Impact of Caffeine on Outcomes of Small for Gestation (SGA) Infants of ≤29 Weeks of Gestation.
Background: Caffeine, a non-specific adenosine receptor (A1AR) antagonist, has been shown to be effective in treating apnea of prematurity. Recently, a large trial showed that caffeine also helps to reduce the incidence of oxygen requirements at 36 weeks corrected gestational age (CLD). Impact of caffeine specifically in SGA preterm infants, who are most vulnerable, is not reported.
Purpose: To determine the impact of caffeine on CLD incidence in SGA infants of ≤ 29 weeks of gestation.
Methods: A retrospective chart review of all infants born ≤29 weeks gestation from 2007 to 2011, who survived to discharge or 36 weeks corrected gestational age. Information about birth weight, gestational age, sex, day of life when caffeine was started, average caffeine levels, duration of mechanical ventilation (DV), PDA, infection, CLD, PVL, NEC and ROP were obtained and analyzed. We compared CLD, length of stay (LOS), oxygen at discharge (O2D) and DV between the study group (caffeine started ≤3 days of life [CDOL3]) and the control group (caffeine started ≥4 days of life [CDOL4]). Caffeine was prescribed at the discretion of the attending neonatologist for either periextubation prophylaxis or for treatment of apnea. Independent sample t-tests and Mann Whitney U tests were used where applicable. P value of <0.05 was considered significant.
Results: We reviewed 222 charts; 199 met the inclusion criteria and 23 were omitted due to death or transfer before 36 weeks corrected gestational age. CLD, LOS, and DV were significantly less in CDOL3 group compared to CDOL4.
SGA infants accounted for 12.5% of the study population, 52% had CLD, compared to 20.1% of AGA infants (P= <0.001). Twenty four percent% of SGA vs 5.8% of AGA infants needed O2D (P = 0.002). Mean LOS in SGA infants was 110.3 days (SD 62.1) vs 72.8 (SD 30.3) for those AGA (P = <0.001). Mean DV in SGA infants was 42 days (SD 48) vs 16 (SD 23), P= 0.002.
Age of caffeine initiation: Ninety percent of the SGA infants in the late caffeine group (CDOL4) developed CLD compared to 25.4% AGA preterm infants in CDOL4 (P = <0.001). CLD, LOS and DV comparisons between SGA and AGA infants according to age of caffeine initiation are shown below.
Conclusions: SGA preterm infants are at highest risk for CLD. Early caffeine was strongly associated with a decreased incidence of CLD and shorter LOS and DV in SGA infants. Initiating caffeine early may be more important in SGA than in AGA preterm infants.