Anaphylaxis management US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for Anaphylaxis management. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Anaphylaxis management US Medical PG Question 1: A 23-year-old man presents to the emergency department with shortness of breath. The patient was at a lunch hosted by his employer. He started to feel his symptoms begin when he started playing football outside with a few of the other employees. The patient has a past medical history of atopic dermatitis and asthma. His temperature is 98.3°F (36.8°C), blood pressure is 87/58 mmHg, pulse is 150/min, respirations are 22/min, and oxygen saturation is 85% on room air. Which of the following is the best next step in management?
- A. Albuterol and prednisone
- B. IV epinephrine
- C. IV fluids and 100% oxygen
- D. Albuterol and norepinephrine
- E. IM epinephrine (Correct Answer)
Anaphylaxis management Explanation: ***IM epinephrine***
- The patient presents with **signs of anaphylaxis**, including acute onset shortness of breath, hypotension (BP 87/58 mmHg), tachycardia (HR 150/min), and hypoxia (SpO2 85%). Given his history of atopic dermatitis and asthma, he is at high risk for severe allergic reactions.
- **Intramuscular epinephrine** is the first-line treatment for anaphylaxis as it acts rapidly to constrict blood vessels, relax airway smooth muscle, and reduce swelling, addressing both cardiovascular collapse and respiratory distress.
*Albuterol and prednisone*
- While **albuterol** (a bronchodilator) might help with bronchoconstriction, and **prednisone** (a corticosteroid) can reduce inflammation, these are not the immediate priority for severe anaphylaxis.
- They act too slowly to counteract the rapid, systemic effects of anaphylaxis, particularly the life-threatening hypotension and airway compromise.
*IV epinephrine*
- **Intravenous epinephrine** is reserved for severe, refractory cases of anaphylaxis, or for patients already receiving IV infusions in a critical care setting.
- Administering IV epinephrine requires careful titration due to the risk of arrhythmias and hypertension, and IM administration is preferred as the initial rapid response.
*IV fluids and 100% oxygen*
- **IV fluids** are crucial to address the distributive shock and hypotension in anaphylaxis, and **100% oxygen** is essential for hypoxia, but these are supportive measures.
- They do not address the underlying immunological mechanism driving the severe allergic reaction as directly and effectively as epinephrine.
*Albuterol and norepinephrine*
- **Albuterol** can help with bronchospasm, but it is insufficient for systemic anaphylaxis. **Norepinephrine** is a potent vasopressor used for severe shock.
- While norepinephrine can raise blood pressure, it does not have the broader beneficial effects of epinephrine on mast cell degranulation, airway dilation, and stabilization of vascular permeability, making it a secondary agent.
Anaphylaxis management US Medical PG Question 2: A 45-year-old woman, suspected of having colon cancer, is advised to undergo a contrast-CT scan of the abdomen. She has no comorbidities and no significant past medical history. There is also no history of drug allergy. However, she reports that she is allergic to certain kinds of seafood. After tests confirm normal renal function, she is taken to the CT scan room where radiocontrast dye is injected intravenously and a CT scan of her abdomen is conducted. While being transferred to her ward, she develops generalized itching and urticarial rashes, with facial angioedema. She becomes dyspneic. Her pulse is 110/min, the blood pressure is 80/50 mm Hg, and the respirations are 30/min. Her upper and lower extremities are pink and warm. What is the most appropriate management of this patient?
- A. Administer broad-spectrum IV antibiotics
- B. Administer vasopressors (norepinephrine and dopamine)
- C. Administer IM epinephrine 1:1,000, followed by steroids and antihistamines (Correct Answer)
- D. Perform IV resuscitation with colloids
- E. Obtain an arterial blood gas analysis
Anaphylaxis management Explanation: ***Administer IM epinephrine 1:1,000, followed by steroids and antihistamines***
- This patient is experiencing **anaphylaxis** due to **radiocontrast dye**, characterized by generalized itching, urticarial rashes, angioedema, dyspnea, hypotension, and tachycardia. **Intramuscular epinephrine (1:1,000 dilution, 0.3-0.5 mg)** is the first-line treatment for anaphylaxis to reverse bronchospasm and hypotension.
- Subsequent administration of **steroids and antihistamines** helps to prevent recurrent or protracted reactions and to reduce inflammatory responses initiated by histamine and other mediators.
*Administer broad-spectrum IV antibiotics*
- This patient's symptoms are consistent with an **allergic reaction (anaphylaxis)**, not an infection, making antibiotics inappropriate.
- There is no clinical evidence of bacterial infection, such as fever, localized inflammation, or signs of sepsis beyond anaphylactic shock.
*Administer vasopressors (norepinephrine and dopamine)*
- While vasopressors can raise blood pressure, they are **second-line agents** for anaphylaxis after epinephrine.
- Epinephrine addresses both the **vasodilation** and **bronchoconstriction** components of anaphylaxis, making it superior as the initial treatment.
*Perform IV resuscitation with colloids*
- **IV fluid resuscitation** is crucial for treating the hypovolemic component of anaphylactic shock, but **crystalloids** are generally preferred over colloids initially.
- **Colloids** do not offer a significant advantage over crystalloids in anaphylaxis, and administering fluids alone would not address the bronchospasm or diffuse mediator release.
*Obtain an arterial blood gas analysis*
- While an ABG can provide information on oxygenation and acid-base status, it is **not the priority** during an acute, life-threatening anaphylactic reaction.
- Immediate management of **airway, breathing, and circulation (ABC)** with epinephrine takes precedence to stabilize the patient.
Anaphylaxis management US Medical PG Question 3: A 10-year-old boy is brought to the emergency room after a fall from a horse. He has severe pain in his right forearm. He has a history of asthma and atopic dermatitis. His current medications include an albuterol inhaler and hydrocortisone cream. Examination shows an open fracture of the right forearm and no other injuries. The patient is given a parenteral infusion of 1 L normal saline, cefazolin, morphine, and ondansetron. The right forearm is covered with a splint. Informed consent for surgery is obtained. Fifteen minutes later, the patient complains of shortness of breath. He has audible wheezing. His temperature is 37.0°C (98.6°F), heart rate is 130/min, respiratory rate is 33/min, and blood pressure is 80/54 mm Hg. Examination shows generalized urticaria and lip swelling. There is no conjunctival edema. Scattered wheezing is heard throughout both lung fields. Which of the following is the most appropriate next step in management?
- A. Endotracheal intubation
- B. Administer intravenous diphenhydramine
- C. Administer intravenous methylprednisolone
- D. Administer vancomycin and piperacillin-tazobactam
- E. Administer intramuscular epinephrine (Correct Answer)
Anaphylaxis management Explanation: ***Administer intramuscular epinephrine***
- The patient is presenting with signs of **anaphylaxis**, including **generalized urticaria**, **lip swelling**, **hypotension** (BP 80/54 mmHg), and **wheezing** (shortness of breath, audible wheezing over both lung fields).
- **Epinephrine** is the first-line treatment for anaphylaxis as it acts on alpha- and beta-adrenergic receptors to reverse bronchospasm, vasodilation, and reduce angioedema.
*Endotracheal intubation*
- While the patient has **wheezing** and shortness of breath, **intubation** is a more aggressive measure usually reserved for impending or actual airway compromise that doesn't respond to initial treatment with epinephrine.
- The immediate priority is to address the systemic allergic reaction with epinephrine, which can prevent the need for intubation by improving bronchospasm and laryngeal edema.
*Administer intravenous diphenhydramine*
- **Diphenhydramine**, an H1 antihistamine, can help with cutaneous symptoms like **urticaria** and itching but does not address the life-threatening aspects of anaphylaxis such as **bronchospasm** and **hypotension**.
- It is used as an adjunct to epinephrine, not as a primary treatment for severe anaphylaxis.
*Administer intravenous methylprednisolone*
- **Corticosteroids** like **methylprednisolone** can help prevent protracted or biphasic anaphylactic reactions but have a delayed onset of action and are not effective in the acute, life-threatening phase of anaphylaxis.
- They are used as an adjunct after epinephrine has been administered to stabilize the patient.
*Administer vancomycin and piperacillin-tazobactam*
- Administering **broad-spectrum antibiotics** like vancomycin and piperacillin-tazobactam would be appropriate for suspected **sepsis** or a severe bacterial infection.
- The patient's symptoms (generalized urticaria, lip swelling, wheezing, and hypotension) are characteristic of **anaphylaxis**, not bacterial sepsis, making antibiotics an inappropriate immediate first-line treatment.
Anaphylaxis management US Medical PG Question 4: A 23-year-old woman comes to the emergency department because of a diffuse, itchy rash and swollen face for 6 hours. That morning, she was diagnosed with an abscess of the lower leg. She underwent treatment with incision and drainage as well as oral antibiotics. She has no history of serious illness. She is not in acute distress. Her temperature is 37.2°C (99°F), pulse is 78/min, and blood pressure is 128/84 mm Hg. Physical examination shows mild swelling of the eyelids and lips. There are multiple erythematous patches and wheals over her upper extremities, back, and abdomen. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. After discontinuing all recently administered drugs and beginning continuous vital sign monitoring, which of the following is the most appropriate next step in management?
- A. Endotracheal intubation and mechanical ventilation
- B. Intramuscular epinephrine and intravenous hydrocortisone administration
- C. Oral diphenhydramine and close monitoring (Correct Answer)
- D. Intravenous famotidine administration
- E. Watchful waiting and regular reassessments
Anaphylaxis management Explanation: ***Oral diphenhydramine and close monitoring***
- The patient presents with **urticaria** (itchy wheals) and **angioedema** (swelling of eyelids and lips) following antibiotic administration, consistent with a mild-to-moderate allergic reaction.
- **Antihistamines** (H1 blockers like diphenhydramine) are **first-line treatment** for urticaria and angioedema, providing symptomatic relief by blocking histamine receptors.
- With stable vital signs and no signs of anaphylaxis, oral antihistamine therapy combined with close monitoring for potential progression is the most appropriate management.
- Monitoring is essential to detect any worsening symptoms that might require escalation of care.
*Watchful waiting and regular reassessments*
- While monitoring is important after discontinuing the offending agent, **watchful waiting alone is insufficient** when a patient has active allergic symptoms like urticaria and angioedema.
- Active symptoms require symptomatic treatment with antihistamines, not just observation.
- This approach would leave the patient symptomatic without addressing the ongoing histamine-mediated reaction.
*Endotracheal intubation and mechanical ventilation*
- This aggressive intervention is only indicated for **impending or actual airway compromise**, such as severe laryngeal edema causing stridor or respiratory failure.
- The patient has clear lungs, stable vital signs, and only mild facial swelling without respiratory symptoms, indicating no immediate threat to airway patency.
*Intramuscular epinephrine and intravenous hydrocortisone administration*
- **Epinephrine** is the first-line treatment for **anaphylaxis**, characterized by respiratory compromise (bronchospasm, stridor) and/or cardiovascular instability (hypotension, tachycardia).
- This patient has **stable vital signs** (normal BP, normal pulse), clear lungs, and no signs of systemic compromise, ruling out anaphylaxis.
- **Hydrocortisone** may be used as adjunctive therapy in severe reactions but is not indicated for uncomplicated urticaria and angioedema.
*Intravenous famotidine administration*
- **Famotidine** (H2 blocker) can be used as **adjunctive therapy** with H1 blockers for allergic reactions but is not first-line treatment.
- H1 antihistamines (like diphenhydramine) are more effective for urticaria and angioedema and should be administered first.
- IV administration is unnecessary when oral route is available and the patient is not in distress.
Anaphylaxis management US Medical PG Question 5: A 29-year-old man is outside his home doing yard work when a bee stings him in the right arm. Within 10 minutes, he reports breathlessness and multiple, circular, pruritic rashes over his right arm. He drives to his family physician’s office for evaluation. His past medical history is significant for hypertension and he takes lisinopril. Known allergies include latex, Hymenoptera, and aspirin. His blood pressure is 118/68 mm Hg; heart rate is 104/min and regular; respiratory rate is 22/min; temperature is 37.7°C (99.8°F). There is non-pitting edema but erythema with raised wheels are present in the region of the right arm. Auscultation of the lungs reveals mild wheezing at the lung bases. Which of the following is the best course of action in the management of this patient?
- A. Go to the emergency department
- B. Methylprednisolone and go to the emergency department
- C. Diphenhydramine and go to the emergency department
- D. Epinephrine and go to the emergency department (Correct Answer)
- E. Albuterol and go to the emergency department
Anaphylaxis management Explanation: ***Epinephrine and go to the emergency department***
- This patient is experiencing **anaphylaxis**, indicated by breathlessness, generalized urticaria, and a known bee sting allergy, which requires immediate treatment with **epinephrine**.
- **Epinephrine** is the first-line and most critical treatment for anaphylaxis as it reverses bronchoconstriction, stabilizes mast cells, and increases blood pressure. After administering epinephrine, prompt transfer to the **emergency department** is essential for monitoring and further management.
*Go to the emergency department*
- While going to the emergency department is necessary, it is not sufficient as the **initial and most critical treatment (epinephrine)** is missing.
- Delaying the administration of epinephrine for anaphylaxis can lead to rapid deterioration and life-threatening complications.
*Methylprednisolone and go to the emergency department*
- **Methylprednisolone (corticosteroids)** can help prevent biphasic anaphylaxis and reduce inflammation but are **not a first-line treatment for acute anaphylaxis** and do not provide immediate relief from bronchospasm or hypotension.
- The immediate priority is addressing the acute symptoms with epinephrine, followed by transport to the emergency department, where corticosteroids may be administered.
*Diphenhydramine and go to the emergency department*
- **Diphenhydramine (an antihistamine)** can help alleviate mild cutaneous symptoms like pruritus and urticaria, but it **does not treat the life-threatening respiratory or cardiovascular symptoms** of anaphylaxis.
- It should not be used as the sole or primary treatment for anaphylaxis, especially in the presence of breathlessness.
*Albuterol and go to the emergency department*
- **Albuterol (a bronchodilator)** can help relieve bronchospasm and breathlessness, but it **does not address other critical aspects of anaphylaxis** such as vasodilation or mast cell stabilization.
- While useful as an adjunct, it is not a substitute for epinephrine in the management of systemic anaphylaxis.
Anaphylaxis management US Medical PG Question 6: A 12-year-old girl is brought to the emergency department by her parents due to severe shortness of breath that started 20 minutes ago. She has a history of asthma and her current treatment regime includes a beta-agonist inhaler as well as a medium-dose corticosteroid inhaler. Her mother tells the physician that her daughter was playing outside with her friends when she suddenly started experiencing difficulty breathing and used her inhaler without improvement. On examination, she is struggling to breathe and with subcostal and intercostal retractions. She is leaning forward, and gasping for air and refuses to lie down on the examination table. Her blood pressure is 130/92 mm Hg, the respirations are 27/min, the pulse is 110/min and O2 saturation is 87%. There is prominent expiratory wheezes in all lung fields. The patient is put on a nonrebreather mask with 100% oxygen. An arterial blood gas is collected and sent for analysis. Which of the following is the most appropriate next step in the management of this patient?
- A. Intramuscular epinephrine
- B. Intravenous corticosteroid
- C. Inhaled ipratropium bromide
- D. Inhaled albuterol (Correct Answer)
- E. Intravenous theophylline
Anaphylaxis management Explanation: ***Inhaled albuterol***
- Given the patient's acute and severe asthma exacerbation, **inhaled albuterol**, a short-acting beta-agonist (SABA), is the most crucial initial bronchodilator to relieve bronchospasm.
- Her symptoms (severe dyspnea, retractions, tachypnea, tachycardia, low oxygen saturation, and prominent wheezing despite prior SABA use) indicate a need for immediate and aggressive bronchodilation.
*Intramuscular epinephrine*
- **Epinephrine** is primarily used for **anaphylaxis** or severe allergic reactions, which is not suggested by this patient's history or presentation (no mention of allergen exposure, urticaria, angioedema, or circulatory collapse typical of anaphylaxis).
- While it has bronchodilatory effects, it is not the first-line treatment for acute asthma exacerbations.
*Intravenous corticosteroid*
- **Systemic corticosteroids** (e.g., prednisone, methylprednisolone) are essential for reducing airway inflammation in moderate to severe asthma exacerbations and preventing relapse.
- However, their onset of action is typically several hours, so they are not the immediate solution for acute bronchospasm but should be administered shortly after initial bronchodilators.
*Inhaled ipratropium bromide*
- **Ipratropium bromide**, an anticholinergic bronchodilator, is often used in conjunction with albuterol for severe asthma exacerbations.
- It provides additional bronchodilation by blocking muscarinic receptors, but albuterol (a SABA) remains the primary and most rapid-acting bronchodilator for acute relief.
*Intravenous theophylline*
- **Theophylline** is a methylxanthine bronchodilator administered intravenously or orally, not by inhalation.
- It is rarely used in acute asthma management due to its narrow therapeutic index, significant side effect profile, requirement for drug level monitoring, and availability of safer, more effective alternatives.
- It may be considered only in refractory cases that do not respond to standard therapy.
Anaphylaxis management US Medical PG Question 7: An 8-year-old girl is brought to the emergency department by her parents with severe difficulty in breathing for an hour. She is struggling to breathe. She was playing outside with her friends, when she suddenly fell to the ground, out of breath. She was diagnosed with asthma one year before and has since been on treatment for it. At present, she is sitting leaning forward with severe retractions of the intercostal muscles. She is unable to lie down. Her parents mentioned that she has already taken several puffs of her inhaler since this episode began but without response. On physical examination, her lungs are hyperresonant to percussion and there is decreased air entry in both of her lungs. Her vital signs show: blood pressure 110/60 mm Hg, pulse 110/min, respirations 22/min, and a peak expiratory flow rate (PEFR) of 50%. She is having difficulty in communicating with the physician. Her blood is sent for evaluation and a chest X-ray is ordered. Her arterial blood gas reports are as follows:
PaO2 50 mm Hg
pH 7.38
PaCO2 47 mm Hg
HCO3 27 mEq/L
Which of the following is the most appropriate next step in management?
- A. Intravenous corticosteroid (Correct Answer)
- B. Inhaled corticosteroid
- C. Mechanical ventilation
- D. Methacholine challenge test
- E. Inhaled β-agonist
Anaphylaxis management Explanation: ***Intravenous corticosteroid***
- The patient exhibits severe asthma exacerbation with **poor response to inhaled β-agonists**, marked respiratory distress, and an alarming **PEFR of 50%**.
- **Intravenous corticosteroids** are crucial in this scenario to reduce airway inflammation and prevent progression to respiratory failure.
*Inhaled corticosteroid*
- While essential for **long-term asthma control**, inhaled corticosteroids are **not effective enough for acute, severe exacerbations** due to their slower onset of action.
- The patient's inability to effectively inhale deeply due to distress also limits the utility of inhaled delivery in this emergency.
*Mechanical ventilation*
- Mechanical ventilation is a **last-resort intervention** for impending respiratory failure, indicated by signs like declining consciousness, hypercapnia, or respiratory arrest.
- While concerning, the patient's current ABG with a **near-normal pH (7.38)** despite hypercapnia suggests she is not yet in full respiratory failure, and less invasive measures should be initiated first.
*Methacholine challenge test*
- The methacholine challenge test is used to **diagnose asthma in stable patients** with normal spirometry, by assessing airway hyperresponsiveness.
- It is **absolutely contraindicated** in an acute, severe asthma exacerbation as it could worsen bronchoconstriction and respiratory distress.
*Inhaled β-agonist*
- The patient has **already taken several puffs of her inhaler** (likely a β-agonist) without response, indicating **refractory bronchospasm**.
- While initially appropriate, repeated administration when ineffective suggests the need for other therapeutic interventions to address the underlying inflammation.
Anaphylaxis management US Medical PG Question 8: A 12-month-old boy presents for a routine checkup. The patient immigrated from the Philippines with his parents a few months ago. No prior immunization records are available. The patient’s mother claims that he had a series of shots at 6 months of age which gave him a severe allergic reaction with swelling of the tongue and the face. She also remembers that he had the same reaction when she introduced solid foods to his diet, including carrots, eggs, and bananas. Which of the following vaccinations are not recommended for this patient?
- A. Measles, mumps, and rubella (MMR) vaccine
- B. Hepatitis B vaccine
- C. Varicella vaccine
- D. Intranasal influenza vaccine
- E. Intramuscular influenza vaccine (Correct Answer)
Anaphylaxis management Explanation: ***Important Note on Current Guidelines***
Based on **current CDC/ACIP guidelines (2023-2024)**, egg allergy alone is **no longer a contraindication** to influenza vaccines. However, this question tests knowledge of vaccine safety in the context of **severe anaphylaxis to a prior vaccination**.
***Intramuscular influenza vaccine***
- **Historically**, this was considered the most concerning option for patients with severe egg allergy, as many influenza vaccines were produced using egg-based culture methods
- **Current practice**: Per CDC guidelines, persons with egg allergy of any severity can receive any age-appropriate influenza vaccine, as egg protein content is minimal or absent in modern formulations
- However, if this patient had a **documented anaphylactic reaction to the influenza vaccine itself** (not just eggs), then it would be contraindicated
- Given the timing (6 months) and symptoms described, this represents the **historically correct answer**, though modern practice has evolved
*Measles, mumps, and rubella (MMR) vaccine*
- MMR vaccine is grown in **chick embryo fibroblast cells**, NOT in eggs, and contains **no egg protein**
- **Safe for patients with egg allergy** - no contraindication based on egg allergy
- Should be administered on schedule for catch-up immunization
*Hepatitis B vaccine*
- Produced using **recombinant DNA technology in yeast cells**
- Contains **no egg protein** and no animal-derived proteins
- **No contraindication** for this patient - safe to administer
*Varicella vaccine*
- Grown in **human diploid cell cultures**, NOT in eggs
- Contains **no egg protein**
- **Safe for patients with egg allergy** - no contraindication
- Should be administered as part of catch-up immunization
*Intranasal influenza vaccine (LAIV)*
- Like the intramuscular formulation, **current guidelines allow administration** to patients with egg allergy of any severity
- Contains similar or less egg protein than inactivated vaccines in modern formulations
- **Not contraindicated** based solely on egg allergy per current CDC guidelines
Anaphylaxis management US Medical PG Question 9: A 16-month-old male patient, with no significant past medical history, is brought into the emergency department for the second time in 5 days with tachypnea, expiratory wheezes and hypoxia. The patient presented to the emergency department initially due to rhinorrhea, fever and cough. He was treated with nasal suctioning and discharged home. The mother states that, over the past 5 days, the patient has started breathing faster with chest retractions. His vital signs are significant for a temperature of 100.7 F, respiratory rate of 45 and oxygen saturation of 90%. What is the most appropriate treatment for this patient?
- A. Albuterol, ipratropium and IV methylprednisolone
- B. IV cefotaxime and IV vancomycin
- C. Intubation and IV cefuroxime
- D. Humidified oxygen, racemic epinephrine and intravenous (IV) dexamethasone
- E. Nasal suctioning, oxygen therapy and IV fluids (Correct Answer)
Anaphylaxis management Explanation: ***Nasal suctioning, oxygen therapy and IV fluids***
- This patient's presentation with rhinorrhea, fever, cough, tachypnea, expiratory wheezes, and hypoxia, particularly a 16-month-old, strongly suggests **bronchiolitis**, likely caused by **RSV**.
- Management of bronchiolitis is primarily **supportive care**, including maintaining airway patency via nasal suctioning, providing oxygen for hypoxia, and ensuring adequate hydration with IV fluids.
*Albuterol, ipratropium and IV methylprednisolone*
- **Bronchodilators** like albuterol and ipratropium are generally **not recommended** for routine management of bronchiolitis due to lack of consistent efficacy in infants.
- **Corticosteroids** (e.g., methylprednisolone) are also **not routinely indicated** for bronchiolitis and have not been shown to improve outcomes.
*IV cefotaxime and IV vancomycin*
- These are **broad-spectrum antibiotics** used to treat **bacterial infections**, such as severe pneumonia or sepsis.
- The clinical presentation is more consistent with a **viral respiratory infection** (bronchiolitis), and there is no evidence of a bacterial co-infection or sepsis.
*Intubation and IV cefuroxime*
- **Intubation** is an invasive procedure reserved for patients with impending respiratory failure and is not indicated at this stage given the current oxygen saturation of 90% with supportive measures.
- **Cefuroxime** is an antibiotic, and like other antibiotics, is not indicated for a viral illness like bronchiolitis.
*Humidified oxygen, racemic epinephrine and intravenous (IV) dexamethasone*
- **Racemic epinephrine** may be considered for severe bronchiolitis with significant bronchospasm, but its use is not routine and its efficacy is debated.
- **IV dexamethasone** is a corticosteroid, which is not recommended for routine bronchiolitis management. Humidified oxygen is helpful, but the overall regimen is not standard for bronchiolitis.
Anaphylaxis management US Medical PG Question 10: A 4-year-old girl is brought to the emergency department by her parents with a sudden onset of breathlessness. She has been having similar episodes over the past few months with a progressive increase in frequency over the past week. They have noticed that the difficulty in breathing is more prominent during the day when she plays in the garden with her siblings. She gets better once she comes indoors. During the episodes, she complains of an inability to breathe and her parents say that she is gasping for breath. Sometimes they hear a noisy wheeze while she breathes. The breathlessness does not disrupt her sleep. On examination, she seems to be in distress with noticeable intercostal retractions. Auscultation reveals a slight expiratory wheeze. According to her history and physical findings, which of the following mechanisms is most likely responsible for this child’s difficulty in breathing?
- A. Defective chloride channel function leading to mucus plugging
- B. Chronic mucus plugging and inflammation leading to impaired mucociliary clearance
- C. Airway hyperreactivity to external allergens causing intermittent airway obstruction (Correct Answer)
- D. Inflammation leading to permanent dilation and destruction of alveoli
- E. Destruction of the elastic layers of bronchial walls leading to abnormal dilation
Anaphylaxis management Explanation: **Airway hyperreactivity to external allergens causing intermittent airway obstruction**
- The child's symptoms of **recurrent breathlessness** and **wheezing**, especially while playing in the garden (suggesting **allergen exposure**), and subsequent improvement indoors, are highly indicative of **allergen-induced bronchoconstriction**.
- The history points to **intermittent airway obstruction** triggered by environmental factors, characteristic of conditions like **asthma** where airways are hyperresponsive to triggers.
*Defective chloride channel function leading to mucus plugging*
- This mechanism is characteristic of **cystic fibrosis**, which typically presents with chronic respiratory issues, recurrent infections, and growth failure, not the acute, intermittent, and allergen-triggered episodes described.
- While mucus plugging can occur, it's a chronic process in cystic fibrosis and doesn't align with the acute, reversible nature and specific triggers mentioned in the case.
*Chronic mucus plugging and inflammation leading to impaired mucociliary clearance*
- This describes conditions like **bronchiectasis** or chronic bronchitis, which involve persistent cough, sputum production, and recurrent infections, rather than acute episodic wheezing based on allergen exposure.
- Impaired mucociliary clearance would lead to more continuous respiratory issues, not the relief experienced upon coming indoors.
*Inflammation leading to permanent dilation and destruction of alveoli*
- This mechanism is characteristic of **emphysema**, a condition primarily seen in adults, typically due to smoking, and presenting with chronic shortness of breath and airflow limitation, rather than episodic, allergen-triggered wheezing in a child.
- Emphysema involves alveolar damage, not primarily bronchial obstruction or hyperreactivity.
*Destruction of the elastic layers of bronchial walls leading to abnormal dilation*
- This describes **bronchiectasis**, which is characterized by permanent dilation of the bronchi, leading to chronic cough with sputum production and recurrent respiratory infections.
- The symptoms presented by the child are acute, reversible episodes of breathlessness and wheezing, not indicative of permanent structural damage to the bronchial walls.
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