PULMONARY VASCULAR-RESISTANCE DURING LIPID INFUSION IN NEONATES

Using two-dimensional echocardiography, pulmonary vascular resistance was estimated from right ventricular pre-ejection period to ejection t ime (RVPEP/ET) in 11 preterm infants with respiratory distress, to tes t the effect of different doses of continuous lipid infusion. Echocard iography was performed at baseline with no lipid infusing 2 and 24 hou rs after 1.5 and 3 g/kg/day of intravenous lipid, 24 hours after disco ntinuing intravenous lipid emulsion, and 2 hours after restarting intr avenous lipid. After 24 hours of intravenous lipid at 1.5 g/kg/day the RVPEP/ET rose to mean (SD) 0.287 (0.03) from a baseline value of 0.22 5 (0.02) and to 0.326 (0.05) after 24 hours of intravenous lipid at 3 g/kg/day. Pulmonary arterial pressure returned to baseline 24 hours af ter the intravenous lipid had been discontinued. Continuous 24 hour in fusion of Lipid caused significant dose and time-dependent increases i n pulmonary vascular resistance. Intravenous lipid may aggravate pulmo nary hypertension.