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Apnea of prematurity: caffeine dose optimization.

OBJECTIVES
The primary objective was to evaluate the correlation between maintenance dose and response rates in neonates less than 28 weeks gestational age. Secondary objectives included clinical indicators of response (number of weight adjustments, dose increases, and mini-loads) and tachycardia associated with caffeine therapy.


METHODS
This study was a retrospective analysis of neonates admitted to the North Carolina Children's Hospital from August 2009 to August 2011. Patients included were less than 28 weeks postmenstrual age and were treated with caffeine for apnea of prematurity. Patients were excluded if they were older than 28 weeks postmenstrual age, receiving caffeine therapy for other indications, or experiencing apnea from other conditions, or if therapy was initiated more than 7 days after birth.


RESULTS
A total of 89 neonates with a mean birth weight of 0.844 kg (range: 0.391 to 1.306 kg) and median gestational age of 26 2/7 weeks (range: 23 to 27 6/7 weeks) were evaluated. The median initial maintenance dose of caffeine citrate was 7.9 mg/kg/day, and 94.1% of neonates receiving ≤7.9 mg/kg/day required a clinical intervention during therapy compared with 76.3% in those receiving >7.9 mg/kg/day. Absolute incidence of tachycardia was low, and caffeine levels collected ranged from 16.6 to 34.4 μg/mL.


CONCLUSIONS
In neonates less than 28 weeks gestational age, doses of caffeine citrate greater than 7.9 mg/kg/day are safe and are associated with a decreased need for clinical interventions.