Obstructive Sleep Apnea

what are the 3 types of sleep apnea?

-CSA

-OSA

-mixed sleep apnea

what is central sleep apnea?

-sleep apnea that occurs when the brain doesn’t send appropriate signals to muscles for breathing, leading to no muscular effort of breathing

what type of sleep apnea is characterized by no muscular effort of breathing?

-central

what is obstructive sleep apnea?

-sleep apnea that occurs when the brain sends signals to muscles for appropriate breathing effort, but the airway is obstructed which prevents air flow

what type of sleep apnea is characterized by airway obstruction?

-OSA

what is the pathogenesis of OSA?

-sleeping leads to decreased muscle tone → collapse of airway muscles → complete collapse due to excess weight or tissue → impaired air flow → impaired oxygenation → release of stress hormones → eventual CV stress

why is OSA associated with increased CV risk?

-b/c of continual stress hormone release in response to poor oxygenation

what is snoring?

-nighttime gurgling/noises that occur due to partial airway obstruction

what is the most common cause of OSA in pediatric patients?

-tonsil & adenoid hypertrophy

what are the 3 possible causes of OSA in pediatric patients?

-tonsil & adenoid hypertrophy

-obesity

-allergies (inflammation)

what are the 4 preferred diagnostic studies for identifying pediatric OSA?

-allergy eval

-soft tissue lateral neck x-ray

-sleep study

-laryngoscopy

OSA requires a ______ for diagnosis

-sleep study

OSA can be caused by obstruction at what 3 levels?

-nasal

-oropharyngeal

-tongue

what are 3 common causes of nasal OSA?

-turbinate hypertrophy

-septal deviation

-nasal polyps

what are 3 common causes of oropharyngeal OSA?

-low-lying soft palate

-elongated uvula

-tonsillar hypertrophy

what are 2 common causes of OSA related to the tongue?

-large tongue base (macroglossia)

-enlarged lingual tonsils

what are the 8 common symptoms of OSA?

-daytime fatigue/sleepiness

-morning sluggishness

-h/a

-loud snoring &/or witnessed episodes of apnea

-restlessness & extremity thrashing during sleep

-”brain fog” (cognitive impairment)

-recent weight gain

-impotence

what is the hallmark symptom of OSA?

-daytime fatigue/sleepiness

before diagnosing OSA, what 4 things must be ruled out?

-drug-induced apnea

-seizure d/o

-narcolepsy

-depression

what is the most common patient demographic to present with OSA?

-middle-aged obese males

what is the classification tool for OSA?

-Mallampati classification

what is Mallampati Class I OSA?

-visually open airway + visualized soft palate, uvula, fauces, & tonsillar pillars

what is Mallampati Class II OSA?

-obscured tonsillar pillars + visualized soft palate, uvula, & fauces

what is Mallampati Class III OSA?

-obscured tonsillar pillars & soft palate + visualized uvula

what is Mallampati Class IV OSA?

-no visualization of structures

what are the 2 necessary criteria for an OSA diagnosis?

-Sx of nocturnal breathing disturbances OR daytime sleepiness despite sufficient opportunity for sleep + no other causes

-5+ episodes of obstructive apnea or hypopnea per hr of sleep

if a patient has adequate symptoms of nocturnal breathing disturbances, how many episodes of apnea/hypopnea are required per hour for a diagnosis of OSA?

-5+

OSA can be diagnosed w/o symptoms if a patient has ________ episodes of obstructive apnea or hypopnea/hour of sleep

-15+

what are the 2 screening tools for OSA?

-Epworth Sleepiness Scale

-STOP-BANG Questionnaire

what is the normal point range for the Epworth Sleepiness Scale?

-0-10

what score of the Epworth Sleepiness Scale indicates mild sleepiness?

-11-14

what score of the Epworth Sleepiness Scale indicates moderate sleepiness?

-15-17

what score of the Epworth Sleepiness Scale indicates severe sleepiness?

-18

an Epworth Sleepiness Scale score of _______ indicates that a sleep study should be considered for the patient

> 11

what data points does the STOP-BANG questionnaire assess?

-Snore

-Tired

-Observed

-blood Pressure

-Body mass index

-Age

-Neck circumference

-Gender

what is the preferred diagnostic study for OSA?

-sleep study/polysomnography

what diagnostic study for OSA allows direct documentation of apneic episodes during sleep?

-sleep study

a sleep study for OSA should always be done before what?

-surgery

what are the 2 common cardiac manifestations observed during a sleep study for OSA?

-bradyarrhythmia during apnea

-tachyarrhythmia when breathing again

sleep studies for OSA can be done in what 2 ways?

-in-lab

-at home

a sleep study measures what 6 variables?

-AHI

-eye movements

-O2 sat

-leg movements

-EEG brain waves

-EKG

what is the AHI?

-Apnea/Hypopnea Index

apnea is defined as a pause in breathing for how long?

> 10s

hypopnea is defined as a ______ reduction in airflow

-50%

how is the AHI calculated?

-(apneas + hypopneas)/hrs of sleep

what is the normal AHI?

-0-5

what AHI index is indicative of mild OSA?

-5-15

what AHI index is indicative of moderate AHI?

-15-30

what AHI index is indicative of severe AHI?

> 30

OSA increases the risk of what 6 things?

-HTN

-strokes

-MI

-afib

-CHF

-sudden death

what are the recommended lifestyle modifications for managing OSA (3)?

-weight loss

-avoidance of alcohol

-avoidance of sedatives

what is the 1st line therapeutic method for OSA management?

-PAP

what is the biggest downside of using PAP for OSA management?

-patient noncompliance

when prescribing CPAP for OSA, what is the goal titration?

-minimum pressure required

an OSA’s patient CPAP machine should be ideally set to what pressure?

-minimum needed

how are initial CPAP settings for a patient’s OSA determined?

-based on initial sleep study

what are the 3 components of CPAP settings?

-inspiratory positive airway pressure

-RR

-FiO2

what is the maximum CPAP inspiratory positive airway pressure?

-20cm H2O

what is the typical CPAP inspiratory positive airway pressure?

-5-10cm H2O

what is the typical CPAP RR?

-20bpm

what is the typical CPAP FiO2?

-40-100%

what are the baseline CPAP settings for OSA?

-40% FiO2

-20bpm

-10/5 inspiratory positive airway pressure

when are auto-titrating CPAP devices used?

-for patients with mild OSA
-for patients who are intolerant to standard CPAP

what are alternatives to CPAP for managing OSA?

-oral appliances

-surgical intervention

how are oral appliances used to manage OSA?

-worn in the mouth at bedtime to hold jaw forward & prevent pharyngeal occlusion

what is the downside of using oral appliances to manage OSA?

-poor compliance

when are oral appliances typically used for managing OSA?

-patients who are intolerant to CPAP

oral appliances can only be used for OSA that is associated with obstruction of what level?

-oropharyngeal

what are the 6 surgical intervention options for managing OSA?

-uvulopalatopharyngoplasty

-nasal septoplasty or polypectomy

-maxillomandibular advancement

-genial bone advancement technique

-upper airway stimulator

-tracheostomy

what is a uvulopalatopharyngoplasty?

-resection of pharyngeal soft tissue to amputate 15mm of the free edge of the soft palate & uvula

what is the primary downside of managing OSA with a uvulopalatopharyngoplasty?

-very painful

what 2 surgical interventions can be used to manage OSA caused by nasal obstruction?

-nasal septoplasty

-nasal polypectomy

what is a maxillomandibular advancement?

-permanent surgical repositioning of upper & lower jaw bones using plates & screws to relieve airway obstruction

what is the genial bone advancement technique?

-permanent surgical repositioning of the base of the tongue to pull it forwards & increase airway size

what is an upper airway stimulator?

-outpatient surgical implant that uses leads to stimulate the hypoglossal nerve when taking a breath while sleeping to prevent the tongue from obstructing the airway

what nerve is stimulated using a UAS to prevent airway obstruction?

-hypoglossal

what surgical intervention for OSA management can be performed outpatient?

-UAS

what is the only definitive Tx for OSA?

-tracheostomy

when is a tracheostomy used for managing OSA?

-patient with life-threatening arrhythmia

-patient with severe disability & refractory OSA

what is the absolute last-resort management option for OSA?

-tracheostomy

CSA increases the risk of what 2 conditions? why?

-HF

-afib

-elevated sympathetic NS activity

what is the most common cause of CSA?

-HF

how can opioid use lead to CSA?

-b/c opioids suppress resp effort

what is the hallmark respiratory PE finding of CSA?

-Cheyne-Stokes breathing

what is the Tx for CSA?

-treat underlying cause

-supplemental O2