Pulmonary microvascular permeability after coronary arterial ligation in dogs

Recent studies have indicated that pulmonary microvascular permeability may be increased after coronary arterial ligation. We tested this by estimating the pulmonary microvascular reflection coefficient (delta) in six anesthetized control dogs and in six dogs in which we ligated the left anterior descending coronary artery. We cannulated lung lymph vessels and measured the lymph and plasma protein concentrations (CL and CP, respectively). The left atrial pressure was increased to decrease CL to a minimum. We used the minimum CL to estimate delta as 1 -CL/CP. delta for the control [0.70 +/- 0.03 (SD)] and coronary artery ligated groups (0.70 +/- 0.04) were almost identical. This data indicates that coronary artery ligation does not increase pulmonary microvascular permeability.