[Pulmonary flow-resistance relation in allografts ten days after single lung transplantation in dogs]

In order to evaluate the applicability of single lung transplantation as a treatment of pulmonary hypertension, I investigated the relationships between the pulmonary flow and its resistance in allografts ten days after single lung transplantation in dogs. Fourteen dogs underwent single lung transplantation. All dogs received azathioprine (50 mg; given orally) and methylprednisolone sodium succinate (125 mg; given intravenously) every day after operation. Eight dogs survived up to ten days after operation. In the survived recipients and the five healthy dogs, pulmonary flow-resistance relations were investigated. Pulmonary flow was exactly regulated by the pump system, which drained from both cavae and returned to right atrium via azygos vein. The pulmonary artery of native lung or right lung was clamped prior to the measurement. Pulmonary vascular resistance was recorded with the increase of pulmonary flow at the range from 0.3 L/min. to 2.0 L/min. by 0.1 L/min. Lung water was measured by means of Wood's method. Radiographical and pathological examinations were appended. The five allografts received complete studies (successful group) were twice lung water of the healthy lungs (control group) (successful group; 95.6 +/- 16.7 g, control group; 47.8 +/- 7.5 g), and chest roentgenograms of successful group showed mild or moderate consolidation. The other allo-grafts (unsuccessful group), including ones died before investigations, were four times lung water of control group (unsuccessful group; 211.0 +/- 89.6 g), and the chest roentgenograms showed severe consolidation. But any difference was not found in any pulmonary flow between the pulmonary resistance in successful group and in control group. These results show that the allografts, which is under about twice lung water of normal lung, maintains enough pulmonary vascular function, and I concluded that single lung transplantation can be an effective treatment for pulmonary hypertension.