This study was designed to examine whether concomitant administration of anti-free radicals with donorcore cooling on cardiopulmonary bypass (CPB) and hypothermic storage of the heart and lung, could provide successful extended cardiopulmonary preservation. Fourteen sheep heart-lung blocks harvested after core-cooling and cardioplegic arrest were preserved at 4 degrees C for 8.5 hr. Before and during CPB, the animals were perfused with Prostaglandin E1 (PGE1), superoxide dismutase (SOD), catalase (CAT) and deferoxamine (DEF). Cardioplegic arrest was induced with St. Thomas' Hospital solution (Plegisol) to which SOD, CAT and DEF had been added. The preservation solution consisted of Plegisol modified by the addition of K-lactobionate, raffinose, mannitol, SOD, CAT, DEF, a phosphate buffer and penicillin. Histological examination performed on 3 donor heart-lung blocks before and after CPB and cardioplegia, then immediately following cold storage, produced no clear evidence of structural damage in cardiac myocytes and lung parenchyma. Eleven donor organs were therefore transplanted in size-matched recipients with a total mean ischemic time of 12 hr. The combined administration of SOD, CAT, DEF, insulin and glucose during the initial period of reperfusion had no beneficial effect on cardiopulmonary performance. A progressive fall in Pa O2 and mean aortic pressure was observed post-operatively in the 7 animals that were weaned from CPB. Five of them died within 3 to 5 hr after CPB weaning, the remaining 2 animals died of cardiac arrest within the fourth hour. The results of this experiment seem to indicate that: 1. better organ function and improved survival could have been obtained if the duration of anti-radical treatment had been prolonged after reperfusion and, 2. physical manipulation of the donor grafts during harvesting and transplantation may have been partly responsible for the poor post-transplantation cardiopulmonary performance.
Between November 1989 and February 1990, 66 randomized sternotomized patients underwent aortocoronary bypass and were subjected to a sternal scanner in the early postoperative period. Each examination included a manubrial and a sternal body print. At each level, we studied the occurrence of spacing or misalignment of the sternal layers. The 66 patients were subdivided into four groups according to the type of conduit harvested (single left internal thoracic artery or saphenous vein) and the type of material used for the sternal closure (steel wires or nylon yarns). In all cases, adequate early sternal approximation, which is represented by a good alignment as well as by an excellent contact of the sternal layers, was infrequently demonstrated. Moreover, the two abnormalities most often observed were manubrial spacing and sternal body misalignment. The sternal closure technique and internal thoracic artery harvesting had no significant effect on the sternal approximation. To minimize manubrial spacing and sternal body misalignment, we propose that the surgeon should apply three threads through the manubrium, withdraw the shoulder roll beforehand, elevate both of the patient's shoulders, and maintain the two xyphoid layers in the same plane and in fairly close contact during the tightening of the wires.
We describe a new technique for the placing and fixing of extracorporeal circulation cannulae in the heart. Two devices are involved, the first for an atrial or venous return cannula and the second for an aortic perfusion cannula. These allow quick easy cannulation which is very important in emergency surgery.