A 23-year-old woman is brought to the emergency department due to an hour of difficulty breathing. She has a history of asthma and has been hospitalized several times with exacerbations. The patient is not compliant with an inhaled corticosteroid but takes albuterol as needed for shortness of breath. She says that the breathing difficulty feels like an asthma attack. The patient was just diagnosed with acute sinusitis following an upper respiratory infection; she took an antibiotic for it earlier this morning. She has used the albuterol inhaler several times since symptom onset. On examination, the patient is in moderate respiratory distress. Temperature is 37.8 C (100 F), blood pressure is 82/50 mm Hg, pulse is 118/min, and respirations are 30/min. Oxygen saturation is 85% on room air. There is no visible jugular venous distension. Chest auscultation reveals audible wheezing bilaterally and prolonged expiration. The abdomen is soft and nontender. An urticarial rash is seen over the trunk and upper extremities, and the extremities are warm. Which of the following is the most appropriate next step in management of this patient?

Question

A 23-year-old woman is brought to the emergency department due to an hour of difficulty breathing.  She has a history of asthma and has been hospitalized several times with exacerbations.  The patient is not compliant with an inhaled corticosteroid but takes albuterol as needed for shortness of breath.  She says that the breathing difficulty feels like an asthma attack.  The patient was just diagnosed with acute sinusitis following an upper respiratory infection; she took an antibiotic for it earlier this morning.  She has used the albuterol inhaler several times since symptom onset.  On examination, the patient is in moderate respiratory distress.  Temperature is 37.8 C (100 F), blood pressure is 82/50 mm Hg, pulse is 118/min, and respirations are 30/min.  Oxygen saturation is 85% on room air.  There is no visible jugular venous distension.  Chest auscultation reveals audible wheezing bilaterally and prolonged expiration.  The abdomen is soft and nontender.  An urticarial rash is seen over the trunk and upper extremities, and the extremities are warm.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d1eb_2cd9_bc81_238323767c88_MD0003_00 This patient with skin findings (eg, urticarial rash), respiratory difficulty (eg, wheezing), and hypotension has anaphylaxis, likely caused by antibiotic exposure. Diagnosing anaphylaxis can be challenging if symptoms are initially attributed to a preexisting medical condition (eg, asthma), as happened with this patient. anaphylaxis Epinephrine is the most important treatment for anaphylaxis. It has alpha-1 and beta-2 agonist effects that quickly cause vasoconstriction, increasing blood pressure, and bronchodilation, improving wheezing. Epinephrine also decreases further systemic release of inflammatory mediators from mast cells and basophils, halting anaphylaxis. Intramuscular injection, performed rapidly, is the preferred route of administration and can be repeated every 5-15-minutes (up to 3 doses) if symptoms persist. treatment When anaphylaxis does not respond to several rounds of intramuscular epinephrine, intravenous epinephrine infusion may be necessary. Epinephrine is not initially administered via this route due to higher risk for dosing errors and cardiac complications (eg, arrhythmias) (Choice D). (Choice A) Continuous inhaled albuterol may relieve bronchospasm in this patient. Unlike epinephrine, it would not improve hypotension and prevent impending circulatory collapse. (Choice B) Endotracheal intubation is performed when prominent upper airway edema (eg, oropharyngeal swelling, stridor) is present in anaphylaxis; it does not directly address lower airway bronchospasm, the source of this patient's respiratory distress. In contrast, rapid epinephrine administration may improve bronchospasm and prevent progression to respiratory failure. In addition, positive pressure ventilation (eg, mechanical ventilation) decreases venous return to the heart and can cause cardiovascular collapse in a hypotensive patient unless hemodynamic support (eg, epinephrine) is underway. (Choice E) Intravenous glucocorticoids (eg, methylprednisolone) are frequently administered as adjunct treatment for anaphylaxis due to their anti-inflammatory effect. However, onset is delayed by several hours, and they do not provide immediate lifesaving treatment (as epinephrine does) for hypotension and respiratory distress. (Choice F) Additional vasopressors (eg, intravenous norepinephrine) may be required for refractory hypotension despite maximal therapy with epinephrine. However, norepinephrine is not first-line therapy; it has negligible beta-2 activity and would not treat this patient's bronchospasm and respiratory distress. (Choice G) Intravenous fluids are used as an adjunct to epinephrine to treat hypotension in anaphylaxis, a form of distributive shock. However, epinephrine is the more critical treatment because it addresses all pathophysiologic processes (eg, vasodilation, vascular leak) and treats bronchospasm. Educational objective: Diagnosing anaphylaxis may be challenging in patients with confounding conditions (eg, asthma), nonclassic presentations (eg, protracted symptoms), or ongoing physiologic shifts (eg, childbirth, dialysis). Intramuscular epinephrine is the most important step in management of anaphylaxis. References: 2012 update: World Allergy Organization guidelines for the assessment and management of anaphylaxis. (http://www.ncbi.nlm.nih.gov/pubmed/22744267) Epinephrine absorption in adults: intramuscular versus subcutaneous injection. (http://www.ncbi.nlm.nih.gov/pubmed/11692118)

A 23-Year-Old Woman Is Brought to the Emergency Department Due