Combined ipratropium and β2-adrenergic receptor agonist in acute asthma

Abstract

Table 2 displays the drug STEPs overview. For the treatment of acute episodes of bronchoconstriction associated with asthma, ipratropium should not be used as monotherapy because it has a slower onset of action than β-agonists and only reverses cholinnergically mediated bronchoconstriction. Despite the relatively large number of studies that have been published evaluating the use of inhaled ipratropium in combination with β-agonist for acute asthma, its role continues to remain unclear. Current expert panel guidelines, however, recommend adding nebulized ipratropium to inhaled β-agonist therapy for severe asthma exacerbations. Ipratropium appears to be a safe and well-tolerated agent as an adjunct to treating acute asthma exacerbations. In conclusion, based on clinical trials, the benefit of adding nebulized ipratropium to β-agonist for acute asthma in adults remains uncertain. Administration of combination therapy might improve airflow and reduce admissions without increasing the risk of adverse events. Combination therapy with ipratropium and β-agonist might be of particular benefit in pediatric patients given that it showed reduced hospital admission rats in children with acute asthma in two trials. The Guidelines for the Diagnosis and Management of Asthma state that ipratropium should be administered to adults or children experiencing acute severe asthma exacerbations (PEFR/FEV1 < 50% predicted) coming to the emergency department or outpatient clinic. If ipratropium is used, it should be given in combination with albuterol by nebulizer. Adults should be administered ipratropium 0.5 mg every 20 minutes for three doses followed by ipratropium 0.5 mg every 2 to 4 hours and albuterol 2.5 to 10 mg every 1 to 4 hours as needed. Children should be administered ipratropium 0.25 mg with albuterol 0.15 mg/kg every 20 minutes for three doses then ipratropium 0.25 mg every 2 to 4 hours and albuterol 0.15 to 0.3 mg/kg every 1 to 4 hours. After the patient attains ≥ 70% of the predicted PEFR/FEV1, ipratropium should be discontinued. It might take up 2 hours for ipratropium to reach its maximal effect on PEFR/FEV1. In addition, systemic corticosteroid therapy should also be started when a patient comes to the emergency department or clinic with acute severe asthma. The desired outcome of this approach is to avoid admitting the patient to the hospital, to improve the patient's quality of life, and to improve patient's satisfaction with health care. Issues that have not sufficiently been addressed in clinical trials are subjective parameters, such as symptom improvement and a patient's perception of whether ipratropium is beneficial. Further trials enrolling patients with PEFR/FEV1 < 50% need to be conducted because most cases of adult asthma studied in clinical trials to date were not defined as severe. Ideally, it would be best to determine which patients show a response to ipratropium administration, and continue to use this adjunctive drug in those selected patients.