In healthy term infants and preterm infants without rds constriction and closure of the ductus arteriosus is complete within 4

Management of PDA in RDS

In healthy term infants and preterm infants without RDS constriction and closure of the ductus
arteriosus is complete within 48 hours of delivery in 90% of cases and in 100% by 96 hours.1,2
Closure is often delayed in preterm infants with RDS and is inversely related to gestational
age. In one study 42% of infants < 1000g developed a significant PDA and this decreased to
7% in infants with a birth weight between 1500 and 1750g.3 Echocardiography studies have
shown that in infants <1500g at birth requiring ventilation, a ductal diameter > 1.5mm in the
first 30 hours usually requires treatment.4 Antenatal steroids protect against symptomatic
PDA.5
The most widely used drug for closure of PDA is indomethacin. It has been used both
prophylactically and for the treatment of symptomatic PDA. Giving prophylactic
indomethacin within 24 hours of birth has definite short term benefits including a
significant decrease in the incidence of symptomatic PDA, the need for duct ligation
and in the incidence of Grade 3 and 4 IVH, but there is no difference in mortality or in
long term neurosensory impairment.6 Treatment also had no effect on on respiratory
outcomes or the incidence of necrotising enterocolitis.

Owing to adverse effects of indomethacin, including transient renal impairment and
decreased cerebral and gut blood flow, ibuprofen, which has a similar effect on ductal closure
but with potentially fewer side effects, has been used both prophylactically and for the
treatment of symptomatic PDAs. Ibuprofen reduces the incidence of PDA and has a similar
efficacy to indomethacin.7,8 It causes less reduction in blood flow to the brain, gut and kidneys
but there are concerns that it may increase respiratory morbidity. In one study 3 infants given
ibuprofen developed pulmonary hypertension9 and when compared to indomethacin more
infants receiving ibuprofen developed chronic lung disease.8 Consequently, ibuprofen does
not appear to confer any net benefits over indomethacin for the treatment of PDA and
indomethacin should remain the drug of choice. Several alternative dosage schedules are
used varying from 0.2mg/Kg 12 hourly for 3 doses to 0.1mg/Kg 24 hourly for 6 doses. The
prolonged course is associated with lower relapse rates and less biochemical disturbances10
and should be recommended although a loading dose of 0.2mg may be appropriate for
infants with symptomatic PDAs. Infants with renal impairment should not be given
indomethacin.
Reller MD, Zeigler ML, Rice MJ et al. Duration of ductal shunting in healthy preterm infants:
an echocardiographic colour flow Doppler study. J Pediatr 1988; 112:441-6.
Gentile R, Stevenson G, Dooley T et al. Pulsed Doppler echocardiographic determination of
time of ductal closure in normal newborn infants. J Pediatr 1981; 98:443-8.
Ellison RC, Peckham GJ, Lang P et al. Evaluation of the preterm infant for patent ductus
arteriosus. Pediatrics 1983;71:364-72.
Morales WJ, Angel JL, O’Brien WF et al. Use of ampicillin and corticosteriods in premature
rupture of membranes: a randomised controlled study. Obstet Gynecol 1989:73:721-6.
Kluckow M, Evans N. Early echocardiographic prediction of symptomatic patent ductus
arteriosus in preterm infants undergoing mechanical ventilation. J Pediatr 1995;127:774-9.
Fowlie PW, Davis PG. Prophylactic intravenous indomethacin for preventing morality and
morbidity in preterm infants (Cochrane review). The Cochrane library, issue 2, 2004.
Shah SS, Ohlsson A. Ibuprofen for the prevention of patent ductus arteriosus in preterm
and/or low birth weight infants (Cochrane Review). The Cochrane Library, Issue 2, 2004
Ohlsson A, Walia R, Shah S. Ibuprofen for the treatment of a patent ductus arteriosus in
preterm and/or low birth weight infants (Cochrane review). The Cochrane Library, issue 2,
2004.
Gournay V, Savagner C, Thiriez Get al Pulmonary hypertension after ibuprofen prophylaxis in very preterm infants. Lancet 2002;359:1486-7 Rennie JM, Cooke RW1. Prolonged low dose indomethacin therapy for the prevention of recurrences of patent ductus arteriosus of prematurity. Arch Dis child 1991;66:55-8.

Source: http://www.bapm.org/publications/documents/guidelines/RDS09_PDA.pdf