Acute Severe Asthma

Abstract

Acute severe asthma remains a major economic and health burden. The natural history of acute decompensations is one of resolution and only about 0.4% of patients succumb overall. Mortality in medical intensive care units is higher but is less than 3% of hospital admissions. "Near-fatal" episodes may be more frequent, but precise figures are lacking. However, about 30% of medical intensive care unit admissions require intubation and mechanical ventilation with mortality of 8%. Morbidity and mortality increase with socioeconomic deprivation and ethnicity. Seventy to 80% of patients in emergency departments clear within 2 hours with standardized care. The relapse rate varies between 7 and 15%, depending on how aggressively the patient is treated. The airway obstruction in the 20-30% of people resistant to adrenergic agonists in the emergency department slowly reverses over 36-48 hours but requires intense treatment to do so. Current therapeutic options for this group consist of ipratropium and corticosteroids in combination with beta2 selective drugs. Even so, such regimens are not optimal and better approaches are needed. The long-term prognosis after a near-fatal episode is poor and mortality may approach 10%.

Mortality in Patients Hospitalized for Asthma Exacerbations in the United States

“…Previous studies that provided estimates of hospital mortality from asthma exacerbations were limited to individual hospitals or intensive care units or were from regions outside the United States. These studies supported a wide range of hospital mortality estimates (0.4-12%) (22)(23)(24). Our findings, based on nationally representative data, indicate that the overall risk of death in patients hospitalized for asthma exacerbations in the United States is 0.5%.…”

Early tracheotomy for acute severe asthma

“…Although there appears to be a trend toward increased survival after mechanical ventilation for patients with acute asthma, ventilation of critically ill asthmatic patients continues to be a potentially perilous venture associated with significant morbidity and mortality. [1] Tracheotomy is often performed when patients fail to wean from ventilation. As reported by Lee et al, [2] patients with early tracheotomy compared with those with delayed tracheotomy showed significantly lower hospital mortality (31.7% vs. 61.7%, P<0.005), pneumonia (5% vs. 25%, P<0.005), and accidental extubation (0% vs. 10%, P=0.03).…”

Assessment of severity measures for acute asthma outcomes: a first step in developing an asthma clinical prediction rule

“…However, assessment of acute asthma severity continues to be difficult and imprecise, in part because of a lack of available objective measures of disease severity and the variability in how individual patients manifest signs and symptoms [5]. Needed are objective, validated, reliable, and practical measures with which clinicians at the bedside can quickly predict acute disease severity, therapeutic response, and relevant outcomes of acute asthma exacerbations.…”