Ventilation of Newborn Lambs by Means of a Donor Lung. ∗

Abstract

Isolated lungs of dogs and cats have been shown to retain their diffusion capacity for many hours(1,2), and excised dog lungs have also displayed a fair ability to function as human kidney(3). In view of the durability and adaptability of pulmonary tissue, an investigation was performed in which donor lungs were attached to the circulation of live animals, and the effects of this shunt upon blood oxygenation and upon survival of the recipient animals were studied.

Although time and circumstances did not permit additional experiments for resolution of the problems involved in this procedure, this report is presented in the belief that the findings may be of use to other investigators working in this field.

Experimental procedures. Mongrel laboratory dogs were used to supply the donor lungs. The animals were anesthetized (pento-barbital 30 mg/kg i.v.), heparinized (10 mg/100 ml blood), and exsanguinated; the chest was opened through a midsternum incision. The thoracic aorta was ligated in several places in order to block fluid outflow from the bronchial arteries; ligatures were also placed on the superior and inferior venae cavae, and on the azygos vein. The pulmonary artery was cannulated via the right ventricle, and a second cannula was placed in the left atrium. Polyethylene tubes were attached to the cannulae, the chest walls were sewn together with tubes emerging, and 4 to 6 liters of a 6% dextran-saline perfusion solution were pumped at low flow rate and pressure (less than 20 mm Hg) via the tubes through the lungs for several hours in order to wash out the residual blood and other antigenic substances. Then the pulmonary blood vessels were left filled with the heparin-ized perfusion fluid at a pressure intermediate between umbilical arterial (70 mm Hg) and umbilical venous (10 mm Hg)(4).