Hypoxic and hypercapnic events in young infants during bed-sharing.

OBJECTIVES To identify desaturation events (arterial oxygen saturation [Sao(2)] <90%) and rebreathing events (inspired carbon dioxide (CO(2)) >3%), in bed-sharing (BS) versus cot-sleeping (CS) infants. METHODS Forty healthy, term infants, aged 0 to 6 months who regularly bed-shared with at least 1 parent >5 hours per night and 40 age-matched CS infants were recruited. Overnight parent and infant behavior (via infrared video), Sao(2), inspired CO(2) around the infant's face, and body temperature were recorded during sleep at home. RESULTS Desaturation events were more common in BS infants (risk ratio = 2.17 [95% confidence interval: 1.75 to 2.69]), associated partly with the warmer microenvironment during BS. More than 70% of desaturations in both groups were preceded by central apnea of 5 to 10 seconds with no accompanying bradycardia, usually in active sleep. Apnea >15 seconds was rare (BS infants: 3 events; CS infants: 6 events), as was desaturation <80% (BS infants: 3 events; CS infants: 4 events). Eighty episodes of rebreathing were identified from 22 BS infants and 1 CS infant, almost all preceded by head covering. During rebreathing, Sao(2) was maintained at the baseline of 97.6%. CONCLUSIONS BS infants experienced more oxygen desaturations preceded by central apnea, partly related to the warmer microenvironment. Rebreathing occurred mainly during bed-sharing. Infants were at low risk of sudden infant death syndrome and maintained normal oxygenation. The effect of repeated exposure to oxygen desaturation in vulnerable infants is unknown as is the ability of vulnerable infants to respond effectively to rebreathing caused by head covering.