Increasing mean arterial blood pressure and heart rate with catecholaminergic drugs does not improve the microcirculation in children with congenital diaphragmatic hernia: a prospective cohort study.

OBJECTIVE: To study whether dopamine, norepinephrine, and epinephrine improve not only mean arterial blood pressure and heart rate but also microcirculatory perfusion in children with congenital diaphragmatic hernia.
DESIGN: Prospective observational cohort study from November 2009 to July 2012.
SETTING: ICU of a level III university children's hospital. PATIENTS: Twenty-eight consecutive congenital diaphragmatic hernia newborns of whom seven did not receive any catecholaminergic support and 21 received dopamine as the drug of first choice. Fourteen of the latter also received either norepinephrine or epinephrine in addition to dopamine. Twenty-eight healthy neonates, matched for gestational age, postnatal age, and gender, served as controls.
INTERVENTIONS: None.
MEASUREMENTS AND MAIN RESULTS: Data were obtained before and after dopamine start and before and after norepinephrine or epinephrine start in case it was given. For the congenital diaphragmatic hernia without catecholaminergic support, data were obtained at admission days 1 and 2 and for the controls on day 1 of life. The buccal microcirculation was studied using Sidestream Dark Field imaging. Also macrocirculatory, respiratory, and biochemical variables were collected. Mean arterial blood pressure had improved after dopamine start, whereas the microcirculation had not. After the start of either norepinephrine or epinephrine, both blood pressure and heart rate had increased. However, the microcirculation failed to improve again. The microcirculation in the healthy controls was better than that in the congenital diaphragmatic hernia patients with catecholaminergic support. After cutoff values for abnormal microcirculation had been defined, abnormal microcirculation after dopamine start predicted the need for additional catecholaminergic support (area under the curve, 0.74-0.88; sensitivity, 77-77%; specificity, 69-77%). Likewise, microcirculatory impairment was associated with the need for extracorporeal membrane oxygenation.
CONCLUSIONS: Catecholaminergic drug support with dopamine, norepinephrine, and/or epinephrine improved macrocirculatory function but did not improve the microcirculation in neonates with congenital diaphragmatic hernia. The microcirculation was not only impaired but it also predicted poor outcome.