Study on Closing Time after Indomethacin Administration in Prematurity with Patent Ductus Arteriosus

ABSTRACT

PURPOSE: In the clinical field, the closing time of patent ductus arteriosus(PDA) varies among patients after indomethacin administration. We tried to predict it by analyzing related factors, and also by understanding what affects it. METHODS: Among 30 cases of PDA at the NICU, 24 cases(male 14 cases, female 10 cases) were selected. Fifteen cases closed early(within 36 hours) and 9 cases closed late(after 36 hours) after indomethacin administration, cases of surgical ligation were excluded. PDA was confirmed by echocardiography which was done in an hour after murmur was heard, and then indomethacin was administered. Every 6 hours, 2D echocardiography was done and minimum internal diameter of ductus was measured. The magnitude and direction were gauged by flow mapping of the color Doppler. Ductal closure time is defined when there is no ductal flow. RESULTS: The median of the patent time was 28 hours in the early closed group and 50 hours in the late closed group. There were no significant factors statistically between the two groups in perinatal factors. The clinical status and several factors of study population at indomethacin administration were also not significant. Whereas, there were statistical differences in ductal size between the two groups(P<0.05). CONCLUSION: When indomethacin is intravenously administered to treat the PDA, ductal size differed between the two groups. This ductal size, measured by echocardiography before indomethacin administration is an important factor in predicting the closing time of PDA.