A new approach to the treatment of pleural effusions after coronary artery bypass grafting

Postoperative pleural effusion is the most common complication of cardiac surgery. The aim of our work was to evaluate the effects of NSAIDs alone, NSAIDs combined with steroids, and NSAIDs combined with metalloproteinase (MMP) inhibitor on the severity of inflammation in the pleural cavity in patients undergoing coronary artery bypass grafting. The study included 22 patients with coronary artery disease who underwent coronary artery bypass grafting with cardiopulmonary bypass. To determine the activity of MMP-9, venous blood was sampled on days 1, 5, and 10 after the beginning of anti-inflammatory therapy. Patients were randomly assigned into 3 groups: group I consisted of patients who were prescribed monotherapy with NSAIDs (75 mg/day diclofenac; n=8), group II consisted of patients who were prescribed with a combination of anti-inflammatory therapy with NSAIDs + steroids (75 mg/day diclofenac + 0.5 mg/kg/day prednisolone; n=8) and group III included patients who used the combination therapy minocycline + NSAIDs (75 mg/day diclofenac + 100 mg/day minocycline). The main criterion for evaluating the effectiveness of anti-inflammatory treatment was reduction in the activity of pro-MMP-9 in venous blood samples. The additional criteria were formation of effusions in pleural and pericardial cavities and duration of persistence of pleural effusion according to ultrasound examination. The main criterion for the effectiveness of prevention of postpericardiotomy syndrome was the absence of its clinical signs within 30 days after surgery. Combination treatment with NSAIDs with MMP inhibitor exerted the greatest therapeutic effects on pleural effusions after coronary artery bypass grafting. The therapeutic effects began starting from day 5 of therapy. Moreover, transthoracic echocardiography demonstrated significant decrease in the time of detection of the effusions in the pleural cavities.