Sleep-Related Breathing disorders - Clin Med 3

What does this refer to

• With EEG and Esophageal Manometry

• SpO2

• Respiratory rate and effort

  • Gas exchange

• Heart rate

• Eye and leg movements

• Muscle electrical activity

• Body position

Polysomnography assessment

What does a BMI of < 18.5 indicate

Underweight

What does a BMI of 18.5-24.9 refer to

Healthy weight

What does a BMI of 25.0-29.9 indicate

overweight

What does this BMI refer to > or equal to 30

obese

What is the first box

FEV1/FVC

What is the second box

FEV1

What is the third box

FVC

What is the 4th box

PEFR

What is the 5th box

MW

What is the 6th box

TLC

What does this refer to

• A 56-year-old man presents to your office for excessive fatigue.

• He complains of falling asleep all the time at work, which is “very distressing" as it has been affecting his work.

• He denies sudden loss of muscle tone or hallucinations before or after falling asleep.

• His wife reports that he snores at night.

• A physical examination demonstrates an obese, lethargic man with unremarkable findings.

Sleep apnea

What does this refer to

• A serious, common, underdiagnosed sleep disorder that is characterized by disordered breathing resulting in numerous hypoxic episodes throughout sleep preventing the patient from restorative sleep

• Two specific etiologies

  • Obstructive sleep apnea (OSA)

  • Central sleep apnea

Sleep Apnea

What classification of severity of sleep apnea is below

• AHI > 30 (more than 30 episodes per hour)

Severe obstructive sleep apnea

What classification of severity of sleep apnea is below

• AHI 15-30

Moderate obstructive sleep apnea

What classification of severity of sleep apnea is below

• AHI 5-15

Mild obstructive sleep apnea

What does this refer to

• M > F

• MC obese and middle-aged patients

• Risk ↑ with obesity, hypothyroidism and tobacco use

• Exacerbated by EtOH, sleep medications, or illnesses causing nasal obstruction

• Affects > 936 million people worldwide

• > 80% are undiagnosed

Epidemiology of Sleep Apnea

What does this refer to

• Obstructive sleep apnea (OSA)

  • Anatomical

  • Characterized by obstructive apneas, hypopneas, and/or respiratory effort-related arousals (RERAs)

    • Repetitive complete or partial collapse of the upper airway during sleep

• Central sleep apnea (CAS)

  • Neurological

  • Can be caused by heart failure, stroke, high altitude sleeping

Etiology of Sleep Apnea

What does this refer to

Clinical history of sleep apnea

What does this refer to

• No abnormal findings

• What to assess

  • Oropharyngeal crowding

    • Enlarged tonsils

    • Excessive soft tissue

    • Enlarged uvula or tongue

  • Nasal septum deviation

  • Short neck

Physical exam of sleep apnea

What does this refer to

• Narcolepsy

  • distinguishing factor

    • clinical features such as cataplexy, hypnagogic hallucinations, sleep attacks, and sleep paralysis

  • can be differentiated on polysomnography

• Respiratory disease (e.g., chronic obstructive lung disease)

  • distinguishing factor

  • positive medical history and polysomnography results

Differential diagnosis sleep apnea

What does this refer to

Workup for Sleep Apnea

What does this refer to

Polysomnography with Apnea-Hypoxia Index (AHI)

• 15 obstructive apneas/hour

• 5 apneas/hr and snoring/breathing pauses with daytime somnolence

The gold standard and diagnostic study for sleep apnea

What does this refer to

• Weight loss

  • Weight loss medications

  • Exercise

  • Severely obese & failure of conservative treatment

    • Weight loss surgery

• Surgical intervention (non-responders)

  • Uvulopalatopharyngoplasty (UPPP)

  • Nasal septoplasty

  • Tracheostomy

• Continuous positive airway pressure (CPAP)

Clinical interventionSleep Apnea

What does this refer to

Clinical managementSleep Apnea

What does this refer to

• Weight loss and exercise

• Low fat, low sodium, low sugar, low carb diet

• Meals

  • Eat smaller meals more frequently instead of 3 larger meals daily

Complementary and alternative managementSleep Apnea

What does this refer to

Morbidity/mortality/ComplicationsSleep Apnea

What is the left box

Central sleep apnea (CSA)

What is the right box

Obstructive sleep apnea (OSA)

What does this refer to

• Poor breathing in some people with obesity

• Inefficient respiration —> ↓ O2 and ↓ CO2 levels in the blood

• Also known as Pickwickian syndrome

Obesity Hypoventilation Syndrome

What does this refer to

• MC in obese patients

Epidemiology Obesity Hypoventilation Synfrome

What does this refer to

• Exact cause unknown

• Hypothesis

  • Excess weight against chest wall makes it more difficult to deep breathe and quickly enough

    • Results in defect in the brain’s control over breathing

• Results in acidemia

  • If in a stable condition kidneys have enough time to correct acidemia

• What is the expected ABG in the unstable patient

  • pH ↓ (acidotic, usually < 7.35)

  • CO2 ↑

  • HCO3 ↓

• What is the expected ABG in the stable patient

  • pH: 7.35-7.45

  • CO2: 35-45

  • HCO3: 22-26

EtiologyObesity Hypoventilation Syndrome

What does this refer to

• Main sx due to lack of sleep

  • Poor sleep quality

  • Daytime sleepiness

  • Depression

  • Headaches

  • Fatigue

• Chronic hypoxia with elevated CO2

  • SOB/DOE

  • Chronic fatigue/fatigue with minimal activity

Clinical HistoryObesity Hypoventilation Syndrome

What does this refer to

• BMI > or equal to 30kg/m2

• Cyanosis

  • Lips

  • Fingers/toes

  • Skin

• SaO2 ↓

• R side HF (HF due to a respiratory problem —> cor pulmonale)

  • Sx

    • Edema

    • SOB/DOE

    • Fatigue with minimal activity

Physical examObesity Hypoventilation Syndrome

What is a ddx for obesity hypoventilation syndrome

Sleep apnea

What does this refer to

WorkupObesity Hypoventilation Syndrome

What does this refer to

Workup – best initial test/how’s it diagnosed?Obesity Hypoventilation Syndrome

What does this refer to

• Weight loss and exercise

• CPAP or BiPAP

• Supplemental O2

• Tracheostomy for severe cases

• Interventions can be initiated (and/or changed) inpatient or outpatient

• Weight loss can reverse OHS

Clinical interventionObesity Hypoventilation Syndrome

What does this refer to

• Weight loss drugs

  • GLP-1

Clinical pharmacotherapeuticsObesity Hypoventilation Syndrome

What does this refer to

• Weight loss diet

• Exercise

Complementary and alternative managementObesity Hypoventilation Syndrome

What does this refer to

Morbidity/mortalityObesity Hypoventilation Syndrome

What does this refer to

• May lead to heart/blood vessel problems, severe disability, or death

• Complications

  • Depression, agitation, irritability

  • Increased risk for accident/mistakes if able to work

  • Intimacy/sex problems

• Cardiac complications

  • HTN

  • Cor pulmonale

  • Pulmonary HTN

Prognosis/complicationsObesity Hypoventilation Syndrome

What does this refer to

• Rare disorder

• Similar to OSA but doesn’t meet the criteria (not as severe)

• May be classified between snoring and sleep apnea

Upper Airway Resistance Syndrome (UARS)

What does this refer to

• Typically of average weight

EpidemiologyUpper Airway Resistance Syndrome (UARS)

What does this refer to

• Often caused by partial narrowing in the retropalatal and retroglossal areas of the airway

  • Soft tissue relaxation not allowing for proper airflow during sleep

  • Tongue falling back

• Leads to frequent respiratory-related arousals from sleep (RERAs)

EtiologyUpper Airway Resistance Syndrome (UARS)

What does this refer to

• Non-refreshing sleep

• Snoring

• Excessive daytime sleepiness

• Unexplained daytime tiredness

• Difficulty initiating or maintaining sleep (insomnia

• Heavy breathing during inhalation

• Morning HA

Clinical HistoryUpper Airway Resistance Syndrome (UARS)

What does this refer to

• Linked to significant cognitive and behavioral problems in children

  • Learning disabilities

  • ADD +/- hyperactivity

  • Aggression

Clinical HistoryUpper Airway Resistance Syndrome (UARS)

What does this refer to

• No acute findings

• BMI

  • Healthy (not overweight) 18.5-24.9

• If UARS complications

  • HTN

Physical examUpper Airway Resistance Syndrome (UARS)

What does this refer to

• OSA v CSA

• OHS

• Often misdiagnosed as

  • Idiopathic insomnia

  • Idiopathic hypersomnia

  • Chronic fatigue syndrome

  • Fibromyalgia

  • ADD +/- hyperactivity

  • Depression

Differential diagnosisUpper Airway Resistance Syndrome (UARS)

What does this refer to

WorkupUpper Airway Resistance Syndrome (UARS)

What does this refer to

Workup – best initial test/how’s it diagnosed?Upper Airway Resistance Syndrome (UARS)

What does this refer to

• Avoid EtOH and sedative medications

• Optimal sleep position

• Weight loss if “overweight”

• CPAP

• Oral appliances

  • Mandibular advancement splint (MAS)

• Surgery to enlarge the airway

Clinical interventionUpper Airway Resistance Syndrome (UARS)

What is the clinical pharmacotheapeutics upper airway resistance syndrome (UARS)

None

What does this refer to

• Healthy diet and exercise to maintain optimal BMI

Complementary and alternative managementUpper Airway Resistance Syndrome (UARS)

What does this refer to

Morbidity/mortalityUpper Airway Resistance Syndrome (UARS)

What does this refer to

• Treatment compliance improves symptoms and quality of life

• May progress to sleep apnea if untreated/non-compliance

Prognosis/complicationsUpper Airway Resistance Syndrome (UARS)

What does this refer to

• = RV + ERV + TV + IRV. Total amount of air the lung can hold

Total Lung Capacity (TLC)

What does this refer to

• The maximal amount of air that can be exhaled as fast as possible after a maximal inhalation. The result of this test is then compared to a predicted normal based on age, height, and weight, ethnic origin & smoking history

Forced Vital Capacity (FVC)

What does this refer to

• the amount of volume of air that has been exhaled at the end of the 1st second of forced expiration

Forced Expiratory Volume in 1 second (FEV1)

If BOTH the FVC and the FEV1 are less than 80%

predicted there is a restrictive disease present. FEV1 is also used to determine the severity of disease – more on that later.

Step 1 of Determining Restrictive Disease

FEV1/FVC result (<80% of predicted → OBSTRUCTIVE)

Step 2 of Determining Restrictive Disease

If FEV1/FVC is > 80%, look at FVC and FEV1 results individually. If both < 80% → RESTRICTIVE

Step 3 of Determining Restrictive Disease

FEV1/FVC and FVC are both decreased below 80% → MIXED defect