According to a new study, prolonged episodes of hypoxemia among extremely preterm infants during the first 2 to 3 months after birth were associated with an elevated risk of disability or death at 18 months.

Christian F. Poets, MD, of Tuebingen University Hospital in Germany, and colleagues aimed to examine the connection between intermittent hypoxemia or bradycardia and death or disability. The study included 1,019 infants with gestational ages of 23 weeks 0 days through 27 weeks 6 days who were born between December 2006 and August 2010 and survived to a postmenstrual age of 36 weeks, according to a Medical Xpress report.

The researchers conducted follow-up assessments that occurred between October 2008 and August 2012. The team used data from infants who were part of the Canadian Oxygen Trial. The average percentages of recorded time with hypoxemia for the least and most affected 10% of infants were 0.4% and 13.5%, respectively, and corresponding values for bradycardia were 0.1% and 0.3%. The Medical Xpress news report indicates the primary outcome (a composite of death after 36 weeks’ post menstrual age, severe hearing loss, blindness at 18 months, motor impairment, cognitive or language delay) was ascertained for 972 infants and present in 414.

Hypoxemic episodes were linked with an estimated increased risk of late death or disability at 18 months of 56.5% in the highest decile of hypoxemic exposure vs 37% in the lowest decile. The Medical Xpress report notes the association was significant only for prolonged hypoxemic episodes lasting at least 1 minute. Relative risks for all secondary outcomes were similarly increased after prolonged hypoxemia.

The researchers write, “If these observations are confirmed in future studies, further research on the prevention of such episodes will be needed.” The authors add that should the observation be confirmed in future research that episodes of hypoxemia lasting less than 1 minute are not associated with adverse outcomes in extremely preterm infants, this would be important information for both clinicians and parents.

In an accompanying editorial, Lex W. Doyle, MD, writes, “If hypoxemia is proven to cause adverse neurodevelopment, any future interventions to reduce prolonged hypoxemic episodes, such as doxapram [a respiratory stimulant] or higher doses of caffeine, as suggested by Poets et al, must be evaluated in rigorous randomized clinical trials to minimize exposure to therapies that are useless or even harmful.”

Source: Medical Xpress