OSA

Sleep-related breathing disorders are characterized by abnormal breathing patterns during
sleep and include
◦ Obstructive sleep apnea syndrome
◦ Central sleep apnea syndrome
◦ Mixed sleep apnea
◦ Sleep-related hypoventilation/hypoxemia syndromes
◦ According to the AASM, sleep disorders can be classified into eight major groups (you will
not be tested on all 8 groups)

Respiratory Therapists can specialize in sleep medicine and obtain a specialty credential
◦ CRT-SDS
◦ RRT-SDS
◦ Benefits
◦ Consistent schedule
◦ Typically, no/minimal weekends or holidays
◦ Work relatively independent overnight

OSA is a common sleep disorder that often requires lifelong
care
◦ Cardinal features include:
◦ Obstructive apneas (collapse of upper airway)
◦ Hypopneas (shallow and slower breathing)
◦ Respiratory effort–related arousals (RERAs)
◦ Caused by recurring collapse of the upper airway during sleep , increased respiratory
effort for 10 sec. or more leading to an arousal from sleep but not a full apnea

CSA is a disorder characterized by:
◦ The repetitive stopping or reduction of both air flow and ventilatory effort during sleep
◦ Central comes from the brain forgetting to send signals to breathe

Both Obstructive & Central events are occurring

SRHHSs include a broad range of sleep disorders
◦ Some are quite common
◦ Obesity hypoventilation syndrome
◦ Co-existing with COPD, the so-called “Overlap Syndrome”
◦ Others are rare
◦ Congenital central hypoventilation syndrome
◦ Neuromuscular and chest wall disorders

Apnea is defined as the cessation of airflow—a complete obstruction for at least 10 seconds—
with a simultaneous 3% to 4% decrease in the patient’s SaO2.
◦ Hypopnea is defined as a reduction of airflow between 30% and 50%—with an associated
drop in the patient’s SaO2.

AHI is generated from In lab PSG (polysomnogram)
◦ The AHI score provides the following three severity categories of sleep apnea:
◦ Mild—5 to 15 apnea-hypopnea episodes per hour
◦ Moderate—15 to 30 apnea-hypopnea episodes per hour
◦ Severe—greater than 30 apnea-hypopnea episodes per hour
◦ NORMAL IS LESS THAN 5 EPISODES PER HOUR
◦ RDI is generated from an HST (home sleep test)
◦ Calculated off total rest time (not sleep time), however patient may not be asleep for quite
some time after giving a lower RDI than anticipated
◦ RDI will take REI (respiratory event index) into account

Two major sleep stages during normal sleep
◦ Non–rapid eye movement (non-REM) sleep
◦ Quiet or slow-wave sleep
◦ Rapid eye movement (REM) sleep
◦ Active or dreaming sleep
◦ Why do we care about sleep cycles?
◦ REM is DEEP Sleep, when deep sleep is entered apneas & hypopneas often increase
◦ Rem is also the “refreshing” sleep

Assessment Tools Used in the Office
◦ The Epworth Sleepiness scale
◦ The Fatigue Severity Scale (FSS) /The Visual Analogue Fatigue Scale (VAFS)
◦ The Mallampati classification score

PFT
◦ Flow Volume loop may alert evaluator of airway anomaly & or upper airway obstruction
◦ Enlarged Uvula, enlarged tonsils, long soft palate, redundant lateral pharyngeal walls, macroglossia
◦ ABG
Severe Sleep Apnea ABG
Chronic Ventilatory Failure with Hypoxemia

Diagnosis
◦ Begins with a comprehensive sleep evaluation, which includes:
◦ A history from the patient and/or the patient’s bed partner
◦ Especially noting the presence of:
◦ Snoring
◦ Sleep fragmentation
◦ Periods of apnea during sleep
◦ Non-refreshing sleep
◦ Persistent daytime sleepiness

Testing
◦ The diagnosis and type of sleep apnea is confirmed by one of the following methods:
◦ In-home portable monitoring (Known as HST)
◦ Patient is instructed on use and sets up the equipment for monitoring at home when moderate
or severe OSA is suspected
◦ Much debate with this method
◦ Polysomnography (PSG)
◦ A specialized sleep test that monitors and records several physiologic parameters that occur during
sleep
◦ May be administered as either:
◦ A full-night, attended, in-laboratory polysomnography
◦ A split-night, attended, in-laboratory polysomnography

Diagnosis for Central Sleep Apnea
◦ Diagnosed when most of the respiratory events are central apneas or hypopneas from the Sleep Study
◦ An absence of nasal or oral air flow and thoracoabdominal movements
◦ Patients diagnosed with CSA are evaluated carefully for:
◦ The presence of cardiac disease
◦ Lesions involving the cerebral cortex and the brain stem

General Management Of Sleep Apnea
◦ The patient should be educated about the risk factors, natural
history, and long-term consequences of OSA
◦ Patient warned about the potential danger and consequences of driving an automobile or operating other equipment or
tools while sleepy
◦ The types of therapy for OSA include:
◦ Behavior modification
◦ Weight loss (if overweight), exercise, changing sleep positions (OSA Worse in Supine Position), Abstaining from alcohol, avoi d
certain medications
◦ Positive airway pressure therapy (most common)
◦ Oral appliances
◦ Surgery
◦ Implantable upper-airway stimulator

Treatment
◦ CPAP
◦ Continuous positive airway pressure
◦ APAP
◦ Auto positive airway pressure
◦ BiPAP
◦ 2 levels of support
◦ Bipap with back up rate
◦ 2 levels of support with a respiratory rate bult in

Treatment Adherence
◦ It is estimated that between 30-80% of sleep apnea patients are nonadherent to CPAP therapy.
Nonadherence is defined as a mean of less than or equal to 4 hours of use per night.
◦ What can we do to help?
◦ EDUCATE!!
◦ Mask
◦ Cleaning
◦ Upkeep of supplies
◦ Tracking of usage

STOP BANG acronym
snoring, tiredness, observed stopped breathing, pressure(highbp), BMI, age, neck size, gender is male