EM@3AM – Acute Asthma Exacerbation

Author: Erica Simon, DO, MHA (@E_M_Simon, EM Chief Resident, SAUSHEC, USAF) // Edited by: Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UT Southwestern Medical Center / Parkland Memorial Hospital) and Brit Long, MD (@long_brit, EM Attending Physician, SAUSHEC, USAF)

Welcome to EM@3AM, an emdocs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

A 19-year-old male with a previous medical history of mild persistent asthma (budesonide and albuterol therapy) presents to the emergency department for shortness of breath. Upon entering the room, you find a diaphoretic male speaking in three word sentences.  He conveys an HPI remarkable for a recent upper respiratory infection.

Initial VS: BP 121/77, HR 114, T 98.4F Oral, RR 36, SpO2 88% on room air.

Physical examination is notable for:
General: well developed, thin male; leaning forward on the stretcher, intermittently gasping
CV: tachycardia; no murmurs, rubs, or gallops
Pulm: diffuse inspiratory and expiratory wheezes; supraclavicular and intercostal retractions

What’s the next step in your evaluation and treatment?

Answer: Acute Asthma Exacerbation^1-8

• Epidemiology:¹ In the U.S., approximately 18.4 million adults (age >18) and 6.2 million children suffer from asthma. Greater than 1.6 million annual ED visits occur secondary to asthma-related complaints, and in 2014, asthma exacerbations were responsible for the deaths of 3,651 individuals.
• Underlying etiologies:² Viral infections (most common trigger in children³), exposure to allergens (dust mites, pet dander, molds, cockroaches, etc.), or smoking/second-hand smoke.
• Evaluation and Treatment:
  • Assess the ABCs.
  • Perform a thorough H&P:
    • Question regarding triggers => may ultimately lead to direction to avoid unnecessary exposures (e.g. goodbye new family cat).
    • Discuss the presence or absence of an asthma care plan. Many patients with recurrent exacerbations will have an established algorithm directing home asthma care. Home care plan fail => more likely to require admission.²
    • Question specifically regarding previous exacerbations (i.e. oral steroid therapy, hospitalizations, and intubations) for insight regarding control of the patient’s chronic disease and his/her historical response to therapy.
  • National Institute of Health’s Guidelines for the management of asthma exacerbations:⁴
    • Administer oxygen to relieve hypoxemia.
    • Deliver a short acting beta-agonist (SABA) to relieve airflow obstruction (add ipratropium for moderate to severe exacerbations).
    • Give systemic corticosteroids to decrease airway inflammation in moderate or severe exacerbations or for patients who fail to respond promptly and completely to SABAs.
    • Consider adjunct therapy in patients with severe exacerbations unresponsive to the above (heliox, magnesium sulfate, etc.)
    • Monitor patient response to therapy with serial measurements of lung function.
    • Prevent relapse and recurrence: ensure referral for asthma care within 1-4 weeks, create an ED asthma discharge plan (with indications for increasing medication therapy or seeking medical care for worsening symptoms), review inhaler techniques, and consider initiation of inhaled corticosteroids if appropriate (perform an asthma severity assessment).
  •  Non-invasive positive pressure ventilation should be considered for all patients who display: moderate to severe dyspnea or respiratory distress, hypercapnic acidosis, a respiratory rate > 25/min, accessory muscle use, or paradoxical breathing.⁵
    • In a retrospective cohort study published in 2010, Murase, et al.⁶ found that NIPPV reduced the rate of endotracheal intubation from 18% (9/50 patients) to 3.5% (2/57, p = 0.01).
  •  Patients requiring intubation and mechanical ventilation:
    • Ventilator settings: Assist Control, RR 8-10 (permissive hypercapnea), TV 5-7 cc/kg IBW, PEEP 0, FiO2 titrated to SpO2 > 90%; goal plateau pressure < 30⁷ 
    • Continuous SABA, ipratropium, IV corticosteroids, and ICU admission⁷ 

• Pearls:
  • In 2009, Tsai, et al.⁸ highlighted the value of adherence to the NIH Asthma Guidelines: retrospective chart review (63 urban ED’s in 23 states from 2003-2006, n = 4,053):
    • Patient guideline concordance score: 67 (deemed moderate concordance):
      • When adjusted for severity, patients who received all recommended treatments had a 46% reduction in the risk of hospital admission compared to others.

References:

1. Centers for Disease Control and Prevention. Asthma. Available from: https://www.cdc.gov/nchs/fastats/asthma.htm
2. Jackson D, Lemanske R, Guilbert T. Management of Asthma in Infants and Children. In Middleton’s Allergy: Principles and Practice. 8^th ed. Philadelphia, Saunders. 2014; 53:876-891.
3. Johnston S. Natural and experimental rhinovirus infections of the lower respiratory tract. Am J Resp Crit Care Med. 1995; 152:S46-52.
4. National Hearth, Lung, and Blood Institute. Guidelines for the Diagnosis and Management of Asthma (EPR-3). Available from: https://www.nhlbi.nih.gov/health-pro/guidelines/current/asthma-guidelines/full-report
5. Hill M. Noninvasive Ventilation. Am J Respir Crit Care Med. 2001; 163:540-577.
6. Murase K, Tomil K, Chin K, et al. The use of non-invasive ventilation for life-threatening asthma attacks: Changes in the need for intubation. Respirology 2010; 15:714-720.
7. Tuxen D, Naughton M. Acute Severe Asthma. In Oh’s Intensive Care Manual. 7^th ed. Philadelphia, Elsevier. 2014: 35; 401-413.e5.
8. Tsai C, Sullivan A, Gordon J, Kaushal R, Magid D, et al. Quality of care for acute asthma in 63 US emergency departments. J Allergy Clin Immunol. 2009; 123(2):354-361.

For Additional Reading:

 Mechanical Ventilation for Severe Asthma:

Mechanical Ventilation for Severe Asthma