The use of arginine vasopressin during cardiopulmonary resuscitation. An analysis of experimental and clinical experience and a view of the future

Abstract

The risks and benefits of epinephrine given during cardiopulmonary resuscitation (CPR) are controversially discussed. Animal experiments revealed beta-receptor-mediated adverse effects of epinephrine such as increased myocardial oxygen consumption, ventricular arrhythmia, ventilation-perfusion defects, and cardiac failure in the postresuscitation phase. In clinical studies, high-dose vs. standard-dose epinephrine was unable to improve resuscitation success. During CPR in patients, endogenous arginine vasopressin (AVP) levels were increased and surviving vs. non-surviving patients had significantly higher AVP levels. This may indicate that the human body discharges AVP during life-threatening situations as an additional vasopressor to catecholamines in order to maintain cardiocirculatory homeostasis. In different experimental CPR models, AVP compared with epinephrine given during CPR significantly improved vital organ blood flow, coronary perfusion pressure, resuscitability, and long-term survival. During prolonged CPR with repeated drug administration, AVP but not epinephrine maintained coronary perfusion pressure on a level that ensured return of spontaneous circulation. Also, AVP can be administered successfully in the intravenous dose into the endobronchial tree, and also intraosseously. When given during CPR, AVP induces a transient splanchnic hypoperfusion, and an increase in systemic vascular resistance, both of which normalized spontaneously; furthermore, an oligo-anuric state was not observed. In two clinical studies, AVP vs. epinephrine improved 24-h survival during out-of-hospital CPR, and comparable CPR outcome during in-hospital CPR. The new CPR guidelines of both the American Heart Association and the European Resuscitation Council assign a given CPR intervention into classes of recommendation [class 1 (definitely recommended), class 2 A (intervention of choice), class 2B (alternative intervention), class X (neutral), or class 3 (not recommended)]. For CPR of adults with shock-refractory ventricular fibrillation, 40 units AVP or 1 mg epinephrine is recommended (class 2B); patients with asystole or pulseless electrical activity should be resuscitated with epinephrine. AVP is not recommended for adult cardiac arrest patients with asystole or pulseless electrical activity; or pediatric cardiac arrest patients due to a lack of clinical data. Until definitive data about AVP vs. epinephrine effects during CPR are available, the present state of knowledge should be interpreted that two vasopressors are available for use instead of one.