Beneficial effect of inhaled CO2 in a patient with non-obstructive sleep apnoea

J Neurol. 1993 Nov;241(1):45-8. doi: 10.1007/BF00870671.


A 63-year-old man with severe non-obstructive sleep apnoea (apnoea index 28; apnoea duration 45-60s; O2 saturation between 72% and 98%), who did not respond to common modes of treatment, was successfully treated with CO2. A tent was perfused with compressed air (6 1/min) and increasing amounts of CO2. A concentration of 3% CO2 (180 ml/min) was sufficient to raise the PaCO2 above apnoea threshold and to suppress apnoeas completely. As a result, O2 saturation remained normal throughout the whole night and the symptoms of sleep apnoea disappeared. We hypothesize that the PCO2 ventilatory drive was intact in our patient and that hypocapnia was the major factor causing the non-obstructive sleep apnoea syndrome. Administration of CO2 with a constant flow system could be a safe and easy alternative for patients with non-obstructive sleep apnoea syndrome who present with hypocapnia and an intact respiratory feedback control system.

Publication types

  • Case Reports

MeSH terms

  • Administration, Inhalation
  • Carbon Dioxide / administration & dosage
  • Carbon Dioxide / therapeutic use*
  • Cheyne-Stokes Respiration / drug therapy
  • Cheyne-Stokes Respiration / etiology
  • Feedback
  • Heart Failure / complications
  • Humans
  • Hypertension / complications
  • Hypocapnia / complications
  • Hypocapnia / drug therapy*
  • Male
  • Middle Aged
  • Obesity / complications
  • Sleep Apnea Syndromes / drug therapy*
  • Sleep Apnea Syndromes / etiology
  • Sleep Apnea Syndromes / physiopathology


  • Carbon Dioxide