Scarfone RJ, Capraro GA, Zorc JJ, Zhao H. Arch Pediatr Adolesc Med. 2002;156:378–383
Purpose of the Study.
To measure the ability of children and adolescents with acute asthma exacerbations to adhere to the National Heart, Lung, and Blood Institute (NHLBI) guidelines for proper metered-dose inhaler (MDI) and peak flow meter (PFM) techniques and to define characteristics associated with improper use.
Children 2 to 18 years old who came to the emergency department of an urban tertiary care center with an asthma exacerbation (history of at least 2 episodes of wheezing that required bronchodilator therapy).
This is a prospective study where patients were asked to demonstrate their use of a placebo MDI, with or without an Aerochamber (Trudell Medical, London, Ontario, Canada), exactly as they would use it at home. Patients were observed by an investigator. Various variables were assessed including morbidity, patient, parent, and primary care provider factors. The use of PFM was similarly assessed in a separate group of patients. NHLBI recommendations were followed in both groups.
Among 208 patients in the MDI group, approximately 90% of patients were African American and about 60% were Medicaid managed care of self-pay. Seventy-three (35.1%) patients did not use a holding chamber (HC) and 135 (64.9%) used a HC. In both subgroups, about 45% of patients demonstrated multiple steps improperly. Errors were found in all of the steps including shaking, exhaling before MDI usage, inhaling with actuation and holding one’s breath after inhalation. Young ages of the patients and the parents were associated with improper use. In the MDI-HC group, factors significantly associated with improper use were no hospitalizations within the past year, parent assistance with the patient with MDI-HC use, and nondaily use of the MDI-HC. On the other hand, 165 (82.9%) of 199 children who, per national guidelines, should be using a PFM at home, did not. Eighty-two (73.9%) of 111 patients demonstrated perfect performance of all PFM steps.
Among this group of inner-city children with acute asthma there is lack of knowledge and low adherence to proper MDI use. There should be greater emphasis on teaching the appropriate way of using MDIs. In addition, PFM technique was usually correct but they were underused and underprescribed.
This study uniquely evaluated each step of MDIs and PFM use among children with asthma exacerbations in an emergency room (ER) setting. Once again we are reminded of the importance of teaching and reviewing inhaler technique with patients and parents alike. The study also shows that most patients can use peak flow meters correctly although they were not being used. This article challenges us all to do better.