Reduced Severity of Oxygen-Induced Retinopathy in Kittens Recovered in 28% Oxygen

Abstract

Chronic hypoxemia adversely affects the retinopathy observed in kittens after a hyperoxic exposure (80% oxygen) in the 1st wk of life. To test the converse hypothesis, 55 kittens were randomly assigned to recover in room air (21%) or 28% inspired oxygen after a 65-h hyperoxic exposure. At 4 wk of age, the retinopathy was found to be less severe in the 28% recovered kittens, severity score 3.0 ± 3.3 (mean ± SD), than in the room air recovered animals, severity score 5.7 ± 3.3, p < 0.01. This finding suggests that the clinical practice of restricted oxygenation in premature infants warrants reevaluation.