Most frequent errors in inhalation technique of patients with asthma treated at a tertiary care hospital / Erros mais frequentes na técnica inalatória de pacientes com asma brônquica em tratamento em hospital terciário

ABSTRACT Objective: To demonstrate the most frequent errors in inhalation technique in patients with asthma undergoing treatment at a tertiary care hospital. Methods: A cross-sectional study with a convenience sample of asthma patients aged 18 years or over, treated at a pulmonology outpatient clinic of a tertiary care hospital. The assessment of inhalation technique of users of the dry powder inhalers Aerolizer®, Aerocaps and Diskus®, or metered-dose inhalers was based on the manufacturer's instructions for use of each inhaler device. Patients demonstrated the inhalation technique with empty inhaler devices, and it was considered correct when all stages were performed properly, or when errors probably did not interfere with the treatment outcome. Results: Among 71 participants, 43 (60.5%) performed inhalation technique incorrectly. Among metered-dose inhalers and dry powder inhalers users, inhalation technique errors were found in 84.2% and 51.9%, respectively (p=0.013). Errors were more frequent at the exhalation stage (67.4%), followed by breathing in (58.1%) and apnea (51.2%). In the group using dry powder inhalers, the most common errors occurred during exhalation and, for those using metered-dose inhalers, the most compromised stage was aspiration. Conclusion: Errors were more frequent among those using metered-dose inhalers compared with dry powder inhalers. Misconceptions are more common at the expiration stage among users of dry powder inhalers and in aspiration among those on metered-dose inhalers.

RESUMO Objetivo: Demonstrar os erros mais frequentes na técnica inalatória de pacientes com asma brônquica em tratamento em hospital terciário. Métodos: Estudo transversal, com amostra de conveniência de pacientes com asma, com 18 anos ou mais, em tratamento em ambulatório de pneumologia de um hospital terciário. A avaliação da técnica inalatória dos usuários dos dispositivos de pó seco Aerolizer ®, Aerocaps® ou Diskus®, ou de aerossóis dosimetrados teve como base as orientações da bula do fabricante de cada dispositivo inalatório. Os pacientes demonstraram a técnica inalatória com dispositivos inalatórios vazios, e ela foi considerada correta quando todas as etapas foram realizadas de forma apropriada, ou quando os equívocos provavelmente não interferiam no resultado do tratamento. Resultados: Entre os 71 participantes, 43 (60,5%) realizaram a técnica inalatória de forma incorreta. Dentre os usuários de aerossóis dosimetrados e dispositivos de pó seco, ocorreram erros de técnica inalatória em 84,2% e 51,9%, respectivamente (p=0,013). Os erros foram mais frequentes na etapa da expiração (67,4%), seguidos da aspiração (58,1%) e da apneia (51,2%). No grupo que usava dispositivos de pó seco, os erros mais comuns aconteceram na expiração e, nos que utilizavam aerossóis dosimetrados, a etapa mais comprometida foi a aspiração. Conclusão: Os erros foram mais frequentes entre os que usavam aerossóis dosimetrados em comparação com dispositivos de pó seco. Os equívocos foram mais comuns na etapa da expiração entre os usuários de dispositivos de pó seco e na aspiração entre os que usavam aerossóis dosimetrados.

Incorrect use of inhalation devices among patients with bronchial asthma. A hospital-based cross-sectional study in Rio de Janeiro, Brazil

ABSTRACT CONTEXT AND OBJECTIVE: Treatment of asthma implies inhalation of specific drugs to reach high concentrations in the respiratory tree and ensure low drug bioavailability and few adverse effects. This study aimed to evaluate the effectiveness of the inhalation technique among outpatients with asthma. DESIGN AND SETTING: Tertiary-care hospital-based cross-sectional study in Rio de Janeiro. METHODS: We evaluated inhalation practices in a convenience sample. A questionnaire was used to investigate sociodemographic data and assess disease control level, duration of use of the inhalation device, length of treatment and previous instructions provided by the prescribing physician. Patients demonstrated their inhalation technique using empty devices, and their technique was considered correct when all steps were appropriately performed or when errors did not interfere with the treatment outcome. RESULTS: Among the 71 participants, 53 (74.7%) had been using the same inhaler device for at least two years and 41 (57.8%) had been under treatment for two years or more. Twelve (17.1%) said that they had been taught once and 57 (81.4%) at least twice, while one (1.4%) reported not having received any guidance regarding use of inhaler devices. Eighteen patients (25.3%) presented controlled asthma and 28 (39.5%) performed the inhalation technique correctly. Incorrect technique was associated with fewer evaluations of the inhalation technique (P =0.04) and uncontrolled asthma (P = 0.01). CONCLUSIONS: Less than half of the sample performed the inhalation technique correctly. Incorrect inhalation technique was related to lower number of evaluations of the use of the inhalation device and uncontrolled asthma.