Week 6: Obstructive Sleep Apnea (OSA) Upper Respiratory Disorder Flashcards
Epidemiology
- occurs during sleep
- upper airway is obstructed causing a narrowing of one of more sites of the upper airway, resulting in intermittent breathing patterns
Pathophysiology
- occurs during sleep as the upper airways narrow or collapse, increasing resistance to airflow; causing intermittent breathing patterns
- airflow blocked to lungs
- periods of apnea
What Happens during OSA
-with the onset of sleep, the body muscle tone relaxes, which includes the muscles of the upper airway
>With OSA, the normal work of breathing is unable to overcome the increased resistance in the upper airway, causing airway collapse.
>narrowing of the upper airways increases inspiratory pressure and intrathoracic pressure, resulting in decreased ventilation and gas exchange
-periods of apnea; no gas exchange occurs in alveoli
What occurs as a result of decreased tidal volume and apnea?
- hypoxemia (decreased concentration of O2 in the blood)
- Hypercapnia (increased concentration of CO2 in the blood)
- acidosis
- increased sympathetic vasoconstrictive activity
Clinical Manifestations
- loud snoring
- snorting
- witnessed apnea
- gasping during sleep
- recurrent waking during sleep
- choking
What Diagnoses the presence of OSA?
15 or more obstructive sleep events per hour
What do patients complain about because of these frequent sleep disturbances?
- excessive daytime sleepiness
- falling asleep during quiet times
- short and repetitive attention lapses
- taking intentional naps
Diagnostic Procedures
- begins with sleep history; sleep patterns, history of snoring and daytime sleepiness
- polysomnography (a sleep study)
Diagnostic Procedures: Polysomnography
a sleep study
- biophysical measurements are obtained; electrocardiogram, pulse oximetry, respiratory airflow, eye and skeletal muscle movement, and an electroencephalogram
- apnea-hypopnea index value, number of apneic events per hour, is key value
Treatment Procedures
- CPAP
- weight management
- using pillows for a non-supine position
- oral appliances
- surgical management for primary or secondary interventions
Treatment: CPAP
- treatment of choice
- weight management and loss is the first line intervention in conjunction with CPAP
- continuous positive airway pressure prevents collapse of the upper airway through the use of nasal, oral, or oronasal mask during sleep
- CPAP machine delivers a continuous stream of positive pressure, keeping the airway open and providing an unobstructive airway
Treatments: Surgical Management
-Primary: for patients with severe obstructing anatomy that surgery can correct
-Secondary: patients who are intolerant of CPAP or oral appliances
>tonsillectomy and/ or adenoidectomy, uvulopalatopharyngoplasty, septoplasty, nasal polypectomy, tongue reduction, and epiglottoplasty
>these procedures remove excess tissue in the airway that interferes with maintaining adequate airflow
>bariatric surgery to consider weight reduction is also a consideration
Complications
- mediator of cardiovascular disease because of recurrent hypoxemia
- severe nocturnal hypoxemia can result in cardiac ischemia, myocardial infarction, erectile dysfunction, stroke, atrial fibrillation, heart failure, and sudden cardiac death
Risk Factors
- history of A-fib, nocturnal dysrhythmias, type 2 diabetes, heart failure, pulmonary hypertension
- others: gender(mostly men), obesity, craniofacial or upper airway soft tissue abnormalities, and menopause
Treatment: Oral Appliances
- custom-made to the patient; may be used to maintain airway patency
- assist with mandibular repositioning to hold the mandible in a forward position to keep the airway open
- positioning of the tongue is accomplished with tongue-retaining devices
