Temporarily pulmonary hilum clamping as a thoracic damage-control procedure for lung trauma in swine

Temporarily pulmonary hilum clamping is available for the trauma surgeon to deal with serious pulmonary injuries, but the physiologic influence needs further evaluation. This study was to establish a temporary pulmonary hilum clamping model for thoracic damage-control surgery and determine the safety time latitude of this manipulation.

After anesthetized and catheter instrumented, the left pulmonary hilus of pigs were clamped with a urethral catheter after thoracotomy maintained for three different time period, 90 minutes (C90), 120 minutes (C120), and 150 minutes (C150), and then unclamped. Hemodynamic data were recorded and serum samples were collected for d-dimer detection and other hematology analysis, as well as 1 cm3 pulmonary tissue was obtained for histologic study before clamping, at the end of clamping, and at 0.5, 1, 1.5, 2, and 4 hours after unclamping.

There were 100% of C90, 83.3% of C120, and 33.3% of C150 pigs survived. Animals of C150 group suffered highest blood pressure and heart rate, respiratory index, pulmonary dynamic compliance, and cardiac output. Pulmonary vascular resistance, platelet count, and D-dimer showed minor significant changes between C90 and C120 groups, whereas a marked changes in C150 animals during the study. There were much more serious histologic changes in C150 group compared with C90 and C120 groups.

We established a pulmonary hilum clamping animal model for pulmonary damage investigation. It was determined that 120 minutes was the longest safety time for hilum clamping without lethal pulmonary injury in porcine.