Postoperative pericardial effusion and its relation to postpericardiotomy syndrome.

Postpericardiotomy syndrome often delays recovery from cardiac operation. Pericardial effusion is an important sequela of postpericardiotomy syndrome. To define the relationship between postpericardiotomy syndrome and pericardial effusion, we performed four to seven serial echocardiograms (echoes) between postoperative day 0 and postoperative day 10 in 40 children who had operation requiring pericardiotomy. We also performed daily physical examination on each patient for clinical evidence of postpericardiotomy syndrome. Echocardiographic signs of pericardial effusion developed in 21/40 patients (53%). The effusion was present by postoperative day 5 in 19/21 patients. Clinical signs of postpericardiotomy syndrome occurred in 18/40 patients (45%). Among the 18 patients with postpericardiotomy syndrome, 16 had echocardiographic evidence of pericardial effusion. Thus the sensitivity of the echocardiogram was 89%. The pericardial effusion always developed prior to and persisted through clinical symptoms. We conclude that (1) pericardial effusion is present in over 50% of the patients following cardiac surgery, (2) it develops early in the postoperative period, and (3) once present, the effusion is persistent and frequently followed by clinical evidence of postpericardiotomy syndrome.