Comparison of two protocols for pulseless cardiopulmonary arrest: vasopressin combined with epinephrine versus epinephrine alone.

Introduction: Survival from pulseless cardiac arrest typically is dismal. Some suggest that adding vasopressin to epinephrine as a cardiovascular stimulant can improve outcomes.

Problem: This study compares survival outcomes using epinephrine verses vasopressin and epinephrine in persons with pulseless cardiac arrest.

Methods: This is a retrospective, cohort evaluation of two resuscitative protocols (P1-epinephrine or P2-vasopressin with epinephrine) in a tiered response, community emergency medical service (EMS) with an approximately 100,000 catchment area. Cases are defined as 18 years or older determined to be in pulseless cardiac arrest. Outcomes were survival to emergency department arrival, to 24 hours, and to hospital discharge. Data were entered into Microsoft Office Excel® and processed using Analyze-it® for continuous and categorical data and Epi-Info® for odds ratios with confidence intervals.

Results: There were 204 cases (60.3% males and 39.7% females) who met the inclusion criteria. Thirteen cases received electrical therapy only, and were dropped from analysis, leaving 191 (93.6%) who were included in the study; P1 to 85 (44.5%) and P2 to 106 (55.5%). Younger age was associated with improved survival to discharge home in both protocols, p = 0.003 (95% CI = 0.004-0.010). No difference in survival was noted at the levels of emergency department arrival OR 1.42 (95% CI = 0.73, 2.76) p = 0.26; 24 hour survival OR 0.54 (95% CI = 0.22-1.30) p = 0.133, or discharge home OR = 1.81 (95% CI = 0.49-6.88) p = 0.319.

Conclusions: This study in a community EMS did not demonstrate improved survival with the addition of vasopressin to epinephrine for pulseless cardiac arrest.