Bilirubin levels and severe retinopathy of prematurity in infants with estimated gestational ages of 23 to 26 weeks☆,☆☆
Section snippets
METHODS
We reviewed the charts of all infants born at 23 to 26 weeks EGA in our hospital between January 1990 and December 1996 who survived until discharge. Gestational age was assigned by best obstetric estimate and supported by prenatal ultrasonography in 90% of cases. For each infant, we calculated the average of all bilirubin levels obtained on each day and the overall average bilirubin level for days 1 to 15 of postnatal life. Bilirubin levels were measured as clinically indicated, and with
RESULTS
During the study period, 230 infants of 23 to 26 weeks EGA were born alive at our hospital, and 157 (68.3%) survived to discharge. We reviewed the charts of all surviving infants. One hundred fifteen infants (73.2%) comprised the mild ROP group: immature retinas (n = 34, 22%), stage 1 (n = 12, 8%), stage 2 (n = 49, 31%), stage 3 (n = 20, 13%). Forty-two (26.8%) infants had severe ROP (≥stage 3+). There were significant differences between the groups in EGA, birth weight, days of mechanical
DISCUSSION
ROP is a frequently seen but poorly understood morbidity in extremely low birth weight infants. A number of risk factors have been described, but as yet there is no common underlying mechanism that completely explains why ROP develops in premature infants. Oxygen radical formation during periods of hypoxia and re-oxygenation has been proposed as one possible etiology. This theory is intriguing and is especially important in light of the evidence that suggests that premature infants have reduced
Acknowledgements
The authors greatly appreciate the assistance of Mamtha Balasubramanian, MS, William Beaumont Hospital Research Institute Bio-statistician.
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Cited by (0)
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Reprint requests: Mitchell H. DeJonge, MD, William Beaumont Hospital, 3601 W 13 Mile Rd, Royal Oak, MI 48073.
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0022-3476/99/$8.00 + 0 9/22/99111