Pulmonary mechanics after cardio-pulmonary transplantation, an experimental study

An experimental model was developed in pigs (weight: 25 +/- 2 kg), to evaluate pulmonary mechanics during the first 2 h of reperfusion following heart-lung transplantation. We studied two groups with three transplantations each: group A (45 min of preservation) and group B (6 h of preservation). After rinsing out the heart-lung mass by the injection of a cold intracellular solution (K+ = 115 mEq/l) into the aorta and the pulmonary artery, the organs were removed and conserved in a cold environment (0.5 degrees C). The orthotopic heart-lung transplantation was carried out using extra-corporeal circulation. Pulmonary mechanics were evaluated before and after transplantation by measuring the pulmonary compliance (C), and the aero-dynamic resistance (R) with an interrupted air flow technique. [table: see text] The duration of ischaemia appeared to be a pernicious factor in cardiopulmonary function. In all cases, the protection protocol of the heart-lung block had allowed a cutting-off of the cardiorespiratory assistance. However, there were major pulmonary mechanical perturbations, associated with a reduction in the pulmonary compliance and a very important increase in the aerodynamic resistance.