- medical management of patent ductus arteriosus
- a nonsteroidal anti-inflammatory drug (NSAID), indomethacin is an inhibitor of prostaglandin synthesis; it acts on the cyclo-oxygenase pathway
- the inhibition of prostaglandin E1 synthesis results in constriction of smooth muscle around the ductus
- absorption of oral indomethacin in neonates is poor (approx. 20%)
- highly protein bound, but apparently no displacement of bilirubin from albumin occurs at normal serum concentrations
- in premature neonates the clearance of indomethacin increases with increasing postnatal age
- in a small number of neonates the mean half life has been reported to be 20-28 hours during the first week of life, and 12-19 hours after the first week
- indomethacin is more effective early in the infant's course
- renal dysfunction, as manifested by oliguria, increase in BUN and serum creatinine, and a fall in Glomerular Filtration Rate (GFR); these appear to be reversible
- GI: bleeding, gastric ulceration, possible reduction in blood flow, association with development of NEC
- abnormal platelet aggregation
- hyponatremia (due to suppression of urine volume), hyperkalemia, hypoglycemia
- infants with proven or suspected infection that is untreated
- infants who are bleeding
- thrombocytopenia, coagulation defects, proven or suspected NEC, significant impairment of renal function, known hepatic disease, significant hyperbilirubinemia (>170 umol/L), congenital heart disease
- evolving intraventricular hemorrhage
- before administration of the drug the following studies must be done: bilirubin, electrolytes, BUN, creatinine, urinalysis, urine specific gravity, WBC, Hgb, Hct, platelets
- continue to monitor urine specific gravity, serum Na, infant's weight, and accurate intake and output
- decrease fluid intake before this medication is given
- vial containing 1 mg of sterile, lyophilized powder
- add 2 mL of sterile water for injection to prepare a 0.5 mg/ mL solution
- 0.2 mg/kg IV q24h
- a course of therapy is from 1 to 3 doses
- a 2nd course of 1 to 3 doses may be given
- administer by IV infusion OVER AT LEAST 20 MINUTES (cerebral blood flow appears to be decreased when indomethacin is given quickly; this does not appear to occur when it is administered over at least 20 minutes)
- may be given by an RN; a physician does not have to be present in the unit
- McEvoy G K (ed): AHFS Drug Information, American Society of Hospital Pharmacists, 1991.
- Roberts, RJ: Drug Therapy in Infants, W.B. Saunders, Toronto, 1984.
- Colditz P, Murphy D, Rolfe P and Wilkinson AR: Effect of infusion rate of indomethacin on cerebrovascular responses in preterm neonates, Arch Dis Child 1989; 64:8-12.
- Krogh CME et al (ed): Compendium of Pharmaceuticals and Specialties, Canadian Pharmaceutical Association, 1992.
- Gomella TL (Ed): Neonatology - Management, Procedures, On-Call Problems, Diseases, Drugs, 1992, Appleton and Lange, Norwalk, Connecticut.
- Bhatt DR, Furman GI, Reber DJ et al: Neonatal Drug Formulary, 1990-1991, 2nd Edition, Fontana, California 92334.