Teste da apneia inspiratória e expiratória para triagem de doenças pulmonares

Abstract

Introduction: the voluntary apnea test (AT) is a simple and rapid test that consists of measuring the duration of inspiratory and expiratory apnea. It is clinically useful and can help in diagnostic screening in primary health care. The actual literature does not present any correlation between AT and obstructive and restrictive ventilatory disorders, and that it could help as an alternative diagnostic method for population screening. The objective is to determine the value of the Maximum Inspiratory Voluntary Apnea Time (MAVIT) and the Maximum Expiratory Voluntary Apnea Time (MIVAT) and correlate them with the spirometric parameters FVC, FEV1, FVC/FEV1, FEF25-75%, FEF50%, FEF75%, TEF25-75%, FEFmax and MVV. Methods: this described and cross-sectional study selected participants into abnormal groups (obstructive or restrictive ventilatory defects in spirometry) and normal groups (spirometry within normal limits). MIVAT and MEVAT values were evaluated using the area under the ROC (receiver operating characteristic) curve regarding their reliability in predicting normal and abnormal spirometric results. Results: the study included 293 participants, 178 individuals with normal spirometry and 115 with ventilatory disorders. MIVAT and MEVAT obtained lower values for the abnormal inspiratory and expiratory groups, respectively: 29.32s (95% CI: 25.99–32.35s) and 20.40s (95% CI: 18.66–22.88s) in relation to the normal inspiratory, and in expiratory groups, respectively: 47.55s (95% CI 43.93–51.87s) and 28.53s (95% CI: 26.74–30.63s). To identify the prediction of normal spirometry, the MIVAT value should be >45.49s with sensitivity of 90.43% and specificity of 55.06%. In addition, METAV showed that the value ≥32.86s had sensitivity and specificity of 90.43% and 33.71%. AT showed weak correlation with FVC, FEV1, FEV1/FVC, FEFmax and MVV. Conclusion: AT is a bedside, low-cost and safe method to assess pulmonary ventilation; as an innovative approach to a long-known test, it provides a useful functional assessment independent of spirometry and can be used for population screening of ventilatory disorders in primary care.