Obstructive Sleep Apnoea

Sleep apnoea can be divided into central (rare) and obstructive (common)

Key features

• Excessive day time somnolence - use Epworth score
• Fatigue, Poor concentration, Weariness is the main complaint
• Heavy Snoring at night with periods of witnessed apnoea
• Nocturia, Morning headaches, Non-satisfying sleep

Aetiology - upper airway collapse

• There is usually recurrent occlusion at the pharyngeal level during sleep
• Possibly due to negative pressure generated through inhalation
• Typically obese males with large collar sizes who snore loudly
• Smoking is a risk factor
• Is associated with increased risk of single-vehicle Road traffic accidents
• Partner describes periods of apnoea during sleep
• Avoid sedation and alcohol

Investigations

• Sleep lab studies show profound drops in PO2 and measure O2 Saturation, EEG, EMG, oronasal airflow and respiratory effort and snoring
• There are usually > 15 apnoea's (10 seconds or more) per hour
• Epworth sleepiness scale is useful

Risks of Sleep apnoea

• Systemic hypertension and mild pulmonary hypertension
• Associated with MI/Arrhythmias/Stroke?
• Road traffic accidents

Management

• Avoid alcohol, smoking, sedatives. Aim for weight loss
• Treatment with CPAP reduces self-reported crashes