A Study on Splanchnic Hemodynamics and Metabolism of Hormone, Lactate and Pyruvate during Pulsatile Extracorporeal Circulation

Effects of pulsatile perfusion on hemodynamics and metabolism of the splanchnic organs were investigated in adult mongrel dogs. Pulsatile perfusion was performed with a Pulsatile Bypass Pump (PBP) and blood flow was measured with an ultrasonic transit time flowmeter, a newly developed apparatus, capable of accurate measurement of both quick and slow blood flow. For hemodynamics, pulsatile and nonpulsatile total perfusion groups were compared, with regards to flow rate of 60 ml/kg/min, 80ml/kg/min and 100ml/kg/min under cardiac arrest. For metabolism, comparsion was made between the two groups at flow rate of 80ml/kg/min, with regards to blood sugar, angiotensin 2, plasma renin activity, catecholamine, aldosterone, insulin, pancreas-glucagon, total glucagon, lactate extraction ratio, pyruvate extraction ratio and excess lactate. Difference in hemodynamic state between both groups was noted in only those animals perfused at flow rate of 100 ml/kg/min, with significantly higher renal and portal blood flow in the pulsatile group. As for the differences in metabolism, the pulsatile group showed significantly lower plasma renin activity and adrenalin of renal blood, higher insulin pancreas-glucagon molar ratio of portal blood and more aerobic splanchnic metabolism. It was confirmed that pulsatile perfusion with PBP provides splanchnic circulation and metabolism in near-physiological state during extracorporeal circulation.