Effect of small-dose dopamine on mesenteric blood flow and renal function in a pig model of cardiopulmonary resuscitation with vasopressin

Vasopressin (antidiuretic hormone) seems a promising alternative to epineph rine for cardiopulmonary resuscitation (CPR) in cardiac arrest victims,medi ating a pronounced blood flow shift toward vital organs. We evaluated the E ffects of small-dose dopamine on splanchnic blood flow and renal function a fter successful resuscitation with this potent vasoconstrictor in an establ ished porcine CPR model. After 4 min of cardiac arrest, and 3 min of CPR, a nimals received 0.4 U/kg vasopressin and were continuously infused with eit her dopamine 4 mu g.kg(-1).min(-1) (n = 6),or saline placebo (n = 6). Defib rillation was performed 5 min after drug administration; all animals were o bserved for 6 h after return of spontaneous circulation. During the postres uscitation phase, average mean rt SD superior mesenteric artery blood flow was significantly (P = 0.002) higher in the dopamine group compared with th e placebo group (1185 +/- 130 vs 740 +/- 235 mL/min), whereas renal blood f low was comparable between groups (255 +/- 40 vs 250 +/- 85 mL/min). The me dian calculated glomerular filtration rate had higher values in the dopamin e group (70-120 mL/min) than in the placebo group (40-70 mL/min; P = 0.1 at 0 min and P = 0.08 at 360 min), We conclude that small-dose dopamine admin istration may be useful in improving superior mesenteric artery blood flow and renal function after successful resuscitation with vasopressin. Implica tions: Long-term survival after cardiac arrest may be determined by the abi lity to ensure adequate organ perfusion during cardiopulmonary resuscitatio n and in the postresuscitation phase. Ln this regard, small-dose dopamine i mproved postresuscitation blood flow to the mesenteric bed when vasopressin was used as an alternative vasopressor in an animal model of cardiac arres t.