Effect on CO₂ Dispersal Rate of Commercial Products Marketed to Reduce Sudden Infant Death Syndrome Risk

Abstract 2067 Poster Session IV, Tuesday, 5/4 (poster 188)

Background: Less prone sleeping has been accompanied by lower SIDS rates. One explanation may be that non-prone infants are not rebreathing exhaled air from underlying bedding. Despite this risk, many infants still sleep prone. New products claim to reduce rebreathing risk for prone infants.

Methods: 5 commercial sleep products were studied. "Active" systems: Halo Sleep Systems™, Sleep Guardian™; "Passive" systems: Breathe Easy™,Bumpa Bed™, Kid Safe Baby Air™. Products were tested for their ability to hasten CO₂ dispersal using a biomechanical model of a mannequin placed face-down on the test surface and "ventilated" with a syringe containing 5% CO₂ (J Appl Physiol 78 p 740). The t½ for CO₂ dispersal from the mannequin-bedding ensemble quantitates rebreathing potential of the bedding. Face-down studies were compared to conventional bedding and to a control with the mannequin face-to-side. Each product was tested with the face down and underlying cover 1)taut, 2)wrinkled, and 3)taut but mannequin arm at side of head. Ten repetitions were done with each product under the three simulations.

Results: t½ differed among products for all three simulations (ANOVA; all p<0.0001). All sleep systems caused significant increases in t½ compared to the control system except for the Halo System (sheet taut and sheet wrinkled). In many instances, t½ exceeded thresholds associated with rise in PaCO₂ (≥21.1 s) or with lethality(>24.0 s). All systems exceeded thresholds under one or more simulations except the Halo System. (Table)

Table 1 No caption available

Conclusions: 1)Standard, firm bedding and most items said to prevent rebreathing, do little to reduce, or may worsen, CO₂ trapping. 2)Most cannot be recommended for infants who might turn their face down. 3)No product completely prevented rebreathing, but the Halo Sleep System maintained CO₂ dispersal at rates preventing increases in PaCO₂. 4)Industry standards for rebreathing based on biomechanical models should be developed.