The use of mini Wright peak flow meter device as a point-of-care screening tool for obstructive airway disease in resource-limited settings

Abstract

Background: Obstructive airway disease (OAD) is under-diagnosed in India due to unavailability of spirometry. The mini Wright peak flow meter is a simple, inexpensive handheld device that measures peak expiratory flow rates (PEFR). Aim: To determine the accuracy of peak flow meter in screening for OAD, and to test correlation between PEFR measurement by the device and conventional spirometer. Methods: Between Dec 2016-Feb 2017, consecutive subjects undergoing spirometry at PD Hinduja Hospital, Mumbai were offered testing with a mini Wright peak flow meter. Best of 3 records was recorded. Testing was conducted by trained technicians using ATS criteria for quality control. A prebronchodilator FEV1/FVC Results: 957 patients were enrolled and participated in the study.145 subjects (15.15%) had OAD on spirometry. There was excellent correlation between PEFR measurement by the peak flow meter and spirometer(r=0.94). The peak flow meter had a sensitivity of 94.5%(95% CI 89,97) and NPV of 98%(95% CI 96,99) for OAD using 400 l/min as the threshold. Using the normative values of PEFR on spirometry as the threshold, the peak flow meter had a sensitivity of 89%(95% CI 82,93) and NPV of 97.5%(95% CI 96,98);of the 16 false negatives, 14 subjects had mild and 2 had moderate obstruction by GOLD classification. Conclusion: The mini Wright peak flow meter is a sensitive tool for screening of OAD, and can be valuable in resource limited settings. Acknowledgement:The study was supported by a Cipla grant.