[The influence of arterial partial pressure of co2 and of the arterial value of ph on endogenous catecholamines during extracorporal circulation in regard to oxygen consumption of the whole body (author's transl)].

Ten patients with coronary heart diseases were studied during total hypothermic extracorporal circulation relating changes of the endogenous catecholamines epinephrine and nor-epinephrine to arterial partial pressure of CO2 and to the arterial value of pH. Both of the catecholamines increased significantly during respiratory or metabolic acidosis whereas respiratory or metabolic alkalosis was accompanied by significantly lower catecholamine levels in blood. The changes in total peripheral resistance due to the endogenous blood levels of catecholamines depended proprotionally. Total peripheral resistance increased significantly due to increasing arterial level of both of the catecholamines. The results are discussed in consideration of oxygen consumption of the whole body during extracorporal circulation. It is known that the decrease of oxygen consumption of the whole body due to acidosis and due to an increased total peripheral resistance is accompanied by high catecholamine levels in blood. Increased hypothermic sympatho-adrenal activity during extracorporal circulation should not in any case cause in increase of oxygen consumption of the whole body.