Obstructive Sleep Apnea Flashcards
Sleep Apnea
Sleep-related interruption in breathing in the presence of respiratory effort
Hypopnea
defined as decreased airflow and drop in saturation of at least 4%
Risk Factors
upper airway narrowing
obesity
alcohol or sedative use
smoking
higher rates with chronic heart and lung disease
Prevealence
more common in males
3-7% of males
2-5% of females
2% of otherwise healthy children
Symptoms
snoring
sleep interruption, sometimes with gasping
nocturia, insomnia, restlessness
witnessed apnea
difficulty concentrating, morning fog, memory problems, work difficulty
hypertension, daytime headaches
sexual dysfunction
What constitutes problematic snoring?
adults - bothersome to partner, loud enough to hear through closed doors
children - more than three times per week
What duration of apnea is considered significant?
10 seconds
How is daytime fatigue commonly described? What is used to measure daytime fatigue?
lack of energy, sometimes difficulty concentrating rather than sleepiness
Epworth Sleepiness Scale is used to measure daytime fatigue; >9 is the cutoff for true sleepiness
STOP-BANG
STOP – Symptoms; BANG – Signs
Snore: Do you Snore loudly (can be heard through closed doors?)
Tired: Are you Tired, fatigued, or sleepy during the day?
Observed: Has anyone Observed that you stop breathing during sleep?
Pressure: Do you have high blood Pressure?
BMI: Body mass index over 35
Age: Age over 50
Neck: Neck circumference >16” female, >17” male
Male?
Scoring: 0-2 = low risk, 3-4 = moderate risk, 5-8 = high risk
Adult Physical Findings
usually nonspecific
obesity
high blood pressure
bulk neck (>16” in females; >17: in males)
narrow airway, enlarged tonsils, high arched hard palate
nasal congestion, or narrow nasal passages
Physical Findings in Children
more often related to post-inflammatory/ anatomic upper airway obstruction; no room in throat to breath
large “kissing” tonsils; lack of air space between tonisls
adenoidal speech
underlying craniofacial abnormalities
obesity is becoming a more common risk factor
Pathophysiology
recurrent, functional collapse of the velopharyngeal or oropharyngeal airway during sleep
airflow is reduced despite breathing efforts
causes intermittent abnormalities in gas exchange (hypoxemia, hypercapnia - high CO2)
When is sleep apnea most likely to occur?
can occur during any phase of sleep, but is most likely during REM sleep because of decreased tone in the genioglossus muscle, which increases upper airway obstruction
What position is sleep apnea most likely to occur?
supine position; decreased muscle tone causes tongue to fall back and occlude the airway
Adverse Outcomes in Adults
2-3 X increase in all-cause mortality, especially cardiac arrhythmias, coronary artery disease, stroke, heart failure, systemic and pulmonary hypertension
Motor vehicle crashes are 2-3 X more frequent in people with OSA than without
Inattention resulting from daytime fatigue can cause work/school difficulty
Increased risk for metabolic problems such as DM2, metabolic syndrome, polycystic ovarian syndrome, fatty liver disease; Increased risk for metabolic problems is greater than would be expected based on obesity alone
Adverse Outcomes in Children
Inattention and behavioral problems
Trouble keeping up with school and activities
If severe, growth failure and failure to thrive
If severe, systemic hypertension, right or left ventricular dysfunction, cor pulmonale
Adverse Perioperative Problems
Increased risk of: Respiratory failure, Postoperative oxygen desaturation, Cardiac arrhythmias, ICU transfer, Longer PACU and/or hospital stay
Mechanisms are related to anesthesia and other medications, which mimic sleep; supine positioning; sleep deprivation; inability to use CPAP
This is why many facilities now require screening for OSA as part of the pre-operative evaluation process. Enables more proactive planning, scheduling.
Differential Diagnosis Adults
Loud Snoring without OSA
Central Sleep Apnea
Other Sleep Disorders
Sleep difficulty related to stress, depression, etc.
Other causes of abrupt awakening - aspiration nocturnal panic attacks
other causes of persistent fatigue (anemia, thyroid disease, etc.)
Differential Diagnosis Children
habitual snoring without apnea
central sleep apnea
other sleep disorders which cause frequent arousals
other causes of inattentive or disruptive behavior
Diagnosis Adults
polysomnography (sleep study)
suggested by history (STOP-BANG, Epworth Sleepiness Scale)
may find abnormal airway
labs to rule out other causes - not diagnostic
home sleep tests - less sensitive; more for ruling out sleep apnea
Diagnosis Children
more frequently diagnosed using history and exam findings: • otherwise healthy child with adenotonsillar hypertrophy, snoring, observed apneas, daytime fatigue, no other abnormalities or complicating factors
polysomnography recommended if there are other problems: obesity, congenital abnormalities or problems
labs to rule out other problems (metabolic or steroid
Polysomnography
Sleep Study
obstructive sleep apnea diagnosed if there are 5 events (apnea, hypopnea, desaturation) per hour in a patient with typical symptoms; or in patients with 15 events per hour regardless of symptoms
Most Effective Treatment Adults
CPAP
10-20% loss in body weight
Other Treatments Adults
surgery (uvuloplasty or septoplasty)
oral appliances - reposition jaw
treatment of nasal congestion - saline flushes, nasal steroid sprays, breath-right strips
Treatment Children
more likely to be treated with surgery
CPAP if no surgical option
Lifestyle interventions: healthy diet, exercise, weight management
management of allergy/nasal congestion
orthodontia