Fluid Responsiveness Predictability in Immediate Postoperative Pediatric Cardiac Surgery. Is the Old Slandered Central Venous Pressure Back Again

OBJECTIVE Acute low cardiac output (CO) is a frequent scenario in pediatric cardiac intensive care units (PCICU). While fluid responsiveness has been studied extensively, literature is scarce for the immediate postoperative congenital heart surgery population admitted to PCICUs. This study analyzed the utility of hemodynamic, bedside ultrasound and Doppler parameters for prediction of fluid responsiveness in infants and neonates in the immediate postoperative cardiac surgery period. DESIGN A prospective observational study. SETTING University affiliated, tertiary care hospital, PCICU. PARTICIPANTS Immediate postoperative pediatric patients displaying a presumed hypovolemic low CO state were included. A clinical, arterial derived, hemodynamic, sonographic, Doppler-based, and echocardiographic parameter assessment was performed, followed by a fluid bolus therapy. INTERVENTIONS 15-20cc/kg Crystalloid fluid bolus. MAIN OUTCOME MEASURES Fluid responsiveness was defined as an increase in cardiac index > 10% by echocardiography. RESULTS Of 52 patients, 34 (65%) were fluid responsive. Arterial systolic pressure variation (SPV), continuous-Doppler preload parameters, and inferior vena-cava distensibility index (IVCDI) by bedside ultrasound all failed to predict fluid responsiveness. Dynamic central venous pressure (CVP) change yielded a significant but modest fluid responsiveness predictability of AUC 0.654 (p = 0.0375). CONCLUSIONS In a distinct population of mechanically ventilated, young, pediatric cardiac patients in the immediate postoperative period, SPV, USCOM preload parameters, as well as IVC-based parameters by bedside ultrasound failed to predict fluid responsiveness. Dynamic CVP change over several hours was the only parameter that yielded significant but modest fluid responsiveness predictability.