Open AccessSerum Theophylline Concentrations in very Preterm Neonates Receiving Intravenous Aminophylline for Apnea
Author(s) -
Pimol Wongsiridej,
Sopapan Ngerncham,
Siripa Usaha,
Weerawadee Chandranipapongse,
Tim R. Cressey
Publication year - 2021
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.125
H-Index - 2
ISSN - 2228-8082
DOI - 10.33192/smj.2021.68
Subject(s) - aminophylline , medicine , theophylline , apnea of prematurity , loading dose , gestational age , maintenance dose , anesthesia , dosing , confidence interval , univariate analysis , apnea , pregnancy , multivariate analysis , biology , genetics
Objective: To determine the percentage of neonates who achieved therapeutic theophylline level (TTL) after receiving standard IV loading/maintenance aminophylline doses. To assess factors associated with achieving therapeutic theophylline concentrations and to describe adverse effects of aminophylline. Materials and Methods: This was a pilot, cross-sectional study. Preterm neonates ≤34 weeks’ gestation for which aminophylline was indicated for treatment of apnea were enrolled. Standard IV aminophylline dosage is 8 mg/ kg loading dose, followed by 1.5 mg/kg maintenance dose every 8 hours. Serum theophylline concentrations were measured prior to the 8th maintenance dose. Descriptive statistics, univariate and multivariate analyses were performed. Results: Twenty-five neonates (52% female) were enrolled: mean (standard deviation) gestational age and birth weight were 30.4 (2) weeks and 1,277 (415) grams, respectively. Aminophylline was initiated at a median (25%tile, 75%tile) postnatal age of 4 (1, 8) days. Baseline heart rate prior to the loading dose was 153 (13) beats-per-minute. Sixty percent of neonates achieved a therapeutic theophylline level. In the univariate analysis, being male and postnatal age ≤5 days were associated with successfully achieving a TTL. After adjusting for gender, postnatal age ≤5 days was the only factor associated with achieving a TTL (adjusted odds ratio 17.7, 95% confidence interval: 1.9, 164.4). Tachycardia and feeding intolerance were observed in 44% and 24% of neonates, respectively. Conclusion: Current IV aminophylline dosing conditions in Thailand achieved TTL in approximately two-thirds of neonates, suggesting therapeutic drug monitoring is beneficial for guiding dosing. A higher maintenance dose could be considered for neonates older than 5 days.