PRESSURE-GRADIENT ACROSS THE PULMONARY-ARTERY ANASTOMOSIS DURING LUNGTRANSPLANTATION

Background. Perioperative monitoring of pulmonary artery (PA) pressure s in lung transplant recipients is critical. This report characterizes an intraoperative gradient across the PA anastomosis in a series of p atients undergoing bilateral sequential lung transplantation. Methods. Hemodynamic measurements were obtained in a series of 10 patients bef ore anesthetic induction, during one-lung ventilation/perfusion of the newly transplanted first lung with the PA catheter proximal and dista l to the anastomosis and after arrival in the intensive care unit The following measurements were recorded: central venous pressure, cardiac output, PA occlusion pressure, and systemic and pulmonary arterial pr essures (systolic, diastolic, mean). Results. Although a systolic pres sure gradient of more than 10 mm Hg across the anastomosis was observe d in all patients, there was a significant variation in systolic (13 t o 59 mm Hg), diastolic (2 to 10 mm Hg), and mean (5 to 27 mm Hg) FA gr adients. Mean proximal systolic PA pressure measurements (56.2 +/- 20. 6 mm Hg) were greater when compared to measurements obtained distal to the anastomosis (28.6 +/- 10.1 mm Hg, p = 0.001) and to those obtaine d in the postoperative period (32.1 +/- 9.7 mm Hg, p = 0.004). Conclus ions. The present study demonstrates that during single-lung ventilati on and perfusion, the PA pressure measured proximally may not reflect accurately the pressure distal to the vascular anastomosis.