Acetazolamide in Critically Ill Neonates and Children With Metabolic Alkalosis

Background: Acetazolamide is an option for hypochloremic metabolic alkalosis, but there are limited reports in children. Objective: To describe the acetazolamide regimen and outcomes in critically ill children with metabolic alkalosis. Methods: This was a descriptive, retrospective study of patients <18 years of age who received ≥3 doses of acetazolamide for metabolic alkalosis (ie, pH > 7.45 and bicarbonate [HCO₃] > 26 mEq/L). Patients receiving other treatments for metabolic alkalosis within 24 hours of acetazolamide were excluded. The primary objective was to identify the mean dose and duration of acetazolamide. Secondary objectives were to determine the number of patients with treatment success (ie, serum HCO₃ 22-26 mEq/L) and occurrence of adverse events. Results: Thirty-four patients were included for analysis, the median age was 0.25 years (range = 0.05-12 years). The acetazolamide regimen included a mean dose of 4.98 ± 1.14 mg/kg for a mean number of 6.1 ± 5.3 (range = 3-24) doses. The majority (70.6%) received acetazolamide every 8 hours. Treatment success was achieved in 10 (29.4%) patients. Statistically significant differences were noted between the pre-acetazolamide and post-acetazolamide pH and HCO₃, 7.51 ± 0.05 versus 7.37 ± 0.05 (P < .001) and 39.4 ± 6.1 mEq/L versus 31.4 ± 7.5 mEq/L (P < .001), respectively. Conclusions: This is the first study to evaluate acetazolamide dosing for metabolic alkalosis in children with and without cardiac disease. Acetazolamide treatment resulted in improved HCO₃, but the majority of patients did not achieve our definition of treatment success. Future studies should elucidate the optimal acetazolamide regimen.