2. Roecker - Sleep Apnea Flashcards
What defines hypopneas?
Events at least 10 second long where ventilation is reduced 50% or more from baseline despite continued breathing.
How many obstructive sleep events are needed for a diagnosis by OSAHS?
At least 5 obstructed breathing events and excessive daytime sleepiness
What is supported by AASM?
OSAHS in pts with 15 or more obstructed breathing events per hour in patients w/o symptoms
What is the main OSAHS mechanism?
Airway is sucked closed during inspiration
What are 4 factors contributing to OSAHS mechanism?
Muscle tone fails and airway narrows
Dilating muscles relax during sleep and fail to oppose negative pressure
Snoring may preempt air occlusion
Patient will untimely wake (but the brain doesn’t wake)
What are 3 disposing factors of OSAHS?
Obesity - seen in 50% of patients
Shortening of the mandible and/or maxilla
Hypothyroidism and acromegaly
Who is the common pt for OSAHS?
Most common in middle age men
What is the hallmark symptom of OSAHS?
Daytime sleepiness, may present like narcolepsy
What are four other clinical symptoms of OSAHS?
Loud snoring
Witnessed breathing interruptions
Awakenings due to GPA spring or chocking
Depression
What are OSAHS symptoms a result of?
Physiologic mechanism
Ex. Changes in intrathroacic pressures
What are some high risk conditions?
Obesity, heart failure, uncontrolled HTN, type 2 DM, etc.
What are 4 preliminary questions for screening?
Daytime sleepiness?
Snoring?
Presence of high risk factors?
STOP-BANG?
What is STOP in the STOP-BANG acronym? What is its purpose?
S = snore loudly? T = tired during the day? O = observed stop breathing? P = high blood pressure? Purpose is for the questions to ask
What is BANG in the STOP-BANG acronym? What is its purpose?
B = body mass index (>35) A = age (>50) N = neck circumference (>40cm) G = gender (male) Objective measures (and predisposing factors)
How it STOP-BANG evaluated?
3 or more questions indicates a high OSA risk
3 or more questions + symptoms = 84% accurate diagnosis
5 or more = severe sleep apnea
What is the apnea-hypopnea index?
Number of Aeneas dead hypopneas per hour of sleep
Diagnosed = 5/hour
What is the oxygen desaturation index?
Frequency >3-4 oxyhemoglobin desaturations per hour of sleep
What is the Epworth Sleepiness Scale?
Scores 8 activities and their potential to put the patient to sleep on a scale of 0 (unlikely) to 3 (very likely)
What is included in objecting testing?
In-lab polysomnography
Home testing with portable monitors
What is included in In-Labratory polysomnography? What is its purpose?
Watches the pt sleep and measure different readings on the pt. Confirmation of diagnosis w/ appropriate numbers of obstructive events in combo w/ symptoms
What are some features of home testing?
Limited study because it has no EEG or EKG data
Not to be used as a standard in pts w/ major comorbidities
Reads airflow, respiratory effort, and oxygenation
What are the 4 treatments of sleep apnea?
- Positive airway pressure
- Behavior modifications
- Oral appliances
- Surgery
What is positive airway pressure? Where is its place in treatment of sleep apnea?
This is the treatment of choice!
Modified pressure to keep airway patent during inspiration
Applied though nasal, oral, or oronasal masks
Shown to benefit most OSAHS symptoms
What is behavior modifications place in therapy of sleep apnea?
Should not be the only course of treatment
- combination weight loss to BMI 25 or less and PAP machine can increase effectiveness
- sleep positioning (using a positioning device), but will need to be evaluated to see if other options are more useful
