Objective: Assess the effect of increasing pulse oximetry targets on incidence of pulmonary hypertension in very low birthweight premature infants.
Study design: Retrospective cohort study comparing pulmonary hypertension incidence among three cohorts of premature infants exposed to varying oxygen saturation targets (Cohort 1: n=459, 1 May 2009 to 30 April 2011, 85-94%; Cohort 2: n=474, 1 May 2011 to 31 May 2013, 88-94%; Cohort 3: n=387, 1 June 2013 to 31 May 2015, 90-95%). Subjects had birth weight <1500 g and gestational age 23-32 weeks. Chi-square, Kruskall-Wallis and Anderson-Darling tests were used, as well as multivariable logistic regression.
Results: Incidence of pulmonary hypertension declined with higher oxygen saturation targets (19.0% Cohort 1, 7.9% Cohort 2, 9.6% Cohort 3, P<0.001). Other parameters were largely not different between cohorts though rates of chorioamnionitis and prenatal steroids increased and oxygen use, inhaled nitric oxide use, necrotizing enterocolitis and patent ductus arteriosus ligation decreased over time.
Conclusion: Higher oxygen saturation targets for very low-birthweight premature infants were associated with reduced rates of pulmonary hypertension in this retrospective cohort study.