Abstract
Background
Studies in animal models have suggested that naloxone, a specific opiate antagonist, may improve outcomes for newborn infants with perinatal asphyxia.
Objectives
To assess the effects of naloxone versus placebo or no drug, and of single versus multiple doses of naloxone, on mortality, long term neurological problems, severity of hypoxic-ischaemic encephalopathy, and frequency of neonatal seizures in newborn infants greater than 34 weeks gestation with suspected perinatal asphyxia.
Search methods
The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2007), MEDLINE (1966 – February 2007), EMBASE (1980 – February 2007), conference proceedings, and previous reviews.
Selection criteria
Randomised or quasi-randomised controlled trials comparing naloxone versus placebo, or no drug, or another dose of naloxone, in newborn infants of greater than 34 weeks’ gestation with suspected perinatal asphyxia.
Data collection and analysis
Data was extracted using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of trial quality and data extraction by two authors. The pre-specified outcomes for this review were: death before hospital discharge, severe neurodevelopmental disability, severity of hypoxic-ischaemic encephalopathy, and seizures in the neonatal period.
Main results
Only one eligible randomised controlled trial was identified. This study compared the use of naloxone with placebo in newborn infants with an Apgar score of six or less at one minute after birth. There were not any data on the pre-specified outcomes for this review.
Authors’ conclusions
There are insufficient data available to evaluate the safety and effectiveness of the routine use of naloxone for newborn infants of greater than 34 weeks’ gestation with suspected perinatal asphyxia. A further randomised controlled trial is needed to determine if naloxone benefits newborn infants with suspected perinatal asphyxia. Such a trial should assess clinically important outcomes such as mortality, and adverse short and long term neurological outcomes.
Plain language summary
Naloxone for preventing morbidity and mortality in newborn infants of greater than 34 weeks’ gestation with suspected perinatal asphyxia
Newborn infants who have been deprived of oxygen before, during, or after delivery (“perinatal asphyxia”) are at high risk of dying or developing brain damage. Studies in animal models suggest that over-production of the bodies’ own opioids (substances similar to drugs like morphine) is detrimental. Furthermore, researchers have found that giving newborn animals with perinatal asphyxia a drug to counteract the effects of opioids (naloxone, an opioid antagonist) is beneficial. We found only one small randomised controlled trial that examined whether giving naloxone to newborn infants with suspected perinatal asphyxia improved their outcomes, but this trial did not assess the effect on death or disability. Further trials large enough to determine whether naloxone improves survival and/or reduces disability rates are therefore needed.
