Figure 1. Coronary perfusion pressure before and after drug administration during cardiopulmonary resuscitation (CPR). All data are given as mean +/- SEM. DA, drug administration; CPP, coronary perfusion pressure; solid circles, intravenous vasopressin; solid triangles, endobronchial vasopressin; open circles, endobronchial placebo;*P < 0.05 versus endotracheal placebo;(dagger)P < 0.05 versus endotracheal vasopressin.