Hypocalcemia and the patent ductus arteriosus

Abstract

THIS REPORT presents the findings of a controlled retrospective analysis undertaken to investigate the association of early neonatal hypocalcemia with persistent patency of the ductus arteriosus in low-birth-weight infants. METHODS The charts of all infants admitted to the Neonatal Intensive Care Unit of the Bronx Municipal Hospital Center (Kennedy Center Clinical Research Unit) between January 1, 1976, and April 30, 1978, with the diagnosis of PDA were reviewed. The diagnosis was based upon clinical evaluation by a senior neonatologist or a pediatric cardiologist, or both. The babies with PDA were subdivided into two groups: Subgroup A-infants managed successfully with fluid restriction, with or without administration of furosemide and digitalis, and Subgroup Bmore severely affected infants who, in addition to the above therapy, required indomethacin in an attempt to close their PDA. The criterion for the use of indomethacin was either the lack of improvement in concUrrent respiratory distress or the persistence of congest!ve heart failure after conservative medical managemen t . No infant in either group required surgical closure of the PDA. A control group of infants, without PDA, treated concurrently in the same unit, was matched by computer with the PDA group fo r gestationa! age, birth weight, and pattern of early respiratory distress. Both the control and the PDA groups were selected from the pool of neonates who survived the first two weeks of life, so that persistent patency of the ductus could be ascertained, and were either born in BMHC or transferred into the intensive care unit within the first 12 hours of life. All the infants were treated either in radiant warmers or incubators. Management of respiratory distress syndrome in both groups was similar. Those who required respiratory assistance were supported by a Bourns LS 104-150 volume ventilator (Bourns, IncorPorated, Life Systems, Riverside, Calif.). The babies were fed human milk when available, or PM 60/40 (24 calories/ounce) formula.