Related Experiment Video
Updated: Jun 28, 2025
A Protocol for Comprehensive Assessment of Bulbar Dysfunction in Amyotrophic Lateral Sclerosis ALS
Published on: February 21, 2011
Can We Use the Maximum Phonation Time as a Screening of Pulmonary Forced Vital Capacity in Post-COVID-19 Syndrome
Juliana Alves Souza1, Adriane Schmidt Pasqualoto2, Carla Aparecida Cielo1
1Department of Speech, Hearing and Language Sciences and Postgraduate Program in Human Communication Disorders, Voice Laboratory of he Universidade Federal de Santa Maria (UFSM), Santa Maria, Brazil.
Objective:
To verify the accuracy of the maximum phonation time of the vowel /a/ (MPT/a/), fricative /s/ (MPT/s/), number counting (MPTC), and number reached in this count (CN) to estimate forced vital capacity (FVC) in patients with post-COVID-19 syndrome.
Method:
Cross-sectional study involving adult patients, who were admitted to the intensive care unit and referred to the Post-COVID-19 Rehabilitation Outpatient Clinic. Voice function was assessed using a Vocal Handicap Index (VHI) self-assessment questionnaire and MPT tests. To perform the phonatory tests, the patients remained in a standing posture and were instructed to inhale as much air as possible and, during a single exhalation, at usual pitch and loudness, sustain the emission of /a/ and /s/; and in another breath, to perform the ascending numerical count, starting from the number one up to the highest number they could reach. Pulmonary function was assessed by spirometry. The receiver operating characteristic (ROC) curve was plotted, and FVC values lower than the normal limit by Z-score (fifth percentile) were classified as impaired lung function. The predictive values and likelihood ratios were calculated.
Results:
A total of 70 patients participated, with 20-30% having a high VHI. Approximately 24% had an FVC impairment and significantly low values of MPT/a/, MPT/s/, MPTC, and CN. The test results showed overall accuracy of 70% and the cutoff points of 8.83, 7.50, 8.80, and 13, respectively, with high sensitivity, predictive negative value and low specificity, predictive positive value, and positive likelihood ratio.
Conclusions:
Our results suggest that the MPT has moderate discriminatory power for FVC impairment, indicating that it is not a reliable indicator of pulmonary function in the population studied. Therefore, in patients with an MPT of less than 8.83 seconds, or a CN lower than 13, other criteria should be added to improve the diagnostic accuracy and support the decision to perform more complex investigations.
More Related Videos
Related Concept Videos
01:25Pulmonary Function Tests
Pulmonary Function Tests are crucial diagnostic tools for assessing respiratory function, particularly in patients with chronic respiratory disorders. They comprehensively evaluate lung volumes, ventilatory function, breathing mechanics, diffusion, and gas exchange. These tests help diagnose pulmonary diseases and play a significant role in monitoring disease progression, evaluating disability, and assessing response to therapy.
PFTs involve using a spirometer, a...
01:27Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
01:24Physical Assessment of the Respiratory Tract II: Palpation
Thoracic Palpation
Thoracic palpation detects tenderness, masses, lesions, respiratory excursions, and vocal fremitus. The nurse assesses...
01:22Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
01:24Chest Physiotherapy
Purpose
CPT is primarily used for patients with excessive bronchial secretions who have difficulty clearing...
01:31Respiratory System Abnormal Finding II: Palpation and Auscultation
Palpation Findings
During a respiratory assessment, palpation can reveal several vital abnormalities: