Abstract
OBJECTIVE: To identify medications associated with changes in serum potassium concentrations in critically ill neonates. METHODS: A prospective cohort study was conducted between March 2023 and March 2024 in the neonatal intensive care units of a public maternity hospital in Brazil. Neonates admitted for over 24 hours and receiving at least one medication were included. Serum potassium levels were monitored daily, and associations with medications were assessed using mixed-effects linear regression models. Medications used to correct potassium levels were excluded from the analysis. RESULTS: Among 336 neonates included, the mean gestational age was 33.8 ± 4.0 weeks, and the mean serum potassium level during the first 30 days was 4.4 ± 0.3mEq/L. Hypokalemia was more frequent than hyperkalemia (3.1 versus 0.7 cases per 100 neonates). Dopamine (β = 0.584; p = 0.003) and norepinephrine (β = 0.811; p = 0.001) were associated with increased potassium levels, while dobutamine (β = -0.308; p = 0.029) was linked to reduced levels. Norepinephrine use was associated with the highest observed potassium concentrations (6.2 ± 2.1mEq/L). CONCLUSION: Catecholamines significantly influence serum potassium in neonates. Norepinephrine poses the most significant risk of hyperkalemia, whereas dobutamine tends to lower potassium levels. These findings emphasize the importance of potassium monitoring during vasoactive therapy in neonatal intensive care units.