The changing pattern of inhaled nitric oxide use in the neonatal intensive care unit

The purpose of this study was to evaluate the demographic characteristics and outcomes of neonates who were admitted to a neonatal intensive care unit and treated with inhaled nitric oxide (iNO) during the years 2000-08. The goal of studying this group of neonates was to evaluate how iNO use has evolved in infants and to estimate the frequency of off-label use of this drug in this population.

Retrospective review of the Pediatrix Clinical Data Warehouse de-identified data set. Pediatrix Medical Group provides intensive care services in 244 hospitals in 32 states and Puerto Rico. Nine (3.7%) centers provide extracorporeal membrane oxygenation.

There were 494 255 neonates in the data set; 4316 (0.9%) were treated with iNO. The use of iNO increased from 154 of 32 967 patients in 2000 to 921 of 75 911 patients in 2008; a 2.6-fold increase (0.47 to 1.23%). There were 155 872 infants <34 weeks estimated gestational age discharged between 1 January 2000 and 31 December 2008; 1656 (1.1%) were treated with iNO. Since approval in 2000, the reported use of iNO in neonates <34 weeks increased from 0.3 to 1.8% in 2008; a sixfold increase in the reported use of iNO. The biggest increase occurred in infants between 23 and 26 weeks' gestational age (0.8 to 6.6%). In contrast, the increase in iNO use among neonates born ≥34 weeks has only increased from 0.5 to 1%.

The use of iNO has increased and the greatest increase has been the off-label use among preterm neonates.