Modified Ultrafiltration Improves Lung Mechanics in Congenital Cardiac Surgery - A Fact or Futile: A Prospective, Observational, Single-Center Study

Abstract

Objective: Cardiac surgeries involving cardiopulmonary bypass (CPB) can have adverse effects on patients, potentially increasing morbidity. In infants who possess lower blood volume and are exposed to the more artificial surface and larger prime volumes of the CPB, the harmful effects can be significant. Several studies have indicated that modified ultrafiltration (MUF) may yield beneficial effects in cardiac surgery by reducing inflammatory markers, improving hemodynamics, and decreasing excess body water. Our study seeks to evaluate the impact of MUF on pulmonary mechanics in infants undergoing cardiac surgeries on CPB. Methods: This prospective, observational, single-center study was conducted on 56 infants with congenital heart disease, who underwent cardiac surgery, followed by CPB, were included in this study. The primary outcomes were oxygen saturation (SPO2), hemoglobin (Hb), peak inspiratory pressure (Ppeak), and plateau pressure (Pplat). The secondary outcomes were systolic and diastolic invasive blood pressures (IBPs), mean arterial pressure (MAP), mean airway pressure (Pmean), static lung compliance (C-stat), dynamic lung compliance (C-dyn), expiratory resistance (Re), and work of breathing (WOB). Results: A statistically significant increase in SPO2 (98.7 vs. 99.1), Hb (8.3 vs. 13.3), IBPsystolic (85 vs. 90), IBPdiastolic (56 vs. 61.4), and MAP (66.4 vs. 73.2) was observed in congenital cardiac surgery and CPB patients after MUF (all p<0.05). A statistically significant post-procedural decline in Ppeak (18.8 vs. 18.3), Pplat (18.4 vs. 18.1), Re (79.8 vs. 78), and WOB (1.4 vs. 1.3) was also observed (all p<0.05). However, no significant pre-procedural versus post-procedural differences were observed in Pmean, C-stat, and C-dyn (all p>0.05). Conclusion: MUF effectively improved lung mechanics, oxygen saturation, myocardial contractility, hematocrit, and hemodynamics, and minimized the blood transfusion requirement after CPB in infants with congenital heart disease. Future studies should reinvestigate these outcomes with a larger sample size for an extended follow-up duration.