Asthma acute exacerbation

The dose-response curve for P2-adrenergic agonists is shifted to the right with increased levels of bronchoconstriction. This explains the need for higher and more frequent doses during an acute asthma exacerbation... 

FIGURE 11-2. Home management of acute asthma exacerbation. Patients at risk for asthma-related death should receive immediate clinical attention after initial treatment. PEF, peak expiratory flow. 

Fig. 80-1 depicts the NAEPP stepwise approach for managing chronic asthma. Fig. 80-2 illustrates the recommended therapies for home treatment of acute asthma exacerbations. 

FIGURE 80-2. Home management of acute asthma exacerbation. Patients at risk of asthma-related death should receive immediate clinical attention after initial treatment. Additional therapy may be required. (MDI, metered-dose inhaler PEF, peak expiratory flow.) (Adapted from NHLBI, National Asthma Education and Prevention Program, Expert Panel Report 2. Guidelines for the Diagnosis and Management of Asthma. NIH Publication No. 97-4051. Bethesda, MD U.S. Department of Health and Human Services, 1997.)... 

Levine M, Iliescu ME, Margellos-Anast H, Estar/iau M, Ansell DA. The effects of cocaine and heroin use on intubation rates and hospital utilization in patients with acute asthma exacerbations. Chest 2005 128(4) 1951-7. 

Park CL, Frank AL, Sullivan M, Jindal P, Baxter BD. Influenza vaccination of children during acute asthma exacerbation and concurrent prednisone therapy. Pediatrics 1996 98(2 Pt l) 196-200. 

Clinical use To induce remission of moderate to severe IBD. Once clinical remission is induced, steroids must be tapered. Other uses acute asthma exacerbations, arthritis, collagen diseases, immunosuppression for organ transplantation. 

Stimulation of nicotinic receptors produces small pupils, blurred vision, excessive perspiration, salivation and lacrimation, bradycardia, increased intestinal peristalsis, increased pulmonary secretions, and decreased blood pressure. Acute asthma exacerbations may occur in patients with reactive airway disease. The onset is typically within 15-30 min after ingesting the mushrooms but may be delayed by up to 120 min. Nausea and vomiting are often the first symptoms to occur. The rare deaths reported appear to occur from cardiovascular collapse and respiratory failure. 

The National Asthma Education and Prevention Program recommends inhaled SAB As be used as needed for acute asthma exacerbation. The usual dose is 360 to 720 pg per four to eight puffs every 20 minutes up to 4 hours for albuterol metered-dose inhaler (MDI). This recommendation contrasts with previous ones for regular use of 180 pg per two puffs for albuterol MDI three to four times daily. Regular use of SABAs has been a standard approach without the scientific basis since 1970s [12]. Current guidelines indicate that inhaled LABAs (usual dose, 84 pg per two puffs for salmeterol MDI twice daily) should be combined with ICSs for asthma control, rather than used as a stand-alone therapy. 

Cote J, Bowie DM, Robichaud P, et al Evaluation of two different educational interventions for adult patients consulting with an acute asthma exacerbation. Am J Respir Crit Care Med 2001 163 1415-1419. (Ib)... 

Figures 26-6 and 26-7 illustrate the recommended therapies for the treatment of acute asthma exacerbations in home and emergency department/hospital settings, respectively. The dosages of the drugs for acute severe asthma are provided in Table 26-6. Institutions should strongly consider developing critical-pathways/treatment algorithms for their emergency departments because their implementation has been shown to improve outcomes and decrease the cost of...

FIGURE 26-7. Emergency department and hospital care of acute asthma exacerbations. (From ref. 2.)... 

Some controversy exists concerning the most cost-effective delivery system (MDI plus holding chamber versus nebulization) to be used in treating severe acute asthma in the emergency department and hospital (see below). The DPIs are currently not indicated for the treatment of severe acute asthma exacerbations. Patients with more severe obstruction may not be able to generate sufficient peak inspiratory flows for adequate delivery. ... 

Multiple daily dosing of systemic corticosteroids for the initial therapy of acute asthma exacerbations appears warranted because receptor-binding affinities of lung corticosteroid receptors are decreased in the face of airway inflammation. However, patients with less severe exacerbations may be treated adequately with once-daily administration. High-dose and very-high-pulse-dose corticosteroid regimens have not been shown to enhance the outcomes in severe acute asthma but are associated with a higher likelihood of side effects. ... 

Both the intensity and duration of response are dose-dependent, and more important, the dose-response relationship is dynamic. At increasing levels of baseline bronchoconstriction (irrespective of the stimulus), the dose-response curve is shifted to the right, and the duration of bronchodilation is decreased. This shift is reflected in the need for higher, more frequent doses in acute asthma exacerbations the duration of protection against significant provocation is much less than the duration of bronchodilation in chronic stable asthma (see Table 26-8). 

Systemic glucocorticoids are used for acute asthma exacerbations and chronic severe asthma. Substantial doses of glucocorticoids (e.g., 40-60 mg prednisone or equivalent daily for 5 days ... 

Respiratory In a prospective multicenter cohort study in 2236 patients with acute asthma exacerbations treated in 115 emergency departments, 1221 (55%) were using no inhaled glucocorticoid or salmeterol (reference group), 48 (2%) were using salmeterol monotherapy, 787 (35%)... 

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