Dopamine plasma clearance is increased in piglets compared to neonates during continuous dopamine infusion

Cerebral Autoregulation in Sick Infants: Current Insights

Cerebrovascular autoregulation is the ability to maintain stable cerebral blood flow within a range of cerebral perfusion pressures. When cerebral perfusion pressure is outside the limits of effective autoregulation, the brain is subjected to hypoperfusion or hyperperfusion, which may cause vascular injury, hemorrhage, and/or hypoxic white matter injury. Infants born preterm, after fetal growth restriction, with congenital heart disease, or with hypoxic-ischemic encephalopathy are susceptible to a failure of cerebral autoregulation. Bedside assessment of cerebrovascular autoregulation would offer the opportunity to prevent brain injury. Clinicians need to know which patient populations and circumstances are associated with impaired/absent cerebral autoregulation.

Association between dopamine and cerebral autoregulation in preterm neonates

BACKGROUND

To test the hypothesis that dopamine is associated with impaired cerebral autoregulation (ICA) in a dose-dependent fashion.

METHODS

Non a priori designed secondary analysis of a prospectively enrolled cohort study subjects <12 h of life between 24⁰ and 29⁶ weeks gestation. Cerebral saturations (rScO2) and mean arterial blood pressure (MAP) were continuously monitored every 30 s for 96 h. ICA was defined by a 10 min epoch rScO2-MAP correlation coefficient of >0.5.

RESULTS

Twenty-three of 61 subjects (38%) required dopamine. Time spent with ICA was 23% in dopamine-exposed subjects vs. 14% in those not exposed (p = 0.0001). On the epoch level, time spent with ICA was 15%, 29%, 34%, 37%, and 23% in epochs with dopamine titration of 0, 1-5, 6-10, 11-15, and 16-20 μg/kg/min, respectively. Using mixed-effect modeling, ICA for each dopamine titration was significantly higher than unexposed times when controlling for gestation, presence of a patent ductus arteriosus, day of life, MAP less than gestational age, and illness severity score (p < 0.02).

CONCLUSIONS

Dopamine exposure during the first 96 h was associated with ICA. Time periods with ICA increased with dopamine exposure in a dose-dependent fashion peaking at a concentration of 11-15 μg/kg/min.