Additional spirometric maneuvers: tolerance and spirometric parameters

Abstract

Introduction: The aim of this study was to determine the impact of the number of additional spirometric maneuvers on spirometric parameters.

Materials and methods: This clinical trial was conducted at the Polymère clinic in Yaoundé from April to May 2021. Sampling was consecutive and exhaustive for patients with indication for spirometry and by convenience for healthy volunteer subjects. The intervention consisted in performing 3 additional functional vital capacity (FVC) maneuvers after the 8 standard maneuvers. The primary endpoint was a mean deviation relative change in forced expiratory volume at first second or FVC ≥5%. Statistical analysis was performed with R software version 4.1.0.

Results: A total of 158 subjects were included in our study. Females accounted for 51.26%. The median age was 26.5 years (24-45.75 years). Mean relative changes (standard deviation) in FEV1 and FVC were -0.59% (3.52%) and -0.81% (4.32%) respectively. Mean absolute changes in FEV1 and FVC were -14ml (95ml) and -25.5ml (132ml) respectively. No symptoms appeared when the additional maneuvers were performed. There was an independent association between a significant fall in FEV1 and/or FVC and the presence of asthenia at the start of the examination.

Conclusion: Performing more than 8 FVC spirometry maneuvers did not result in a significant drop in FEV1 or FVC values, or in poor tolerance.