Obstructive Sleep Apnoea

Question 1

PC of OSA

Answer 1

loud snoring (according to others) 
periods of cessation of breathing in sleep 
daytime sleepiness 
morning headache
decreased libido 
decreased cognitive performance

Question 2

Past MHx , meds and SHx

Answer 2

HTN, COPD, HF, tonsillar enlargement or throat surgery

sleeping meds/hypnotics
diuretics and insulin may predispose to a bad sleep

EtOH and smoking
think - DRIVING, HEAVY MACHINERY

Question 3

DD for OSA

Answer 3

not enough sleep... 
Use of sedative drugs
Depression 
Idiopathic hypersomnolence 
Narcolepsy

Question 4

Medical conditions that increase risk?

Answer 4

pregnancy, HF, Renal disease, lung disease, CVA, acromegaly, hypothyroidism, PCOS, T2DM, parkinsons

Question 5

Examination

Answer 5

general
- BMI, acromegaly

peripheries/face

• Blood pressure
• Fundi for sings of HTN
• signs of hypothyroidism
• head/neck/mouth - uvular enlargement/macroglossia/.tonsillar hypertrophy, neck enlargement

Chest
Signs of pulmonary HTN
Cor pulmonale signs - cyanosis, tachycardia, JVP with prominent a and v waves, RV heave, loud P2 with pansystolic murumur (TR), hepatomegaly, oedema

Neurological
Myasthenia gravis and muscular dystrophy can casue OSA

Central causes of sleep apnea
Autonomic neuropathy
Brainstem lesions
Spinal cord disease

Question 6

Investigations

Answer 6

Pulse oximetry and video recordings of sleep
sleep study can be performed
TFTs
ECG - assess RV dysfunction
Epworth Sleepiness Scale
Apnea Hypopnoea index (AHI) = episodes of apnea/hours slept = mild 5-15, moderate 15-30, severe > 30

Question 7

treatment of OSA

Answer 7

Lifestyle: weight loss, reduce alcohol and smoking
Reverse underlying cause: Thyroid replacement, surgical correction of obstruction
Treat concominant diseases: HF, HTN, Asthma
CPAP for moderate to severe OSA
BiPAP for central sleep apnea (stroke)

Question 8

Complications of untreated OSA?

Answer 8

Pulmonary HTN –> RV dysfunction –> cor pulmonale –> type II resp failure

Risk of MVAs
Neuropsychiatric dysfunction
T2DM and NAFLD

OSA is also an independent risk factor for HTN