Arousal induced hypocapnia does not reduce genioglossus activity in obstructive sleep apnea: Arousal induced hypocapnia in OSA: muscle effects

AuthorsCori, J. M.
Thornton, T.
O'Donoghue, F. J.
Rochford, P. D.
White, D. P.
Trinder, J.
Jordan, A. S.
TypeJournal Article (Original Research)
PubMed ID28419356
Year of Publication2017
Download zsx057.pdf (1.1 MB)
AbstractStudy Objectives:
To determine whether arousals that terminate obstructive events in obstructive sleep apnea (OSA) (1) induce hypocapnia and (2) subsequently reduce genioglossus muscle activity following the return to sleep.
Thirty-one untreated patients with OSA slept instrumented with sleep staging electrodes, nasal mask and pneumotachograph, end-tidal CO2 monitoring, and intramuscular genioglossus electrodes. End-tidal CO2 was monitored, and respiratory arousals were assigned an end-arousal CO2 change value (PETCO2 on the last arousal breath minus each individual's wakefulness PETCO2). This change value, in conjunction with the normal sleep related increase in PETCO2, was used to determine whether arousals induced hypocapnia and whether the end-arousal CO2 change was associated with genioglossus muscle activity on the breaths following the return to sleep.
Twenty-four participants provided 1137 usable arousals. Mean ± SD end-arousal CO2 change was −0.2 ± 2.4 mm Hg (below wakefulness) indicating hypocapnia typically developed during arousal. Following the return to sleep, genioglossus muscle activity did not fall below prearousal levels and was elevated for the first two breaths. End-arousal CO2 change and genioglossus muscle activity were negatively associated such that a 1 mm Hg decrease in end-arousal CO2 was associated with an ~2% increase in peak and tonic genioglossus muscle activity on the breaths following the return to sleep.
Arousal-induced hypocapnia did not result in reduced dilator muscle activity following return to sleep, and thus hypocapnia may not contribute to further obstructions via this mechanism. Elevated dilator muscle activity postarousal is likely driven by non-CO2-related stimuli.

< More publications


Interstitial lung disease (ILD) is a chronic lung condition that causes stiff lungs and restricts sufferers from taking a deep breath. Exercise in a gym, such as walking or riding a bike, can help make...


Each year in Australia 260 people sustain a SCI, with over half losing full function in their arms and legs (quadriplegia). In addition to the primary disability, there is a very high rate of Obstructive...

Notch monitoring in sleepNOTCH MONITORING IN SLEEP

Sleep apnea is a condition where breathing is abnormal during sleep. There are two main forms of sleep apnea: obstructive and central. For obstructive sleep apnea, breathing is reduced because the airway...

Do you have Spinal cord injury? Tired?  Get treated!DO YOU HAVE SPINAL CORD INJURY? TIRED? GET TREATED!

Melbourne researchers have found that 80 percent of people with quadriplegic spinal injuries have sleep apnoea. It's having a big effect on their lives but they don't know they have it, and they don't know it can be treated.

World 1st heavy vehicle driver fatigue study releasedWORLD 1ST HEAVY VEHICLE DRIVER FATIGUE STUDY RELEASED

The National Transport Commission (NTC) and the Cooperative Research Centre for Alertness, Safety and Productivity (Alertness CRC) have released the results of what is hailed as a world-first study into heavy vehicle driver fatigue.

AAMRI Election Statement released on 25th March 2019AAMRI ELECTION STATEMENT RELEASED ON 25TH MARCH 2019

AAMRI released its election statement calling on politicians to commit to three main priorities: ensuring the MRFF reaches $20 billion by 2020-21, provide continued strong support for the NHMRC, and develop sustainable and rewarding career pathways.

Portrait unveiled at Canberra's Parliament HousePORTRAIT UNVEILED AT CANBERRA'S PARLIAMENT HOUSE

IBAS Director Anna Burke had barely got into the swing of her speech at the unveiling of her portrait at Canberra's Parliament House when the ringing of bells caused half her audience to hurry away.

Institute for Breathing and Sleep

Level 5, Harold Stokes Building, Austin Hospital
145 Studley Road
Heidelberg, Victoria, 3084

(03) 9496 5390

Email Us