Obstructive sleep apnoea
Obstructive sleep apnoea (OSA) is caused by obstruction of the upper airway during sleep. Oxygen saturations drop, causing the patient to waken briefly. This does not happen when awake due to muscles of the upper airway. It is important as sleep is not refreshing, leading to reduction in performance during the day. The majority of cases are obese middle-aged men. It should be distinguished from central sleep apnoea where generally the mechanical interventions possible in obstructive sleep aponea worsen outcome.
Correctable predisposing factors
- Tonsilar enlargement
- Nasal obstruction (by increasing negative pressure within the airway)
- Respiratory depressants (alcohol, sedatives, opioid analgesics)
- Snoring (95%)
- Daytime sleepiness (90%)
- Morning headache
- Apnoeic episodes (often presenting feature due to partner's concern)
- Associated with mortality and morbidity from a wide range of conditions (see below)
Simple things first: reverse factors above, if possible. If this does not help, CPAP splints the airways open.
Obstructive sleep apnoea is associated with:
- Atrial fibrillation
- Cognitive dysfunction and compliance with treatment may improve this.
- ↑ Johansson K, Hemmingsson E, Harlid R, Trolle Lagerros Y, Granath F, Rössner S, Neovius M. Longer term effects of very low energy diet on obstructive sleep apnoea in cohort derived from randomised controlled trial: prospective observational follow-up study. BMJ (Clinical research ed.). 2011; 342:d3017.(Epub)
- ↑ Gonzaga C, Bertolami A, Bertolami M, Amodeo C, Calhoun D. Obstructive sleep apnea, hypertension and cardiovascular diseases. Journal of human hypertension. 2015 Mar 12.(Epub ahead of print) (Link to article – subscription may be required.)
- ↑ Martínez-García MÁ, Campos-Rodríguez F, Almendros I, Farré R. Relationship Between Sleep Apnea and Cancer. Archivos de bronconeumologia. 2015 Apr 2.(Epub ahead of print) (Link to article – subscription may be required.)
- ↑ Lin SW, Chou YT, Kao KC, Chuang LP, Yang CM, Hu HC, Huang CC, Yang CT, Chen NH. Immediate and Long-term Neurocognitive Outcome in Patients with Obstructive Sleep Apnea Syndrome After Continuous Positive Airway Pressure Treatment. Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India. 2015 Mar; 67(Suppl 1):79-85.(Link to article – subscription may be required.)