Asthma exacerbations are periods of acute worsening of asthma symptoms that may be life-threatening. Exacerbations are commonly triggered by viral URIs, but other triggers also can be involved. Symptoms often include increased dyspnea, wheezing, and chest tightness. Physical examination can reveal tachypnea, tachycardia, and lung hyperinflation. Pulmonary function testing reveals a reduction in FEV1 and PEF. Hypoxemia can result; Pco2 is usually reduced due to hyperventilation. Normal or rising Pco2 can signal impending respiratory failure.
| TREATMENT | ||
Asthma ExacerbationsThe mainstays of asthma exacerbation treatment are high doses of SABAs and systemic corticosteroids. SABAs may be administered by nebulizer or metered-dose inhaler with a spacer; very frequent dosing (q1h or more often) may be required initially. Inhaled anticholinergic bronchodilator medication can be added to the SABAs. IV corticosteroids, such as methylprednisolone (e.g., 80 mg IV q8h), may be used, although oral corticosteroids (e.g., prednisone 30-45 mg once daily for 5-10 days) also may be used. Supplemental oxygen should be provided to maintain adequate oxygen saturation (>90%). If respiratory failure occurs, mechanical ventilation should be instituted, with care to minimize airway pressures and auto-PEEP. Because bacterial infections rarely trigger asthma exacerbations, antibiotics are not routinely administered unless there are signs of pneumonia. In an effort to treat asthma exacerbations before they become severe, asthma pts should receive written action plans with instructions for self-initiation of treatment based on respiratory symptoms and reductions in PEF. |