Emergency Preparedness Case Study: Malignant Hyperthermia CE Darlene Hutton, Bscn, MSN, RN

Case Study

Emergency Preparedness Case Study: Malignant Hyperthermia CE Darlene Hutton, BScN, MSN, RN

he second of this 2012 Case Study 49-year-old man who is sched- higher contracture than that of the Tseries addresses a situation that uled for an abdominoplasty. non-MH muscle. This test requires the person to be present while test- is uncommon in the surgical set- Question 1: What would be ing is occurring, and this test can ting. Without proper recognition and risks associated with MH in this be done only in five designated prompt treatment, the mortality rate patient? can be as high as 80% (Christiansen centers throughout North America a. Any unexplained fever or mus- (Malignant Hyperthermia Associa- & Collins, 2004; Larach, Gronert, Allen, cle rigidity occurring from tion of the United States, 2012a). Brandom, & Lehman, 2010). With anesthesia Intolerance to caffeine may also be prompt recognition and intervention b. A personal history of MH grounds for suspicion for MH but when this emergency does arise, the c. Prior complications during a not a sensitive diagnostic marker mortality rate has been reduced to 5% previous surgery Hutton, 2011; (Table 1). (Rosenberg, Sambuughin, & Dirksen, d. Intolerance to caffeine You are the circulating nurse 2010). Malignant hyperthermia (MH) is in the operating room for this Correct answers: All of the an inherited syndrome that affects 1 of patient. He was induced with mid- above. A prior history of com- azolam, fentanyl, propofol, and 50,000 adults and 1 of 15,000 pediat- plications occurring during or vecuronium bromide, and main- ric patients undergoing anesthetic pro- shortly after anesthesia such as tained with 1%–2% isoflurane in cedures (Christiansen & Collins, 2004; unexplained fever, cola-colored nitrous oxideրoxygen. An hour Rosenberg et al., 2010). In this article, urine, or muscle rigidity may be after induction, his heart rate the reader is exposed to a case of the result of MH crisis. However, increased to 140 beatsրminute, MH and is asked a series of questions the absence of these symptoms his oxygen saturation decreased does not eliminate future MH risk. related to risk assessment, signs and to 88%, and an increase of end- Researchers have reported that symptoms, and nursing responsibilities. tidal carbon dioxide (CO ) to 100 77 of 152 patients who have had 2 mm Hg was observed. You are performing a rou- MH had at least two prior general tine preoperative interview on a anesthetics with no perioperative Question 2: In which order do or postoperative complications these signs most frequently occur Darlene Hutton, BScN, MSN, RN, is a (Larach et al., 2010). A personal or in MH? nurse with 28 years of experience in criti- family history of MH would war- a. Increased heart rate cal care, intensive care, and postanesthetic rant that precautions be in place care units and emergency as an educator, b. Increased end-tidal CO prior to the surgery to avoid an 2 manager, and research nurse. She founded c. Muscle rigidity QRS Educational Services in 1985 and episode. The most sensitive test d. Hyperthermia provides educational workshops, including available for the diagnosis of MH ECG and rhythm interpretation, through- e. Tachypnea is the caffeine-halothane contrac- out Canada. She also provides ACLS as an f. Cyanosis or mottled skin ACLS Course Director throughout Ontario. ture test (Rosenberg et al., 2010). The author reports no conflicts of interest. This test involves comparing fresh Correct sequence: A, E, B, Address correspondence to Darlene Hut- muscle tissue when exposed to caf- C, F, and D (Hommertzheim & ton, BScN, MSN, RN, 2863 Ellesmere Road, Suite 308, Toronto, Ontario, Canada feine and halothane against non- Steinke, 2006). A. Tachycardia (e-mail: [email protected]). MH muscle responses. The diag- is an early sign and occurs in DOI: 10.1097/PSN.0b013e31825a245c nosis of MH is based on obviously 96% of all cases of MH, either

PPSN200207.inddSN200207.indd 8080 55/21/12/21/12 11:1611:16 AMAM TABLE 1 Frequency and Timing of Signs and Symptoms of Malignant predisposing to MH (Rosenberg et Hyperthermia al., 2010). Findings from research conducted on 286 episodes of MH Signs and symptoms Early or late sign Incidence (%) between 1987 and 2006 identified Increased heart rate; ventricular Early 96 that 75% of cases of MH occurred arrhythmia in males (Larach et al., 2010). Tachypnea Early 85 Question 4: What would be imme-

Increased end-tidal CO2 Early 80 diate measures to take when a Muscle rigidity Early 80 patient displays signs and symp- Cyanosis or mottled skin Early 70 toms of MH? Hyperthermia Late 30 a. The circulating nurse initiates MH protocol and calls for sinus tachycardia or ventricular the contracting skeletal muscles additional nursing backup. arrhythmias. E. Tachypnea is an generate excessive heat, resulting b. Additional nursing backup early sign and occurs in 85% in hyperthermia. includes one to prepare dan- of all cases of MH. Tachypnea trolene, one to prepare other Question 3: What are the possible results from the rapid rise of CO medications, and one to pro- 2 causative agents causing MH in and the body’s attempt to reduce vide cooling. this case? this level. B. Increased end-tidal c. Prepare dantrolene. CO is an early sign and occurs d. The surgeon continues the pro- 2 a. Midazolam cedure as soon as the patient in 80% of all cases of MH result- b. Fentanyl has been stabilized. ing in acidosis. In MH, patients c. Propofol e. The anesthesiologist hyperven- will develop both respiratory and d. Vecuronium bromide tilates the patient. metabolic acidoses due to the e. Nitrous oxide buildup of carbon dioxide and f. Isoflurane Correct answers: A. B. The cir- lactic acid. C. Muscle rigidity is culating nurse initiates the MH an early sign and occurs in 80% Correct answer: F. Isoflurane protocol by immediately calling of all cases of MH and results and other volatile inhaled agents for 3 additional nurses: one nurse from excessive amounts of cal- such as desflurane, enflurane, will be responsible to prepare and cium released from intracellular halothane, and sevoflurane are administer dantrolene, another storage sites in the muscle cells. known causative agents in MH. will prepare and administer other F. Flushing of the skin, cyanosis, Succinylcholine is another agent medications, and one will provide or mottling is a sign present in known to potentially cause MH cooling. The circulating nurse 70% of all cases of MH. D. Con- in the vulnerable patient Hutton, will be responsible to assist the trary to the name, hyperthermia 2011; (Table 2). A patient who anesthesiologist in preparing the occurs in only 30% of patients develops MH resulting from necessary laboratory supplies and and is a late sign. In an attempt to exposure to one of these anes- recording. C. Dantrolene sodium reprocess the calcium and return thetic agents likely has one of the reduces muscle tone and metabo- it to storage areas within the cell, two identified genetic mutations lism. The likelihood of any com- plication increases 1.6 times per every 30-minute delay in initiating TABLE 2 Causative and Safe Drugs dantrolene (Larach et al., 2010). Safe preoperative drugs Safe periopera tive drugs Causative drugs E. Hyperventilation with 100% Benzodiazepines: All local anesthetics Succinylcholine oxygen will help offset the rapid Diazepam, lorazepam increase in retained carbon dioxide Narcotics Regional anesthetics Inhaled volatile that leads to respiratory acidosis agents: isoflurane, Hutton, 2011; (Table 3). desflurane, Incorrect answer: D. If the enflurane, halothane, sevoflurane patient exhibits signs of MH prior to initiation of surgery, the pro- Barbiturates General anesthetics: cedure should be cancelled. If benzodiazepines, opioids, barbiturates, propofol, ket- the surgery has started, it should amine, nitric oxide be stopped as soon as possible. Pancuronium If the surgery cannot be abort- ed, the anesthetic agent should Neostigmine and atropine be changed to a nontriggering

PPSN200207.inddSN200207.indd 8181 55/21/12/21/12 11:1611:16 AMAM TABLE 3 Dantrolene Preparation of the onset of an MH crisis. D. Each vial needs to be mixed with ր Dantrolene dose 2.5–4 mg kg between 50 and 60 cc of preserva- Repeated doses 2.5 mg every 4–6 hr for tive-free sterile water. For the ini- 24–48 hr. Once a patient has been treated for tial bolus using 13 vials to recon- 35 hr with IV dantrolene, they may be switched to oral dantrolene until the creatine kinase level stitute 250 mg, a total of 650 ml is trending down, there is no acidosis, and no of sterile water is required. temperature spikes Question 6: For the nurse respon- Each vial of dantrolene 20 mg sible for other medications, what Mix 50-cc preservative-free medications would be anticipated? sterile water Total vials in malignant 36 for immediate preparation a. Sodium bicarbonate hyperthermia cart b. Insulin, IV glucose, calcium Note To expedite reconstitution of chloride dantrolene during an malignant hyperthermia crisis, c. Lasix the manufacturer of dantrolene recommends using d. Amiodarone or lidocaine warmed preservative-free sterile water (37°C–39°C). Correct answers: A, B, C, and D (Fortunato-Phillips, 2000; Hom- one and the breathing circuit Larach et al., 2010; Malignant mertzheim & Steinke, 2006; Larach disconnected from the anesthe- Hyperthermia Association of the et al., 2010; Malignant Hyperther- sia machine (Hommertzheim & United States, 2012b). For this mia Association of the United Steinke, 2006; Larach et al., 2010). patient who weighs 100 kg, the States, 2012). With the rapid rise Extra personnel have arrived. correct dose would range between in metabolic rate leading to an The patient is now experiencing 250 and 400 mg IV push. C. Repeat increased production of heat and

masseter muscle rigidity, cardiac boluses may be given every 5–10 CO2, respiratory and metabolic aci- rhythm remains sinus tachycar- min to a maximum of 10 mgրkg; doses will develop. Anesthesia will dia with premature ventricular 1000 mg for this patient. Follow- hyperventilate the patient to blow

beats and short bursts of non- ing the initial bolus, a mainte- off CO2 and manage the respirato- sustained ventricular tachycar- nance bolus may be given every ry acidosis. To manage the poten- dia, the oxygen saturation is now 4–6 hr for 24–48 hr (Fortunato- tial for metabolic acidosis, an ini-

84%, and end-tidal CO2 has is Phillips, 2000; Hommertzheim & tial dose of IV sodium bicarbonate, being maintained around 90 mm Steinke, 2006; Larach et al., 2010; 1–2 mEqրkg, may be given. Repeat- Hg despite hyperventilation. Malignant Hyperthermia Associa- ed doses may be given on the basis tion of the United States, 2012). of arterial blood gas results. B. IV Question 5: The nurse respon- D. Only preservative-free sterile Insulin, glucose, and calcium chlo- sible for preparing the dantrolene water may be used to reconstitute ride may be ordered to treat hyper- identifies the patient’s weight to dantrolene. kalemia resulting from disruption be 100 kg. Which of the following Incorrect answer: B. One vial of skeletal muscle cell membrane are true of the preparation and contains 20 mg of dantrolene. and leaking of electrolytes, namely administration of dantrolene? The anesthesiologist orders 250 potassium, into the blood stream. a. The anticipated initial dose mg. For this patient who weighs C. As MH progresses, the disrup- will range between 250 and 100 kg, 13 vials of dantrolene tion of skeletal muscle cell mem- 400 mg intravenous (IV) push. would need to be immediately brane leads to leaking of myoglobin b. Immediately prepare one vial prepared: 20 mg multiplied 13 into the blood stream that may and have 36 vials available, in times equals 260 mg. For each obstruct the renal tubules, result- case further doses are needed. subsequent bolus repeated every ing in acute renal failure. To pro- c. Repeated doses may be given 5–10 min, another 13 vials would mote continuous diuresis, Lasix every 5–10 min to a maximum need to be prepared. If the total continues to be the suggested drug dose of 10 mgրkg. maximum dose of 1,000 mg is stocked on the MH cart. The Malig- d. Each vial is to be mixed with reached for this patient, then a nant Hyperthermia Association of 50–60 cc of preservative-free total of 50 vials would be pre- the United States (2012) suggests sterile water. pared over the course of treat- taking mannitol off the MH cart ment. The recommendation from because dantrolene contains 3 g Correct answers: A. The ini- Malignant Hyperthermia Associa- of mannitol in each 20-mg vial tial dose is 2.5–4 mgրkg IV push tion of the United States (2012) (Malignant Hyperthermia Associa- (Fortunato-Phillips, 2000; Hom- is that 36 vials of dantrolene be tion of the United States, 2012). mertzheim & Steinke, 2006; readily available within 5 min D. Cardiac dysrhythmias occur in

PPSN200207.inddSN200207.indd 8282 55/21/12/21/12 11:1611:16 AMAM up to 96% of MH and results groin, and axillae; cooling blanket hyperthermia: A case report and from hyperkalemia. To prevent should be applied to the patient’s review of the literature. The Ameri- worsening of potentially lethal surface. As this case is an abdomi- can Journal of Forensic Medicine and ventricular rhythms, an infusion noplasty, the cooling nurse may Pathology, 25(4), 327–333. of an antiarrhythmic drug such also be required to provide refrig- Fortunato-Phillips, N. (2000). Malig- as amiodarone or lidocaine may erated saline to the scrub nurse for nant hyperthermia. Critical Care Nursing Clinics of North America, be ordered. Correcting the acido- the surgeon to administer into the 12(2), 199–210. sis and hyperkalemia is the best abdominal cavity. Hommertzheim, R., & Steinke, E. intervention to prevent ongoing (2006). Malignant hyperthermia–- ventricular rhythms. The perioperative nurse’s role. Asso- CONCLUSION Question 7: As the nurse respon- ciation of periOperative Registered Nurse Journal, 83(1), 149–168. sible for cooling, what actions The surgery was discontinued and Hutton, D. (2011). Emergency pre- would be anticipated? the patient recovered well in the paredness in the OR, Part I: Malig- a. Prepare to insert a Foley cath- postanesthetic care unit with no nant hyperthermia. Plastic Surgical eter, a nasogastric tube, and a further incidence. Dantrolene, 1 Nursing, 31(1), 23–28. rectal tube as ordered mgրkg, was administered every Larach, M., Gronert, G., Allen, G., Bran- dom, B., & Lehman, E. (2010). Clini- b. Administer cold IV saline as an 4 hr for 48 hr after surgery. All cal presentation, treatment, and com- initial 500–1,000 cc bolus baseline functions returned to plications of malignant hyperthermia c. Administer cold saline for normal. As a surgical team treat- in North American from 1987 to 2006. lavage cooling ing a patient presenting with MH, Anesthesiology, 110(2), 498–507. d. Apply ice to core areas of the each member’s role is vital in opti- Malignant Hyperthermia Association of patient’s body mizing patient outcome. Prompt the United States. (2012a). Directory e. Monitor and record patient recognition of the most frequent of North American malignant hyper- temperature signs alerts the team of a potential thermia testing centers. Retrieved MH emergency. Implementation February 29, 2012, from http:րրwww. Correct answers: All of the ր of an MH protocol and having mhaus.org malignant-hyperthermia- above (Hommertzheim & Steinke, ր ր one assigned nurse to manage the test ing testing-centers 2006). The nurse responsible for Malignant Hyperthermia Association preparation of dantrolene, anoth- cooling management of the patient of the United States. (2012b). FAQs er to manage preparation and will be required to obtain cold about MH: Dantrolene sodium for administration of other medica- saline and ice. Cold saline will be injection. Retrieved February 29, tions, and a third to manage cool- րր ր administered IV, via Foley catheter 2012, from http: www.mhaus.org ing of this patient will maximize ր and rectal and nasogastric tubes mhaus-faqs-healthcare-prof essionals team efforts in treating this life- faqs-about-malignant-hyperthermiaր as ordered. The temperature will threatening condition. Rosenberg, H., Sambuughin, N., & be continuously monitored and Dirksen, R. (2010). Malignant hyper- recorded by the cooling nurse with thermia susceptibility. Gene reviews. the goal being to reach a core body REFERENCES Retrieved November 2, 2010, from temperature of 38ЊC. Ice packs are Christiansen, L., & Collins, K. (2004). http://www.ncbi.nlm.nih.gov/ to be placed to the patient’s neck, Pathologic findings in malignant books/N BK1146/

For more than 77 additional continuing education articles related to surgical, go to NursingCenter.com/CE.

Call for Manuscript Reviewers for Plastic Surgical Nursing

At Plastic Surgical Nursing, we are in need of plastic surgery nurses to review manuscripts for the journal. A reviewer can expect to review up to three manuscripts per year, depending on his or her area of expertise. Now that PSN journal utilizes the Editorial Manager online software, the process is simpliﬁ ed for the reviewer. “Manuscript Reviewer” is a great credential to have on your resume. If you are interested in performing this volunteer service, please contact Tracey Hotta at [email protected]

PPSN200207.inddSN200207.indd 8383 55/21/12/21/12 11:1611:16 AMAM