Sleep-Disordered Breathing — MCQs

10 questions

The most appropriate immediate management of prolonged Scoline apnea is

A 56-year-old woman with diabetes, hypertension, and hyperlipidemia is found to have an A1C of 11 despite her best attempts at diet and faithfully taking her metformin and glyburide. She reports severe fatigue and sleepiness in the daytime, which has limited her ability to exercise. On examination, she is obese, has a full appearing posterior pharynx, clear lungs, a normal heart examination, and trace bilateral edema. Her TSH is 2.0 m/L (normal). Before adding another oral agent or switching to insulin, what is the best next step?

A 40-year-old man presents with daytime sleepiness and impaired concentration and memory. On examination his BMI is 41 kg/m2, BP is 160/100 mm Hg. His awake ABG analysis is given: PaO2=66 mm Hg, PaCO2=50 mm Hg, HCO3=28 mEq/L. What is the most likely diagnosis?

What is the minimum diagnostic threshold for obstructive sleep apnoea according to current guidelines?

Long-standing obstruction due to enlarged tonsils and adenoids can cause:

During polysomnography, which stage of sleep is represented by the marked areas when observing the following wave patterns? EOG (Electrooculography) EEG (Electroencephalography) EMG (Electromyography)

What is a likely diagnosis for a patient with persistent fever after treatment for pneumonia?

A 45-year-old male presents to the emergency department following a motor vehicle accident. He complains of severe chest pain and difficulty breathing. On examination, he appears distressed, with a respiratory rate of 28 breaths per minute. His oxygen saturation is 88% on room air. There is visible bruising on the chest, X-ray is done which is shown below. Which of the following is seen in this patient?

Consider the following statements: The clinical features of tension pneumothorax include 1. tracheal shift to contralateral side 2. absent breath sounds on the affected side 3. low output circulatory failure 4. peripheral cyanosis Which of the statements given above is/are correct?

Q10

All of the following criteria are required for diagnosis of obesity hypoventilation syndrome except -

Sleep-Disordered Breathing Indian Medical PG Practice Questions and MCQs

Question 1: The most appropriate immediate management of prolonged Scoline apnea is

A. Reversal with neostigmine
B. Estimation of plasma cholinesterase
C. Exchange transfusion
D. Continuation of artificial ventilation (Correct Answer)

Explanation: ***Continuation of artificial ventilation*** - **Scoline (succinylcholine)** apnea is often due to a deficiency in **pseudocholinesterase (plasma cholinesterase)**, leading to prolonged paralysis. - The most appropriate immediate management is to bridge the period of paralysis with **artificial ventilation** until the drug is metabolized, supporting the patient's respiratory function. *Reversal with neostigmine* - **Neostigmine** is an acetylcholinesterase inhibitor used to reverse the effects of **non-depolarizing neuromuscular blockers**, not depolarizing ones like succinylcholine. - Using neostigmine in scoline apnea would worsen the block by inhibiting the breakdown of acetylcholine at the neuromuscular junction, potentially intensifying the paralysis. *Estimation of plasma cholinesterase* - While **estimation of plasma cholinesterase** can help diagnose the cause of prolonged scoline apnea, it is a diagnostic step, not an immediate management strategy. - The results are not immediate and will not help in the acute respiratory crisis presented by prolonged apnea. *Exchange transfusion* - **Exchange transfusion** is an extreme and invasive measure that is not indicated for managing prolonged scoline apnea. - It carries significant risks and is reserved for conditions like severe hyperbilirubinemia or certain poisonings, not for pseudocholinesterase deficiency.

Question 2: A 56-year-old woman with diabetes, hypertension, and hyperlipidemia is found to have an A1C of 11 despite her best attempts at diet and faithfully taking her metformin and glyburide. She reports severe fatigue and sleepiness in the daytime, which has limited her ability to exercise. On examination, she is obese, has a full appearing posterior pharynx, clear lungs, a normal heart examination, and trace bilateral edema. Her TSH is 2.0 m/L (normal). Before adding another oral agent or switching to insulin, what is the best next step?

A. Arrange for a sleep study to check the patient for obstructive sleep apnea. (Correct Answer)
B. Consider prescribing a sleep aid to help her sleep better and increase her energy to exercise during the day.
C. Assess for possible depression as a contributor to her fatigue.
D. Educate the patient on sleep hygiene as a supportive measure to improve her overall well-being.

Explanation: A 56-year-old woman with diabetes, hypertension, and hyperlipidemia is found to have an A1C of 11 despite her best attempts at diet and faithfully taking her metformin and glyburide. She reports severe fatigue and sleepiness in the daytime, which has limited her ability to exercise. On examination, she is obese, has a full appearing posterior pharynx, clear lungs, a normal heart examination, and trace bilateral edema. Her TSH is 2.0 m/L (normal). Before adding another oral agent or switching to insulin, what is the best next step? ***Arrange for a sleep study to check the patient for obstructive sleep apnea.*** - The patient's presentation with **severe fatigue**, **daytime sleepiness**, **obesity**, and a **full-appearing posterior pharynx** are highly suggestive of **obstructive sleep apnea (OSA)** [1]. - OSA can lead to **insulin resistance** and worsen glycemic control, making it a critical factor to address before escalating diabetes medications. *Consider prescribing a sleep aid to help her sleep better and increase her energy to exercise during the day.* - Prescribing a sleep aid without investigating the cause of her sleep disturbances could mask a serious underlying condition like **OSA**, which requires specific treatment [1]. - While improved sleep might transiently boost energy, it would not address the **pathophysiology of OSA** or its impact on diabetes. *Assess for possible depression as a contributor to her fatigue.* - While **depression** can cause fatigue and impact exercise, her physical findings (obesity, full pharynx) and the specific symptom of **daytime sleepiness** point more strongly towards a primary sleep disorder like OSA [1]. - A definitive diagnosis of OSA would better explain the combination of her symptoms and poor glycemic control. *Educate the patient on sleep hygiene as a supportive measure to improve her overall well-being.* - **Sleep hygiene** is important for overall health, but it is unlikely to resolve severe daytime sleepiness and fatigue caused by a mechanical obstruction like in **OSA** [1]. - This intervention would be insufficient to address the potential link between her sleep disorder and uncontrolled diabetes.

Question 3: A 40-year-old man presents with daytime sleepiness and impaired concentration and memory. On examination his BMI is 41 kg/m2, BP is 160/100 mm Hg. His awake ABG analysis is given: PaO2=66 mm Hg, PaCO2=50 mm Hg, HCO3=28 mEq/L. What is the most likely diagnosis?

A. Obstructive sleep apnea (Correct Answer)
B. Narcolepsy
C. Obesity hypoventilation syndrome
D. Central sleep apnea

Explanation: ***Obstructive Sleep Apnea (Correct Answer)*** - Classic triad: **morbid obesity (BMI 41 kg/m²)**, **excessive daytime somnolence**, and **systemic hypertension (160/100 mmHg)** — hallmarks of OSA - **ABG findings** (PaO2=66 mmHg, PaCO2=50 mmHg, HCO3=28 mEq/L) indicate **chronic nocturnal hypoxemia and hypercapnia** with compensatory **metabolic alkalosis** from repeated apneic episodes - **Cognitive impairment** (impaired concentration and memory) results from **sleep fragmentation** and intermittent nocturnal hypoxia - Obesity promotes **pharyngeal fat deposition** → upper airway narrowing and collapse during sleep → recurrent obstructive events *Narcolepsy* - Causes excessive daytime sleepiness but is **not associated with obesity, hypertension, or ABG abnormalities** - Hallmarks include **cataplexy**, sleep paralysis, and hypnagogic/hypnopompic hallucinations — none present here - Caused by **orexin (hypocretin) deficiency**; associated with **HLA-DQB1*06:02**; ABG is normal *Obesity Hypoventilation Syndrome (OHS / Pickwickian Syndrome)* - Defined as **awake PaCO2 >45 mmHg + BMI >30 kg/m²** with exclusion of other causes of hypoventilation - OHS frequently coexists as an **overlap with and consequence of severe OSA** rather than being the primary diagnosis - In this setting, **OSA is the most prevalent and primary diagnosis**; OHS is specifically considered when awake hypoventilation persists despite adequate OSA treatment *Central Sleep Apnea* - Results from **failure of central respiratory drive** (brainstem), not upper airway obstruction - Associated with **congestive heart failure, opioid use, high-altitude exposure, or neurological disease** — none present here - Not characteristically associated with morbid obesity; clinical and ABG picture here favors an **obstructive** rather than central pattern

Question 4: What is the minimum diagnostic threshold for obstructive sleep apnoea according to current guidelines?

A. AHI <5 events per hour
B. AHI 15-30 events per hour
C. AHI >30 events per hour (Correct Answer)
D. AHI 5-15 events per hour

Explanation: AHI >30 events per hour - An Apnoea-Hypopnoea Index (AHI) greater than 30 events per hour indicates severe obstructive sleep apnea (OSA), which is definitively above the minimum diagnostic threshold [1]. - While an AHI of 5 or more is generally considered diagnostic for OSA, an AHI >30 signifies severe disease and often leads to more pronounced symptoms and health risks [1]. *AHI <5 events per hour* - An AHI score of less than 5 events per hour is typically considered normal or within the non-pathological range for sleep-disordered breathing [1]. - Individuals with an AHI below this threshold usually do not meet the diagnostic criteria for any form of sleep apnea. *AHI 15-30 events per hour* - This range indicates moderate obstructive sleep apnea. While it is diagnostic for OSA, it is not the minimum threshold [1]. - Patients in this category often experience significant symptoms and may require treatment, but it is not the lowest AHI at which a diagnosis can be made. *AHI 5-15 events per hour* - This AHI range is considered mild obstructive sleep apnea. An AHI of 5 or more, accompanied by relevant symptoms, is generally the minimum diagnostic threshold for OSA [1]. - However, the question asks for the minimum diagnostic threshold, and while 5 events per hour is a minimum, "AHI >30 events per hour" indicates a clear and severe diagnostic case.

Question 5: Long-standing obstruction due to enlarged tonsils and adenoids can cause:

A. Obstructive sleep apnea (Correct Answer)
B. Pulmonary embolism
C. Chronic hypoxemia
D. Cor pulmonale

Explanation: Obstructive sleep apnea [1] - Enlarged tonsils and adenoids are a common cause of **upper airway obstruction** during sleep in children and, less commonly, adults. - This obstruction leads to **recurrent episodes of apnea and hypopnea**, characteristic of obstructive sleep apnea [1]. *Pulmonary embolism* - A pulmonary embolism is typically caused by a **blood clot** that travels to the lungs, often originating from deep vein thrombosis. - There is no direct causal link between enlarged tonsils/adenoids and the formation of a pulmonary embolus. *Chronic hypoxemia* - While **obstructive sleep apnea can lead to intermittent hypoxemia**, long-standing obstruction from tonsils and adenoids is not the primary cause of chronic, persistent hypoxemia as an isolated issue. - Chronic hypoxemia typically results from conditions like **severe lung disease (e.g., COPD, cystic fibrosis)** or significant cardiac shunts [2]. *Cor pulmonale* - **Cor pulmonale** (right-sided heart failure) can develop as a *secondary complication* of long-standing, severe obstructive sleep apnea due to chronic hypoxemia and pulmonary hypertension [3]. - However, it is not a direct result of the obstruction itself, but rather a late-stage complication of the resulting physiological changes, and **obstructive sleep apnea** is the more immediate and direct consequence.

Question 6: During polysomnography, which stage of sleep is represented by the marked areas when observing the following wave patterns? EOG (Electrooculography) EEG (Electroencephalography) EMG (Electromyography)

A. REM sleep
B. NREM I sleep (Correct Answer)
C. NREM II sleep
D. NREM III sleep

Explanation: ***NREM I sleep*** - This stage is characterized by a transition from wakefulness to sleep, identifiable by the appearance of **slow eye movements** in the EOG and a reduction in EEG frequency with the presence of **theta waves**. - The EMG shows a decrease in muscle tone but without the complete atonia seen in REM sleep. *REM sleep* - **Rapid eye movements** are characteristic in the EOG, and the EEG shows **low-amplitude, mixed-frequency waves** similar to wakefulness. - The EMG would display profound muscle atonia, which is not evident in the provided tracing. *NREM II sleep* - This stage is marked by the presence of **sleep spindles** and **K-complexes** in the EEG, which are absent in the marked area. - Eye movements are generally absent, and muscle activity continues to be low. *NREM III sleep* - This is the deepest stage of sleep, characterized by **high-amplitude, slow-delta waves** (20-50% of the epoch) in the EEG. - Eye movements are typically absent, and muscle tone is very low but not completely absent.

Question 7: What is a likely diagnosis for a patient with persistent fever after treatment for pneumonia?

A. Fungal pneumonia
B. Bronchogenic carcinoma
C. Lung abscess
D. Empyema (pleural effusion with infection) (Correct Answer)

Explanation: ***Empyema (pleural effusion with infection)*** - **Empyema** is a collection of pus in the pleural space, often a complication of pneumonia, and can cause **persistent fever** despite appropriate antibiotic treatment for the initial pneumonia [1]. - The continued presence of infection in the pleural space, which is not directly targeted by standard pneumonia treatment, can lead to prolonged inflammatory symptoms [1]. *Fungal pneumonia* - While fungal pneumonia can cause persistent fever, it typically does not develop *after* treatment for bacterial pneumonia unless the patient is immunocompromised or has specific environmental exposures . - It would usually be considered if initial bacterial treatment failed or if there were specific risk factors for fungal infection. *Bronchogenic carcinoma* - This is a long-term, chronic condition that can cause fever, but it is unlikely to present as a *persistent fever immediately after treatment* for an acute pneumonia episode. - Fever associated with malignancy often has a different pattern and is usually accompanied by other systemic symptoms like weight loss. *Lung abscess* - A **lung abscess** is a pus-filled cavity within the lung parenchyma, which can cause persistent fever. - However, fever from a lung abscess often responds partially to antibiotics, and the diagnosis is usually made earlier during the initial pneumonia course or when treatment fails to resolve the infiltrates.

Question 8: A 45-year-old male presents to the emergency department following a motor vehicle accident. He complains of severe chest pain and difficulty breathing. On examination, he appears distressed, with a respiratory rate of 28 breaths per minute. His oxygen saturation is 88% on room air. There is visible bruising on the chest, X-ray is done which is shown below. Which of the following is seen in this patient?

A. Kussmaul breathing
B. Paradisical breathing
C. Apneustic breathing
D. Bronchial breathing (Correct Answer)

Explanation: ***Bronchial breathing*** - The provided image is a chest X-ray. The question describes a patient with severe chest pain, difficulty breathing, hypoxemia, and visible chest bruising after a motor vehicle accident, which suggests **pulmonary contusion** or **pneumonia**. - In such conditions, **bronchial breathing** might be heard on auscultation due to consolidation or compression of lung tissue. The X-ray shows diffuse infiltrates or opacities indicative of lung injury, making bronchial breathing a plausible physical exam finding. *Kussmaul breathing* - This is a pattern of **deep and labored breathing** associated with severe **metabolic acidosis**, particularly diabetic ketoacidosis. - While the patient is in distress, the chest X-ray and accident history point to acute respiratory injury rather than metabolic acidosis as the primary cause. *Paradisical breathing* - This term is **not a recognized medical breathing pattern**. It appears to be a distracter. - Medical terminology for breathing patterns includes terms like Kussmaul, Cheyne-Stokes, Biot's, etc. *Apneustic breathing* - Characterized by **prolonged inspiratory pauses** followed by short exhalations, indicating severe damage to the **pons (brainstem)**. - This breathing pattern is typically seen with neurological insults like stroke or severe head injury, which is not directly indicated by the information given, although a head injury could theoretically occur in a MVC, it's not the primary finding for the presented complaints and X-ray.

Question 9: Consider the following statements: The clinical features of tension pneumothorax include 1. tracheal shift to contralateral side 2. absent breath sounds on the affected side 3. low output circulatory failure 4. peripheral cyanosis Which of the statements given above is/are correct?

A. 1 and 3 only
B. 1, 2 and 3 (Correct Answer)
C. 2 and 4
D. 1 and 4

Explanation: ***1, 2 and 3*** - **Tracheal deviation to the contralateral side** is a hallmark sign of tension pneumothorax [1], caused by the increasing pressure in the affected hemithorax pushing mediastinal structures away. - **Absent breath sounds on the affected side** result from the complete collapse of the lung and inability of air to enter the pleural space with inspiration [1]. **Low output circulatory failure** occurs due to increased intrathoracic pressure compressing the heart and great vessels, impairing venous return and cardiac output [2]. *1 and 3 only* - While **tracheal shift to the contralateral side** and **low output circulatory failure** [2] are indeed features, this option incorrectly excludes **absent breath sounds on the affected side**, which is a critical clinical finding in tension pneumothorax. - The absence of breath sounds directly reflects the collapsed lung, a primary mechanical consequence of the condition. *2 and 4* - **Absent breath sounds on the affected side** is correct, but **peripheral cyanosis** is not a *primary* or *early* distinguishing feature of tension pneumothorax. While hypoxemia can lead to cyanosis, it's often a late and less specific sign. - This option misses the crucial finding of **tracheal deviation** and the systemic impact of **circulatory failure** [2], which are more direct indicators of the severity and mechanism of tension pneumothorax. *1 and 4* - **Tracheal shift to the contralateral side** is a correct feature. However, **peripheral cyanosis** is a less specific and often later sign compared to the direct mechanical and circulatory effects. - This option incorrectly omits **absent breath sounds on the affected side** and **low output circulatory failure**, both of which are more consistently present and diagnostically important in tension pneumothorax.

Question 10: All of the following criteria are required for diagnosis of obesity hypoventilation syndrome except -

A. PaCO2 > 45 mmHg
B. BMI 30 kg/m2
C. Hypertension (Correct Answer)
D. Sleep disorder breathing

Explanation: ***Hypertension*** - While **hypertension** is a common comorbidity in patients with **obesity hypoventilation syndrome (OHS)**, it is _not_ a diagnostic criterion. - OHS is defined by specific respiratory and obesity-related parameters, not the presence of associated cardiovascular conditions. *BMI $\geq$ 30 kg/m$^2$* - A **body mass index (BMI)** of **30 kg/m$^2$** or greater is a fundamental criterion for diagnosing OHS, as the syndrome is directly linked to obesity. - Severe obesity leads to mechanical compression of the lungs and chest wall, contributing to hypoventilation. *PaCO$_{2}$ > 45 mmHg* - A **daytime arterial partial pressure of carbon dioxide (PaCO$_{2}$)** greater than **45 mmHg** is a key diagnostic criterion, indicating chronic alveolar hypoventilation. - This persistent hypercapnia is present even when other causes like obstructive lung disease have been excluded. *Sleep-disordered breathing* - **Sleep-disordered breathing**, most commonly **obstructive sleep apnea (OSA)**, is almost universally present in OHS patients and is a required diagnostic criterion [1]. - The combination of severe obesity and OSA often leads to the development of chronic hypoventilation [1].

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free