Prolonged suction drainage prevents serous wound discharge after cardiac surgery

A series of 180 patients was randomised to two groups after median sternotomy performed for cardiac surgery in order to evaluate the effect of suction drainage on serous wound discharge. In group A all wounds were drained using two conventional mediastinal drains, while in group B one suction drain and one conventional mediastinal drain were employed. Five patients developed serous wound discharge in group B compared with 14 in group A (chi 2, P < 0.02). There were no significant differences between the rates of major wound infection (group A, n = 1; group B, n = 1) or the incidence of postoperative pericardial effusion assessed by echocardiography (group A, n = 10; group B, n = 5).