Immunotherapy in sepsis

Abstract

Vasopressin (antidiuretic hormone) is a potent vasoconstrictor and improves coronary blood flow when administered during hypovolemia.The purpose of this study was to investigate the effects of vasopressin on myocardial hemodynamics during and after CPR. After 4 min of ventricular fibrillation and 3 min of open-chest CPR, 14 pigs were randomized into 2 groups receiving either 0.8 U/kg vasopressin, or 0.045 mg/kg epinephrine. Myocardial blood flow was measured using radiolabeled microspheres. During CPR, mean coronary perfusion pressure before, 90 sec and 5 min after drug administration was 30±2.2 (SEM), 61±1.7, 46±1.4 mm Hg in the vasopressin group and 29±2.5, 41±2.2, 28±3.6 mm Hg in the epinephrine group (p < 0.001 at 90 sec and 5 min between groups). At the same points in time, mean myocardial blood flow was 61±5, 148±29, 122±22 ml/min/100 gin the vasopressin group and 57±11,. 84±11, 59±9 ml/min/100 g in the epiniphrine group (p < 0.05 at 90 s and 5 min). After a total of 12 min of arrest, including 8 min of CPR,. restoration of spontaneous circulation was possible in all animals. At 5, 15 and 30 min following resuscitation, mean arterial blood pressure was 90±6.5, 84±4.6 and 75± 4.0 mm Hg in the vasopressin group and 64±4.3, 53±4.9 and 56± 3.8 mm Hg in the epinephrine group (p < 0.01 for all 3 comparisons), whereas heart rate, cardiac index, right atrial pressure and pulmonary artery occlusion pressure showed no intergroup differences. Vasopressin was more effective than epinephrine at the doses used, in increasing coronary perfusion pressure and myocardial blood flow. In the first 30 min after restoration of spontaneous circulation, mean arterial blood pressure was significantly higher in the vasopressin-treated animals. As no detrimental effects which could be ascribed to vasopressin were observed, it may be an alternative to adrenergic vasopressors during CPR.