Hemodynamic effects of sodium bicarbonate in critically ill neonates

Abstract

To analyze the cardiovascular effects of sodium bicarbonate in neonates with metabolic acidosis. Prospective, open, non-randomized, before-after intervention study with hemodynamic measurements performed before and 1, 5, 10, 20, and 30 min after bicarbonate administration. Neonatal intensive care unit, tertiary care center. Sequential sample of 16 paralysed and mechanically ventilated newborn infants with a metabolic acidosis (pH2) (+11.8%), and transcutaneous oxygen pressure (PtcO₂) (+8%). In spite of the PaCO₂ elevation, pH significantly improved (from a mean of 7.24 to 7.30), and the base deficit decreased (−39.3%). Calculated systemic vascular resistance (SVR) (−10.7%) and diastolic BP (−11.7%) decreased significantly, while PaO₂ and heart rate (HR) did not change. Central venous pressure (CVP) (+6.5%) increased only slightly. By 30 min after bicarbonate administration all hemodynamic parameters, with the exception of the diastolic BP, had returned to baseline. Sodium bicarbonate in neonates with metabolic acidosis induces an increase in contractility and a reduction in afterload.