Sleep apnoea Flashcards
Explain how obstructive sleep apnoea occurs due to anatomy
• Approximately 8.3% of the Australian adult population is diagnosed with OSA
• This occurs when the muscles in the back of the throat relax. These muscles support the soft palate, the uvula, the tonsils, the side walls of the throat and the tongue
• When the muscles relax the airway narrows or closes as you breathe in.
• You can’t get enough air, which can lower the oxygen level in your blood. Your brain senses your inability to breathe and briefly rouses you from sleep so that you can reopen your airway. This awakening is usually so brief that you don’t remember it.
• You might snort, choke or gasp. This pattern can repeat itself five to 30 times or more each hour, all night, impairing your ability to reach the deep, restful phases of sleep.
In healthy people, the muscles in the upper airway are strong enough to prevent muscle collapse.
• However in those with OSA, the muscles are unable to maintain integrity due to anatomical and non- anatomical reasons.
Explain the process of how OSA is diagnosed
Patient is hooked up with various wires which measures:
- electroencephalography (EEG; brainwave activity)
- electrooculogram (EOG; eye movement)
- electromyogram (EMG)
- airflow (nasal and/or oral)
- electrocardiography,
- pulse oximetry,
- respiratory effort (thoracic/abdominal),
- snore microphone
video monitoring of various
- body positions
List the diagnostic criteria for OSA
· Cessation of breathing (apnea) or airflow reduction (hypopnea - 30-50%)lasting ≥10 s
· 5 times per hour of sleep
· that is associated with cortical sleep arousals and/or oxygen desaturation (3% or greater)
· with continued respiratory efforts
List the OSA CLASSIFICATION for the total number of apneic and hypopneic episodes per hour of sleep in adults and children
The total number of apneic and hypopneic episodes per hour of sleep
Children:
Mild: 1-5
Moderate: 5-10
Severe: >10
Adult:
Mild: 5 - 15
Moderate: 15 - 30
Severe: >30
Define central sleep apnoea
Central sleep apnoea (CSA) is characterized by a lack of respiratory effort during cessations of airflow.
List 8 symptoms of OSA
· Un-refreshing sleep · Excessive daytime sleepiness (somnolence) · Fatigue · Morning headaches, · Dry mouth, sore throat · Reduced concentration and memory loss · Irritability · Nocturia
List the 10 aetiologies of OSA
· Genetics - Upper airway anatomy, arousal threshold and ventilatory control · Males · Older age · Ethnicity - Asian and African Americans · Obesity · Alcohol use · Smoking · Upper airway collapsibility · Muscle tone during sleep · Nasal congestion/ allergies
List 6 diseases that are comorbidities with OSA
· Hypertension · Periodontitis (higher prevalence) · Cardiovascular disease · Stroke · Metabolic syndrome (type II diabetes) · Depression/ cognitive impairment
List the 7 oral, head and neck anatomical changes that accompany OSA
· Narrow maxilla, · Decreased mandibular and maxillary lengths, Skeletal retrusion, mandible maxilla · Increased mandibular plane angle, · Long face, · Low hyoid position · Short cranial base
Briefly explain the link between periodontitis and OSA
· Two diseases have some common risk factors and underlying systemic inflammatory status
· Coexistent OSA may increase the presence and severity of periodontitis by contributing to increased systemic inflammation
· Mouth breathing - Dry mouth, commonly experienced by most snorers and mouth breathers with OSA may exacerbate the bacterial overgrowth and plaque formation, as bacterial clearance is impaired.
List the various forms of management for OSA
Medical
· Continuous Positive Airway Pressure (CPAP), although gold standard, has low long-term compliance
· Conservative Measures (Lifestyle changes, positional therapy
· Pharmacotherapy
Oral appliances
· Mandibular Advancement Splint (MAS)
· Tongue Stabilizing Device (TSD)
Surgical
· Soft tissue
· Skeletal
List the 8 disadvantages of a CPAP machine
· Noise · Cumbersome · Pressure intolerance · Air leak · Nasal/oral dryness · Nasal stuffiness · Sneezing · Swallowing air
Explain mandibular advancement splints, and list the 5 main advantages of it
Recommended as a first line therapy for mild to moderate OSA. It works by It works by temporarily moving the jaw, hyoid bone and tongue forward, which reduces throat constriction and prevents sleep apnoea and snoring. Moving the tongue forward increases airway space. In addition, the muscles supporting the tongue are engaged to pulled the tongue forward, while the palatoglossal arch stretches allowing an increase in airway space. Used in more severe cases that cannot tolerate CPAP.
· Small · Portable · Not noisy · Less expensive · Greater patient compliance
List 4 considerations prior to recommending a MAS
· Evaluate periodontal health
· Restoration need
· TMD
· Explain side effects
List the 8 side effects of MAS
· Bite change in the morning
· Long term reduced overjet and overbite
· Altered molar relationship
· Change in alignment
Initial side effects tend to last only a few weeks and include · Dental discomfort · TMJ pain and headaches · Salivation · Bruxism No adverse effect on TMJ long-term
