The effect of modified ultrafiltration duration on pulmonary functions and hemodynamics in newborns and infants following arterial switch operation*.

OBJECTIVES: Modified ultrafiltration is used to ameliorate the deleterious effects of cardiopulmonary bypass in pediatric cardiac surgery patients. The ideal duration of modified ultrafiltration has not been established yet. We investigated the effects of extended duration of modified ultrafiltration on pulmonary functions and hemodynamics in the early postoperative period in newborns and infants who had transposition of great arteries operations. DESIGN: Single-center prospective randomized study. SETTING: Pediatric cardiac surgery operating room and ICU. PATIENTS: Sixty newborns and infants who had been scheduled to undergo transposition of great arteries operation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Modified ultrafiltration was applied to all patients following the termination of cardiopulmonary bypass (for 10, 15, and 20 min in groups 1, 2, and 3, respectively). Pulmonary compliance, gas exchange capacity, hemodynamic measurements, inotropic support, blood loss, transfusion requirements, hematocrit level, and duration of ventilatory support were measured after intubation, at termination of cardiopulmonary bypass, at the end of modified ultrafiltration, and in the 1st, 6th, 12th, and 24th hours after admission to ICU. The amount of fluid removed by modified ultrafiltration in groups 2 and 3 was larger than that of group 1 (p < 0.01). Systolic blood pressure was significantly increased at the end of modified ultrafiltration in group 3 compared to groups 1 and 2 (p < 0.05). Hematocrit levels were significantly increased at the end of modified ultrafiltration in groups 2 and 3 compared to group 1 (p < 0.01). Therefore, RBCs were transfused less after modified ultrafiltration in groups 2 and 3 compared to group 1 (p < 0.05). Static and dynamic compliance, oxygen index, and ventilation index had improved similarly in all three groups at the end of modified ultrafiltration (p > 0.05) CONCLUSIONS:: Modified ultrafiltration acutely improved pulmonary compliance and gas exchange in all groups. Increased hematocrit and blood pressure levels were also observed in the longer modified ultrafiltration group. However, extended duration of modified ultrafiltration did not have a significant impact on duration of intubation or the stay in ICU.