Effects of abdominal Co2 insufflation on renal and hepatic blood flows during acute hemorrhage in anesthetized pigs.

Abstract

To evaluate the consequences of laparoscopy during hemorrhage, we studied the respiratory, renal, and hepatic blood flow changes induced by abdominal Co2 insufflation during severe hemorrhage in anesthetized pigs. Prospective animal study. University research laboratory. Anesthetized and ventilated pigs (n = 18). The right carotid artery was cannulated to measure mean arterial pressure. A pulmonary artery catheter was inserted to measure mean pulmonary arterial pressure and cardiac output. After a midline abdominal incision, three flow probes were positioned around the portal vein, the hepatic artery, and the renal artery to measure portal vein blood flow, hepatic artery blood flow, and renal blood flow. To induce hemorrhage, blood was withdrawn until mean arterial pressure reached 50 mm Hg. Laparoscopy was mimicked by insufflating Co2 until intra-abdominal pressure reached approximately 15 mm Hg. Measurements were collected during hemorrhage, Co2 abdominal insufflation, and the combination of both interventions. Severe pulmonary hypertension and hypercapnic acidosis occurred during abdominal Co2 insufflation. However, the abdominal Co2 insufflation did not aggravate the cardiac output and total hepatic blood flow changes induced by acute hemorrhage, whereas the combination of hemorrhage and abdominal Co2 insufflation markedly altered renal blood flow. These results suggest that renal function must be monitored carefully when performing laparoscopy in trauma patients. In contrast, hepatic perfusion seems well preserved.