Officer, Jackson Assistant Clinical Professor, Medical Center, Phoenix, AZ Education, Department of Emergency Memorial Hospital, Miami, FL Department of Emergency Medicine, Professor and Interim Chair, Joseph D. Toscano, MD Medicine, Columbia University Thomas Jefferson University, Department of Emergency Medicine; Eric Legome, MD Chief, Department of Emergency Vagelos College of Physicians and Philadelphia, PA Director, Center for Emergency Chair, Emergency Medicine, Mount Medicine, San Ramon Regional Medicine Education and Research, Surgeons, New York, NY Sinai West & Mount Sinai St. Luke's; Robert Schiller, MD Medical Center, San Ramon, CA Icahn School of Medicine at Mount Nicholas Genes, MD, PhD Vice Chair, Academic Affairs for Chair, Department of Family Medicine, Sinai, New York, NY Associate Professor, Department of Emergency Medicine, Mount Sinai Beth Israel Medical Center; Senior International Editors Emergency Medicine, Icahn School Health System, Icahn School of Faculty, Family Medicine and Peter Cameron, MD Associate Editor-In-Chief of Medicine at Mount Sinai, New Medicine at Mount Sinai, New York, NY Community Health, Icahn School of Academic Director, The Alfred Medicine at Mount Sinai, New York, NY Kaushal Shah, MD, FACEP York, NY Keith A. Marill, MD, MS Emergency and Trauma Centre, Associate Professor, Department of Scott Silvers, MD, FACEP Monash University, Melbourne, Michael A. Gibbs, MD, FACEP Associate Professor, Department Emergency Medicine, Icahn School Associate Professor of Emergency Australia Professor and Chair, Department of Emergency Medicine, Harvard of Medicine at Mount Sinai, New Medical School, Massachusetts Medicine, Chair of Facilities and of Emergency Medicine, Carolinas Andrea Duca, MD York, NY General Hospital, Boston, MA Planning, Mayo Clinic, Jacksonville, FL Medical Center, University of North Attending Emergency Physician, Editorial Board Carolina School of Medicine, Chapel Charles V. Pollack Jr., MA, MD, Corey M. Slovis, MD, FACP, FACEP Ospedale Papa Giovanni XXIII, Saadia Akhtar, MD, FACEP Hill, NC FACEP, FAAEM, FAHA, FESC Professor and Chair, Department Bergamo, Italy Professor & Senior Advisor for Associate Professor, Department of Steven A. Godwin, MD, FACEP of Emergency Medicine, Vanderbilt Suzanne Y.G. Peeters, MD Interdisciplinary Research and Emergency Medicine, Associate Dean Professor and Chair, Department University Medical Center, Nashville, TN Attending Emergency Physician, Clinical Trials, Department of for Graduate Medical Education, of Emergency Medicine, Assistant Flevo Teaching Hospital, Almere, Emergency Medicine, Sidney Kimmel Ron M. Walls, MD Program Director, Emergency Dean, Simulation Education, The Netherlands Medical College of Thomas Jefferson Professor and Chair, Department of Medicine Residency, Mount Sinai University of Florida COM- Emergency Medicine, Brigham and Beth Israel, New York, NY Jacksonville, Jacksonville, FL University, Philadelphia, PA Hugo Peralta, MD Women's Hospital, Harvard Medical Chair of Emergency Services, Michael S. Radeos, MD, MPH William J. Brady, MD Joseph Habboushe, MD MBA School, Boston, MA Hospital Italiano, Buenos Aires, Associate Professor of Emergency Professor of Emergency Medicine Assistant Professor of Emergency Argentina Medicine, Weill Medical College and Medicine; Chair, Medical Medicine, NYU/Langone and Critical Care Editors of Cornell University, New York; Dhanadol Rojanasarntikul, MD Emergency Response Committee; Bellevue Medical Centers, New York, Research Director, Department of William A. Knight IV, MD, FACEP, Attending Physician, Emergency Medical Director, Emergency NY; CEO, MD Aware LLC Emergency Medicine, New York FNCS Medicine, King Chulalongkorn Management, University of Virginia Gregory L. Henry, MD, FACEP Hospital Queens, Flushing, NY Associate Professor of Emergency Memorial Hospital, Thai Red Cross, Medical Center, Charlottesville, VA Clinical Professor, Department of Medicine and Neurosurgery, Medical Thailand; Faculty of Medicine, Ali S. Raja, MD, MBA, MPH Emergency Medicine, University Director, EM Advanced Practice Chulalongkorn University, Thailand Calvin A. Brown III, MD Executive Vice Chair, Emergency Director of Physician Compliance, of Michigan Medical School; CEO, Provider Program; Associate Medical Medicine, Massachusetts General Stephen H. Thomas, MD, MPH Credentialing and Urgent Care Medical Practice Risk Assessment, Director, Neuroscience ICU, University Hospital; Associate Professor of Professor & Chair, Emergency Services, Department of Emergency Inc., Ann Arbor, MI of Cincinnati, Cincinnati, OH Emergency Medicine and Radiology, Medicine, Hamad Medical Corp., Medicine, Brigham and Women's John M. Howell, MD, FACEP Harvard Medical School, Boston, MA Scott D. Weingart, MD, FCCM Weill Cornell Medical College, Qatar; Hospital, Boston, MA Clinical Professor of Emergency Professor of Emergency Medicine; Emergency Physician-in-Chief, Medicine, George Washington Robert L. Rogers, MD, FACEP, Chief, EM Critical Care, Stony Brook Peter DeBlieux, MD Hamad General Hospital, University, Washington, DC; Director FAAEM, FACP Medicine, Stony Brook, NY Professor of Clinical Medicine, Doha, Qatar of Academic Affairs, Best Practices, Assistant Professor of Emergency Louisiana State University School of Inc, Inova Fairfax Hospital, Falls Medicine, The University of Research Editors Edin Zelihic, MD Medicine; Chief Experience Officer, Church, VA Maryland School of Medicine, Head, Department of Emergency Aimee Mishler, PharmD, BCPS University Medical Center, New Baltimore, MD Medicine, Leopoldina Hospital, Emergency Medicine Pharmacist, Orleans, LA Schweinfurt, Germany Program Director, PGY2 EM Case Presentations making recognition challenging, and history is sometimes difficult to obtain. Management of these You arrive to work at the regional burn center’s ED, and a cases has evolved over time, especially in recom- nurse pulls you into resuscitation bay 1. Paramedics have mendations for cardiac monitoring and ear, nose, presented with a thirtysomething man in cardiac arrest. and throat (ENT) care for pediatric oral electrical He had been helping his daughter build a curious device burns. This issue of Emergency Medicine Practice called a Jacob’s ladder—a homemade machine that creates reviews the current evidence for diagnosis and man- an electrical arc. His presenting rhythm was asystole but agement of electrical injuries, focusing on recogni- by the time of his arrival in the ED, he is in ventricular tion of life-threatening and occult injury. fibrillation. You wonder if his cardiac arrest is related to the device, and what your next best step is... Critical Appraisal of the Literature As you start work, you wonder where your end-of- shift colleague is. The question is answered when the A literature search was performed using Ovid and curtain for bay 2 is pulled back and you see her intubating MEDLINE® for the period between 1966 to 2018, a young man. She tells you he arrived by ambulance for with the terms emergency, electrical injury, electrocu- “burn care.” He fell 12 feet to the ground after his mop tion, and lightning. This provided a list of 477 articles pole touched a power line above the semi-trailer he was that was narrowed to 88 after initial review. Some cleaning. There are minor burns to his hands and chest resources were identified from article reference wall, but more worrisome is the pink fluid draining from lists, and some articles with redundant or outdated his ears and nose. As you assess the patient, you wonder information were excluded. The experimental evi- how best to prioritize the patient's workup... dence pertaining to electrical injuries is limited, and Just as you sit down, a nurse tells you that he has most clinical practice is based on expert opinion and put another electrical injury patient in bay 3; the patient observational studies. The most recent statistical in- is a 24-year-old man who accidently touched an electrical formation was obtained directly from United States socket and was thrown backwards to the floor. He didn't governmental survey and statistical data or from hit his head, but he complains of feeling “tingly” all over occupational and advocacy organizations. Practice and slightly nauseated. His vital signs are: blood pressure, guidelines are limited and based on expert opinion, 130/ 86 mm Hg; respiratory rate, 16 breaths/min; heart case studies, and observational studies. rate, 68 beats/min; and oxygen saturation, 100% on room air. He has no past medical history and a normal physical Etiology and Pathophysiology exam. The nurse asks if he should get an ECG and send a troponin; you wonder...what is best practice? Electricity is the movement of electrons down a gradient, from high to low potential. The current (I), Introduction measured in amperes (A), can be thought of as the total amount of electrons moving down the gradient Patients with electrical injury pose unique diagnostic per unit of time. Voltage (V) is the potential differ- and therapeutic challenges that emergency clinicians ence between the top and the bottom of the gradient, must not miss. Each year, approximately 10,000 such as between 2 ends of a wire or the entrance and patients present to United States emergency depart- exit wounds on a patient with an electrical injury. ments (EDs) with electrical burns or electric shock,1 Resistance (R) is the obstruction of electrical flow with fatalities declining from around 1000 per year by a material, and is important in electrical injury in the early 2000s to 565 in 2015,2 likely because of because current will tend to follow the path of least improved occupational protections.3 An estimated resistance, providing important clues about under- 4% of burn center admissions are due to electrical lying injury in particular types of electrical current burns.4 Most electrical injuries are due to household exposure. Current is directly proportional to voltage or occupational exposures.1,2 There is a trimodal and inversely proportional to resistance. Current can distribution of patients with electrical injuries; be alternating current (AC, switching between posi- young children are affected most often by household tive and negative flow) or direct current (DC, current current, adolescent males by high-risk behavior flowing continuously in 1 direction). (eg, playing near high-voltage current sources), and Because most electrical injuries result from adult males by occupational exposure.5-8 Lightning grasping an electrical source with the hands, tetany strikes are a subset of electrical injuries with unique causes the inability to release the contact source,3,8 features. In the United States, between 25 and 50 and respiratory paralysis may occur if there is suf- people die each year from lightning strikes.2 ficient current.9 Tetany can cause muscular contrac- Electrical injuries can affect every organ system tions powerful enough to cause orthopedic trauma, and can cause thermal, electrophysiological, trau- rhabdomyolysis, and muscle necrosis,10 and longer matic, and metabolic derangement. Patients may contact due to tetany means more tissue damage. resemble ordinary cardiac, trauma, or burn victims, The current required to prevent release of an electri-

Copyright © 2018 EB Medicine. All rights reserved. 2 Reprints: www.ebmedicine.net/empissues cal source because of muscle contraction is termed and subsequent tissue damage. Electrically sensitive the “let-go” threshold. (See Table 1.) Humans are tissues, such as nerve and muscle, are more sensitive typically able to perceive AC that is between 0.2 mA to AC.16 AC is found in lower-voltage applications and 2 mA.11 such as standard home and office wiring, but is also found in high-voltage applications, including high- Varied Tissue Resistance to Electricity voltage transmission lines. DC does not cause as Damage to tissues from electricity is largely— much sensation, has a higher let-go threshold, and though not completely—due to thermal injury and is requires more amperage to cause ventricular fibril- dependent on tissue resistance, voltage and amper- lation.17 DC is found in batteries, car and computer age, the type of circuit (direct or alternating current), electrical systems, some high-voltage transmission and contact duration.12 Nonthermal injury can be lines, and capacitors. due to electrical injury to nerve tissue, muscle or Voltage affects tissue in 2 ways. The first is bone damage from tetanic contractions, and electro- through electroporation, which is the direct damage lyte derangement.10 of cell membranes by high voltage.18 The second is Human tissues differ in their resistance to by overcoming the resistance of body tissues and electrical energy.12 The skin offers varying resis- intervening objects (clothes, water, machinery, etc). tance levels, depending on its condition: dry skin Very high voltages can even arc through nominally offers the most resistance and can protect underly- high-resistance air, causing burns without direct ing structures, but as skin absorbs more energy, its contact with the electrical source.19 The resistance resistance breaks down. Wet or lacerated skin offers of dry skin is significantly reduced when current much less resistance to electricity and allows current voltage exceeds 500 V. The fact that higher voltages to flow to deeper structures.9,12 Nerve tissue typi- reduce resistance to current and can increase injury cally has the least resistance to electrical energy, and leads to the useful (if arbitrary) heuristic of low-volt- may be damaged even when current is of low voltage versus high-voltage exposure. (See Table 2.) The age and no cutaneous or musculoskeletal manifesta- United States Department of Energy's recommended tions are present.11,13 Blood and vascular tissue have cutoff standard for low voltage is 600 V, 20 a standard low resistance to current, and muscle and viscera with which the authors of this review concur. have slightly higher resistance. Bone and fat have Patients with electrical injuries often have a the highest resistance to current. The consequence complicated presentation, with multisystem inju- of higher resistance is that more energy is lost to ries. Injury occurs from energy deposition in tissues higher-resistance tissue in the form of heat, causing in the form of heat (thermal injury), electrical dam- coagulation necrosis and burns both in the high- age to electrically sensitive tissue, and mechanical resistance tissues and in surrounding tissues. This trauma that is often due to falls or forceful muscle poses a challenge for the emergency clinician, as the contractions.20 Mechanical trauma can occur even extent of surface burns may not reveal the extent of in patients with low-voltage exposure that would burns to visceral and deep muscular tissues, espe- ostensibly cause minimal injury, as patients may cially when the skin of the patient is wet or there is respond to an electric shock by jerking away and skin breakdown, lacerations, and/or abrasions. then suffer subsequent trauma due to loss of balance and falling. Relating Voltage and Current to Tissue Injury Both the type of current (AC or DC) and the volt- Table 2. Effects of Low-Voltage Versus High- age of the electrical source have important effects Voltage Electrical Shock on the amount of energy transmitted to the body Low-Voltage Shock Effects High-Voltage Shock Effects (< 600 Volts) (600+ Volts) Table 1. Physical Effects at Selected Superficial burns Deep and occult burns Currents14,15 No late arrhythmia Case reports of late arrhythmia Usually alternating current Either alternating current or Current (mA) Response direct current 0.2-2 “Electrical” sensation Rhabdomyolysis uncommon Rhabdomyolysis common 1-2+ Painful shock Secondary trauma less common Secondary trauma from falls and 3-5 Let-go threshold for children tetanic muscle contractions 6-10 Minimum let-go threshold for adults Contact is prolonged (unable to Contact can be brief (thrown 22 99% of adults cannot let go let go) from voltage source) 10-20 Tetany (contact area) Cardiac arrest from ventricular Cardiac arrest from ventricular fibrillation fibrillation; direct damage to 20-50 Tetany (respiratory muscles) myocardium, causing asystole; 50-100 Ventricular fibrillation and coronary artery thrombosis www.ebmedicine.net www.ebmedicine.net

November 2018 • www.ebmedicine.net 3 Copyright © 2018 EB Medicine. All rights reserved. Differential Diagnosis Figure 1. Flash Burns in a High-Voltage Injury Most patients with electrical injury can be diagnosed by careful history. In cases where the patient is unable to give history, physical clues such as characteristic burns can give clinical suspicion for electric shock. Unexplained cardiac arrest in a patient in an open area during a storm or near high-voltage lines should put electric shock or lightning strike high in the differential. In some patients, the electrical injury will be minimal, and morbidity will be caused by secondary effects such as trauma from a fall.

Cutaneous Injury Most electrical injuries present as burns to the skin.19,21,22 Injuries from low-voltage exposures are more likely to be superficial burns at the entry and Although the burns may appear to be superficial, these findings should 11,23 24 exit sites, not significant cutaneous injuries. prompt a search for deep tissue injuries. However, if exposure time is prolonged, tissue dam- Image courtesy of Oklahoma University School of Community Medicine. age can become more extensive, causing deep burns that may require skin grafts or debridement. High- voltage exposures are more serious, causing larger, Figure 2. High-Voltage Burn deeper burns that are more likely to require extensive skin grafting, debridement, or amputation.19 In high-voltage exposures, skin can be burned deeply enough to compromise the underlying vascular sup- ply, especially when the burns are circumferential, necessitating escharotomy. High voltage can overcome the typically high resistance of dry skin tissue and travel through subcutaneous tissue and deeper structures and cause deep, extensive burns underneath areas of relatively uninjured skin. Emergency clinicians must be aware of this possibility and consider the electrical pathway through the body of patients who experience high-voltage exposure. Flash burns can be caused by the arcing of high-voltage electrical energy through the air across large areas of skin.19 (See Figure 1.) The direct conversion of electrical energy to thermal energy can be so vigorous that tissue can be heated sufficiently to cause explosive loss of skin, subcutaneous tissue, or muscle. (See Figure 2.)

Musculoskeletal Injury Patients commonly suffer injured muscles, tendons, and bones after electrical exposure.19,22,23 Injury mechanism is by either thermal or mechanical means. Thermal injury leads to muscle breakdown, rhabdomyolysis, myonecrosis, and edema that can become severe, and compartment syndrome can occur. Myonecrosis can be a late finding, occurring days after the initial injury.21 When voltage and current are sufficient to overcome the very high resistance of bone, large amounts of heat are deposited in the bone and periosteal tissues.14 This leads to Evidence of a flash burn, with charring and ragged, deep burns on the osteonecrosis and periosteal burns, with subsequent- third and fourth fingers, characteristic of entrance or exit wounds. ly poor bone healing. Mechanical injury is caused Image courtesy of Oklahoma University School of Community Medicine. by forceful muscular contraction as a result of the

Copyright © 2018 EB Medicine. All rights reserved. 4 Reprints: www.ebmedicine.net/empissues current and by falls due to syncope or aversion from exposure can cause pneumothorax or pulmonary the electrical exposure. In 2 retrospective analyses, contusion. Late findings include pulmonary ef- 11% of patients with high-voltage exposures had fusions, pneumonitis, or pneumonia.12 These are traumatic injuries.19,22 Traumatic injuries included usually seen within a week of exposure. Another po- fractures, dislocations, and significant muscular in- tential late finding is pulmonary embolus from deep juries. High-voltage injuries have an especially high venous thrombosis (DVT) after injury. The electrical surgical injury rate, with debridement, fasciotomy, resistance of lung tissue is relatively higher than and amputations for limb ischemia or widespread other thoracic structures,14 which may account for tissue damage being common.19,21-23 Fractures can the decreased incidence of direct pulmonary injury, also occur in low-voltage exposures, although this is as more current will flow through the surrounding less common.25 Spinal trauma can occur from hyper- lower-resistance structures. extension caused by forceful muscular contraction.16 Vascular Injury Cardiovascular Injury Blood vessels are highly conductive and are com- Electrical injury to the cardiovascular system is a monly injured by electrical burns,9,14 leading to feared, though rare, complication of both high- and localized vascular injury or thrombosis. Coagula- low-voltage electrical shock. The pathway of the tion necrosis and thrombosis in vascular structures electric shock is predictive of potential myocardial causes damage to both the vessel and surrounding injury or arrhythmia, and large surface burns and a tissues. Smaller vessels have lower flow rates and vertical pathway through the torso between the en- are at higher risk for developing thrombosis. This trance and exit points indicate higher risk of injury small-vessel injury can lead to decreased tissue to the heart.26 Common electrocardiogram (ECG) perfusion in muscles and visceral organs, with the abnormalities from electrical exposure include atrio- consequence of tissue necrosis, edema, and compart- ventricular block, bundle branch blocks, atrial fibril- ment syndrome. Arterial thrombosis can cause acute lation, QT prolongation, and ventricular arrhyth- limb ischemia.35 mias.27,28 In the worst-case scenario, electrical energy Patients with severe electrical burns who are that travels through the heart can induce ventricular hospitalized have increased iatrogenic risk of DVT, tachycardia or ventricular fibrillation; this is usually especially if they are immobilized or undergo multi- seen immediately after exposure. ple surgeries.36 The total incidence of DVT in burned Case reports of delayed-onset cardiac dysrhyth- patients is around 1%, but in hospitalized patients, mias have led some emergency clinicians to initiate this rises to as much as 23%.36-38 prolonged cardiac monitoring in patients with an electrical injury. 29 There have been no randomized Neurological Injury clinical trials addressing this issue, but several well- Nerve tissue is highly conductive, and neurologi- designed observational studies have demonstrated cal injury after electric shock is common. This can no evidence of late-onset arrhythmia necessitating be due to direct thermal damage to nerve tissue or any intervention.23,30-32 Hansen et al studied a Dutch from electroporation, which is especially damag- cohort from 1994 to 2011, with 11,462 patients with ing to nerve cells that are dependent on establishing both high- and low-voltage electrical exposure, and electrolyte gradients for proper functioning. The most noted no patients with late-onset arrhythmia related common neurological complaint after electric shock is to exposure. Patients with ventricular tachycardia or loss of consciousness. fibrillation in this cohort had these arrhythmias on In a survey study of a cohort of both high- and arrival, although this cohort was young and healthy low-voltage exposures, over 80% of patients had de- and the study may not have perfect applicability to layed neurological complaints, including numbness, other populations.31 weakness, paresthesia, and difficulty concentrating.39 Patients can have thermal and electrical injury A prospective cohort study established a 28% inci- to the myocardium, causing myocardial infarction, dence of neurologic injury in a primarily low-volt- pericardial injury, and heart failure.29 ST-segment age exposure group,40 similar to the 25% found in a elevation myocardial infarction is well-described study by Arnoldo et al.19 Injury pattern is important, in the literature, is often associated with normal as many patients complain of paresthesia or perma- coronary angiography, and is likely due to coronary nent numbness at the entrance and exit sites, and a artery vasospasm.26,33,34 pathway that traverses the spinal cord (ie, from one limb to another) puts a patient at risk for spinal cord Respiratory Injury lesions. The amount of current and the voltage are Respiratory failure secondary to electric shock relatively less predictive of the types and severity of is usually due to underlying cardiac arrest. Tho- neurologic injury.40,41 Immediate symptoms often re- racic tetany can cause paralysis of the respiratory solve and have a better prognosis than late sequelae. muscles.9 Trauma from falls secondary to electrical Patients may also develop secondary neurological

November 2018 • www.ebmedicine.net 5 Copyright © 2018 EB Medicine. All rights reserved. injury from hypoxia and subsequent ischemia after port time to a hospital is likely to be prolonged. The cardiac arrest or spinal cord injury due to spinal success rate of cardiopulmonary resuscitation (CPR) artery vasospasm. is much higher in this patient population,53,54 as they There is a higher incidence of spinal cord injury are less likely than the typical cardiac arrest patient in high-voltage trauma.42-44 These are most often to have underlying comorbid conditions. reported as transverse lesions with posterior cord Trauma is common in high-voltage injuries. Cer- syndrome. Depression, chronic pain, anxiety, mood vical spine immobilization is necessary in any pa- swings, and cognitive difficulty are all commonly tient with a significant injury or a loss of conscious- described.40-43 ness. Intravenous (IV) access should be established, and isotonic IV fluids given as a 10 to 20 mL/kg Other Injuries bolus in hypotensive patients or patients with evi- Any organ system can be impacted by electric dence of burns. Patients with syncope or a decreased shock. Visceral injury is rare but must be considered, level of consciousness should receive an ECG and especially in high-voltage injuries with a pathway continuous cardiac monitoring. Disposition can be through the thorax.45 This can include pancreatic challenging, especially if the local burn center and and renal injury, although bowel perforation is most the local trauma center are in different hospitals. In common. Renal injury is also possible from myone- general, trauma takes priority over burns, so pa- crosis and rhabdomyolysis.11 High-voltage exposure tients with evidence of significant trauma should is associated with the development of cataracts, be transported to a trauma center.51 Patients who macular injury, and retinal detachment.46 Hearing are exposed to high voltage and are obtunded or loss, tinnitus, and vertigo due to inner ear dysfunc- unconscious should be sent to a trauma center, as tion are well described.47 These symptoms can be traumatic injuries are more common in this group. due to tympanic membrane perforation, ossicle injury, or cranial nerve damage and can be transient Emergency Department Evaluation or permanent. Symptoms (especially cataracts) can occur years after initial injury. Electrical injuries, especially high-voltage injuries, Injury to the oral commissure in pediatric are potentially multisystem trauma combined with patients is a concerning electrical injury, and its burns. Patients should receive a primary and sec- treatment is controversial. Children may chew on ondary survey following both ACLS and Advanced an electrical cord, causing burns to the tongue and Trauma Life Support® (ATLS) guidelines. Airway the palate. The depth of the injury may not be im- management is a priority, especially if head or neck mediately apparent, and vascular injury to the labial burns are present.50 Remember that the severity of artery or surrounding structures can lead to immedi- the burn may not be apparent from the initial skin ate or delayed severe bleeding, with possible airway examination. obstruction and massive hemorrhage. There is no Patients must be completely disrobed, and rings consensus on early versus late ENT intervention, and other jewelry should be removed. IV fluid resus- oral splinting, or disposition management.48,49 citation should proceed with the goal of maintain- ing diuresis at 1 to 1.5 mL/kg/hr. The amount of Prehospital Care IV fluid required in severe burns can be very large and cannot be determined by the Parkland formula A prehospital call for electric shock requires a or other body surface area estimations.19,52 Patients high-priority response and may be a challenging who have experienced high-voltage exposure should scenario.50,51 The voltage source at the scene may have an ECG and cardiac monitoring, although in still be live, placing prehospital personnel at risk. It low-voltage injuries with no syncope and a normal is paramount that first responders be protected from initial ECG, monitoring is not required. (See Table electrical exposure. If the patient is still connected 3.) Well-appearing, minimally injured patients to the electrical source, they cannot be approached exposed to low voltages are much less likely to have until it is certain that the power source has been severe trauma or burns, but should still have a full removed. In high-voltage injuries (power lines, evaluation, as occult injuries are possible.25 transformers, etc) the responders should verify with local electrical authorities that the power source has been shut off. Table 3. Indications for Cardiac Monitoring Patients in cardiac arrest are managed follow- After Electrical Injury24,27-29 ing standard Advanced Cardiovascular Life Support (ACLS) guidelines.52 If facial or neck burns are pres- • Any high-voltage exposure (600+ V) ent or if there is any evidence of airway compromise, • Syncope there is a high risk for airway loss, and these pa- • Any abnormal rhythm or electrocardiographic evidence of ischemia tients should be intubated early, especially if trans- • Chest pain

Copyright © 2018 EB Medicine. All rights reserved. 6 Reprints: www.ebmedicine.net/empissues History Patients with a low-voltage exposure, no arrhythmia History must include evaluation of the type of in the field, no syncope, and no chest pain do not current (AC/DC), voltage, physical environment require further cardiac monitoring. There is evidence (outdoors/indoors, weather, risk of falling), and suggesting that high-voltage exposures without underlying medical conditions, especially cardiac initial ECG changes may not require monitoring, conditions predisposing to arrhythmia. Note that but it is limited, and current clinical consensus does a voltage source thought to be low voltage (eg, not support omitting cardiac monitoring in these 24,27,30 household current) may, in fact, be high voltage.20 patients. Duration of monitoring varied in 30,32 An example of this would be an exposure from a studies, but ranged from 6 to 24 hours. Our rec- discharging capacitor in a high-energy household ommendation is for overnight monitoring, or at least appliance, such as a television. Patients may not be 8 hours of monitoring. able to provide history, so discussion with emergency medical services (EMS) personnel or bystand- Laboratory Testing ers is important. EMS personnel should be asked There is no evidence that routine laboratory test- about the prehospital care undertaken, including ing in patients with low-voltage, minor cutaneous resuscitative measures. As with all trauma patients, burns is helpful. For serious injuries (eg, those with emergency clinicians should take a medical history entrance and exit wounds or history of ECG abnor- and document allergies and medications and tetanus malities or dysrhythmia), obtain a complete blood immunization status. cell count, complete metabolic panel, and urinalysis. Creatine kinase (CK) and CK-MB (creatine kinase- Physical Examination muscle/brain) testing can be helpful. CK helps Patients require a thorough and methodical physi- assess for rhabdomyolysis. A CK-MB > 80 ng/mL is 55 cal examination after the initial evaluation. Burns predictive of limb amputation. Cardiac troponin should be carefully assessed, noting size and loca- is not helpful in most cases, although this was not 56 tion. After disrobing, all skin surfaces must be exam- assessed in the case of cardiac arrest. Coagulation ined for occult injuries. Assess visual fields for clues studies should be obtained if there is concern for to retinal injury or potential neurologic injury, assess intra-abdominal pathology or if the patient may re- hearing, and perform a complete ENT examination, quire surgery. Obtain a pregnancy test in all women including otoscopic and funduscopic examination. of childbearing years. Extremities should be examined for bony tenderness, joint tenderness, and restriction in range of Diagnostic Imaging motion. Decisions for imaging are driven by history and The path taken through the body by the cur- physical examination. Perform a FAST (focused as- rent must be considered. Important clues about sessment with sonography in trauma) examination the path of the current can be found by noting the to screen for intra-abdominal pathology. In general, entrance and exit wounds (burns or open injuries), maintain a high index of suspicion for traumatic in- (see Figure 2, page 4), but remember that there may jury in high-voltage exposures or lightning strikes, have been other electrical pathways causing injury or if the electrical injury resulted in a fall. Patients as well.16 A careful primary and secondary survey is who have altered mental status, an abnormal neu- essential. rological examination, or are unconscious should Perform serial examinations on the extremities have computed tomographic (CT) scan of the brain to evaluate for vascular compromise and compart- and cervical spine, abdomen, and possibly chest. ment syndrome. In high-voltage injuries and light- Obtain radiographic evaluation of any painful or ning strikes, the risk for traumatic injury is high, deformed bony areas. Maintain a high index of sus- and evaluation of the chest, abdomen, and pelvis picion for pelvic injuries and shoulder dislocations. for trauma should be performed. This will include Patients who complain of severe pain or inability to a search for signs of a basilar skull fracture (post move the shoulder should have a CT scan if x-rays auricular ecchymosis, hemotympanum, and clear are negative, as posterior dislocations are difficult nasal drainage), cervical injury, and pneumothorax to see on plain x-ray.57 Complaints of chest pain or pulmonary contusion. or abdominal pain should prompt further radiographic evaluation, with CT scanning preferred, Diagnostic Studies to evaluate for injury. Extremity ultrasound with arterial and venous Doppler is useful to identify Electrocardiogram the possibility of thrombosis. Perform an ECG on all patients presenting with a history of electric shock. There are reports of myocardial infarction, arrhythmia, and other ECG abnormalities after both low- and high-voltage exposure.

November 2018 • www.ebmedicine.net 7 Copyright © 2018 EB Medicine. All rights reserved. Treatment and it is controversial in intubated patients.60,61 Nosocomial infection is a risk, and severely Minor Injuries burned patients (ie, any patient with more than Electrical injuries can be divided into minor and ma- minor superficial burns) should be cared for using contact precautions, including sterile gowns, jor injuries. Minor injuries are small cutaneous burns 62 caused by low-voltage exposure. These patients gloves, and face masks. Patients are at high risk should have a normal ECG and no history of synco- for limb ischemia and compartment syndrome. pe, chest pain, or orthopedic injury, with no airway The emergency clinician must recognize these involvement. These patients may require no inter- complications and involve general, vascular, and vention other than analgesia, return precautions, orthopedic surgery early in the patient's manage- and follow-up with their primary care provider or ment for possible surgical intervention. There the burn center. is no consensus on early surgical exploration of affected limbs in severe electrical injury, with most 63 Major Electrical Injuries authors recommending a conservative approach. Initial treatment of severe electrical injury should be directed toward establishing airway patency Special Populations and supporting breathing and circulation. Patients with any type of burn to the face or neck are at Pediatric Patients high risk for airway edema.58 A prospective study Although children are more likely to sustain low- found a higher risk of a difficult airway in patients voltage injuries, they have higher relative morbidity with delayed intubation, especially if intubation because of their thinner skin, smaller body area, and was delayed until the patient arrived at the burn lower resistance to electrical energy. Young children center.59 This finding should prompt the emergen- (aged < 5 years) are most likely to present with oro- cy clinician to establish a definitive airway prior facial burns. There is up to 24% risk of labial artery to transfer if there are burns to the face and neck, bleeding64 and primary tooth damage, and although as high-voltage burns tend to involve structures there is no consensus on timing of surgical interven- deeper than observed on initial examination. Sev- tion or necessity of oral splinting, the emergency eral backup airway options should be at the ready clinician should obtain early ENT intervention and for these patients. Options include video-assisted strongly consider admission or transfer for observa- laryngoscopy, bougie assistance, and fiberoptic tion. Labial artery bleeding is often delayed, and can equipment. A surgical airway setup (cricothyroto- be seen up to 2 weeks after initial presentation.48,49 my) should be available at the bedside. Maintain Older children are more likely to be adolescent cervical spine immobilization in obtunded or boys engaging in risk-taking behaviors. They have a unconscious patients requiring intubation. Estab- higher incidence of high-voltage injuries and upper lish IV access and give isotonic fluids to maintain extremity injuries, often requiring fasciotomy or skin urine output at 1 to 1.5 mL/kg/hr. Obtain an ECG grafting.6,8 and place the patient on cardiac monitoring. Pain control is difficult in all severely burned Pregnant Patients patients, and it can be especially problematic in The literature on electrical injury in pregnant patients with electrical injuries. Opioid analgesia patients consists mostly of case reports and a few is preferred, and large doses may be required. A cohort studies. In a small prospective study, low- short-acting opioid such as fentanyl (1 mcg/kg voltage exposure did not change fetal outcomes.65 IV), given as a continuous infusion, may allow Case reports describe fetal arrhythmia, fetal ischemic for better pain control and is more easily titrat- brain injury, and fetal demise.66,67 Patients whose able. Hypotension and respiratory depression are pregnancies are past the age of fetal viability (usu- concerns, and it may be necessary to intubate a ally 20 weeks, though local practice can vary) should patient with high-voltage injury to more easily have fetal monitoring after experiencing electric control pain. shock. An ultrasound should be obtained if it has not Burned areas should be cleaned and dressed yet been done during the pregnancy, and a 2-week with an antibiotic dressing. Update tetanus im- follow-up ultrasound is also recommended.67 munization as indicated. For more information on managing thermal burns, see the February 2018 Patients With Taser (Electrical Control issue of Emergency Medicine Practice, “Emergency Device) Injuries Department Management of Patients With Ther- The electrical control device weapon, known by the mal Burns” at www.ebmedicine.net/Burns. brand name of Taser, is a device that typically shoots It is unclear whether prophylactic antibiotics 2 barbed projectiles into the body in order to subdue are beneficial. Their use is not currently recom- an individual. (See Figure 3, page 9.) Devices vary mended, based on a review of the burn literature, by model, but there may be an initial 50,000 V shock,

Copyright © 2018 EB Medicine. All rights reserved. 8 Reprints: www.ebmedicine.net/empissues with multiple subsequent shocks.68 There are case the electrical energy from the strike to stay on the reports of ventricular fibrillation and of traumatic external skin surface, called the flashover effect. In injuries from the metal barbs.69 There is contro- addition, the rapid expansion of air causes a concus- versy surrounding the Taser literature, with some sive blast. These unique features lead to unusual researchers calling into question the possibility of injury patterns, and patients can be thrown to the Taser-induced arrhythmia, suggesting that it is more ground or into objects. Lightning-strike injuries can likely to be due to underlying structural disease or also occur inside a building, with current traveling “excited delirium.”70-73 Some patients report cogni- through electrical wiring or through plumbing to tive abnormalities immediately after exposure; it cause electric shock to persons inside a structure.76,77 is not known whether there is a risk for permanent EMS personnel should be aware of the potential for cognitive difficulty.74 further strikes when responding to a possible light- Most Taser injuries are direct traumatic effects ning strike and take measures to protect themselves, from the Taser darts and indirect trauma from falls moving the patient to a safer environment as soon as or physical interactions with police.68,75 These inju- it is possible and safe to do so.51 ries are usually minor, although fractures and trau- In lightning injury, burns are common, and can matic brain injuries have been reported. Injuries to be arc burns, flash burns to the surface, or deeper sensitive body parts such as eyes and testicles have burns, although the short exposure time tends to been reported. Pneumothorax and injury to a gravid limit total burn energy. Lichtenberg figures (a fine patient are also considerations. Patients should be branching rash that may resemble bare tree branch- approached as standard assault/trauma patients, es) are pathognomonic for lightning injury. (See with the addition of an ECG to assess for arrhyth- Figure 4.) These skin changes are superficial, do not mia, bearing in mind that some patients who present require treatment, and fade within weeks. Ocular to the ED in police custody are under the influence injury (including retinal detachment and cataracts) of drugs, alcohol, or have mental illness. Complaints and otologic injury are common,76,78 and tympanic of chest pain or shortness of breath should be taken membrane rupture occurs in up to two-thirds of seriously, as Taser injury (increased sympathetic tone cases.75 Ophthalmologic consultation should be from the stressful encounter) and drug effects could all contribute to these symptoms. Management of a cardiac arrest in the setting of a Taser injury is Figure 4. Lichtenberg Figures unchanged from standard ACLS protocols.

Lightning Strikes Lightning strikes present differently from other electrical injuries. Voltage is in the millions, and amperage in the thousands, but exposure time is measured in milliseconds, so total energy transfer is limited.74,76 Because most lightning strikes occur in open areas outside and it is often raining during the exposure, highly conductive wet skin may cause

Figure 3. An Electrical Control Device Used by Law Enforcement

Police-issue X26 TASER. This device delivers very high voltages for very short periods of time. The total energy imparted is 0.07J/pulse, Lichtenberg figures: cutaneous manifestations of phone electrocution with a maximum of 85 pulses. from lightning. The Journal of Plastic, Reconstructive & Aesthetic Image used by permission of Creative Commons Attribution-Share Surgery. Volume 61, Issue 1. Aljay L. Mahajan, Ruchika Rajan, alike 3.0 Unported license. Author: Junglecat. Padraic J. Regan. © 2008, with permission from Elsevier.

Patient presents to the emergency department with electrical injury

• Resuscitate as necessary • Perform primary and secondary survey • Obtain history and physical examination • Perform ECG for all patients • Estimate current voltage exposure (Class III)

Low voltage (< 600 V) High voltage (600+ V)

Abnormal ECG, syncope, traumatic • Initiate telemetry YES injuries, or any nonminor burns? • Start IV access and IV fluids • Order CBC, CMP, UA, CK NO • Apply burn dressings as needed

• Discharge home with return Is patient at a regional burn center? precautions for compartment syndrome, chest pain, or syncope • Caution patient about late sequelae YES NO (chronic pain, neuropsychiatric effects) (Class II)

• Consult burn surgeon • Transfer to regional burn center • Involve other consultants as • Ensure adequate IV fluid necessary (orthopedic, ear/nose/ resuscitation (1-1.5 mL/kg/hr of urine throat, cardiology) output) • Continue fluid resuscitation and • Offer analgesia (short-acting opioid analgesia preferred) Abbreviations: CBC, complete blood cell count; CK, • Perform serial neurovascular • Consider airway protection, especially creatine kinase; CMP, comprehensive metabolic examinations with facial burns panel; ECG, electrocardiogram; IV, intravenous; (Class II) (Class II) UA, urinalysis.

Class of Evidence Definitions

Each action in the clinical pathways section of Emergency Medicine Practice receives a score based on the following definitions.

Class I Class II Class III Indeterminate • Always acceptable, safe • Safe, acceptable • May be acceptable • Continuing area of research • Definitely useful • Probably useful • Possibly useful • No recommendations until further • Proven in both efficacy and effectiveness • Considered optional or alternative treat- research Level of Evidence: ments Level of Evidence: • Generally higher levels of evidence Level of Evidence: • One or more large prospective studies • Nonrandomized or retrospective studies: Level of Evidence: • Evidence not available are present (with rare exceptions) historic, cohort, or case control studies • Generally lower or intermediate levels of • Higher studies in progress • High-quality meta-analyses • Less robust randomized controlled trials evidence • Results inconsistent, contradictory • Study results consistently positive and • Results consistently positive • Case series, animal studies, • Results not compelling compelling consensus panels • Occasionally positive results

This clinical pathway is intended to supplement, rather than substitute for, professional judgment and may be changed depending upon a patient’s individual needs. Failure to comply with this pathway does not represent a breach of the standard of care. Copyright © 2018 EB Medicine. www.ebmedicine.net. No part of this publication may be reproduced in any format without written consent of EB Medicine.

Copyright © 2018 EB Medicine. All rights reserved. 10 Reprints: www.ebmedicine.net/empissues obtained as soon as practical. Cardiac complications tient’s primary care provider or with the regional include sudden death, cardiac contusion, or coro- burn center. nary vasospasm.77,79 Resuscitation is more likely to High-voltage injuries require admission to be successful in these patients than in typical cardiac a burn center. Regional burn centers will have a arrest patients.50,52 burn surgeon on call at all times, and the burn Lightning strikes are especially problematic surgeon must be involved in care of all admit- from a neurologic standpoint. Central nervous ted burn patients. Orthopedic surgery, ENT, and system dysfunction can be immediate or delayed, cardiology should be consulted according to the and can include ischemic stroke, spinal cord injury, patient’s injuries. For emergency clinicians not at or keraunoparalysis, a temporary condition that a burn center, transfer should be arranged to the mimics spinal cord injury.41-44,80-85 These patients can burn center after initial stabilization. The transfer- develop cerebral salt wasting syndrome, transient or ring physician must be aware of the transport time permanent stroke symptoms, and peripheral nerve and possible complications that may develop dur- lesions. They are also at risk for trauma-related ing transport, including airway loss and develop- neurologic morbidity, eg, spinal cord fractures and ment of limb ischemia. Pretransfer stabilization skull fractures.80,82-84 Pinpoint cerebral hemorrhage, may therefore involve intubation, fasciotomy, or ischemia, and infarction have been described, and escharotomy. Transport should be performed by injury may be detected only by magnetic resonance ACLS-certified paramedics, and preferably by imaging (MRI).84 Any organ system can be involved. critical care-trained personnel such as air medical Myoglobinuria and rhabdomyolysis are uncom- transport crews.50,51 Ensure that crews are aware mon.77,86 Vasospasm can mimic stroke, myocardial of treatment guidelines for fluid resuscitation, infarction, and bowel ischemia, or cause signs of evaluation of neurovascular status, and analgesia. compartment syndrome, though these findings are Trauma takes precedence over burn – patients usually self-limited. The American College of Sur- with severe traumatic injuries will require transfer geons recommends that these patients be transferred to a trauma center first. to a burn center for further evaluation and treatment, as they have very complicated presentations Summary and multiple system involvement.52,87 • All patients with an electrical injury should Controversies receive an ECG. Low-voltage exposures with a normal ECG and no evidence of syncope do not Antibiotic prophylaxis is controversial in the burn need further hematological testing or cardiac literature.60,61,88 Randomized controlled trials are monitoring. rare and suffer from methodological problems.61 • Injuries may be more than skin deep; evaluate Some trials showed benefit of antibiotic prophylaxis for trauma to muscle, bone, viscera, and brain. in the perioperative period and in mechanically • The skin may be relatively spared, but patients ventilated patients. The most recent meta-analysis can have subcutaneous burns, tissue edema, and of trials did not support routine antibiotic prophy- compartment syndrome under undamaged skin. laxis in inpatient burn victims. Emergency clinicians • Cardiac resuscitation should proceed according should consult with the burn surgeon about antibi- to ACLS guidelines, and is likely to be successful. otic prophylaxis. • In partial- or full-thickness electrical burns, There is suggestive, but not definitive, evidence isotonic IV fluids should be administered to that cardiac monitoring is not necessary for any maintain urine output at 1 to 1.5 mL/kg/hr. patients without ECG changes, regardless of volt- • Patients with low-voltage exposures with mini- age level,32 but no well-designed prospective trials mal apparent injury and a normal ECG can go were found. The most recent literature continues to home with good return precautions. All high- recommend cardiac monitoring for patients with a voltage exposures and lightning strikes should high-voltage injury or initial ECG abnormalities.30,32 be transferred to a burn or trauma center for further evaluation. Disposition • Burns from lightning strikes are likely to be superficial; however, the extremely high voltage Low-voltage injuries in patients with normal ECG, in lightning strikes can cause neurologic compli- no syncope or arrhythmia, and minimal inju- cations, and secondary trauma from concussive ries can be discharged home without prolonged force is a concern. Self-limited vasospasm can cardiac rhythm monitoring. They should be given mimic neurologic, cardiac, and gastrointestinal return precautions for chest pain, palpitations, ischemia, as well as compartment syndrome. syncope, and compartment syndrome. Follow-up • Patients who are discharged must be given should be explicitly arranged with either the pa- return precautions for neurological symptoms,

November 2018 • www.ebmedicine.net 11 Copyright © 2018 EB Medicine. All rights reserved. compartment syndrome, and syncope. They and the cardiac monitor showed occasional premature must be warned about potential late sequelae, ventricular contractions. Though these patients generally such as cataracts, neurological and autonomic do well without deterioration, best practice continues to dysfunction, visceral injury, and vascular injury. advocate for 12 to 24 hours of cardiac monitoring. You admitted him to the telemetry unit; there was no indication Case Conclusions for antiarrhythmic treatment. He remained asymptomatic for 24 hours, at which time he was discharged. The Jacob’s ladder patient clearly experienced a high-volt- The pink fluid draining from the nose and ears of your age electric shock. His vital signs were stable on arrival, patient who fell off the semi-trailer was caused by the patient having sustained a basilar skull fracture from the fall. Risk Management Pitfalls for Electrical Injuries in the Emergency Department (Continued on page 13)

1. “I sent the patient with a low-voltage minor 4. “A patient was brought in by the police last electrical burn home and told her she was fine night. He was ‘minding his own business’ and (she was!). She came back to the ED 2 weeks somehow ended up Tasered. He said it hurt to later and is angry because she developed dizzi- lift his arm. I x-rayed his humerus and elbow, ness and paresthesia in her fingers.” both negative, with normal pulses and sensa- Electrical injuries have a high incidence of tion, so I discharged him into police custody. delayed neurological sequelae,41 with studies Unfortunately, they brought him back 2 days noting between 25% and 80% of patients later… he ended up being diagnosed with a reporting neurological complaints after electric scapular fracture.” shock.39,40 It is important to give specific, Taser (or other electroshock weapon) injuries detailed discharge instructions, including return are on the rise in the United States, and 1 out precautions for numbness, dizziness, weakness, of 9 police-related injuries presenting to United and mental status changes. States EDs are caused by these devices.76,77 The majority of injuries are minor abrasions, 2. “I admitted an electrician with upper extrem- lacerations, and contusions. Forceful muscle ity and facial burns and airway management contraction can cause fractures, including who was injured working on a high-voltage spinous process fractures and scapular injuries. line. The orthopedic surgeon called and is Cardiac electrical capture with subsequent angry because he has an open foot fracture. ventricular fibrillation and asystole is a rare The ED was busy; I can’t take every single complication.78 patient’s boots off.” High-voltage injuries have a high incidence of 5. “I work at the regional burn center. EMS orthopedic injuries, and electrical current at brought in a 45-year-old lineman who touched entrance and exit sites can be sufficient to cause a high-voltage line. The shock entered his left open injuries. Remember to completely undress arm and exited his right leg. I admitted him to patients so you do not miss injuries on your burn ICU, gave IV fluids for his open inju- primary and secondary survey. ries, but I didn’t have time to recheck him. He needed multiple doses of pain medicine. While 3. “The man was found lying in the grass, un- he was holding in the ED his arm became tight, conscious. His CT scan and labs were normal. shiny, and pale…he had a delay in his emer- He seemed confused on re-evaluation, so I gent fasciotomy.” admitted him for altered mental status, which Burn patients with significant orthopedic I thought was probably drug-related. The next injuries are at high risk for compartment day I got a call from the hospitalist; appar- syndrome, and electrical burns are at even ently the ENT said he has extensive inner and higher risk because of the full-thickness middle ear damage and is now deaf.” nature of many of these injuries. Frequent Patients found unconscious for no apparent neurovascular checks are a must, especially reason in an open area should have lightning in the first 12 hours. Your ED should have a strike in the differential. (Lightning can strike protocol for neurovascular checks for these even when it is not raining, during an event patients, and progressive or uncontrolled pain called a “dry” thunderstorm.) The concussive should prompt further investigation. force of the strike can be sufficient to rupture tympanic membranes and cause inner ear damage.47 A thorough ENT examination is necessary.

Copyright © 2018 EB Medicine. All rights reserved. 12 Reprints: www.ebmedicine.net/empissues The burns on his hand and chest most likely represented the electrical socket has a low-voltage injury. His exam was entrance and exit of the electrical discharge and the fall pos- normal, as was his ECG. There was no indication for do- sibly due to a transient dysrhythmia. Fortunately, his vital ing a troponin nor any indication for cardiac monitoring. signs were stable and there was no evidence of myocardial You discussed with the patient the possible side effects damage. Instead, the leaking cerebrospinal fluid was the from a low-voltage injury, including persisting numbness biggest concern, and you were reminded of the importance and tingling, which generally resolves. The patient was of a careful secondary survey in patients with electrical in- discharged with instructions to return for any cardiac juries. The patient was admitted to the neurosurgical ICU, symptoms; you called him 24 hours later and all symp- remained stable, and had an uneventful recovery. toms had resolved. Your third patient who sustained a shock from an Risk Management Pitfalls for Electrical Injuries in the Emergency Department (Continued from page 12)

6. “The 2-year-old had a small burn on his face the lips as risk factors for intubation. Maintain a after playing with an electrical cord. There was high index of suspicion for airway involvement no airway involvement, and I sent him home to and consider fiberoptic laryngoscopy or early follow up with a burn specialist. Then 24 hours intubation in electrical burns involving the face later, he came back bleeding profusely from or neck. the mouth…that airway was touch-and-go.” Oral burns in children who chewed on an 9. “We saw a patient who grabbed a low-voltage electrical cord have up to 24% incidence line with both hands. She said that her left arm of bleeding from the labial artery. Proper hurt, but there was no sign of trauma, x-ray initial management is controversial, but was negative, and her ECG was completely ENT consultation should be obtained, and if normal. That night she returned, and her arm the patient goes home, you must give strict was cold and pale.” discharge instructions and set patient/family There is a risk of acute arterial and venous expectations for the possibility of bleeding.48,49 thrombosis in patients injured by electric current. This is hypothesized to be due to both thermal 7. “This patient was transferred to our burn damage and electrical damage to the intima of center for evaluation of his high-voltage burns the vessel. In a patient with unexplained pain in after he was cleared by the trauma center. We a limb after electrical injury, you must document admitted him to the burn floor, where he had neurovascular status and serial examinations. If a seizure and then became obtunded. It turned pain persists, further workup is necessary, which out he had a basilar skull fracture. The surgeon may include ultrasound, CT angiography, or asked me if I had looked behind his ears.’” formal angiography. Initial traumatic injuries may not be apparent in high-voltage exposures, and you should 10. “This high-voltage injury patient came to the do a thorough traumatic evaluation in these ED with 10% total body surface area burns. I patients. In this case, early recognition of a skull followed the Parkland formula for fluids, but fracture (which may reveal the Battle sign, with she stayed hypotensive and, during her hos- bruising behind the ears) could have prompted pital course, developed acute renal failure. I seizure prophylaxis, neurosurgical consultation, thought that formula was solid for taking care intracranial pressure monitoring, etc. of a burn patient.” Electrical burns on the skin do not necessarily 8. “My patient had a high-voltage burn that had give a clear picture as to how much tissue entry at his head and exit from the right arm. was actually damaged by thermal and He had some minor facial burns and an arm electrical energy. Isotonic IV fluids sufficient fracture. We admitted him to the floor, but he to maintain urine output at 1.0 to 1.5 cc/kg/ boarded in the ED for a while. I’m glad he did, hr must be given to these patients. Continue because he became progressively more dys- fluid resuscitation until you reach that urine pneic and needed emergent intubation. He had output and urine myoglobin has cleared. a lot of edema; I barely got the tube passed.” Fluid requirements may be much higher than Remember that the extent of burn seen on the specified by the Parkland formula. CK levels skin in high-voltage burns may not give an and myoglobinuria should be monitored. accurate picture of underlying burn injury. You cannot use traditional burn metrics of soot in the mouth or nares, facial hair singeing, or burns to

November 2018 • www.ebmedicine.net 13 Copyright © 2018 EB Medicine. All rights reserved. Time- and Cost-Effective Strategies 9. Biegelmeier P. New knowledge on the impedance of the human body. In: Bridges J, Ford G, Sherman I, et al, eds. Electrical Shock Safety Criteria: Proceedings of the First Interna- • Cardiac monitoring in patients with no arrhyth- tional Symposium on Electrical Shock Safety Criteria. New York, mia, syncope, or ECG changes is unnecessary. NY: Pergamon Press/Elsevier; 1985:115-132. (Conference • Do not delay transfer to a burn center; once you proceedings) have determined that transfer is necessary and 10. Fish R. Electric shock, part I: physics and pathophysiology. J Emerg Med. 1993;11(3):309-312. (Review article) the patient is stabilized, further diagnostic test- 11 Fish R. Electric shock, part II: nature and mechanisms of ing may delay definitive care. injury. J Emerg Med. 1993;11(4):457-462. (Review article) • Many low-voltage exposures may be safely 12. 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Inner ear damage cardiac effects relative to non fatal injuries and post-mortem following electric current and lightning injury: a literature findings in fatal cases.Int J Cardiol. 2006;111(1):6-11. (Analy- review. Eur Arch Otorhinolaryngol. 2014;271(5):855-861. sis of case series; 32 patients) (Meta-analysis; 35 articles) 30. Bailey B, Gaudreault P, Thivierge RL. Cardiac monitoring 48. Canady JW, Thompson SA, Bardach J. Oral commissure of high-risk patients after an electrical injury: a prospective burns in children. Plast Reconstr Surg. 1996;97(4):738-744. multicentre study. Emerg Med J. 2007;24(5):348-352. (Retro- (Descriptive study; 24 patients) spective study; 134 patients) 49. Thomas SS. Electrical burns of the mouth: still searching 31.* Hansen SM, Riahi S, Hjortshøj S, et al. Mortality and risk for an answer. Burns. 1996;22(2):137-140. (Review and case of cardiac complications among immediate survivors of report; 5 patients) accidental electric shock: a Danish nationwide cohort study. 50. Morrison M, Woollard M. Outcome of asymptomatic electric BMJ Open. 2017;7(8):e015967. (Retrospective study; 11,462 shock victims requesting an emergency ambulance. Prehosp patients) Emerg Care. 2004;8(4):400-404. (Retrospective study; 52 32.* Searle J, Slagman A, Maass W, et al. Cardiac monitoring in patients) patients with electrical injuries. An analysis of 268 patients at 51. Murphy P, Colwell C, Pineda G, et al. A shocking call. Pre- the Charité Hospital. Dtsch Arztebl Int. 2013;110(50):847-853. hospital assessment and management of electrical injuries (Retrospective study; 268 patients) and lightning strikes. EMS Mag. 2010;39(2):46-50. (Clinical 33. Celebi A, Gulel O, Cicekcioglu H, et al. Myocardial infarc- review) tion after an electric shock: a rare complication. Cardiol J. 52. Callaway CW, Soar J, Aibiki M, et al. Part 4: Advanced life 2009;16(4):362-364. (Case report; 1 patient) support: 2015 international consensus on cardiopulmonary 34. Oliva PB, Breckinridge JC. Acute myocardial infarction with resuscitation and emergency cardiovascular care science normal and near normal coronary arteries. Documentation with treatment recommendations. Circulation. 2015;132(16 with coronary arteriography within 12 1/2 hours of the on- Suppl 1):S84-S145. (Expert consensus) set of symptoms in two cases (three episodes). Am J Cardiol. 53. Motawea M, Al-Kenany AS, Hosny M, et al. Survival with- 1977;40(6):1000-1007. (Case series; 2 patients) out sequelae after prolonged cardiopulmonary resuscitation 35. Hunt JL, McManus WF, Haney WP, et al. Vascular lesions in after electric shock. Am J Emerg Med. 2016;34(3):e671-e672. acute electric injuries. J Trauma. 1974;14(6):461-473. (Quasi- (Case report; 1 patient) experimental study; 11 patients) 54. Marcus MA, Thijs N, Meulemans AI. A prolonged but suc- 36. Pannucci CJ, Osborne NH, Jaber RM, et al. Early fasciotomy cessful resuscitation of a patient struck by lightning. Eur J in electrically injured patients as a marker for injury severity Emerg Med. 1994;1(4):199-202. (Case report; 1 patient) and deep venous thrombosis risk: an analysis of the National 55. Hsueh YY, Chen CL, Pan SC. Analysis of factors influencing Burn Repository. J Burn Care Res. 2010;31(6):882-887. (Retro- limb amputation in high-voltage electrically injured patients. spective study; 1469 patients) Burns. 2011;37(4):673-677. (Retrospective study; 82 patients) 37. Wahl WL, Brandt MM, Ahrns KS, et al. Venous thrombosis 56. Kim SH, Cho GY, Kim MK, et al. Alterations in left ventricu- incidence in burn patients: preliminary results of a prospec- lar function assessed by two-dimensional speckle tracking tive study. J Burn Care Rehabil. 2002;23(2):97-102. (Prospective echocardiography and the clinical utility of cardiac troponin study; 30 patients) I in survivors of high-voltage electrical injury. Crit Care Med. 38. Wibbenmeyer LA, Hoballah JJ, Amelon MJ, et al. The preva- 2009;37(4):1282-1287. (Prospective study; 20 patients) lence of venous thromboembolism of the lower extremity 57. Ketenci IE, Duymus TM, Ulusoy A, et al. Bilateral posterior among thermally injured patients determined by duplex shoulder dislocation after electrical shock: a case report. Ann sonography. J Trauma. 2003;55(6):1162-1167. (Prospective Med Surg (Lond). 2015;4(4):417-421. (Case report; 1 patient) study; 148 patients) 58. Costa Santos D, Barros F, Frazao M, et al. Pre-burn centre 39. Singerman J, Gomez M, Fish JS. Long-term sequelae of low- management of the airway in patients with face burns. Ann voltage electrical injury. J Burn Care Res. 2008;29(5):773-777. Burns Fire Disasters. 2015;28(4):259-263. (Retrospective study; (Retrospective study; 38 patients) 136 patients) 40.* Bailey B, Gaudreault P, Thivierge RL. Neurologic and 59. Esnault P, Prunet B, Cotte J, et al. Tracheal intubation diffi- neuropsychological symptoms during the first year after an culties in the setting of face and neck burns: myth or reality? electric shock: results of a prospective multicenter study. Am Am J Emerg Med. 2014;32(10):1174-1178. (Prospective study; J Emerg Med. 2008;26(4):413-418. (Prospective cohort study; 134 patients) 86 patients) 60.* Avni T, Levcovich A, Ad-El DD, et al. Prophylactic antibiot- 41. Tondel M, Blomqvist A, Jakobsson K, et al. [Immediate and ics for burns patients: systematic review and meta-analysis. delayed outcomes after electrical injury. A guide for clini- BMJ. 2010;340:c241. (Meta-analysis; 17 trials) cians]. Lakartidningen. 2016 Dec 1;113. (Descriptive study 61. Barajas-Nava LA, Lopez-Alcalde J, Roqué i Figuls M, et al. and review of Swedish national data; 300 patients) Antibiotic prophylaxis for preventing burn wound infection. 42. Varghese G, Mani MM, Redford JB. Spinal cord injuries Cochrane Database Syst Rev. 2013(6):CD008738. (Cochrane following electrical accidents. Paraplegia. 1986;24(3):159-166. review; 36 randomized controlled trials, 2117 participants) (Retrospective; 116 patients) 62. Coban YK. Infection control in severely burned patients. 43. Arevalo JM, Lorente JA, Balseiro-Gomez J. Spinal cord World J Crit Care Med. 2012;1(4):94-101. (Review article) injury after electrical trauma treated in a burn unit. Burns. 63. Pannucci CJ, Diaz JA, Wahl WL. Temporal changes in DVT 1999;25(5):449-452. (Case report; 1 patient) risk after electrical injury. J Burn Care Res. 2011;32(3):442-446. 44. Platen S, Backhaus R, Kirzinger L, et al. P29. Trans- (Retrospective study; 77 patients) versal spinal cord lesion after electrical injury. Clin 64. Gifford GH Jr, Marty AT, MacCollum DW. The manage- Neurophysiol.126(8):e111. (Case report; 1 patient) ment of electrical mouth burns in children. Pediatrics. 45. Marques EG, Junior GA, Neto BF, et al. Visceral injury in 1971;47(1):113-119. (Historical expert consensus article)

November 2018 • www.ebmedicine.net 15 Copyright © 2018 EB Medicine. All rights reserved. 65. Jaffe R, Fejgin M. Accidental electric shock in preg- 2007;28(1):134-141. (Practice guidelines) nancy: a prospective cohort study. Am J Obstet Gynecol. 88. Tagami T, Matsui H, Fushimi K, et al. Prophylactic an- 1997;177(4):983-984. (Prospective study; 32 patients) tibiotics may improve outcome in patients with severe 66. Awwad J, Hannoun A, Fares F, et al. Accidental electric burns requiring mechanical ventilation: Propensity score shock during pregnancy: reflection on a case.AJP Rep. analysis of a Japanese nationwide database. Clin Infect Dis. 2013;3(2):103-104. (Case report; 1 patient) 2016;62(1):60-66. (Retrospective study; 2893 patients) 67. Goldman RD, Einarson A, Koren G. Electric shock during pregnancy. Can Fam Physician. 2003;49:297-298. (Review) 68. Haileyesus T, Annest JL, Mercy JA. Non-fatal conductive en- CME Questions ergy device-related injuries treated in US emergency depart- ments, 2005-2008. Inj Prev. 2011;17(2):127-130. (Retrospective study; 75,000 patients per year) Take This Test Online! 69. Le Blanc-Louvry I, Gricourt C, Touré E, et al. A brain pen- etration after Taser injury: controversies regarding Taser gun Current subscribers receive CME credit absolutely safety. Forensic Sci Int. 2012;221(1-3):e7-e11. (Case report; 1 free by completing the following test. Each issue patient) includes 4 AMA PRA Category 1 CreditsTM, 4 ACEP 70. Zipes DP. Sudden cardiac arrest and death following ap- Category I credits, 4 AAFP Prescribed credits, or plication of shocks from a TASER electronic control device. Take This Test Online! Circulation. 2012;125(20):2417-2422. (Case report; 1 patient) 4 AOA Category 2-A or 2-B credits. Online testing 71.* Zipes DP. TASER electronic control devices can cause cardiac is available for current and archived issues. To arrest in humans. Circulation. 2014;129(1):101-111. (Case receive your free CME credits for this issue, scan reports; 8 patients) the QR code below with your smartphone or visit 72. Kunz SN. Biases in TASER research. Am Heart J. 2012;163(3):e7-e8. (Review) www.ebmedicine.net/E1118. 73. Kroll MW, Lakkireddy DR, Stone JR, et al. TASER electronic control devices and cardiac arrests: coincidental or causal? Circulation. 2014;129(1):93-100. (Response article) 74. White MD, Ready JT, Kane RJ, et al. Examining cognitive functioning following TASER exposure: a randomized controlled trial. Appl Cog Psych. 2015;29(4):600-607. (Random- ized controlled trial; 142 patients) 75. Coad F, Maw G. TASERed during training: an unusual scapular fracture. Emerg Med Australas. 2014;26(2):206-207. (Case report; 1 patient) 1. Injuries from high-voltage electrical shock can 76. Cherington M. Lightning injuries. Ann Emerg Med. 25(4):516- 519. (Practice guidelines) affect any organ system. Regarding high-volt- 77. Pfortmueller CA, Yikun Y, Haberkern M, et al. Injuries, se- age injuries, which of the following is TRUE? quelae, and treatment of lightning-induced injuries: 10 years a. These injuries are less likely than low- of experience at a Swiss trauma center. Emerg Med Internat. voltage injuries to cause rhabdomyolysis. 2012;2012:167698. (Retrospective study; 9 patients) b. The extent of skin burns is likely to reflect 78. Gluncic I, Roje Z, Gluncic V, et al. Ear injuries caused by lightning: report of 18 cases. J Laryngol Otol. 2001;115(1):4-8. underlying deep tissue burns. (Case series; 18 patients) c. Electrical energy will preferentially take the 79. McIntyre WF, Simpson CS, Redfearn DP, et al. The lightning path of least resistance but may overcome heart: a case report and brief review of the cardiovascular skin resistance in high-voltage exposure. complications of lightning injury. Indian Pacing Electrophysiol d. Fluid resuscitation should proceed J. 2010;10(9):429-434. (Case report; 1 patient) 80. Aslan S, Yilmaz S, Karcioglu O. Lightning: an unusual cause according to the Parkland formula based of cerebellar infarction. Emerg Med J. 2004;21(6):750-751. on the percentage of total body surface area (Case report; 1 patient) that is burned. 81. Emet M, Caner I, Cakir M, et al. Lightning injury may cause abrupt cerebral salt wasting syndrome. Am J Emerg Med. 2. Which of the following tissues offers the most 2010;28(5):e641-e643. (Case report; 1 patient) 82. Rahmani SH, Faridaalaee G, Jahangard S. Acute transient resistance to electricity? hemiparesis induced by lightning strike. Am J Emerg Med. a. Nerve 2015;33(7):984.e1-3. (Case report; 1 patient) b. Muscle 83. Ward NJ, Little JH, Higgins GL 3rd. Man with confusion and c. Vascular resolved paralysis. Lightning strike injury. Ann Emerg Med. d. Bone 2012;59(4):335-340. (Case report; 1 patient) 84. Emet M, Aslan S, Cakir Z, et al. Subcortical parenchymal and right lentiform nucleus haemorrhages in a lightning victim. Hong Kong J Emerg Med. 2009;16(3):172-175. (Case report; 1 patient) 85. ten Duis HJ, Klasen HJ, Reenalda PE. Keraunoparalysis, a ‘specific’ lightning injury. Burns Incl Therm Inj. 1985;12(1):54- 57. (Case report; 1 patient) 86. Whitcomb D, Martinez JA, Daberkow D. Lightning injuries. South Med J. 2002;95(11):1331-1334. (Case report and review) 87. American Burn Association, American College of Surgeons. Guidelines for the operation of burn centers. J Burn Care Res.

Copyright © 2018 EB Medicine. All rights reserved. 16 Reprints: www.ebmedicine.net/empissues 3. A 20-year-old man who experienced a low- 6. A 36-year-old man presents to the ED with voltage electrical exposure through his hands a complaint of electrical shock while chang- is ready for discharge from the ED. He is ing an outlet. He states that his screwdriver concerned about possible delayed complica- touched across the contacts, causing a bright tions from his injury. Which of the following flash and a loud noise. He has no apparent concerns could be a delayed complication of a burns or trauma, no syncope, and a normal low-voltage injury? ECG. What is the appropriate management for a. Cardiac rhythm changes, palpitations, and this patient? chest pain a. Admit for further cardiac monitoring. b. Mood swings and depression b. Discharge home with outpatient follow-up, c. Vision loss from cataracts including precautions for the development d. Fractures missed on the initial examination of paresthesia, pain where he was shocked, muscle spasm, or chest pain. 4. A 2-year-old child presents to your ED after c. Order CBC, CMP, creatine kinase, urinalysis, chewing on an electrical cord. A small burn is aggressive fluid resuscitation, and burn unit seen at the corner of the mouth. The child has admission. no active bleeding and no evidence of airway d. Order x-rays of the hand holding the involvement. What is the appropriate next step screwdriver, and discharge if they are in treatment of this patient? normal. a. Early intubation and admission or transfer to pediatric intensive care is the standard of 7. A 32-weeks’ pregnant patient presents to the care. ED after accidentally grasping a clothes dryer b. Administer early IV antibiotics, as the cord (240 V) that had exposed wiring. She primary risk is secondary infection. felt an electric shock, but has no worrisome c. Obtain ENT consultation and give parental findings of burns, vascular or compartment instruction for delayed bleeding. syndrome, and has a normal ECG. She is con- d. Apply oral splinting and order ENT follow- cerned about her fetus. Based on your knowl- up. edge of electrical injuries in pregnancy, your next step in the care of this patient and her 5. A 27-year-old electrical lineman presented to fetus is: your small community ED after a high-voltage a. Discharge home with instructions to follow line injury. He had a loss of consciousness and up with her obstetrician. fell from height out of his bucket truck. He has b. Listen for fetal heart tones; if they are burns to his left arm, chest wall, and both feet, normal, the patient can be discharged for and is found to have a pneumothorax, multiple follow-up with her obstetrician. rib fractures, and a grade II splenic lacera- c. Admit for maternal cardiac monitoring. tion. After initial evaluation and stabilization, d. Monitor both the patient and fetus. including intubation and chest tube insertion, you determined that he requires a higher level 8. The police arrive with a 24-year-old man who of care and will require transfer. Regarding was subdued using an electrical control device his immediate care, which of the following is (Taser). He is very anxious, complaining of TRUE? chest pain, and has mydriatic pupils bilaterally. a. His burn care takes precedence over the Vital signs are: heart rate, 132 beats/min; blood trauma care, and he should be transferred to pressure, 154/90, mm Hg; temperature, 37.4°C;

the burn center. respiration, 26 breaths/min; PaO2, 99% on room b. His trauma care takes precedence over the air. His ECG shows only sinus tachycardia. burn care, and he should be transferred to Proper treatment and disposition include: the trauma center. a. He can be discharged into police custody. c. IV fluids should be given according to the b. He should receive a chest x-ray to go along Parkland formula for burn resuscitation. with the ECG; if it is negative, he can be d. From an electrical standpoint, he should not discharged. require further cardiac monitoring. c. He should be evaluated for causes of his chest pain and treated for sympathomimetic toxicity. d. He needs a workup for the possibility of burns to deep muscle compartments.

November 2018 • www.ebmedicine.net 17 Copyright © 2018 EB Medicine. All rights reserved. 9. EMS brings in 3 young adults from a local 10. You are evaluating a patient who has been outdoor concert. It is storming outside, and struck by lightning. He complains of tinnitus apparently the 3 patients were separated from that progresses quickly to deafness. Regarding the crowd, underneath a tree. One is in cardiac hearing loss after a lightning strike, which of arrest, one is dazed and has a fine branching the following is TRUE? rash on the upper extremities, and one is un- a. Hearing loss is permanent after these conscious but breathing. Regarding the initial injuries because the auditory nerves are care of these patients, which of the following is permanently damaged. TRUE? b. The tympanic membrane can be ruptured by a. Care should be prioritized to the patient the force of the lightning strike. who is unconscious but breathing. c. Inner ear structures are not at risk of b. The red markings are indicative of deep damage from lightning injuries. cutaneous injury. d. Hearing loss is always immediate. c. There is a low likelihood of significant trauma in these patients. d. CPR and ACLS are much more likely to be successful in this cardiac arrest patient than in the general population.

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Calculated Decisions – Clinical Decision Tools to Help in Clinical Care

CalculatedPOWERED BY NEW: Calculated Decisions—this must-read online supplement, published in collaboration with MDCalc, Decisions Clinical Decision Support for Emergency Medicine Practice Subscribers Emergency Department Assessment gives you how-to-use guidance and reviews of medical calculators. These formulas, algorithms, rules, and of Chest Pain Score (EDACS) Introduction: The EDACS identifies patients with chest pain who 17+ are at low risk for a major adverse cardiac event. Click the thumbnail above to access the calculator.

Points & Pearls • The EDACS accelerated diagnostic protocol Why to Use scores will help you make informed decisions when caring for your patients. (EDACS-ADP) study included any symptoms Patients requiring serial blood testing (serial lasting longer than 5 minutes that the attending troponin markers, typically at 0 and 6 hours, to Calculators physician thought were worth working up for rule out myocardial infarction) and further risk possible acute coronary syndromes (ACS). This stratification require an extended ED evaluation is a broader definition than other studies, such or hospital admission, leading to crowding, bed as the Vancouver Chest Pain Score, which only included chest pain patients. allocation problems, and exposure of patients • Like other chest pain evaluation studies, the pri- to side effects of increased testing. The study mary outcome for the EDACS-ADP study was a authors were able to find a group of low-risk major adverse cardiac event (MACE), as defined patients (~45%) who could be safely discharged by any of the following: from the ED after 2 biomarkers just 2 hours Calculated - ST-elevation or non-ST-elevation myocardial apart, along with ECG, history, and physical infarction examination. - Requiring an emergency revascularization procedure When to Use - Death from cardiovascular causes Use in patients with chest pain or other anginal - Ventricular arrhythmia Decisions - Cardiac arrest symptoms requiring evaluation for possible - Cardiogenic shock ACS, who may potentially be at low risk and ap- Get it now—absolutely free—at www.ebmedicine.net/topics by clicking next to - High atrioventricular block propriate for early discharge from the ED. • The goal of these rules is to identify a low-risk population of patients who need less testing Next Steps than other, higher-risk patients. As a rule-out • For low-risk patients, consider other causes calculator, the EDACS is good at identifying of chest pain due to aortic, esophageal, who is relatively safe to go home (highly sensi- pulmonary, cardiac, abdominal, or musculo-

CALCULATOR REVIEW AUTHORS skeletal sources prior to discharge. • For non–low-risk patients, physicians should Graham Walker, MD use best judgment to work up and treat as the title of the issue. Department of Emergency Medicine per usual chest pain protocols, including but Kaiser Permanente San Francisco, San Francisco, CA not limited to consideration of aspirin, nitro- glycerin, and serial ECGs and biomarkers. Joseph Habboushe, MD, MBA Department of Emergency Medicine Abbreviations: ED, emergency department; ECG, NYU Langone / Bellevue Medical Center, New York, NY electrocardiogram.

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Points & Pearls – A Digest That Reinforces What You Learn

POINTS & PEARLS Points & Pearls—a two-page online digest of each monthly journal article. Points & Pearls features: A Quick-Read Review Of Key Points & Clinical Pearls, April 2017 Maxillofacial Trauma: Managing Potentially • Key points and clinical pearls from the full-length issue Dangerous And Disfiguring Complex Injuries

Points Pearls • The main cause of death in severe facial injury is airway obstruction. As with any trauma, perform Severe maxillofacial trauma should prompt ABCDE’s first. brain and cervical spine imaging. • Signs of cerebrospinal fluid (CSF) leak include clear 230+ rhinorrhea, subcutaneous emphysema, mental status Always perform a full neurological examination to assess for nerve and muscle entrapment • A key figure or table and relevant links changes, new malocclusion, or limited extraocular movements. Studies have shown that a persistent in the head and neck. CSF leak increase the risk for future meningitis. Reassess hematomas and soft-tissue edema af- • Midface bleeding can be difficult to control. Even ter initial stabilization; better to detect impend- relatively minor facial injuries (such as nasal ing airway compromise early. fractures and displaced mandibular fractures) may cause continued slow bleeding that may lead to Ultrasound for ocular injuries and fractures is Points & eventual need for aggressive resuscitation. fast, effective, cheap, and safe. • Frontal sinus fractures occur only with high-impact trauma. A retrospective review showed that frontal • A quick summary of the must-know recommendations from the full issue sinus fractures rarely occurred in isolation and were infection rates in mandibular, zygomatic, and Le often associated with intracranial injuries. Long-term Fort fractures when patients were given antibiot- sequelae of these fractures include chronic sinusitis, ics perioperatively. Current evidence has shown mucocele, mucopyocele, meningitis, brain abscess, that giving antibiotic prophylaxis beyond 24 frontal osteomyelitis, and CSF leak. hours perioperatively or postoperatively had no • Even soft-tissue injuries to the maxillofacial region significant additional benefit to the patient. may have associated injuries to the cervical spine. • Prior studies have shown that septal abscesses Pearls Injuries to the midface are most likely associated (potential sequelae from septal hematomas, if left with C5-C7 disruption; injuries to the lower face are untreated) may lead to perforation or permanent likely associated with C1-C4 disruption. saddle-nose deformity. A septal hematoma should • Displaced zygoma fractures require treatment within be incised, aspirated, and packed immediately. 10 days. Untreated fractures may cause cosmetic Packing should be removed within 3 to 4 days. deformity or limited mandibular movement. Patients should be instructed to apply pressure to the affected side and to avoid nose-blowing. DIGEST • Initial management of orbital trauma includes ice Issue Authors for 48 hours, elevation of the head of the bed, nasal Devjani Das, MD, RDMS, FACEP decongestants, a broad-spectrum antibiotic, nonste- Assistant Professor, Associate Director and Co-Fellowship Director, Division roidal anti-inflammatory drugs, and avoidance of of Emergency Ultrasound, Department of Emergency Medicine, Hofstra Northwell School of Medicine, Northwell Health-Staten Island University Get it now—absolutely free—at www.ebmedicine.net/topics by clicking next to nose-blowing and Valsalva maneuvers. Hospital, Staten Island, NY • Orbital compartment syndrome from ocular hema- Lea Salazar, MD tomas may result in irreversible blindness. Orbital Clinical Assistant Professor, Department of Emergency Medicine, Division compartment syndrome is a clinical diagnosis, and of Emergency Ultrasound, Hofstra Northwell School of Medicine, Northwell Health-Staten Island University Hospital, Staten Island, NY early recognition is necessary to allow for emergent orbital decompression via lateral canthotomy. Points & Pearls Contributor • Prophylactic antibiotics for facial trauma is contro- Milana Zaurova, MD Department of Emergency Medicine, Icahn School of Medicine at Mount versial. Several studies have reported a decrease in Sinai, New York, NY

Points & Pearls contributors: Nachi Gupta, MD, PhD and Jeff Nusbaum, MD

The CME You Need – At No Extra Charge FREE CME: Each issue of Emergency Medicine Practice includes 4 CME credits at no extra charge. And did you know you can also receive 4 CME credits from any Emergency Medicine Practice issue published within the last three years, all archived on our website for easy access to the journal content and CME tests? That’s up to 144 additional CME credits—absolutely free! Each issue is approved for: • AMA PRA Category 1 CreditsTM • ACEP Category I Credits • AAFP Prescribed Credits 84,000+ • AOA Category 2-A or 2-B credits credits earned each year Visit www.ebmedicine.net/CME to start earning credits today!

Maxillofacial Trauma: Managing March 2017 BIG DISCOUNTS: Did you know you can get a $75 coupon just for referring your colleagues to us? Potentially Dangerous And Volume 19, Number 3 April 2017 Authors Disfiguring Complex Injuries Authors Volume 19, Number 4 Cynthia Santos, MD Devjani Das, MD, RDMS, FACEP Sedative-Hypnotic Drug Department of Emergency Medicine, Emory University Hospital, Atlanta, Abstract Assistant Professor, Associate Director and Co-Fellowship Director, GA Division of Emergency Ultrasound, Department of Emergency Medicine, Ruben E. Olmedo, MD Hofstra Northwell School of Medicine, Northwell Health-Staten Island Withdrawal Syndrome: Director, Division of Toxicology, Department of Emergency Medicine, Icahn Patients with maxillofacial trauma require a careful evaluation University Hospital, Staten Island, NY School of Medicine at Mount Sinai, New York, NY due to the anatomical proximity of the maxillofacial region to Lea Salazar, MD Clinical Assistant Professor, Department of Emergency Medicine, Division Peer Reviewers the head and neck. Facial injuries can range from soft-tissue Recognition And Treatment of Emergency Ultrasound, Hofstra Northwell School of Medicine, Northwell Catherine A. Gogela Carlson, MD lacerations and nondisplaced nasal fractures to severe, complex Health-Staten Island University Hospital, Staten Island, NY Department of Critical Care Medicine and Emergency Medicine, Carolinas fractures, eye injuries, and possible brain injury. Though the Ad May 2017 Peer Reviewers Simply visit www.ebmedicine.net/refer to take advantage of this offer. Abstract Medical Center, Charlotte, NC Acute Decompensated Volumevanced 19, Number Trauma 5 Life Support (ATLS) guidelines provide a frame Victor Tuckler, MD Syed Sameer Ali, MD, MS, FACEP Authors work for the management of trauma patients, they do not provide Assistant Professor, Department of Emergency Medicine, Baylor College Sedative-hypnotic drugs include gamma-Aminobutyric acid Clinical Instructor of Emergency Medicine, Louisiana State University - Health Sciences Center, New Orleans, LA Heart Failure: a detailed reference for many subtle or complex facial injuries. of Medicine; Attending Physician, Department of Emergency Medicine, (GABA)ergic agents such as benzodiazepines, barbiturates, Emily Singer Fisher, MDThis issue adds a more comprehensive and systematic approach- Ben Taub General Hospital; Trauma Medical Director, Clinical Attending gamma-Hydroxybutyric acid [GHB], gamma-Butyrolactone CME Objectives Assistant Professor, Department of Emergency Medicine, University of Physician, Memorial Hermann Memorial City Medical Center, Houston, TX Oklahoma School of Communityto the Medicine, secondary Tulsa, OK survey of the maxillofacial area and emergency [GBL], baclofen, and ethanol. Chronic use of these substances Upon completion of this article, you should be able to: New Strategies for Tiffany Murano, MD, FACEP 1. Describe the etiology and physiological basis of commonly Boyd Burns, DO, FACEP,department FAAEM management of injuries to the face. In addition to an Clinical Associate Professor, Department of Emergency Medicine, Program can cause tolerance, and abrupt cessation or a reduction in the encountered sedative-hypnotic withdrawal syndromes. George Kaiser Foundationoverall Chair in Emergency review Medicine,of maxillofacial Associate trauma pathophysiology, associ Director, Emergency Medicine Residency, St. John’s Riverside Hospital, Professor & Program Director, Department of Emergency Medicine, Yonkers, NY quantity of the drug can precipitate a life-threatening with- 2. Recognize how different withdrawal syndromes may present. Improving Outcomes University of Oklahoma Schoolated of injuries, Community and Medicine, physical Tulsa, OK examination, this review will also drawal syndrome. Benzodiazepines, phenobarbital, propofol, 3. Identify and manage high-risk and critically ill patients presenting with sedative-hypnotic withdrawal. discuss relevant imaging, treatment, and disposition plans. Prior to beginning this activity, see “Physician CME Information” and other GABA agonists or analogues can effectively control Peer Reviewers - 4. Discuss the various pharmacological options for treatment of Abstract symptoms of withdrawal from GABAergic agents. Managing sedative-hypnotic withdrawal syndromes. Sinem Sherifali, MD on the back page. withdrawal symptoms requires a patient-specific approach that Assistant Professor ofEditor-In-Chief Emergency Medicine, University of Florida This issue is eligible for 4 Trauma CME credits Prior to beginning this activity,on the back see “Physicianpage. CME Information”Acute decompensated heart failure is a common emergency Jacksonville, Jacksonville,Andy Jagoda, FL MD, FACEP Daniel J. Egan, MD takes into account the physiological pathways of the particu- Professor and Chair, Department of International Editors department presentation with significant associated morbidity Scott M. Silvers, MD Associate Professor, Department lar drugs used, as well as the patient's age and comorbidities. Associate Professor andEmergency Chair, Medicine,Department Icahn of School Emergency Medicine, Mayo Eric Legome, MD Peter Cameron, MD and mortality. Heart failure accounts for more than 1 million of Medicine at Mount Sinai, Medical of Emergency Medicine, Program Robert Schiller, MD Academic Director, The Alfred Clinic, Jacksonville, FL Director, Emergency Medicine Chair, Emergency Medicine, Mount Adjunctive therapies include alpha-2 agonists, beta blockers, Director, Mount Sinai Hospital, New Robert Schiller, MD Chair, Department of Family Medicine, Emergency and Trauma Centre,hospitalizations annually, with a steadily increasing incidence Residency, Mount Sinai St. Luke's Sinai West & Mount Sinai St. Luke's; York, NY Chair, Department of Family Medicine, anticonvulsants, and antipsychotics. Newer pharmacologicalEric Legome, MD Beth Israel Medical Center; Senior Monash University, Melbourne, CME Objectives Roosevelt, New York, NY Vice Chair, Academic Affairs for Chair, Emergency Medicine, Mount Faculty, Family Medicine and as our population ages. This issue reviews recent literature Emergency Medicine, Mount Sinai Beth Israel Medical Center; Senior International Editors Australia Associate Editor-In-Chief Nicholas Genes, MD, PhD therapies offer promise in managing withdrawal Sinaisymptoms. West & Mount Sinai St. Luke's; Community Health, Icahn School of Health System, Icahn School of Faculty, Family Medicine and Peter Cameron, MD Daniel J. Egan, MD regarding appropriate management of emergency department Upon completion ofKaushal this article, Shah, youMD, shouldFACEP be able to: Vice Chair, Academic Affairs for Medicine at Mount Sinai, New York, NY Giorgio Carbone, MD Associate Professor, Department of Medicine at Mount Sinai, New York, NY Community Health, Icahn School of Associate Professor, Department Associate Professor, Department of Academic Director, The Alfred Emergency Medicine, Mount Sinai Chief, Department of Emergency 1. Diagnose acute exacerbations of heart failure usingEmergency a focused Medicine, Icahn School Medicine at Mount Sinai, New York, NY of Emergency Medicine, Program Scott Silvers, MD, FACEP presentations of acute decompensated heart failure, with special Emergency Medicine, Icahn School Keith A. Marill, MD Emergency and Trauma Centre, Editor-In-Chief Health System, Icahn School of Medicine Ospedale Gradenigo, physical examination and appropriate adjunct testing.of Medicine at Mount Sinai, New Director, Emergency Medicine Chair, Department of Emergency of Medicine at Mount Sinai, New Research Faculty, Department of Scott Silvers, MD, FACEP Monash University, Melbourne, Andy Jagoda, MD, FACEP Medicine at Mount Sinai, New York, NY Torino, Italy attention to newer medication options. Emergency department York, NY Residency, Mount Sinai St. Luke's Medicine, Mayo Clinic, Jacksonville, FL 2. Identify alternativeYork, NY causes of dyspnea and discuss how to distinguish Emergency Medicine, University Chair, Department of Emergency Australia Professor and Chair, Department of Michael A. Gibbs, MD, FACEP Roosevelt, New York, NY Keith A. Marill, MD Suzanne Y.G. Peeters, MD of Pittsburgh Medical Center, Medicine, Mayo Clinic, Jacksonville, FL Emergency Medicine, Icahn School Corey M. Slovis, MD, FACP, FACEP management and appropriate interventions are discussed, along them from heart failure. Giorgio Carbone, MD Research Faculty, Department of Attending Emergency Physician, Editorial Board Professor and Chair, Department Pittsburgh, PA of Medicine at Mount Sinai, Medical Nicholas Genes, MD, PhD Professor and Chair, Department Corey M. Slovis, MD, FACP, FACEP Chief, Department of Emergency Emergency Medicine, University Flevo Teaching Hospital, withAlmere, critical decision-making points in resuscitation for both 3. DetermineSaadia the appropriate Akhtar, MD ED management of acuteof Emergency decompensated Medicine, Carolinas Director, Mount Sinai Hospital, New Associate Professor, Department of of Emergency Medicine, Vanderbilt Charles V. Pollack Jr., MA, MD, Professor and Chair, Department Medicine Ospedale Gradenigo, of Pittsburgh Medical Center, The Netherlands heart failure and manage those at risk for rapid Medicaldeterioration. Center, University of North York, NY Emergency Medicine, Icahn School University Medical Center, Nashville, TN Associate Professor, Department of FACEP of Emergency Medicine, Vanderbilt Torino, Italy Pittsburgh, PA hypertensive and hypotensive patients. Carolina School of Medicine, Chapel of Medicine at Mount Sinai, New Hugo Peralta, MD Emergency Medicine, Associate Dean Professor and Senior Advisor for University Medical Center, Nashville, TN If there are 5 or more clinicians at your hospital or group who are interested in subscribing, you can get Hill, NC Suzanne Y.G. Peeters, MD Ron M. Walls, MD Chair of Emergency Services, for Graduate Medical Education, Interdisciplinary Research and Associate Editor-In-Chief York, NY Charles V. Pollack Jr., MA, MD, Prior to beginning this activity, see “Physician CME Information” Ron M. Walls, MD Attending Emergency Physician, Professor and Chair, Department of Hospital Italiano, Buenos Aires, Program Director, Emergency Steven A. Godwin, MD, FACEP Clinical Trials, Department of Kaushal Shah, MD, FACEP FACEP Emergency Medicine, Brigham and on the back page. Professor and Chair, Department of Flevo Teaching Hospital, Almere, Associate Professor, Department of Michael A. Gibbs, MD, FACEP Professor and Senior Advisor for Argentina Medicine Residency, Mount Sinai Professor and Chair, Department Emergency Medicine, Sidney Kimmel Women's Hospital, Harvard Medical Emergency Medicine, Brigham and The Netherlands Emergency Medicine, Icahn School Professor and Chair, Department Beth Israel, New York, NY of Emergency Medicine, Assistant Medical College of Thomas Jefferson Interdisciplinary Research and Dhanadol Rojanasarntikul, MD Women's Hospital, Harvard Medical of Emergency Medicine, Carolinas School, Boston, MA Daniel J. Egan, MD Eric Legome, MD Robert Schiller, MD Dean, Simulation Education, University, Philadelphia, PA Hugo Peralta, MD of Medicine at Mount Sinai, New Clinical Trials, Department of Attending Physician,Editor-In-Chief Emergency International Editors Medical Center, University of North Associate Professor, Department Chair, Emergency Medicine, Mount Chair, DepartmentWilliam J.of Brady,Family Medicine,MD University of Florida COM- School, Boston, MA York, NY Emergency Medicine, Sidney Kimmel Medicine, King ChulalongkornAndy Jagoda, MD, FACEP Peter Cameron, MD Michael S. Radeos, MD, MPH Chair of Emergency Services, Carolina School of Medicine, Chapel Critical Care Editors of Emergency Medicine, Program Sinai West & Mount Sinai St. Luke's; Beth Israel ProfessorMedical Center; of Emergency Senior Medicine Jacksonville, Jacksonville, FL Hospital Italiano, Buenos Aires, Medical College of Thomas Jefferson Memorial Hospital, ProfessorThai Red Cross,and Chair, Department of Academic Director, The Alfred Associate Professor of Emergency Critical Care Editors Hill, NC Director, Emergency Medicine Vice Chair, Academic Affairs for Faculty, Familyand Medicine;Medicine and Chair, Medical Argentina Editorial Board University, Philadelphia, PA William A. Knight IV, MD, FACEP Thailand; Faculty ofEmergency Medicine, Medicine, Icahn School Emergency Response Committee;Emergency Gregory and Trauma L. Henry, Centre, MD, FACEP Medicine, Weill Medical College Steven A. Godwin, MD, FACEP Associate Professor of Emergency of Medicine at Mount Sinai, Medical Residency, Mount Sinai St. Luke's Emergency Medicine, Mount Sinai Community Health, Icahn School of William A. Knight IV, MD, FACEP Saadia Akhtar, MD Michael S. Radeos, MD, MPH Chulalongkorn University, Thailand Medical Director, Emergency Monash University,Clinical Professor, Melbourne, Department of of Cornell University, New York; Dhanadol Rojanasarntikul, MD Professor and Chair, Department Medicine and Neurosurgery, Medical Roosevelt, New York, NY Health System, Icahn School of Medicine at Mount Sinai, New York, NY Associate Professor of Emergency Associate Professor, Department of Associate Professor of Emergency Director, Mount Sinai Hospital, New Management, University of VirginiaAustralia Emergency Medicine, University Research Director, Department of Attending Physician, Emergency of Emergency Medicine, Assistant Director, EM Advanced Practice Stephen H. Thomas, MD, MPH Medicine at Mount Sinai, New York, NY Medicine and Neurosurgery, Medical Emergency Medicine, Associate Dean Medicine, Weill Medical College York, NY Nicholas Genes, MD, PhD Scott Silvers,Medical MD, Center, FACEP Charlottesville, VA of Michigan Medical School; CEO, Emergency Medicine, New York Medicine, King Chulalongkorn Dean, Simulation Education, Provider Program; Associate Medical Professor & Chair, Emergency Giorgio Carbone, MD Director, EM Advanced Practice for Graduate Medical Education, of Cornell University, New York; Associate Professor, Department of Keith A. Marill, MD Associate Professor and Chair, Medical Practice Risk Assessment, Hospital Queens, Flushing, NY Memorial Hospital, Thai Red Cross, Program Director, Emergency University of Florida COM- Director, Neuroscience ICU, University Medicine, HamadAssociate Medical Corp., Editor-In-Chief Research Faculty, Department of DepartmentCalvin of A.Emergency Brown III, Medicine, MD Chief, DepartmentInc., Ann Arbor, of Emergency MI Provider Program; Associate Medical Research Director, Department of Emergency Medicine, Icahn School Ali S. Raja, MD, MBA, MPH Thailand; Faculty of Medicine, Medicine Residency, Mount Sinai Jacksonville, Jacksonville, FL of Cincinnati, Cincinnati, OH Weill Cornell Medical College, Qatar; Emergency Medicine, University Mayo Clinic, Director Jacksonville, of Physician FL ComplianceMedicine, Ospedale Gradenigo, Director, Neuroscience ICU, University Emergency Medicine, New York Kaushal Shah, MD, FACEP of Medicine at Mount Sinai, New John M. Howell, MD, FACEP Chulalongkorn University, Thailand Beth Israel, New York, NY Emergency Physician-in-Chief, Credentialing and Urgent Care Torino, Italy Vice-Chair, Emergency Medicine, of Cincinnati, Cincinnati, OH Gregory L. Henry, MD, FACEP Hospital Queens, Flushing, NY Scott D. Weingart, MD, FCCM Associate Professor, Department of York, NY of Pittsburgh Medical Center, Hamad General Hospital, Corey M.Services, Slovis, MD, Department FACP, FACEP of Emergency Clinical Professor of Emergency Massachusetts General Hospital, Stephen H. Thomas, MD, MPH Clinical Professor, Department of Associate Professor of Emergency Emergency Medicine, Icahn School Pittsburgh, PA Suzanne Y.G. Peeters, MD Scott D. Weingart, MD, FCCM William J. Brady, MD Ali S. Raja, MD, MBA, MPH Doha, Qatar Professor and Chair, Department Medicine, George Washington Boston, MA Professor & Chair, Emergency Emergency Medicine, University Medicine; Director, Division of ED of Medicine at Mount Sinai, New Michael A. Gibbs, MD, FACEP Medicine, Brigham and Women's Attending Emergency Physician, Associate Professor of Emergency Professor of Emergency Medicine Vice-Chair, Emergency Medicine, Professor and Chair, Department Charles V. Pollack Jr., MA, MD, of EmergencyHospital, Medicine, Boston, Vanderbilt MA University, Washington, DC; Director Medicine, Hamad Medical Corp., of Michigan Medical School; CEO, Critical Care, Icahn School of Medicine Edin Zelihic, MDYork, NY Flevo Teaching Hospital, Almere, Robert L. Rogers, MD, FACEP, Medicine; Director, Division of ED and Medicine; Chair, Medical Massachusetts General Hospital, of Emergency Medicine, Carolinas FACEP University Medical Center, Nashville, TN of Academic Affairs, Best Practices, Weill Cornell Medical College, Qatar; even bigger discounts with a group subscription. Visit www.ebmedicine.net/groups to learn more. Medical Practice Risk Assessment, at Mount Sinai, New York, NY Head, Department of Emergency The Netherlands FAAEM, FACP Critical Care, Icahn School of Medicine Emergency Response Committee; Boston, MA Professor and Senior Advisor for Peter DeBlieux, MD Inc, Inova Fairfax Hospital, Falls Emergency Physician-in-Chief, Inc., Ann Arbor, MI Medicine, LeopoldinaEditorial Hospital, Board Medical Center, University of North Ron M. Walls, MD Assistant Professor of Emergency at Mount Sinai, New York, NY Medical Director, Emergency Interdisciplinary Research and Professor of Clinical Medicine, Hugo Peralta,Church, MD VA Hamad General Hospital, Robert L. Rogers, MD, FACEP, Senior Research Editors Schweinfurt,Saadia Germany Akhtar, MD Carolina School of Medicine, Chapel Professor and Chair, Department of Medicine, The University of Management, University of Virginia John M. Howell, MD, FACEP Clinical Trials, Department of Interim Public Hospital Director ChairShkelzen of Emergency Hoxhaj, Services, MD, MPH, MBA Doha, Qatar FAAEM, FACP Associate Professor, Department of Hill, NC Emergency Medicine, Brigham and Maryland School of Medicine, Senior Research Editors Medical Center, Charlottesville, VA Clinical Professor of Emergency Emergency Medicine, Sidney Kimmel of Emergency Medicine Services, Hospital Italiano, Buenos Aires, Assistant Professor of Emergency Aimee Mishler, PharmD, BCPS Emergency Medicine, Associate Dean Women's Hospital, Harvard Medical Chief Medical Officer, Jackson Baltimore, MD Edin Zelihic, MD Medicine, George Washington Emergency Medicine Pharmacist, Steven A. Godwin, MD, FACEP Medical College of Thomas Jefferson Louisiana State University Health Argentina Aimee Mishler, PharmD, BCPS Medicine, The University of School, Boston, MA Memorial Hospital, Miami, FL Calvin A. Brown III, MD University, Washington, DC; Director for Graduate Medical Education, Professor and Chair, Department University, Philadelphia, PA Science Center, New Orleans, LA Alfred Sacchetti, MD, FACEP Head, Department of Emergency Director of Physician Compliance, Maryland School of Medicine, Maricopa Medical Center, Phoenix, AZ Dhanadol Rojanasarntikul, MD Emergency Medicine Pharmacist, of Academic Affairs, Best Practices, Program Director, Emergency of Emergency Medicine, Assistant Assistant Clinical Professor, Medicine, Leopoldina Hospital, Credentialing and Urgent Care Baltimore, MD Michael S. Radeos, MD, MPH Attending Physician, Emergency Maricopa Medical Center, Phoenix, AZ Inc, Inova Fairfax Hospital, Falls Joseph D. Toscano, MD Medicine Residency, Mount Sinai Dean, Simulation Education, Critical Care Editors Department of Emergency Medicine, Schweinfurt, Germany Services, Department of Emergency Chairman, Department of Emergency Associate Professor of Emergency Medicine, King Chulalongkorn Joseph D. Toscano, MD Church, VA Alfred Sacchetti, MD, FACEP Beth Israel, New York, NY University of Florida COM- Thomas Jefferson University, Medicine, Brigham and Women's Medicine, Weill Medical College William A. Knight IV, MD, FACEP Memorial Hospital, Thai Red Cross, Assistant Clinical Professor, Medicine, San Ramon Regional Jacksonville, Jacksonville, FL Philadelphia, PA Chairman, Department of Emergency Hospital, Boston, MA William J. Brady, MD of Cornell University, New York; Associate Professor of Emergency Shkelzen Hoxhaj, MD, MPH, MBA Department of Emergency Medicine, Medical Center, San Ramon, CA Thailand; Faculty of Medicine, Medicine, San Ramon Regional Chief Medical Officer, Jackson Professor of Emergency Medicine Gregory L. Henry, MD, FACEP Research Director, Department of Medicine and Neurosurgery, Medical Thomas Jefferson University, Chulalongkorn University, Thailand Medical Center, San Ramon, CA Peter DeBlieux, MD Memorial Hospital, Miami, FL and Medicine; Chair, Medical Clinical Professor, Department of Emergency Medicine, New York Director, EM Advanced Practice Philadelphia, PA Professor of Clinical Medicine, icon for a closer look atEmergency tables andResponse figures. Committee; Emergency Medicine, University Hospital Queens, Flushing, NY Provider Program; Associate Medical Stephen H. Thomas, MD, MPH Interim Public Hospital Director Medical Director, Emergency of Michigan Medical School; CEO, Director, Neuroscience ICU, University Professor & Chair, Emergency Click on the Ali S. Raja, MD, MBA, MPH of Emergency Medicine Services, Management, University of Virginia Medical Practice Risk Assessment, of Cincinnati, Cincinnati, OH Medicine, Hamad Medical Corp., Louisiana State University Health Vice-Chair, Emergency Medicine, Weill Cornell Medical College, Qatar; Click on the Medical Center, Charlottesville, VA Inc., Ann Arbor, MI Scott D. Weingart, MD, FCCM Science Center, New Orleans, LA Massachusetts General Hospital, Emergency Physician-in-Chief, icon for a closer look at tables and figures. John M. Howell, MD, FACEP Associate Professor of Emergency Calvin A. Brown III, MD Boston, MA Hamad General Hospital, Clinical Professor of Emergency Medicine; Director, Division of ED Director of Physician Compliance, Doha, Qatar Medicine, George Washington Robert L. Rogers, MD, FACEP, Critical Care, Icahn School of Medicine Credentialing and Urgent Care FAAEM, FACP University, Washington, DC; Director at Mount Sinai, New York, NY Edin Zelihic, MD Services, Department of Emergency Assistant Professor of Emergency of Academic Affairs, Best Practices, Head, Department of Emergency Medicine, Brigham and Women's Medicine, The University of Hospital, Boston, MA Inc, Inova Fairfax Hospital, Falls Senior Research Editors Medicine, Leopoldina Hospital, Church, VA Maryland School of Medicine, Aimee Mishler, PharmD, BCPS Schweinfurt, Germany Peter DeBlieux, MD Baltimore, MD Shkelzen Hoxhaj, MD, MPH, MBA Emergency Medicine Pharmacist, Professor of Clinical Medicine, Chief Medical Officer, Jackson Alfred Sacchetti, MD, FACEP Maricopa Medical Center, Phoenix, AZ Interim Public Hospital Director Memorial Hospital, Miami, FL Assistant Clinical Professor, of Emergency Medicine Services, Department of Emergency Medicine, Joseph D. Toscano, MD Louisiana State University Health Thomas Jefferson University, Chairman, Department of Emergency Science Center, New Orleans, LA Philadelphia, PA Medicine, San Ramon Regional Medical Center, San Ramon, CA

Click on the icon for a closer look at tables and figures.

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November 2018 • www.ebmedicine.net 19 Copyright © 2018 EB Medicine. All rights reserved. Physician CME Information Date of Original Release: November 1, 2018. Date of most recent review: October 10, 2018. Termination date: November 1, 2021. Accreditation: EB Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This activity has been October 2016 Volume 18, Number 10 planned and implemented in accordance with the accreditation requirements and policies of the Author ACCME. Julianna Jung, MD, FACEP Optimizing Survival Outcomes Associate Professor and Director of Undergraduate Medical Education, Department of Emergency Medicine, Johns Hopkins University School of For Adult Patients With Medicine, Baltimore, MD Credit Designation: EB Medicine designates this enduring material for a maximum of 4 AMA PRA Peer Reviewers Nontraumatic Cardiac Arrest William J. Brady, MD Professor of Emergency Medicine and Medicine; Chair, Medical Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their Emergency Response Committee; Medical Director, Emergency Abstract Management, University of Virginia Medical Center, Charlottesville, VA Faheem Guirgis, MD, FACEP Assistant Professor of Emergency Medicine, University of Florida Health participation in the activity. Patient survival after cardiac arrest can be improved significantly- Jacksonville, Department of Emergency Medicine, Division of Research, with prompt and effective resuscitative care. This systematic Jacksonville, FL CME Objectives review analyzes the basic life support factors that improve survival- outcome, including chest compression technique and rapid defi Upon completion of this article, you should be able to: Specialty CME: Included as part of the 4 credits, this CME activity is eligible for 4 Trauma CME credits. brillation of shockable rhythms. For patients who are successfully 1. Describe the elements of high-quality basic life support. 2. Discuss the evidentiary basis and current guidelines for advanced resuscitated, comprehensive postresuscitation care is essential. Tar life support interventions. geted temperature management is recommended for all patients 3. Describe essential considerations in postresuscitation care following ACEP Accreditation: Emergency Medicine Practice is approved by the American College of Emergency who remain comatose, in addition to careful monitoring of oxygen- restoration of spontaneous circulation. ation, hemodynamics, and cardiac rhythm. Management of cardiac 4. List modifications to standard resuscitation protocols that may be considered in special resuscitation situations. arrest in circumstances such as pregnancy, pulmonary embolism, Physicians for 48 hours of ACEP Category I credit per annual subscription. opioid overdose and other toxicologic causes, hypothermia, and Prior to beginning this activity,on the back see “Physicianpage. CME Information” coronary ischemia are also reviewed. International Editors Robert Schiller, MD Peter Cameron, MD AAFP Accreditation: This Enduring Material activity, Emergency Medicine Practice, has been Chair, Department of Family Medicine, Academic Director, The Alfred Eric Legome, MD Beth Israel Medical Center; Senior Emergency and Trauma Centre, Chief of Emergency Medicine, Faculty, Family Medicine and Monash University, Melbourne, Daniel J. Egan, MD King’s County Hospital; Professor of Community Health, Icahn School of Australia Associate Professor, Department Clinical Emergency Medicine, SUNY reviewed and is acceptable for credit by the American Academy of Family Physicians. Term of Medicine at Mount Sinai, New York, NY Editor-In-Chief of Emergency Medicine, Program Downstate College of Medicine, Giorgio Carbone, MD Andy Jagoda, MD, FACEP Director, Emergency Medicine Brooklyn, NY Scott Silvers, MD, FACEP Chief, Department of Emergency Professor and Chair, Department of Residency, Mount Sinai St. Luke's Chair, Department of Emergency Medicine Ospedale Gradenigo, Emergency Medicine, Icahn School Roosevelt, New York, NY Keith A. Marill, MD Medicine, Mayo Clinic, Jacksonville, FL Torino, Italy Research Faculty, Department of approval begins 07/01/2018. Term of approval is for one year from this date. Physicians should of Medicine at Mount Sinai, Medical Nicholas Genes, MD, PhD Emergency Medicine, University Corey M. Slovis, MD, FACP, FACEP Suzanne Y.G. Peeters, MD Director, Mount Sinai Hospital, New Emergency Medicine Residency Assistant Professor, Department of of Pittsburgh Medical Center, Professor and Chair, Department York, NY Director, Haga Teaching Hospital, Emergency Medicine, Icahn School Pittsburgh, PA of Emergency Medicine, Vanderbilt University Medical Center, Nashville, TN The Hague, The Netherlands Associate Editor-In-Chief of Medicine at Mount Sinai, New Charles V. Pollack Jr., MA, MD, claim only the credit commensurate with the extent of their participation in the activity. Approved for York, NY FACEP Ron M. Walls, MD Hugo Peralta, MD Kaushal Shah, MD, FACEP Chair of Emergency Services, Hospital Associate Professor, Department of Professor and Senior Advisor for Professor and Chair, Department of Michael A. Gibbs, MD, FACEP Italiano, Buenos Aires, Argentina Emergency Medicine, Icahn School Professor and Chair, Department Interdisciplinary Research and Emergency Medicine, Brigham and of Medicine at Mount Sinai, New of Emergency Medicine, Carolinas Clinical Trials, Department of Women's Hospital, Harvard Medical Dhanadol Rojanasarntikul, MD York, NY Medical Center, University of North Emergency Medicine, Sidney Kimmel School, Boston, MA Attending Physician, Emergency 4 AAFP Prescribed credits. Carolina School of Medicine, Chapel Medical College of Thomas Jefferson Medicine, King Chulalongkorn Editorial Board Hill, NC University, Philadelphia, PA Critical Care Editors Memorial Hospital, Thai Red Cross, Thailand; Faculty of Medicine, Saadia Akhtar, MD Michael S. Radeos, MD, MPH William A. Knight IV, MD, FACEP Steven A. Godwin, MD, FACEP Chulalongkorn University, Thailand Associate Professor, Department of Professor and Chair, Department Assistant Professor of Emergency Associate Professor of Emergency Emergency Medicine, Associate Dean of Emergency Medicine, Assistant Medicine, Weill Medical College Medicine and Neurosurgery, Medical Stephen H. Thomas, MD, MPH for Graduate Medical Education, AOA Accreditation: Emergency Medicine Practice is eligible for up to 48 American Osteopathic Dean, Simulation Education, of Cornell University, New York; Director, EM Midlevel Provider Professor & Chair, Emergency Program Director, Emergency University of Florida COM- Research Director, Department of Program, Associate Medical Director, Medicine, Hamad Medical Corp., Medicine Residency, Mount Sinai Jacksonville, Jacksonville, FL Emergency Medicine, New York Neuroscience ICU, University of Weill Cornell Medical College, Qatar; Beth Israel, New York, NY Hospital Queens, Flushing, NY Cincinnati, Cincinnati, OH Emergency Physician-in-Chief, Gregory L. Henry, MD, FACEP Ali S. Raja, MD, MBA, MPH Scott D. Weingart, MD, FCCM Hamad General Hospital, Doha, Qatar Association Category 2-A or 2-B credit hours per year. William J. Brady, MD Clinical Professor, Department of Professor of Emergency Medicine Vice-Chair, Emergency Medicine, Associate Professor of Emergency Emergency Medicine, University Edin Zelihic, MD and Medicine; Chair, Medical Massachusetts General Hospital, Medicine, Director, Division of ED of Michigan Medical School; CEO, Head, Department of Emergency Critical Care, Icahn School of Medicine Emergency Response Committee; Medical Practice Risk Assessment, Boston, MA Medicine, Leopoldina Hospital, Medical Director, Emergency at Mount Sinai, New York, NY Inc., Ann Arbor, MI Robert L. Rogers, MD, FACEP, Schweinfurt, Germany Management, University of Virginia FAAEM, FACP Medical Center, Charlottesville, VA John M. Howell, MD, FACEP Senior Research Editors Needs Assessment: The need for this educational activity was determined by a survey of medical Clinical Professor of Emergency Assistant Professor of Emergency Calvin A. Brown III, MD Medicine, George Washington Medicine, The University of James Damilini, PharmD, BCPS Director of Physician Compliance, University, Washington, DC; Director Maryland School of Medicine, Clinical Pharmacist, Emergency Credentialing and Urgent Care of Academic Affairs, Best Practices, Baltimore, MD Room, St. Joseph’s Hospital and Services, Department of Emergency Inc, Inova Fairfax Hospital, Falls Medical Center, Phoenix, AZ staff, including the editorial board of this publication; review of morbidity and mortality data from the Alfred Sacchetti, MD, FACEP Medicine, Brigham and Women's Church,Evidence-Based VA Management Assistant Clinical Professor, Joseph D. Toscano, MD Hospital, Boston, MA November 2016 Shkelzen Hoxhaj, MD, MPH, MBA Department of Emergency Medicine, Chairman, Department of Emergency Thomas Jefferson University, Medicine, San Ramon Regional Peter DeBlieux, MD Chief of Emergency Medicine, Baylor Volume 18, Number 11 Professor of Clinical Medicine, CollegeOf of Medicine, Potassium Houston, TX Philadelphia, DisordersPA Medical InCenter, SanThe Ramon, CA Authors CDC, AHA, NCHS, and ACEP; and evaluation of prior activities for emergency physicians. Interim Public Hospital Director of Emergency Medicine Services, John Ashurst, DO, MSc Louisiana State University Health Director of Emergency Medicine Residency Research, Duke Lifepoint Science Center, New Orleans, LA Emergency Department Conemaugh Memorial Medical Center, Johnstown, PA Target Audience: This enduring material is designed for emergency medicine physicians, physician Shane R. Sergent, DO Abstract Department of Emergency Medicine, Conemaugh Memorial Hospital, Johnstown, PA Hypokalemia and hyperkalemia are the most common elec- Benjamin J. Wagner, DO assistants, nurse practitioners, and residents. Department of Emergency Medicine, Conemaugh Memorial Hospital, trolyte disorders managed in the emergency department. The Johnstown, PA diagnosis of these potentially life-threatening disorders is chal Peer Reviewers lenging due to the often vague symptomatology a patient may- Goals: Upon completion of this activity, you should be able to: (1) demonstrate medical decision- Camiron L. Pfennig, MD, MHPE express, and treatment options may be based upon very little Associate Professor of Emergency Medicine, University of South Carolina data due to the time it may take for laboratory values to return. School of Medicine; Emergency Medicine Residency Program Director, This review examines the most current evidence with regard to Greenville Health System, Greenville, SC making based on the strongest clinical evidence; (2) cost-effectively diagnose and treat the most the pathophysiology, diagnosis, and management of potassium Corey M. Slovis, MD, FACP, FACEP Professor and Chair, Department of Emergency Medicine, Vanderbilt disorders. In this review, classic paradigms, such as the use of University Medical Center, Nashville, TN critical presentations; and (3) describe the most common medicolegal pitfalls for each topic sodium polystyrene and the routine measurement of serum CME Objectives magnesium, are tested, and an algorithm for the treatment of Upon completion of this article, you should be able to: potassium disorders is discussed. 1. Identify the etiology of the depletion of potassium in patients with covered. hypokalemia. 2. Identify and manage the etiology and underlying causes of hyperkalemia. 3. Describe the algorithmic management of hypokalemia and hyperkalemia. Objectives: Upon completion of this article, you should be able to: (1) describe the pathophysiology Prior to beginning this activity, see “Physician CME Information” Editor-In-Chief Daniel J. Egan, MD on the back page. Andy Jagoda, MD, FACEP Eric Legome, MD Associate Professor, Department Robert Schiller, MD Professor and Chair, Department of of Emergency Medicine, Program Chief of Emergency Medicine, International Editors Emergency Medicine, Icahn School King’s County Hospital; Professor of Chair, Department of Family Medicine, and epidemiology of electrical and lightning strike injuries, both obvious and occult, (2) determine Director, Emergency Medicine Beth Israel Medical Center; Senior Peter Cameron, MD of Medicine at Mount Sinai, Medical Residency, Mount Sinai St. Luke's Clinical Emergency Medicine, SUNY Faculty, Family Medicine and Academic Director, The Alfred Director, Mount Sinai Hospital, New Roosevelt, New York, NY Downstate College of Medicine, York, NY Brooklyn, NY Community Health, Icahn School of Emergency and Trauma Centre, Nicholas Genes, MD, PhD Medicine at Mount Sinai, New York, NY Monash University, Melbourne, Keith A. Marill, MD Associate Editor-In-Chief Australia the severity of injury based on the mechanism of the electric shock and the physical examination, Assistant Professor, Department of Research Faculty, Department of Scott Silvers, MD, FACEP

Kaushal Shah, MD, FACEP Emergency Medicine, Icahn School Emergency Medicine, University Chair, Department of Emergency Giorgio Carbone, MD Associate Professor, Department of of Medicine at Mount Sinai, New of Pittsburgh Medical Center, Medicine, Mayo Clinic, Jacksonville, FL Chief, Department of Emergency Emergency Medicine, Icahn School York, NY Pittsburgh, PA Corey M. Slovis, MD, FACP, FACEP Medicine Ospedale Gradenigo, of Medicine at Mount Sinai, New Torino, Italy and (3) disposition patients based on the severity of the injury and likelihood of delayed effects. Michael A. Gibbs, MD, FACEP York, NY Charles V. Pollack Jr., MA, MD, Professor and Chair, Department Professor and Chair, Department FACEP of Emergency Medicine, Vanderbilt Suzanne Y.G. Peeters, MD Editorial Board of Emergency Medicine, Carolinas Professor and Senior Advisor for University Medical Center, Nashville, TN Emergency Medicine Residency Medical Center, University of North Interdisciplinary Research and Director, Haga Teaching Hospital, Saadia Akhtar, MD Carolina School of Medicine, Chapel Ron M. Walls, MD Associate Professor, Department of Clinical Trials, Department of Professor and Chair, Department of The Hague, The Netherlands Hill, NC Emergency Medicine, Sidney Kimmel Emergency Medicine, Associate Dean Emergency Medicine, Brigham and Hugo Peralta, MD Discussion of Investigational Information: As part of the journal, faculty may be presenting Medical College of Thomas Jefferson for Graduate Medical Education, Steven A. Godwin, MD, FACEP Women's Hospital, Harvard Medical Chair of Emergency Services, Hospital University, Philadelphia, PA Program Director, Emergency Professor and Chair, Department School, Boston, MA Italiano, Buenos Aires, Argentina Medicine Residency, Mount Sinai of Emergency Medicine, Assistant Michael S. Radeos, MD, MPH Dhanadol Rojanasarntikul, MD Beth Israel, New York, NY Dean, Simulation Education, Associate Professor of Emergency Critical Care Editors University of Florida COM- Attending Physician, Emergency investigational information about pharmaceutical products that is outside Food and Drug Medicine, Weill Medical College William J. Brady, MD William A. Knight IV, MD, FACEP Medicine, King Chulalongkorn Jacksonville, Jacksonville, FL of Cornell University, New York; Professor of Emergency Medicine Associate Professor of Emergency Memorial Hospital, Thai Red Cross, Gregory L. Henry, MD, FACEP Research Director, Department of and Medicine; Chair, Medical Medicine and Neurosurgery, Medical Thailand; Faculty of Medicine, Emergency Medicine, New York Emergency Response Committee; Clinical Professor, Department of Director, EM Midlevel Provider Chulalongkorn University, Thailand Emergency Medicine, University Hospital Queens, Flushing, NY Program, Associate Medical Director, Administration-approved labeling. Information presented as part of this activity is intended solely as Medical Director, Emergency Stephen H. Thomas, MD, MPH Management, University of Virginia of Michigan Medical School; CEO, Ali S. Raja, MD, MBA, MPH Neuroscience ICU, University of Professor & Chair, Emergency Medical Center, Charlottesville, VA Medical Practice Risk Assessment, Vice-Chair, Emergency Medicine, Cincinnati, Cincinnati, OH Inc., Ann Arbor, MI Massachusetts General Hospital, Medicine, Hamad Medical Corp., Scott D. Weingart, MD, FCCM Weill Cornell Medical College, Qatar; Calvin A. Brown III, MD John M. Howell, MD, FACEP Boston, MA Associate Professor of Emergency Emergency Physician-in-Chief, continuing medical education and is not intended to promote off-label use of any pharmaceutical Director of Physician Compliance, Clinical Professor of Emergency Robert L. Rogers, MD, FACEP, Medicine, Director, Division of ED Hamad General Hospital, Doha, Qatar Credentialing and Urgent Care Medicine, George Washington Services, Department of Emergency FAAEM, FACP Critical Care, Icahn School of Medicine University, Washington, DC; Director Edin Zelihic, MD Medicine, Brigham and Women's Assistant Professor of Emergency at Mount Sinai, New York, NY of Academic Affairs, Best Practices, Head, Department of Emergency Hospital, Boston, MA Medicine, The University of Inc, Inova Fairfax Hospital, Falls Medicine, Leopoldina Hospital, product. Maryland School of Medicine, Senior Research Editors Peter DeBlieux, MD Church, VA Baltimore, MD Schweinfurt, Germany James Damilini, PharmD, BCPS Professor of Clinical Medicine, Shkelzen Hoxhaj, MD, MPH, MBA Alfred Sacchetti, MD, FACEP Clinical Pharmacist, Emergency Interim Public Hospital Director Chief of Emergency Medicine, Baylor Assistant Clinical Professor, Room, St. Joseph’s Hospital and of Emergency Medicine Services, College of Medicine, Houston, TX Department of Emergency Medicine, Medical Center, Phoenix, AZ Louisiana State University Health Thomas Jefferson University, Faculty Disclosure: It is the policy of EB Medicine to ensure objectivity, balance, independence, Science Center, New Orleans, LA Joseph D. Toscano, MD Philadelphia, PA Chairman, Department of Emergency Medicine, San Ramon Regional Medical Center, San Ramon, CA transparency, and scientific rigor in all CME-sponsored educational activities. 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Emergency Medicine Practice (ISSN Print: 1524-1971, ISSN Online: 1559-3908, ACID-FREE) is published monthly (12 times per year) by EB Medicine (5550 Triangle Parkway, Suite 150, Norcross, GA 30092). Opinions expressed are not necessarily those of this publication. Mention of products or services does not constitute endorsement. This publication is intended as a general guide and is intended to supplement, rather than substitute, professional judgment. It covers a highly technical and complex subject and should not be used for making specific medical decisions. The materials contained herein are not intended to establish policy, procedure, or standard of care. Copyright © 2018 EB Medicine. All rights reserved. No part of this publication may be reproduced in any format without written consent of EB Medicine. This publication is intended for the use of the individual subscriber only and may not be copied in whole or part or redistributed in any way without the publisher’s prior written permission.