부산대학교 도서관

OBJECTIVE: To assess ductus arteriosus (DA) blood flow directly after birth in healthy term infants after elective caesarean section. DESIGN: In healthy term newborns, echocardiography was performed at 2, 5 and 10 min after birth to monitor cardiac output and DA blood flow. Heart rate (HR) was assessed using ECG. SETTING: The delivery rooms of the Leiden University Medical Center. PATIENTS: 24 healthy term infants born after a caesarean section were included in this study. RESULTS: Mean (SD) HR did not change (158 (18) beats per minute (bpm), 5 min (159 (23) bpm) and 10 min (156 (19) bpm). DA diameter decreased from 5.2 (1.3) mm at 2 min to 4.6 (1.3) mm at 5 min (p=0.01) to (3.9 (1.2) mm) (p=0.01) at 10 min. Right-to-left DA shunting was unaltered (median (IQR) 95 (64–154) mL/kg/min to 90 (56–168) mL/kg/min and 80 (64–120) mL/kg/min, respectively (ns)), whereas left-to-right shunting significantly increased between 2 and 5 min (41 (31–70) mL/kg/min vs 67 (37–102) mL/kg/min (p=0.01)) and increased significantly between 2 and 10 min (93 (67–125)) mL/kg/min (p<0.001). Right-to-left/left-to-right shunting ratio decreased significantly from 2.1 (1.4–3.1) at 2 min to 1.4 (1.0–1.8) at 5 min (p<0.0001) and to 0.9 (0.6–1.1) at 10 min (p<0.0001). CONCLUSIONS: DA shunting changes swiftly from predominantly right-to-left shunting to predominantly left-to-right shunting at 10 min after birth, reflecting differential changes in pulmonary and systemic vascular resistance.