Thomas Rossor1,2, Kamal Ali3, Ravindra Bhat3, Rebecca Trenear1,2, Gerrard Rafferty4, Anne Greenough5,6,7. 1. MRC and Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London, UK. 2. Department of Women and Children's Health, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK. 3. Neonatal Intensive Care Centre, King's College Hospital NHS Foundation Trust, London, UK. 4. School of Basic and Medical Biosciences, King's College London, London, UK. 5. MRC and Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London, UK. anne.greenough@kcl.ac.uk. 6. Department of Women and Children's Health, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK. anne.greenough@kcl.ac.uk. 7. NIHR Biomedical Centre at Guy's and St Thomas' NHS Foundation Trust, King's College London, London, UK. anne.greenough@kcl.ac.uk.
Abstract
BACKGROUND: Maternal smoking, substance misuse in pregnancy and prone sleeping increase the risk of sudden infant death syndrome (SIDS). We examined the effect of maternal smoking, substance misuse and sleeping position on the newborn response to hypoxia. METHODS: Infants born between 36 and 42 weeks of gestational age underwent respiratory monitoring in the prone and supine sleeping position before and during a hypoxic challenge. Minute ventilation (MV) and end-tidal carbon dioxide (ETCO2) levels were assessed. RESULTS: Sixty-three infants were studied: 22 controls, 23 whose mothers smoked and 18 whose mothers substance-misused and smoked. In the supine position, baseline MV was higher and ETCO2 levels were lower in infants of substance-misusing mothers compared to controls (p = 0.015, p = 0.017, respectively). Infants of substance-misusing mothers had a lower baseline MV and higher ETCO2 levels in the prone position (p = 0.005, p = 0.004, respectively). When prone, the rate of decline in minute ventilation in response to hypoxia was greater in infants whose mothers substance-misused and smoked compared to controls (p = 0.002) and infants of smoking mothers (p = 0.016). CONCLUSION: The altered response to hypoxia in the prone position of infants whose mothers substance-misused and smoked in pregnancy may explain their increased vulnerability to SIDS.
BACKGROUND: Maternal smoking, substance misuse in pregnancy and prone sleeping increase the risk of sudden infant death syndrome (SIDS). We examined the effect of maternal smoking, substance misuse and sleeping position on the newborn response to hypoxia. METHODS: Infants born between 36 and 42 weeks of gestational age underwent respiratory monitoring in the prone and supine sleeping position before and during a hypoxic challenge. Minute ventilation (MV) and end-tidal carbon dioxide (ETCO2) levels were assessed. RESULTS: Sixty-three infants were studied: 22 controls, 23 whose mothers smoked and 18 whose mothers substance-misused and smoked. In the supine position, baseline MV was higher and ETCO2 levels were lower in infants of substance-misusing mothers compared to controls (p = 0.015, p = 0.017, respectively). Infants of substance-misusing mothers had a lower baseline MV and higher ETCO2 levels in the prone position (p = 0.005, p = 0.004, respectively). When prone, the rate of decline in minute ventilation in response to hypoxia was greater in infants whose mothers substance-misused and smoked compared to controls (p = 0.002) and infants of smoking mothers (p = 0.016). CONCLUSION: The altered response to hypoxia in the prone position of infants whose mothers substance-misused and smoked in pregnancy may explain their increased vulnerability to SIDS.
Authors: Leonel F Pérez-Atencio; Ana M Casarrubios; José M Ibarz; Juan A Barios; Cristina Medrano; David Pestaña; David L Paul; Luis C Barrio Journal: Physiol Rep Date: 2021-11