eMedicine Specialties > Emergency Medicine > Cardiovascular
Asystole: Treatment & Medication
Updated: Jul 7, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
- Multimedia
Treatment
Prehospital Care
- The only 3 drugs recommended or acceptable by the American Heart Association (AHA) for adults in asystole are epinephrine, vasopressin, and atropine. In spite of full vagolytic doses of atropine (0.03 mg/kg) and high-dose epinephrine (0.20 mg/kg), or the use of vasopressin 40 units (U), few patients survive to leave the hospital neurologically intact. Atropine is no longer recommended in young children and infants in asystole but can be considered in adults with slow pulseless electrical activity (PEA) rhythms.
- If spontaneous circulation has not been restored, administering vasopressin 40 U IV for the first 2 doses or followed by epinephrine given at the physician's discretion has recently showed some promising if mixed results.
- A recent study showed that more patients survived to hospital discharge, although the neurologic status of the patients at discharge was not clearly stated. Further analysis has suggested a tendency for a worse neurological outcome in those who received vasopressin, many of whom ended up in a vegetative state. The number of patients with asystole in the study was 528. Of those, 12 patients in the vasopressin group survived to discharge compared with 4 in the standard therapy group. In this study, the odds ratio stated may not be statistically significant. The study also showed a nonstatistically significant trend toward worse results for ventricular fibrillation (VF) and PEA.5
- Gueugnaiud and colleagues found in a larger comparison study between epinephrine alone and epinephrine with vasopressin 40 units that there were no significant differences between groups in terms of return of spontaneous circulation, survival to hospital discharge, 1 year survival, or good neurological recovery among survivors at hospital discharge.6
- The advanced cardiac life support (ACLS) 2005 guidelines allow vasopressin 40 IU IV as a one-time dose treatment option in VF and asystole. It can be given either before epinephrine or after the first dose of epinephrine.
- Transcutaneous pacing (TCP), even when used immediately, has not altered meaningful survival (ie, functional lifestyle) significantly. However, when no metabolic deficit exists, such as in a cardiac arrest preceded by a conduction or impulse generation disorder (ie, primary asystole), immediate use of TCP may be lifesaving.
Emergency Department Care
Mainstays of ED treatment are providing oxygenation and ventilation via endotracheal intubation and circulation via CPR, attempts at transcutaneous or transvenous pacing (that have some small potential to be fruitful in primary asystole that has just occurred), and administration of pharmacologic agents.
- A case has been reported of a long but successful resuscitation from asystole of a patient who was hyperkalemic secondary to renal failure. The treatment included calcium chloride to reverse the physiologic effects of hyperkalemia and insulin and glucose to lower serum potassium levels. This cannot be recommended routinely for all cases of asystolic arrest.
- Electrical defibrillation should not be applied indiscriminately to the patient in asystole. This is not only fruitless, but also detrimental, eliminating any possibility of recovering a rhythm. Asystole following electrical defibrillation has an even worse outcome than that in a patient whose first documented rhythm was asystole. One caution is that, following defibrillation, a brief spurious asystole can occur using manual monitoring through the defibrillator paddles. This does not occur with the rhythm monitoring leads or hands-off monitor pads. If not taken into consideration, it could lead to a delay in defibrillation, when indeed VF is present.
Medication
Parasympathetic influences during cardiopulmonary arrest have not been elucidated fully, and the clinical benefits of atropine have yet to be confirmed. Atropine can be used for asystole, but the AHA now states that its use should be considered. High-dose epinephrine (0.20 mg/kg) may improve the hemodynamics of CPR, thereby increasing the rate of return to spontaneous circulation; however, it has not been demonstrated to influence the final clinical outcome. Therefore, these doses no longer are recommended for children or adults. Adenosine antagonists, such as aminophylline, have been investigated but have not been shown to be clinically useful.
Anticholinergic agents
The goal in using these agents is to enhance sinoatrial activity and to improve conduction through the SA or AV node by reducing vagal tone via muscarinic receptor blockade. This is effective only if the site of block is within the SA or AV node. For patients with infranodal block, this therapy is ineffective. It may increase a Mobitz II second-degree block to a higher degree of block or a third-degree block.
Atropine (Atropair, Isopto, Atropisol)
Parasympatholytic agent used to eliminate vagal influence on SA and AV nodes. Not effective for infranodal third-degree heart block.
Adult
1 mg IV/IO, may repeat dose up to 3 mg total, or 0.03 mg/kg, which is completely vagolytic
If no IV/IO access is available, administer 2 or 2.5 mg via an endotracheal tube (ET); this is a less reliable method and should only be used as a last resort; dose should be followed (a "flush") with 5 mL of normal saline flush and 5 ventilations should be provided; a minimum dose of 0.1 mg IV/IO should be given to avoid centrally mediated paradoxical parasympathomimetic effect
Pediatric
Pediatric bradyasystolic arrest: Not recommended
Symptomatic bradycardia with a pulse unresponsive to oxygen and fluids: 0.02 mg/kg IV/IO
Children: 0.1 mg IV minimum dose; not to exceed 0.5 mg; maximum total dose 1 mg
Adolescents: 0.1 mg IV minimum dose; not to exceed 1 mg; maximum total dose 2 mg
If no IV or IO access exists, give 0.03 mg/kg ET; the same holds for this route as stated above when applied to pediatrics
None for this indication
None when indicated for symptomatic sinus bradycardia or Mobitz type I second-degree heart block; contraindicated in Mobitz type II second-degree heart block; generally not effective for infranodal third-degree heart block
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Adds to tachydysrhythmia if a rhythm resumes, especially when used with sympathomimetic agents; may potentially lower the VF threshold (theoretical and only an issue if perfusing rhythm present)
Adrenergic agonists
These agents can produce constriction of skeletal and vascular muscle.
Epinephrine (Adrenaline)
Considered the single most useful drug in cardiac arrest. Used to increase coronary and cerebral blood flow during CPR. May enhance automaticity during asystole. Can be used for bradycardia in adult and pediatric patients.
Adult
1 mg IV/IO; 2-2.5 mg ET if not given IV/IO; range was 0.01-0.20 mg/kg depending on standard-dose or high-dose epinephrine protocols (high doses no longer recommended by AHA)
Pediatric
0.01 mg/kg IV/IO; alternative, 0.10 mg/kg ET if no IV/IO access (high-dose [0.20 mg/kg] no longer recommended by AHA)
None for this indication
None for this indication
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
May result in tachydysrhythmia if rhythm resumes; this is additive to effects of atropine or other sympathomimetic agents
Vasopressin (Pitressin)
Has vasopressor and ADH activity. Increases water resorption at distal renal tubular epithelium (ADH effect) and promotes smooth muscle contraction throughout vascular bed via stimulation of V1 receptors, thus the vasopressor effect. Vasoconstriction is increased in splanchnic, portal, coronary, cerebral, peripheral, pulmonary, and intrahepatic vessels.
Adult
40 IU IV once, although some studies suggest a repeat dose of 40 IU (not an AHA recommendation)
Pediatric
Not established
None for this indication
None for this indication
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
May result in hypertension and bradycardia if a rhythm resumes
More on Asystole |
| Overview: Asystole |
| Differential Diagnoses & Workup: Asystole |
 Treatment & Medication: Asystole |
| Follow-up: Asystole |
| Multimedia: Asystole |
| References |
| Further Reading |
| « Previous Page | Next Page » |
References
Gray WA, Capone RJ, Most AS. Unsuccessful emergency medical resuscitation--are continued efforts in the emergency department justified?. N Engl J Med. Nov 14 1991;325(20):1393-8. [Medline].
Engdahl J, Bang A, Lindqvist J, Herlitz J. Can we define patients with no and those with some chance of survival when found in asystole out of hospital?. Am J Cardiol. Sep 15 2000;86(6):610-4. [Medline].
Reuters Health Information 2009. Cardiac resuscitation more effective in children and teens than in adults. Medscape. Available at http://www.medscape.com/viewarticle/589311. Accessed March 11, 2009.
Cummins RO, Austin D Jr. The frequency of 'occult' ventricular fibrillation masquerading as a flat line in prehospital cardiac arrest. Ann Emerg Med. Aug 1988;17(8):813-7. [Medline].
Wenzel V, Krismer AC, Arntz HR, et al. A comparison of vasopressin and epinephrine for out-of-hospital cardiopulmonary resuscitation. N Engl J Med. Jan 8 2004;350(2):105-13. [Medline].
Mattu A. Should a moratorium be placed on the use of vasopressin for cardiac arrest. Posted February 2, 2009. Medscape. Available at http://www.medscape.com/viewarticle/587325?src=mp&spon+45&uac+120753HX. Accessed February 9, 2009.
Bernard SA, Gray TW, Buist MD, Jones BM, Silvester W, Gutteridge G, et al. Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med. Feb 21 2002;346(8):557-63. [Medline].
American Heart Association. Guidelines for cardiopulmonary resuscitation and emergency cardiac care. Emergency Cardiac Care Committee and Subcommittees, American Heart Association. Part I. Introduction. JAMA. Oct 28 1992;268(16):2171-83. [Medline].
Barthell E, Troiano P, Olson D, et al. Prehospital external cardiac pacing: a prospective, controlled clinical trial. Ann Emerg Med. Nov 1988;17(11):1221-6. [Medline].
Bayes de Luna A, Coumel P, Leclercq JF. Ambulatory sudden cardiac death: mechanisms of production of fatal arrhythmia on the basis of data from 157 cases. Am Heart J. Jan 1989;117(1):151-9. [Medline].
Billi JE, Zideman DA, Eigel B, et al. Conflict of interest management before, during, and after the 2005 International Consensus Conference on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations. Resuscitation. Nov-Dec 2005;67(2-3):171-3. [Medline].
Bognolo DA, Rabow FI, Vijayanagar RR, Eckstein PF. Traumatic sinus node dysfunction. Ann Emerg Med. Jun 1982;11(6):319-21. [Medline].
Comess KA, DeRook FA, Russell ML, et al. The incidence of pulmonary embolism in unexplained sudden cardiac arrest with pulseless electrical activity. Am J Med. Oct 1 2000;109(5):351-6. [Medline].
ECC Committee, Subcommittees and Task Forces of the American Heart Association. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. Dec 13 2005;112(24 Suppl):IV1-203. [Medline].
Gold RS, Pollard Z, Buchwald IP. Asystole due to the oculocardiac reflex during strabismus surgery: a report of two cases. Ann Ophthalmol. Dec 1988;20(12):473-5, 477. [Medline].
Herlitz J, Ekstrom L, Wennerblom B, et al. Effect of bystander initiated cardiopulmonary resuscitation on ventricular fibrillation and survival after witnessed cardiac arrest outside hospital. Br Heart J. Nov 1994;72(5):408-12. [Medline].
Lindholm DJ, Campbell JP. Predicting survival from out-of-hospital cardiac arrest. Prehospital Disaster Med. Apr-Dec 1998;13(2-4):51-4. [Medline].
Locatelli ER, Varghese JP, Shuaib A, Potolicchio SJ. Cardiac asystole and bradycardia as a manifestation of left temporal lobe complex partial seizure. Ann Intern Med. Apr 6 1999;130(7):581-3. [Medline].
Mader TJ, Smithline HA, Gibson P. Aminophylline in undifferentiated out-of-hospital asystolic cardiac arrest. Resuscitation. Jun 1999;41(1):39-45. [Medline].
Marill KA, Williamson S. Cardiac arrest: current concepts, controversies, and evidence. Emergency Medicine Practice. Nov 2002;4(11):1-24.
Moonie GT, Rees DL, Elton D. The oculocardiac reflex during strabismus surgery. Can Anaesth Soc J. Nov 1964;11:621-32. [Medline].
Niemann JT, Cairns CB. Hyperkalemia and ionized hypocalcemia during cardiac arrest and resuscitation: possible culprits for postcountershock arrhythmias?. Ann Emerg Med. Jul 1999;34(1):1-7. [Medline].
Niemann JT, Stratton SJ, Cruz B, Lewis RJ. Outcome of out-of-hospital postcountershock asystole and pulseless electrical activity versus primary asystole and pulseless electrical activity. Crit Care Med. Dec 2001;29(12):2366-70. [Medline].
Ornato JP, Peberdy MA. The mystery of bradyasystole during cardiac arrest. Ann Emerg Med. May 1996;27(5):576-87. [Medline].
Perers E, Abrahamsson P, Bang A, et al. There is a difference in characteristics and outcome between women and men who suffer out of hospital cardiac arrest. Resuscitation. Apr-May 1999;40(3):133-40. [Medline].
Pitetti R, Glustein JZ, Bhende MS. Prehospital care and outcome of pediatric out-of-hospital cardiac arrest. Prehosp Emerg Care. Jul-Sep 2002;6(3):283-90. [Medline].
Resuscitation Council [UK]. Spurious asystole when using manual defibrillators and monitoring through the defibrillator paddled. Resusitation Council [UK]. 2002;1-2.
Richman PB, Nashed AH. The etiology of cardiac arrest in children and young adults: special considerations for ED management. Am J Emerg Med. May 1999;17(3):264-70. [Medline].
Savage DD, Castelli WP, Anderson SJ, Kannel WB. Sudden unexpected death during ambulatory electrocardiographic monitoring. The Framingham Study. Am J Med. Jan 1983;74(1):148-52. [Medline].
Sayegh AJ, Swor R, Chu KH, et al. Does race or socioeconomic status predict adverse outcome after out of hospital cardiac arrest: a multi-center study. Resuscitation. Apr-May 1999;40(3):141-6. [Medline].
Starfield B. Continuous confusion?. Am J Public Health. Feb 1980;70(2):117-9. [Medline].
Stiell IG, Wells GA, Field B, et al. Advanced cardiac life support in out-of-hospital cardiac arrest. N Engl J Med. Aug 12 2004;351(7):647-56. [Medline].
Vukov LF, White RD. External transcutaneous pacemakers in prehospital cardiac arrest. Ann Emerg Med. May 1988;17(5):554-5. [Medline].
Young KD, Gausche-Hill M, McClung CD, Lewis RJ. A prospective, population-based study of the epidemiology and outcome of out-of-hospital pediatric cardiopulmonary arrest. Pediatrics. Jul 2004;114(1):157-64. [Medline].
Further Reading
Clinical guidelines
Advanced life support. In: 2005 International Consensus Conference on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Circulation 2005 Nov 29;112(22 Suppl):III25-54. [601 references]
Keywords
flat line, asystole, cardiac arrest, heart attack, cardiac standstill, pulseless electrical activity, PEA, primary asystole, secondary asystole, bradyasystolic rhythm, bradydysrhythmia, bradyasystole, asystolic cardiopulmonary arrest, asystolic cardiac arrest
