Acute severe asthma

Asthma affects 3—5% of the population and is one of the most common chronic illnesses (7—9). Both the frequency and severity of asthma appear to be increasing (10—13). Acute, severe asthma has the potential to be fatal. The disease may first appear ia childhood and iadividuals so affected can suffer recurrent episodes throughout their Hves or they may "outgrow" the condition at puberty. On the other hand, there is also adult-onset asthma. These people show no symptoms as children or as young adults, but suddenly develop symptoms later ia life. There have been many reports of bronchial infections preceding the appearance of asthma. However it is not known whether these infections contributed to the development of the disease or whether iadividuals who are already predisposed to asthma ate more likely to experience bronchospasms as a result of a bronchial infection (14). 

In acute severe asthma, systemic corticosteroids should be given to all patients who do not respond to initial bron-chodilator therapy and all patients with moderate to severe exacerbations. Corticosteroids attenuate the inflammatory... 

There is no evidence that intravenous corticosteroid administration is more effective than oral administration, and the oral route is preferred in acute severe asthma.3 There are also few data to guide selection of initial corticosteroid doses. Recommended doses for acute severe asthma are shown in Table 11-5, page 227 however, recent data indicate that... 

The addition of ipratropium bromide to inhaled p2-agonist therapy in acute severe asthma improves pulmonary function and decreases hospitalization rates in both adult and pediatric patients.31 The benefit of combining ipratropium and albuterol appears to be greatest in moderate to severe exacerbations, and the combination should be considered first-line therapy in severe exacerbations. 

The optimal treatment of acute severe asthma depends on the severity of the exacerbation (Figs. 11-2 and 11-3). The patient s condition usually deteriorates over several hours, days, or weeks however, rapid deterioration can occur in some patients.3 Gradual deterioration may indicate failure of long-term controller therapy. Patients with rapid deterioration usually respond well to bronchodilator therapy.40 Severity at the time of the evaluation can be estimated by signs and symptoms, but patient response 30 minutes after inhalation of a bronchodilator is the best predictor of outcome.12... 

McFaddden ER Jr. Acute severe asthma. Am J Respir Crit Care Med 2003 168 740-759. 

Albuterol and other inhaled short-acting selective / -agonists are indicated for treatment of intermittent episodes of bronchospasm and are the first treatment of choice for acute severe asthma and EIB. Regular treatment (four times daily) does not improve symptom control over as-needed use. 

Dosages of Drugs for Acute Severe Exacerbations of Asthma in the Emergency Department or Hospital... 

Has not been studied in acute severe asthma No proven advantage of systemic therapy over aerosol Not recommended... 

Systemic corticosteroids (Table 80-4) are indicated in all patients with acute severe asthma not responding completely to initial inhaled /J2-agonist administration (every 20 minutes for three to four doses). Prednisone, 1 to 2 mg/kg/day (up to 40 to 60 mg/day), is administered orally in two divided doses for 3 to 10 days. Because short-term (1 to 2 weeks), high-dose systemic steroids do not produce serious toxicities, the ideal method is to use a short burst and then maintain the patient on appropriate long-term control therapy with inhaled corticosteroids. 

Q88 Zafirlukast is a leukotriene-receptor antagonist. Zafirlukast is used in the treatment of an acute severe asthma attack. 

Acetazolamide is a carbonic anhydrase inhibitor that reduces aqueous humour production and is therefore indicated in glaucoma to reduce the intraocular pressure. Salbutamol is a selective, short-acting beta2-agonist used as a bronchodilator in asthma. Tolbutamide is a short-acting sulphonylurea used in type 2 (non-insulin dependent) diabetes mellitus. Chlorpromazine is an aliphatic neuroleptic antipsychotic drug used in schizophrenia. Zafirlukast is a leukotriene-receptor antagonist that is indicated in the prophylaxis of asthma but should not be used to relieve acute severe asthma. 

Oxymorphone Hypersensitivity to morphine analogs acute asthma attack severe respiratory depression or upper airway obstruction paralytic ileus pulmonary edema secondary to a chemical respiratory irritant. 

The staging and drug treatment for acute severe asthma has changed over the past three decades, comprising primarily of bronchodilators, corticosteroids, and oxygen. A summary flow chart for the... 

Manser R, Reid D, Abramson M. Corticosteroids for acute severe asthma in hospitalised patients. Cochrane Database Syst Rev 2001. 

Steroid therapy is indicated for the control of acute severe asthma. It is thought that the use of short-term intravenous steroid therapy may reduce the need for hospital admission. Several mechanisms have been suggested ... 

Rodrigo GJ, Rodrigo C. Elevated plasma lactate level associated with high dose inhaled albuterol therapy in acute severe asthma. Emerg Med J 2005 22 404-8. 

Mitra A, Bassler D, Goodman K, et al. Intravenous aminophylline for acute severe asthma in children over two years receiving inhaled bronchodilators. Cochrane Database Syst Rev. 2005 CD001276. 

Preliminary studies in animals suggest that airway smooth muscle, like that in the vasculature, is effectively relaxed by nitric oxide. This very lipophilic drug can be inhaled as a gas in acute asthma and dilates the pulmonary blood vessels as well as the airway smooth muscle. Although nitric oxide itself—or nitric oxide donors—may prove of value in acute severe asthma, it appears likely that they will be more useful in pulmonary hypertension (for which nitric oxide is already approved). 

Clinical features of acute severe asthma include ... 

Patients with acute severe asthma should receive supplemental oxygen therapy to maintain arterial oxygen saturation above 90% (above 95% in pregnant women and patients with heart disease). Significant dehydration should be corrected urine specific gravity may help guide therapy in young children, in whom assessment of hydration status may be difficult. 

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