Rebreathing expired gases from bedding: a cause of cot death?

• Published in: Archives of disease in childhood Vol. 69; no. 2; pp. 187 - 190
• Main Authors: Bolton, D P, Taylor, B J, Campbell, A J, Galland, B C, Cresswell, C
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health 01.08.1993; BMJ; BMJ Publishing Group LTD
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Asphyxia - complications; Bedding; Bedding and Linens; Biological and medical sciences; Carbon dioxide; Data Collection - methods; Emergency and intensive care: neonates and children. Prematurity. Sudden death; Humans; Infant; Intensive care medicine; Medical sciences; Models, Biological; Mortality; Pediatrics; Prone Position; Respiration - physiology; Respiratory system; SIDS; Sudden Infant Death - etiology; Sudden infant death syndrome; Human; Oxygen; Apnea; Lung function; Sudden death; Carbon dioxide; Risk factor; Exploration; Respiratory gas; Infant; Simulation model
• ISSN: 0003-9888; 1468-2044
• DOI: 10.1136/adc.69.2.187

The reported association of cot death and sleeping prone could be due to rebreathing of expired gases. A mechanical model simulating the respiratory system of an infant, exhaling warm humidified air with an end tidal carbon dioxide of 5%, has been used to investigate this. Some commonly used bedding materials caused an accumulation of carbon dioxide of 7% to over 10% with the model lying face down. This phenomenon persisted even with the head inclined at 45 degrees, but only on very soft materials, and could be a cause of cot death in a baby unresponsive to asphyxial blood gas changes. A coir fibre mattress allowed complete dispersal of exhalate as did a rubber sheet between any mattress and the covering sheet.