Managing Cardiopulmonary Arrest

1 CE Credit

Christopher Norkus, BS, CVT, VTS (ECC), VTS (Anesthesia)

ardiopulmonary arrest (CPA) is characterized by abrupt, CPCR Stage 1: Basic Life Support complete failure of the respiratory and circulatory systems. Airway management involves extending the patient’s neck to CThe lack of cardiac output and oxygen delivery to tissues straighten the airway and pulling the patient’s tongue forward. (DO2) can quickly cause unconsciousness and systemic cellular The veterinary staff should quickly examine the upper airway death from oxygen starvation. If left untreated, cerebral hypoxia and initiate suctioning, if necessary. All foreign material or vomit results in complete biologic brain death within 4 to 6 minutes of observed in the patient’s mouth should be cleared immediately. CPA.1,2 Therefore, prompt cardiopulmonary cerebral resuscitation If the patient’s airway is fully obstructed, abdominal thrusts (CPCR) is imperative. Veterinary technicians can play a key role and finger sweeps of the pharynx can help dislodge the obstruction. in ensuring that patients receive this treatment. An emergency tracheotomy, which is performed by a veterinarian, may be necessary if the airway obstruction is not immediately Causes and Clinical Signs resolved. Insertion of a large-gauge needle or intravenous (IV) In dogs and cats, common causes of CPA include anesthetic catheter directly into the trachea below the obstruction, along complications; vagal stimulation; hypovolemia; severe trauma, with oxygen administration, can be useful while the tracheotomy such as pneumothorax; unstable cardiac arrhythmias, such as is being performed. In some cases, material fully obstructing the unstable ventricular tachycardia; severe electrolyte disturbances, airway (e.g., a ball) can be manually removed with long hemostats such as hyperkalemia; cardiorespiratory disorders, such as congestive or Doyen intestinal clamps. heart failure, hypoxia, or pericardial tamponade; and debilitating After the patient’s air- or end-stage diseases, such as sepsis or cancer. way has been cleared, an Glossary Potential signs of impending CPA include dramatic changes in endotracheal tube should Hemothorax—accumulation of blood breathing effort, rate, or rhythm (e.g., agonal breathing, decreased be placed. Tube placement in the pleural cavity rate, sudden increased rate); the absence of a pulse; significant should be confirmed and the hypotension (i.e., systolic blood pressure <50 mm Hg [normal: tube secured and cuffed. The Hyperkalemia—an abnormally high >90 to 100 mm Hg]); irregular or inaudible heart sounds; changes patient should then be ven- concentration of potassium ions in in the heart rate or rhythm; change in mucous membrane color tilated with 100% oxygen. the blood (e.g., white or cyanotic); fixed, dilated pupils; distressed vocalizations; Proper ventilation is a and collapse. critical component of BLS. Hypovolemia—a decreased blood Assessment of the patient is crucial if CPA is suspected. Before Based on the most recent volume CPCR is initiated, it is essential to evaluate the patient’s respon- published recommendations, siveness, breathing pattern, and pulse because patients in arrest veterinary patients should Hypoxia—deficiency in the amount of are nonresponsive and apneic, with no detectable pulse. receive 100% oxygen at a rate oxygen reaching the body tissues of 10 to 24 breaths/min.4,5 Pneumothorax—accumulation of air Cardiopulmonary Cerebral Resuscitation In humans, more frequent or gas in the pleural cavity CPCR is initiated in three stages: basic life support (BLS), advanced ventilation has been shown 3 life support (ALS), and postresuscitative care. Adopted from to be significantly detri- Thoracentesis—removal of fluid or air human emergency medicine, BLS involves establishing an open mental because it can result from the chest through a needle or tube and clear airway, providing assisted ventilation, and performing chest in decreased myocardial compressions. These steps are often called the ABCs—airway, and cerebral perfusion.6 Transcutaneous pacing (also called breathing, and circulation. ALS includes advanced care such as Therefore, choosing a lower external pacing)—a temporary means establishing venous access, interpretation of an electrocardiogram rate from the range of 10 of pacing a patient’s heart by delivering (ECG), drug administration, and defibrillation and is typically to 24 breaths/min may be pulses of electric current through the performed by credentialed veterinary technicians, veterinarians, advised; these rates may patient’s chest, which stimulates or both. Postresuscitative care includes intensive monitoring as be reexamined in future contraction of the heart well as cardiovascular and ventilatory support. literature.

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BOX 1. Impedance Threshold Devices

The development of impedance threshold devices (ITDs) has shown promise in both human and animal models.19 The ITD is a small, inexpensive device that is placed on the proximal end of an endotracheal tube during resuscitation to create an increase in negative pressure during the chest-recoil phase of chest compression. An increase in negative pressure creates a vacuum that results in more blood being pulled into the heart and, therefore, more blood output during the next compression. ITDs include a timing light that helps the rescuer ventilate the patient at the proper rate to avoid hyperventilation.

to 90 compressions/min. This has been shown to increase cardiac output.12–14 Based on the “2010 American Heart Association (AHA) Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care”15 and the “2010 International Consensus Figure 1. An Ambu bag. Courtesy of David Liss, RVT, VTS (ECC). on Cardiopulmonary Resuscitation and Emergency Care Science With Treatment Recommendations,”16 rescuers performing chest Veterinary patients can be easily and safely ventilated with an compressions should push hard and fast, allow full chest recoil Ambu bag (FIGURE 1) or bag-valve mask. Using an anesthesia unit after each compression, and minimize interruptions in compressions. can be slow and ineffective because the pop-off valve must be It is critical for chest compressions to be continuous after they opened and closed repeatedly. Peak airway pressure should be have begun. 4 <20 cm H2O. Lack of chest wall motion, poor ventilation, or absence Guidelines for open-chest internal cardiac massage (ICM), of lung sounds should prompt an immediate search for a poorly which is performed by a veterinarian, typically recommend its positioned tube or a severe pleural space disorder, such as pneu- immediate use in all patients >40 lb (18 kg); in patients after 10 mothorax. In these cases, thoracentesis or thoracotomy per- minutes of unsuccessful CPCR, regardless of their size; and in all formed by a veterinarian may be necessary. cases of trauma and/or hemorrhage, such as patients with pneu- Acupuncture has also been used to help treat CPA and respiratory mothorax, hemothorax, or cardiac tamponade.5,17 ICM allows depression.7 Needling the acupuncture point GV26 can help direct visualization of the heart, aortic compression or temporary stimulate respiration and increase cerebral oxygen.8–10 This acupoint ligation, and internal defibrillation. In addition, ICM can increase can be stimulated by inserting a regular 25-gauge needle or acu- cardiac output, blood pressure, coronary perfusion pressure, and puncture needle into the nasal philtrum to a depth of approximately cerebral perfusion pressure compared with closed-chest CPCR and 10 to 20 mm and performing jabs in a hen-pecking motion while has been associated with increased return of spontaneous circu- monitoring for improvement in respiration.8 lation and improved neurologic outcomes in animal models.11,18 The goal of circulatory support during CPCR is to maximize The veterinary staff should regularly assess the effectiveness of myocardial and cerebral perfusion. Chest compressions should be CPCR by palpating for the presence of pulses during compressions performed immediately in patients without a detectable heartbeat. and by using a Doppler ultrasound transducer; however, com- External cardiac massage at a rate of 80 to 120 compressions/min pressions should never be stopped for an assessment. With suf- is recommended,6 but higher rates within that range seem to ficient water-based lubricant, a Doppler transducer can be placed work better.11 Small patients (<15 lb [7 kg]) should receive com- directly over one of the patient’s open eyes. The presence of a pressions directly over the heart (cardiac pump theory), whereas “swooshing” wave sound from the Doppler unit during concurrent larger patients should receive more caudal compressions that are chest compressions can provide a crude estimate of whether for- directed over the widest part of the chest (thoracic pump theory). ward blood flow is reaching the brain. If chest compressions are The cardiac pump theory asserts that arterial blood flow is a not generating adequate forward blood flow, either the patient result of direct compression of the ventricles and, therefore, should be repositioned and the resuscitation technique changed makes sense in small patients with pliable chest walls. Closed-chest to increase intrathoracic pressure (BOX 119) or ICM should be compressions in large patients, however, generally are inadequate considered. in compressing the ventricles. Therefore, the thoracic pump theory, which suggests that forward blood flow in larger patients is the CPCR Stage 2: Advanced Life Support result of a generalized increase in intrathoracic pressure, is used Establishing venous access is important but should never interfere in these patients. Ideally, two technicians should perform inter- with chest compressions or defibrillation. Venous access can be posed abdominal compressions, in which alternate compressions established by using methods such as intraosseous catheter place- of the cranial abdomen and the chest are completed at a rate of 70 ment and venous cutdown, in which a small opening is created in

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BOX 2. Treating Arrhythmias

Treatment of cardiopulmonary arrest depends on the type of arrhythmia, which Routine veterinary treatment includes administration of IV epinephrine at 0.01 to can be effectively differentiated on an electrocardiogram (ECG) only. The two most 0.02 mg/kg q3–5min and IV atropine at 0.04 to 0.05 mg/kg q3–5min.21 The “2010 AHA common arrhythmias in veterinary patients are ventricular asystole and pulseless Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care” do electrical activity (PEA), also known as electromechanical dissociation. Ventricular not advocate the routine use of atropine to manage human PEA because the drug has fibrillation (VF), the most common arrhythmia in humans, is not as common in cats not proved to be of significant benefit for this purpose.15 One dose of IV vasopressin and dogs.24 This may be partly due to the fact that humans commonly experience administered at 0.8 mg/kg is also likely to be beneficial in treating PEA.25 The use of cardiac arrest for different reasons (i.e., myocardial infarction) than veterinary patients. different therapies, such as naloxone, dexamethasone, and calcium, to help treat PEA has been advocated. However, little published information supports regular use of these agents. Ventricular Asystole Asystole, also known as flatline, is the absence of electrical or mechanical activity from Ventricular Fibrillation the heart. A rare P wave may be observed, but no QRS complexes are seen (FIGURE A). In patients with VF, the ECG wave form is erratic and chaotic. No clear P waves, Transcutaneous electrical pacing (Glossary) is immediately initiated in human QRS complexes, or T waves are observed (FIGURE C). patients with asystole, but it has not gained widespread use in veterinary patients. Treating VF involves immediate electrical defibrillation. An initial shock of 3 to Routine veterinary treatment includes IV epinephrine administered at 0.01 to 0.02 5 J/kg is recommended; if the heart rhythm does not respond, two additional shocks, mg/kg q3–5min and IV atropine administered at 0.02 to 0.05 mg/kg q3–5min.21 each at a 50% higher setting than the previous one, should be given in immediate succession. If, after the three progressively higher-voltage shocks, conversion to a stable rhythm is not successful, chest compressions and ventilation are continued for 2 minutes.21 Low-dose epinephrine at 0.01 mg/kg and vasopressin at 0.8 U/kg are then administered. These drugs can improve the likelihood of successful defibrillation. Defibrillation is then resumed at 5 to 10 J/kg, followed by administration of an additional drug, such as amiodarone, Figure A. This ECG of a patient with ventricular asystole is a flatline showing no QRS complexes lidocaine, magnesium chloride, or procainamide. After each new and a rare P wave. drug has been administered, defibrillation is again attempted at the 5- to 10-J/kg setting to restore a normal perfusing rhythm.21 The “2010 AHA Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care” recommend that health care providers continue cardiopulmonary cerebral resuscitation (CPCR) for 2 minutes after initial defibrillation before attempting defibrillation a second time or administering drug therapy in Figure B. This ECG of a patient with PEA looks relatively normal, reflecting the presence of human patients.15 These recommendations are based on the electrical activity. P waves, QRS complexes, and T waves are present. understanding that biphasic defibrillators are readily used in human medicine and have a high initial defibrillation rate. Because biphasic defibrillators are not yet frequently used in veterinary medicine, human literature based on older AHA guidelines may be more applicable to treating dogs and cats. Biphasic defibrillation has been documented in small animal patients and will likely become the preferred method of small Figure C. This ECG of a patient with VF shows the typical erratic pattern with no distinct P waves, animal defibrillation in the future.26 When this more effective T waves, or QRS complexes. Courtesy of Dianne Hudson, RVT, VTS (Anesthesia), Oklahoma State method of defibrillation becomes commonplace, it may make University College of Veterinary Medicine. sense to continue chest compressions for a longer period. It is difficult to successfully treat VF without a defibrillator. The “2010 AHA Guidelines for Cardiopulmonary Resuscitation and Emergency A sharp precordial thump administered to the chest wall may convert VF to a sinus Cardiovascular Care” do not advocate routine use of atropine to manage human rhythm in small patients but is unlikely to be effective in larger patients. Although asystole because the drug has not proved to be of significant benefit for this pharmacologic defibrillation using agents such as potassium chloride, insulin– purpose.15 One dose of IV vasopressin administered at 0.8 U/kg should also be dextrose, and acetylcholine has been suggested, their use is almost never effective. administered early into the arrest.25 Currently, the use of doxapram for respiratory arrest is not recommended. In human preterm infants, the drug has been shown to increase cerebral oxygen Pulseless Electrical Activity demand and, therefore, potentially worsen outcomes.27 The ECG of patients with PEA is relatively normal, reflecting the presence of Sodium bicarbonate should only be administered during CPCR to manage electrical activity in the heart. Consequently, P waves, QRS complexes, and T severe metabolic acidosis diagnosed before the arrest, preexisting hyperkalemia, waves may be observed (FIGURE B). However, in patients with PEA, lack of or metabolic acidosis generated by prolonged CPCR efforts (>10 minutes) and mechanical activity in the heart prevents effective forward perfusion to the body, anaerobic metabolism in hypoxic tissues. The routine use of calcium during resulting in the absence of palpable pulses. (It is important to remember that a CPCR is no longer advised. Its use may be justified in patients with hyperkalemia normal ECG does not mean that a patient is alive; veterinary students are often or hypocalcemia or affected by a calcium channel blocker overdose. Routine use reminded of this to ensure that they look at their patients.) may potentiate cellular damage secondary to ischemia.28

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the skin to allow passage of a needle or cannula into a vein. The Conclusion jugular vein typically yields well to catheterization during CPA After CPA, the success rate for recovery of veterinary patients is and provides the shortest transit time for drugs to reach the heart.20 generally poor.32–34 A 1-week survival rate of <4% has been After venous access has been established, aggressive fluid admin- reported for cats and dogs that received CPCR following full a istration should be considered if hypovolemia existed before the rrest.31 However, functional recovery has been reported in most CPA or if the patient is experiencing blood loss. However, over- animals that survive CPA.35 zealous fluid administration in patients with normal body fluid Based on current research, resuscitation appears to be successful volume may be detrimental. Fluid resuscitation can include in patients that are treated quickly; have a reversible underlying administration of hypertonic saline, crystalloids, colloids, blood disease process, such as anesthetic overdose, upper airway ob- products, and hemoglobin-based oxygen-carrying solutions.20 struction, hemorrhage, or electrolyte abnormalities; and, ideally, If an IV catheter cannot be placed initially, emergency drugs are not in full CPA.24,27,28 (e.g., lidocaine, epinephrine, atropine, vasopressin, naloxone) can be administered through an endotracheal tube.20 Typically, a References long red rubber catheter is inserted down the tube, and drugs are 1. Safar P. Cerebral resuscitation after cardiac arrest: a review. Circulation 1986;74 administered through the catheter. Drug doses administered this (6 pt 2):IV138-153. 2. Safar P. Resuscitation from clinical death: pathophysiologic limits and therapeutic way are normally increased two- to threefold and are followed by potentials. Crit Care Med 1988;16(10):923-941. a small saline “chaser” to ensure successful drug passage into the 3. Pablo LS. Current concepts in cardiopulmonary resuscitation. World Small Anim Vet lungs. For example, the dose for IV atropine is 0.02 mg/kg, but if Assoc World Congr Proc 2003. it is administered through the endotracheal tube, the dose would 4. Kruse-Elliott KT. Cardiopulmonary resuscitation: strategies for maximizing success. be 0.04 to 0.06 mg/kg.21 Vet Med 2001;16(1):51-58. 5. Henik RA. Basic life support and external cardiac compressions in dogs and cats. Intracardiac injection of medication is contraindicated, especially JAVMA 1992;200(12):1925-1931. during closed-chest CPCR. Inaccurate injection and complications, 6. Plunkett SJ, McMichael M. Cardiopulmonary resuscitation in small animal medicine: such as vessel laceration and hemorrhage, are common.22,23 an update. J Vet Intern Med 2008;22(1):9-25. Accurate ECG interpretation, which determines the specific 7. Schoen AM. Veterinary medical acupuncture in critical care medicine. World Small arrhythmia the patient is experiencing (BOX 220–28), is necessary Anim Vet Assoc World Congr Proc 2003. 8. Looney AL. Current thoughts on cardiopulmonary arrest and resuscitation. Atlantic before CPA can be treated. After the type of arrhythmia has been Coast Vet Conf Proc 2001. established, drug administration and defibrillation can be initiated. 9. Janssens L, Altman S, Rogers PA. Respiratory and cardiac arrest under general anaes- If CPA occurs as a result of anesthesia, all anesthetic agents must thesia: treatment by acupuncture of the nasal philtrum. Vet Rec 1979;105(12):273-276. be immediately discontinued and their effects reversed, if possible. 10. Davies A, Janse J, Reynolds GW. Acupuncture in the relief of respiratory arrest. N Z Unfortunately, most patients in CPA cannot be resuscitated Vet J 1984;32:109-110. 11. Kern KB, Sanders AB, Badylak SF, et al. Long-term survival with open-chest cardiac even if CPCR is performed perfectly. End-tidal carbon dioxide massage after ineffective closed-chest compression in a canine preparation. Circulation measurements >15 mm Hg are reportedly associated with higher 1987;75(2):498-503. survival rates.29 Other types of arrhythmia can usually be treated 12. Voorhees WD 3rd, Ralston SH, Babbs CF. Regional blood flow during cardio- until they progress to asystole, unless the patient’s owner declines pulmonary resuscitation with abdominal counterpulsation in dogs. Am J Emerg Med further resuscitation efforts. 1984;2(2):123-128. 13. Babbs CF. Interposed abdominal compression CPR: a comprehensive evidence-based review. Resuscitation 2003;59(1):71-82. CPCR Stage 3: Postresuscitative Care 14. Ralston SH, Babbs CF, Niebauer MJ. Cardiopulmonary resuscitation with interposed Patients that are restored to a perfusing cardiac rhythm commonly abdominal compression in dogs. Anesth Analg 1982;61(8):645-651. experience rearrest—often within minutes to several hours— 15. Field JM, Hazinski MF, Sayre MR, et al. Part 1: executive summary: 2010 American especially if the original cause of the CPA has not been identified. Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation 2010;122(suppl 3):S640-S656. Therefore, resuscitated patients usually require substantial cardio- 16. Hazinski MF, Nolan JP, Billi JE, et al. 2010 international consensus on cardiopulmonary vascular and ventilatory support during the period following resuscitation and emergency care science with treatment recommendations. Resuscita- CPA. Mild hypothermia after resuscitation from CPA decreases tion 2010;81(1; suppl 1):e1–e332. cerebral oxygen demand and has been shown to improve out- 17. Barton L, Crowe DT. Open chest cardiopulmonary resuscitation. In: Bonagura JD, ed. comes in dogs.30 Inducing mild hypothermia in patients could be Kirk’s Current Veterinary Therapy XIII. Philadelphia: WB Saunders; 2000:147-149. 18. Feneley MP, Maier GW, Kern KB, et al. Influence of compression rate on initial success considered a therapeutic option. In human patients, hyperglycemia of resuscitation and 24 hour survival after prolonged manual cardiopulmonary resuscitation has been shown to be associated with worse neurologic outcomes in dogs. Circulation 1988;77(1):240-250. and should, therefore, be avoided after CPA.31 19. Yannopoulos D, Aufderheide TP. Use of the impedance threshold device (ITD). Poor perfusion during CPA may also precipitate brain injury, Resuscitation 2007;75(1):192-193. disseminated intravascular coagulation, gut reperfusion syndrome, 20. Emmerman CL, Pinchak AC, Hancock D, et al. Effect of injection site on circulation times during cardiac arrest. Crit Care Med 1988;16(11):1138-1141. and renal failure. Therefore, intensive monitoring and aggressive 21. Cole S, Otto C, Hughes D. Cardiopulmonary cerebral resuscitation in small animals: supportive care are required to optimize management of blood a clinical practice review. J Vet Emerg Crit Care 2003;13(1):13-23. pressure, cardiac output, oxygenation, ventilation, and vital organ 22. Sabin HI, Coghill SB, Khunti K, McNeill CO. Accuracy of intracardiac injections perfusion.30,31 determined by a post-mortem study. Lancet 1983;2(8358):1054-1055.

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23. Jespersen HF, Granborg J, Hansen U, et al. Feasibility of intracardiac injection of 30. Nozari A, Safar P, Stezoski SW, et al. Mild hypothermia during prolonged cardio- drugs during cardiac arrest. Eur Heart J 1990;11(3):269-274. pulmonary cerebral resuscitation increases conscious survival in dogs. Crit Care Med 24. Rush JE, Wingfield WE. Recognition and frequency of dysrhythmias during cardio- 2004;32(10):2110-2116. pulmonary arrest. JAVMA 1992;200(12):1932-1937. 31. Steingrub JS, Mundt DJ. Blood glucose and neurological outcome with global brain 25. Schmittinger CA, Astner S, Astner L, et al. Cardiopulmonary resuscitation with vaso- ischemia. Crit Care Med 1996;24(5):802-806. pressin in a dog. Vet Anaesth Analg 2005;32(2):112-114. 32. Kass PH, Haskins SC. Survival following cardiopulmonary resuscitation in dogs and 26. Bright JM, Wright BD. Successful biphasic transthoracic defibrillation of a dog with cats. J Vet Emerg Crit Care 1992;2(2):57-65. prolonged refractory ventricular fibrillation.J Vet Emerg Crit Care 2009;193:275-279. 33. Wingfield WE, van Pelt DR. Respiratory and cardiopulmonary arrest in dogs and 27. Dani C, Bertini G, Pezzati M, et al. Brain hemodynamic effects of doxapram in cats: 265 cases (1986-1991). JAVMA 1992;200(12):1993-1996. preterm infants. Biol Neonate 2006;89(2):69-74. 34. de Vos R, Koster RW, de Haan RJ, et al. In-hospital cardiopulmonary resuscitation: 28. van Pelt DR, Wingfield WE. Controversial issues in drug treatment during cardiopul- prearrest morbidity and outcome. Arch Intern Med 1999;159(8):845-850. monary resuscitation. JAVMA 1992;200:1938-1944. 35. Waldrop JE, Rozanski EA, Swanke ED, et al. Causes of cardiopulmonary arrest, 29. Callaham M, Barton C. Prediction of outcome of cardiopulmonary resuscitation from resuscitation management, and functional outcome in dogs and cats surviving cardio- end-tidal carbon dioxide concentration. Crit Care Med 1990;18(4):358-362. pulmonary arrest. J Vet Emerg Crit Care 2004;14(1):22-29.

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1. Ventilatory rates of ______breaths/min are currently c. Patients that experience CPA and have CPCR withheld recommended for veterinary patients in CPA. show no increased morbidity compared with patients that a. 4 to 12 receive immediate CPCR. b. 10 to 24 d. VF is the most common arrhythmia observed in veterinary patients during CPA. c. 30 to 45 d. 60 to 82 7. Mild ______after resuscitation has been shown to improve outcomes in dogs after CPA. 2. Clinical signs of impending CPA include a. hypotension a. a strong pulse. b. hypovolemia b. audible heart sounds. c. hypoxia c. fixed, dilated pupils. d. hypothermia d. significant hypertension. 8. End-tidal carbon dioxide measurements ______3. Which of the following is routinely recommended during have been associated with higher survival rates during CPCR? CPA. a. epinephrine a. <15 cm Hg b. calcium b. >15 cm Hg c. sodium bicarbonate c. <15 mm Hg d. doxapram d. >15 mm Hg

4. The ______vein typically yields well to catheterization 9. In patients with PEA, during CPA and provides the shortest transit time for drugs a. P waves, QRS complexes, and T waves may be observed to reach the heart. on the ECG. a. jugular b. no clear P waves, QRS complexes, or T waves are b. cephalic observed on the ECG. c. saphenous c. a rare P wave may be observed on the ECG, but no clear a. femoral QRS complexes are seen. d. none of the above 5. During CPCR, external cardiac massage should be performed at a rate of ______compressions/min. 10. Treatment of VF involves immediate a. 10 to 60 a. insulin administration. b. 30 to 60 b. thoracentesis. c. 60 to 120 c. IV catheterization. a. 80 to 120 d. electrical defibrillation. 6. Which of the following statements regarding CPA is true? a. Published data suggest that approximately 50% of patients experiencing CPA survive for >1 week after CPCR. b. Functional recovery has been reported in most animals that survive CPA.

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