Cardiac Preservation Utilizing Hyperbaric Oxygen and Hypothermia

¹ Department of Surgery, University of Missouri Medical Center

Hearts are removed from the donor animal utilizing hypothermia of 28°C. and ligation of the inferior and superior vena cava, pulmonary veins, pulmonary artery, and the aorta. The average time for removal has been approximately four minutes. These hearts are then placed in the hyperbaric oxygen chamber which is maintained at a temperature of 2°C. Hyperbaric oxygen pressure of 3 atmospheres is then established in the chamber, and the hearts remain in the chamber for a period of 24 hours. Upon removal from the chamber the hearts are placed in the neck of the recipient animal by the technique of Marcus, Wong and Luisada.³ The media used in the chamber has been either lactate Ringer's or normal saline fortified with glucose. The temperature has been maintained at 2° C. After circulation has been reinstituted in the heart by implantation into the neck with the aorta anastornosed to the distal carotid artery, the proximal carotid artery anastomosed to the left atrial appendage, and the pulmonary artery anastomosed to the proximal jugular vein, the heart is massaged until it is warmed and fibrillates. It is then defibrillated and allowed to carry on its normal function with a normal sinus rhythm.

In our studies thus far, 75 per cent of the hearts have fibrillated upon rewarming and have been capable of being defibrillated with normal sinus rhythm maintained. We feel that the practical application of this work lies in the fact that hearts may be capable of preservation over a 24 hour period by this technique for implantation as necessary.