Vasopressin-mediated adrenocorticotropin release increases plasma cortisol concentrations during cardiopulmonary resuscitation.

OBJECTIVE: Vasopressin is a possible stimulus for both adrenocorticotropin (ACTH) and endothelin-1 release. The aim of this study was to compare plasma concentrations of ACTH, cortisol, and endothelin-1 after epinephrine or vasopressin administration in an experimental animal model of cardiopulmonary resuscitation (CPR). DESIGN: Prospective, randomized, controlled animal study. SETTING: A university research laboratory. SUBJECTS: Fourteen 12- to 14-wk-old domestic pigs. INTERVENTIONS: After 4 mins of cardiac arrest and 3 mins of external chest compression, the pigs were randomly assigned to receive either 0.045 mg/kg epinephrine (n = 7) or 0.4 units/kg vasopressin (n = 7). At 5 mins after drug administration, defibrillation was attempted. MEASUREMENTS AND MAIN RESULTS: Coronary perfusion pressure, ACTH, cortisol, and endothelin-1 were measured before cardiocirculatory arrest, during CPR before drug administration, and at 90 secs and 5 mins after drug administration. Coronary perfusion pressure was comparable between groups. All seven animals in the vasopressin group survived, but only one pig in the epinephrine group survived (p = .005). ACTH and cortisol concentrations remained unchanged in epinephrine-treated animals, but increased significantly after vasopressin administration and were significantly higher than in epinephrine-treated animals 5 mins after drug administration. Endothelin-1 concentrations remained unchanged during the study period and were comparable between both groups. CONCLUSIONS: Vasopressin is a potent stimulus for ACTH secretion, but does not trigger endothelin-1 release from vascular cells during cardiac arrest and CPR. The increased plasma cortisol concentrations caused by the enhanced ACTH release after vasopressin may be one factor contributing to the improved outcome repeatedly observed with vasopressin in animal models of CPR.

Intraosseous vasopressin improves coronary perfusion pressure rapidly during cardiopulmonary resuscitation in pigs.

OBJECTIVE: Intravenous administration of vasopressin during cardiopulmonary resuscitation (CPR) may be more effective than optimal doses of epinephrine. The main purpose of this study was to determine whether intraosseous vasopressin achieves serum drug levels comparable with intravenous doses during CPR and, additionally, to evaluate the effects of intraosseous vasopressin during CPR. DESIGN: Prospective, randomized laboratory investigation using an established porcine model with instrumentation for measurement of hemodynamic variables, blood gases, and return of spontaneous circulation. SETTING: University hospital laboratory. SUBJECTS: Twelve domestic pigs. INTERVENTIONS: After 4 mins of untreated ventricular fibrillation and 3 mins of CPR, 12 pigs were randomized to be treated with intravenous administration of vasopressin (0.8 unit/kg vasopressin; n = 6) or intraosseous vasopressin (0.8 unit/kg vasopressin; n = 6). Defibrillation was performed 5 mins after drug administration to attempt the return of spontaneous circulation. MEASUREMENTS AND MAIN RESULTS: At both 90 secs and 5 mins after drug administration, intravenous and intraosseous administration of vasopressin resulted in comparable mean (+/-SEM) coronary perfusion pressure (43+/-4 vs. 44+/-3 and 30+/-2 vs. 37+/-2 mm Hg, respectively) and vasopressin plasma concentrations (13,706+/-1,857 vs. 16,166+/-3,114 pg/mL and 10,372+/-883 vs. 8246+/-2211 pg/mL, respectively). All animals in both groups were successfully resuscitated; pigs that received intraosseous vasopressin had a significantly higher (p < .05) mean arterial (92+/-6 vs. 129+/-12 mm Hg) and coronary perfusion pressure (84+/-11 vs. 119+/-11 mm Hg) at 5 mins of return of spontaneous circulation. CONCLUSIONS: Intraosseous vasopressin resulted in comparable vasopressin plasma levels, hemodynamic variables, and return of spontaneous circulation rates as did intravenous vasopressin. Intraosseous vasopressin may be an alternative for vasopressor administration during CPR, when intravenous access is delayed or not available.

[What's new in cardiopulmonary resuscitation? American Heart Association]. / Was ist neu in der kardiopulmonalen Reanimation?

A strong consensus was reached for several changes in the guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC) in the 1992 conference on CPR and ECC held by the Emergency Cardiac Care Committee of the American Heart Association. These new recommendations, together with differing recommendations of the European Resuscitation Council, are described. An unresponsive person with spontaneous respirations should be placed in the recovery position if no cervical trauma is suspected. Compared with endotracheal intubation, other airway-protecting devices such as combination esophageal-tracheal tubes are of minor acceptance. During ventilation, the time for filling the lungs is increased to 1.5-2 s to decrease the likelihood of gastric insufflation. Delivery of i.v. drugs can be enhanced by an i.v. flush of sodium chloride. In endotracheal drug administration, higher doses and drug dilution are recommended. In infants and children up to 6 years of age, the value of intraosseous drug administration is emphasized. For pulseless adult victims, the initial dosage of epinephrine of 1 mg i.v. remains unchanged. For repeat doses, high-dose epinephrine up to 0.1 mg/kg is classified as of uncertain but possible efficacy. For lidocaine, the recommended i.v. dosage is 1.5 mg/kg. Sodium bicarbonate and calcium are not routinely recommended for resuscitation. For atropine, the maximum dose is 0.04 mg/kg. If hypomagnesaemia is present in recurrent and refractory ventricular fibrillation, it should be corrected by administration of 1 to 2 g magnesium sulfate i.v. Thrombolytic agents are classified as useful and effective in acute myocardial infarction and should be administered as early as possible. Glucose-containing fluids are discouraged for resuscitative efforts.