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Published on: December 22, 2016

Ventilatory drive and the apnea-hypopnea index in six-to-twelve year old children

Ralph F Fregosi1, Stuart F Quan, Andrew C Jackson

  • 1Department of Physiology, The University of Arizona, Tucson, USA. Fregosi@u.arizona.edu

BMC Pulmonary Medicine
|May 1, 2004
PubMed

Insights

Children with sleep-disordered breathing show a weaker response to low oxygen levels and higher resting carbon dioxide levels. This suggests a link between reduced hypoxic ventilatory drive and CO2 retention in pediatric obstructive sleep apnea.

Area of Science:

  • Pediatric Pulmonology
  • Sleep Medicine
  • Respiratory Physiology

Background:

  • Sleep-disordered breathing, characterized by the obstructive apnea hypopnea index (OAHI), is prevalent in children.
  • Understanding the physiological underpinnings of ventilatory control in children with sleep-disordered breathing is crucial.

Purpose of the Study:

  • To investigate the relationship between ventilatory drive during hypoxia and hypercapnia and the obstructive apnea hypopnea index (OAHI) in children.
  • To determine if reduced ventilatory drive or altered resting CO2 levels are associated with sleep-disordered breathing severity in pediatric populations.

Main Methods:

  • Fifty children aged 6-12 years underwent unattended polysomnography to determine their OAHI.
  • Ventilatory drive was assessed during wakefulness by measuring mouth occlusion pressure (P0.1) under varying levels of oxygen and carbon dioxide.
  • The hypoxic and hypercapnic ventilatory drives were calculated as the slope of P0.1 versus end-tidal O2 (PETO2) or CO2 (PETCO2).

Main Results:

  • A significant inverse correlation was found between hypoxic ventilatory drive and OAHI (r = -0.31, P = 0.041).
  • Hypercapnic ventilatory drive did not show a significant correlation with OAHI (r = -0.19, P = 0.27).
  • Resting end-tidal CO2 (PETCO2) was positively correlated with OAHI, indicating CO2 retention in children with higher OAHI values.

Conclusions:

  • In awake children, the OAHI is inversely related to hypoxic ventilatory drive and positively related to resting PETCO2.
  • These findings suggest that reduced hypoxic ventilatory drive and resting CO2 retention are associated with sleep-disordered breathing in children aged 6-12.
  • Further research is needed to confirm if these physiological alterations contribute to the severity of sleep-disordered breathing in this age group.
Abstract

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