Experimental Studies on Extracorporeal Circulation by Rygg-Kyvsgaard Heart-Lung Machine, Hartman`s Solution Prime,and Moderate Hypothermia: [Part I]

Hartmann`s 용액으로 충진한 혈희석 체외순환에 관한 실험적 연구: (1보: 심폐기 Rygg-Kyvsgaard 의 혈산화와 혈압 및 혈액상에 미치는 영향)

Total body perfusion using Rygg-Kyvsgaard Heart-Lung-Machine, Mark IV, Polystan was attempted in the dogs by the hemodilution method with total prime of buffered Hartman's solution and under hypothermia. The first of all, the functions of Rygg--Kyvsgaard Heart-Lung-Machine and the effects of the hemodilution perfusion by buffered Hartman's solution was studied. At the same time the changes of blood pressure, oxygen consumption, and influence on the blood pictures were observed before, during, and in 1-3 days after perfusion. Hemodilution rates were the average 74. 22cc/Kg(the ranges of 67 to 81 cc/Kg) and perfusion flow rates were maintained in the mean 62. 6cc/Kg/min., Although it was possible to check up to 87 cc/ Kg/min. The total body perfusion continued for 60-80 minutes. Hypothermia was employed between $36^{\circ}C$ and $32^{\circ}C$ of the rectal temperature. Arterial pressure was ranged approximately between 68mmHg and 149mmHg, but generally, it was maintained over 80mmHg. Venous pressure was measured between 6.5cm $H_2O$and 11.5cm $H_2O$. Optimum oxygenation can be expected when oxygen flow into the disposable bubble oxygenator was maintained approximately at 3.5 L/min .. Inthis way, the oxygen contents were measured in the mean value of 13.11${\pm}$O.56 vol. % of arterial blood and 8.67+1.08 vol.% of venous blood(P${\pm}$0.86 vol.% in arteriovenous oxygen difference and 2. 97${\pm}$0.62cc/Kg in oxygen consumption were calculated. According to these dates, it is as plain as pikestaff that excellent oxygenation and good tissue perfusion was accomplished. Erythrocyte, hemoglobin and hematocrit were decreased about 38% during extracorporeal circulation and these were not recovered until 1-3 days after perfusion. These decrease was resulted from relatively high degree of hemodilution rate and no blood transfusion to compensate during these experimental studies. The platelets were also decreased about 76% during perfusion, but on the contrary, it was increased progressively after perfusion and in 1-3 days after perfusion was returned to the control level. Leucocyte were also decreased during perfusion, but it was increased progessively after perfusion and in 1-3 days after perfusion exceed the control level. This increase was resulted from postoperative infection of the wound, but its analysis were not changed significantly.