Background and Purpose: Modified ultrafiltration after cardiopulmonary bypass (CPB) in children decreases body water, removes inflammatory mediators, improves hemodynamics, and decreases transfusion requirements. This prospective randomized study attempted to identify the best candidates for modified ultrafiltration during operations for congenital heart disease.

Methods: We randomized 100 consecutive patients with complex congenital heart disease undergoing operations with CPB between July 1996 and March 1997 into a control group (n=50) of conventional ultrafiltration and an experimental group using veno-venous modified ultrafiltration (n=50). Postoperative arterial oxygenation, duration of intubation, transfusion requirements, hematocrit, chest tube output, and time to chest tube removal were compared between the groups who were stratified by age and weight, CPB technique, existence of preoperative pulmonary hypertension, and defect.

Results: Modified ultrafiltration caused no complications. In patients with preoperative pulmonary hypertension, modified ultrafiltration significantly improved postoperative oxygenation

(PO2=360±140 vs control:293±100 mmHg, p=0.014); shortened ventilatory support (57±40 vs 189±127 hrs, p=0.003); decreased blood transfusion (15.6±15.2 vs 39.1±27.9 ml/kg, p=0.02); and led to earlier chest tube removal (p=0.03). In neonates (<30 days), modified ultrafiltration significantly reduced blood transfusion (17.1±17.2 vs 65.2±19.9 ml/kg, p=0.03) and duration of intubation (79.0±32.2 vs 259.5±145.6 hrs, p=0.013). In patients with prolonged CPB (>120 min), modified ultrafiltration significantly reduced the duration of intubation (56.5±40.7 vs 152.0±143.8 hrs, p=0.007). No significant differences were observed between modified ultrafiltration and control patients for any parameter in the presence of VSD without pulmonary hypertension, tetralogy of Fallot or aortic stenosis.

Conclusions: Modified ultrafiltration after CPB is safe and decreases the need for homologous blood transfusion, the duration of ventilatory support, and chest tube placement in selected patients with complex congenital heart disease. The optimal use of modified ultrafiltration includes patients with preoperative pulmonary hypertension, neonates, and patients who require prolonged CPB.