Dopamine treatment in neonatal medicine with a focus on non-responder
Background: Haemodynamic adaptation in the first few days of life is a complex physiological process that often is disturbed in premature or sick infants. Systemic hypotension occurs in 20–50% of all infants admitted for neonatal intensive care and can have serious consequences including IVH, PVL and NEC. First line therapy involves expansion of the circulatory blood volume. If that is not sufficient, the neonate usually will be treated with inotropes. Dopamine is the most frequently used sympathomimetic amine for the treatment of hypotension in neonates. The common dosage for dopamine ranges from 3–20mg/kg/min. However, a significant proportion of neonates do not respond sufficiently to treatment with Dopamine. Aim of the study: We analyse the characteristics of dopamine-non-responders aiming to identify possible predictors of non-responsiveness to inotropes.
Materials and methods: We analysed 95 premature and term babies born between 1/1/2008 and 31/12/2009 treated at the Trevor Mann Baby Unit, Brighton, UK who were treated with inotropes and/or steroids for systemic hypotension. Results: 87 (91.6%) of our 95 patients received Dopamine as first line treatment. Out of these 33 infants (37.9%) received Dopamine only (classified as „Responder“, R). The remaining 54 infants (62.1%) required additional treatment with Dobutamine, Adrenaline and/or Hydrocortisone (classified as „Non-Responder“, NR). Mean gestational age in the R group was 28+4 weeks, with 6 babies (18%) being term, mean birth weight was 1304g (±1048g) and mean duration of Dopamine-treatment was 2.9 days. In the NR group, mean gestational age was 31+5 days with 18 babies (33%) being term, mean birth weight was 1838g (±1373g), and mean duration of Dopamine-treatment was 5.2 days. Additional hypotensive treatment in the NR group consisted of Adrenaline in 22 (40.7%), Dobutamine in 41 (75.9%) and Hydrocortisone in 23 (42,6%) babies.
Conclusion: Dopamine is the most commonly used inotropic drug for treatment of systemic hypotension in neonates. However, only 1/3 of patients can be treated sufficiently with dopamine alone, nearly 2/3 of all patients require additional treatment with other inotropes or steroids. This is more likely in term babies of whom 75% required additional treatment than in preterm babies of whom 42.9% responded to Dopamine alone.