Response to dopamine in prematurity: a biomarker for brain injury?

Abstract

ObjectiveIdentify factors associated with responsiveness to dopamine therapy for hypotension and the relationship to brain injury in a cohort of preterm infants.Study DesignThe pharmacy database at St. Louis Children’s Hospital was retrospectively queried to identify infants who (a) were born < 28 weeks gestation between 2012–14, (b) received dopamine, and (c) had blood pressure measurements from an umbilical arterial catheter. A control group was constructed from contemporaneous infants who did not receive dopamine. Mean arterial blood pressure (MABP) at baseline, 1h and 3h after initiating dopamine were obtained for each dopamine-exposed infant. MABP measurements at matched time points were obtained in the control group.ResultsSixty-nine dopamine-treated and forty-five control infants were included. Mean ΔMABP at 3h was 4.5±6.3 mm of Hg for treated infants versus 1±2.9 for the control. Median dopamine starting dose was 2.5 µg/kg/min. Dopamine-treated infants were less mature and lower birth weight while also more likely to be intubated at 72h, diagnosed with intraventricular hemorrhage (IVH), and to die. Failure to respond to dopamine was associated with greater likelihood of developing IVH (OR 5.8, 95% CI 1.1–42.3), while a strong response (ΔMABP >10 mmHg) was associated with a reduction in risk of IVH (OR 0.1, 95% CI 0.01–0.8).ConclusionsLow-moderate dose dopamine administration results in modest blood pressure improvements. A lack of response to dopamine is associated with a greater risk of IVH while a strong response is associated with a decreased risk. Further research into underlying mechanisms and management strategies is needed.