The effects of vasoactive drugs on hepatic blood flow changes induced by CO2 laparoscopy: An animal study

Laparoscopic surgery is associated with systemic and splanchnic hemodynamic alterations. Recent data suggest that small-dose dobutamine may attenuate the reduction in splanchnic blood flow associated with increments in intraa bdominal pressure. We conducted this study to analyze the effects of dopami ne and dobutamine on the hepatic circulation in this setting. Twenty-one pi gs were anesthetized and mechanically ventilated. A flow-directed pulmonary artery and carotid artery catheters were inserted. Perivascular flowprobes were placed around the main hepatic artery and the portal vein. CO2 was in sufflated. into the peritoneal cavity to reach an intraabdominal pressure o f 15 mm. Hg. After 60 min, animals received dopamine (5 mug . kg(-1) . min( -1); n = 8), dobutamine (5 mug . kg(-1) . min(-1); n = 8), or saline (n = 5 ) for 30 min. Pneumoperitoneum induced significant increases in heart rate, mean arterial pressure, and systemic vascular resistance, with decreases i n cardiac output and hepatic artery and portal vein blood flows. Dobutamine infusion, in contrast to dopamine, corrected, at least in part, cardiac ou tput, systemic vascular resistance, and hepatic artery blood flow alteratio ns, but neither drug restored total hepatic blood flow.