Determination of plasma salbutamol concentrations after nebulization in a pediatric emergency department

To partially validate the methodology for determining salbutamol in human plasma through high-efficiency liquid chromatography and fluorescence detection. To analyze plasma salbutamol concentrations in a group of pediatric patients with indication for nebulization in the emergency room.

Analytical, prospective cross-sectional case series. Fifteen patients aged 12 to 37 months with a diagnosis of acute asthma crisis were selected at the Pediatric Emergency Service at Hospital da Criança Santo Antônio - Complexo Hospitalar Santa Casa, Porto Alegre, Brazil. The patients were treated following the unit's routine for the management of acute asthma crises: nebulization with salbutamol (flow rate of 6-8 L/min) (0.15 mg/kg) suspended in 4 mL of 0.9% saline solution. Nebulization was administered sequentially, three times, at 20 minute intervals. All patients were given prednisolone orally (1 mg/kg) concurrently with the nebulizations.

Plasma concentrations exhibited great variability in acute asthma crisis patients given three nebulizations of salbutamol (0.15 mg/kg). The mean level in plasma was 12.09 +/- 10.8 ng/mL, with a median of 8.9 ng/mL (IQ25-75% 2.75-17.65). The sample's coefficient of variation was 92.4%.

Post-inhalation plasma salbutamol concentrations exhibit great variation in the pediatric population, as seen in other studies. The possible causes and implications of this finding remain the subject of disagreements and of further assessments.