A 27-year-old man comes to the emergency department with sudden onset of shortness of breath. He ran out of his asthma medication 10 days ago. He has been intubated twice in the past 6 months due to severe asthma exacerbations. On physical examination, his temperature is 37.2 C (99 F), blood pressure is 142/64 mm Hg, heart rate is 110/min, and respirations are 28/min. His oxygen saturation is 84% on room air and improves to 94% on nonrebreather mask. The patient is alert but appears to be in respiratory distress with some use of accessory muscles of respiration. His lung examination shows equal, bilateral air entry with diffuse wheezing throughout both lung fields. His peak expiratory flow rate is 60% of his personal best, based on his prior admissions.
Which of the following is the most appropriate next step in management of this patient?

Question

A 27-year-old man comes to the emergency department with sudden onset of shortness of breath.  He ran out of his asthma medication 10 days ago.  He has been intubated twice in the past 6 months due to severe asthma exacerbations.  On physical examination, his temperature is 37.2 C (99 F), blood pressure is 142/64 mm Hg, heart rate is 110/min, and respirations are 28/min.  His oxygen saturation is 84% on room air and improves to 94% on nonrebreather mask.  The patient is alert but appears to be in respiratory distress with some use of accessory muscles of respiration.  His lung examination shows equal, bilateral air entry with diffuse wheezing throughout both lung fields.  His peak expiratory flow rate is 60% of his personal best, based on his prior admissions. 
Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c074_9946_8f63_1b2f766569d3_MD0005_00 Early treatment of acute asthma exacerbation is crucial in preventing significant morbidity and mortality. Severity of airflow limitation is assessed using peak expiratory flow (PEF). PEF (40%-69% of baseline) is considered a mild to moderate exacerbation. These patients should be started on inhaled short- acting beta agonists (SABA) for rapid correction of bronchospasm. Patients with PEF <40% should receive high-dose SABA with ipratropium. Serial PEF measurements are used to assess response to treatment. Major side effects of SABA are tachycardia and tremors. Tachycardia in asthma exacerbation is due to hypoxia, which stimulates carotid chemoreceptors to increase catecholamine secretion from the adrenal medulla. Correction of bronchospasm to improve ventilation and hypoxia is most effectively achieved with SABA. Therefore, pre-existing tachycardia is not a contraindication to SABA use. (Choice A) Parenteral magnesium sulfate is a bronchodilator. It is indicated when the PEF is <40% despite >1 hour of intensive therapy with inhaled SABA and glucocorticoids. It has not been shown to benefit patients with mild to moderate exacerbations. (Choice B) Patients with acute asthma exacerbation are at risk of deterioration and respiratory failure. They should be monitored in the hospital to assess response to therapy. Patients with moderate exacerbation who have sustained (>1 hour) improvement in PEF to >70% with SABA with or without glucocorticoids may be discharged from the emergency department. (Choice D) Systemic corticosteroids should also be administered early in the treatment of acute asthma exacerbation. Because their effect is usually not apparent in the first few hours, SABA should be used concomitantly. (Choice E) Intravenous theophylline is not effective in acute asthma exacerbations. It may worsen tachyrhythmias, particularly when combined with beta agonists. Educational objective: Peak expiratory flow is <40% of baseline in severe asthma exacerbation and 40%-69% in mild to moderate asthma exacerbation. Inhaled short-acting beta agonists are the first-line treatment regardless of severity. Inhaled ipratropium should also be given with beta agonists in severe asthma exacerbation. References: Expert Panel Report 3: guidelines for the diagnosis and management of asthma - summary report 2007. (http://www.ncbi.nlm.nih.gov/pubmed/17983880) Guideline for the management of acute asthma in adults: 2013 update. (http://www.ncbi.nlm.nih.gov/pubmed/23656743)

A 27-Year-Old Man Comes to the Emergency Department with Sudden