The possibility of prolonged survival of animals with an autotransplanted lung after removal of the intact contralateral lung

Abstract

We conducted a functional and morphologic examination of dogs that survived after pulmonary autotransplantation and removal of the contralateral lung. Left lung autotransplantation was performed in 260 dogs, and 3 animals were subjected to excision of the contralateral intact lung in the late postoperative period. In the late follow-up period, the respiratory function of the autograft became normal, but the compensatory reserves were somewhat reduced. The animals easily tolerated the exclusion of the intact lung from respiration for 10 minutes, with no signs of respiratory insufficiency. In the early period after removal of the intact lung, hyperventilation and gas exchange disorders developed in the autograft, resulting in arterial hypoxemia and metabolic acidosis. The changes disappeared by the fifteenth postoperative day. The general state of the animals improved, as well. In both the early and late postoperative periods (maximum follow-up 3¼ years), the autotransplanted left lung supported a normal level of ventilation and gas exchange. The efficiency of gas exchange was evidenced by the normal parameters of arterial and venous oxygen saturation and acid-base balance. Histologic examination demonstrated a compensatory hypertrophy in the autograft that was a reaction to the removal of the right (intact) lung. The autograft ensured normal vital functions of the body after the removal of the intact lung, demonstrating satisfactory indices of external respiration, blood gases, and acid-base balance. Its performance served as a convincing proof of the restoration of the function and structure of the organ.