Snoring & OSA Flashcards
Snoring
- Sound caused by vibration of walls of air passages and throat when they partially collapse during sleep
- When awake, airway muscles keep air passages open
- During sleep, they relax, causing collapse of air passages during sleep
- Turbulent airflow through upper airway
OSA
- Apnoea: Stoppage of breathing
- Hypopnoea: ↓ in breathing
- Repeated upper airway closure during sleep
- Choking caused by body’s own tissues causes O2 levels to ↓ –> Sensed by brain which wakes itself temporarily to open airway to breathe before falling back to sleep again –> Obstruction occurs again and cycle repeats –> Disrupts sleep –> Poor sleep quality
- Patient usually unaware of how many times choking and awakenings occur during sleep
Causes/RFs of snoring & OSA
- Inherited: Oriental facial skeleton more predisposed (Craniofacial abnormalities main cause):
- Smaller mandible –> Relatively big tongue –> More likely to cause obstruction
- Shorter anterior cranial base –> Flatter face –> Retrusive maxilla - Acquired
- Nasal obstruction ↑ airway resistance (nasal airway, pharyngeal airway)
- Enlarged tonsils and adenoids
- Metabolic syndrome can cause OSA and vice versa, same risk factors
- ↑ age as laxity of tissues in air passages causes ↑ collapsibility - Central causes
- Children:
- Often seen in Down’s syndrome
- Enlarged tonsils and adenoids
- Uncontrolled nasal allergy
What can worsen OSA?
Being overly tired doesn’t cause but worsens snoring or OSA
When body catches up with lost sleep, there’s greater % of deep sleep and REM sleep during sleep period, where snoring and OSA are worse
Symptoms of OSA
- Asymptomatic
- Daytime symptoms
- Nighttime symptoms
- Symptoms in children
Daytime symptoms of OSA
- Unrefreshing sleep
- Excessive daytime sleepiness/ Daytime somnolence
- Fatigue
- Waking up with dry mouth or throat (Mouth breathing)
- Morning headache (Hypopnea causes ↑ cerebral CO2 causes intracerebral vessels to vasodilate, ↑ICP)
- Depression/ Anxiety
- Poor memory and concentration
- Motor vehicle accidents
Nighttime symptoms of OSA
- Loud snoring that disturbs sleeping partners
- Choking during sleep (Most reliable symptom)
- Frequent awakenings
- Frequent nocturia (Anti-natriuretic peptide is a diuretic released due to ↑ pressure on thoracic cavity when the patient gasps for air at night –> atrium is being stretched and thinks that it’s overstretched due to ‘fluid overload’ –> nocturia)
- Poor ability to stay asleep throughout night (Sleep maintenance insomnia)
***DON’T GIVE BENZODIAZEPINES (it relaxes muscles and worsens OSA) - Poor libido
Symptoms of OSA in children
- Restless sleep/sleep with hyperextended neck
- Sweating during sleep (Using a lot of energy to breathe)
- Secondary enuresis
- AR
- Mouth breathing (Nasal and adenoid obstruction)
- ADHD (OSA –> 2° ADHD!!!)
- Poor attention span and school performance
- Poor physical and mental growth and development
- Failure to thrive (Disruption of sleep interrupts GH secretion during deep sleep)
*May not snore if very young cause not enough pressure to generate vibrations
Complications of untreated OSA
- ↑ risk of developing HTN, DM (cortisol released), heart disease, heart failure, atrial fibrillation and stroke
- Cor pulmonale
- Poor sleep quality causes excessive daytime sleepiness –> Accidents at workplace if one is operating heavy machinery or on road if one is driving
- Social problems, embarrassing, disturbing to sleeping partners, strain relationships and ↑ risk of divorce in married couples
What is required to diagnose OSA?
Polysomnography
What results of polysomnography indicate OSA?
Apnea hypoapnea index or Respiratory disturbance index >/= 5 AND symptoms
- Mild: 5-14/h
- Moderate: 15-29/h
- Severe: ≥30/h
AHI or RDI >/= 15 if NO symptoms
Children: AHI >/= 1
If sleep study is -ve for OSA in a snorer, diagnosis is?
Primary snoring, i.e. snoring in absence of airway obstruction
Management for OSA
- Primary snoring can be left untreated as long as it doesn’t cause social problems
Goal is to manage the OSA and underlying cause:
For OSA, I will split into:
1st line therapy vs adjuncts vs surgical
GOLD, 1st line therapy: Continuous positive airway pressure
+ve air pressure stents airway open preventing collapse, snoring and stoppage of breathing
Mild S/E:
- Dry mouth or throat
- Blocked nose or ears
- Minor skin ulcers
- Non-compliance
- Positional therapy
- Dental splints (mandibular advancement device)
- Devices worn during sleep to maintain lower jaw and teeth in protruded position (Pull mandible and base of tongue forward) –> Enlarge air space behind tongue and put air passage tissues in greater tension –> ↓ tendency for airway walls to collapse
S/E:
- Excessive salivation during sleep
- Jaw opening problems
- Malocclusion - Patient education
- lifestyle measures (smoking, alcohol, weight)
- nasal breathing - Surgery
- Uvulopalatopharyngeal surgery
- Maxillomandibular surgery
- Hypoglossal nerve stimulation (new advancement especially if tongue is the main cause of osa)
What criteria is used to predict probability of OSA?
STOP-BANG
Snoring
Tiredness
Observed apneas
High BP
BMI > 35
Age > 50
Neck circumference > 40
Gender: Male
3 or more = moderate to severe risk of OSA
What scale is used to predict severity of excessive daytime sleepiness?
Epworth sleepiness scale
11-24 = excessive (abnormal) daytime sleepiness