Assessment of Voluntary and Reflex Cough in Patients With ALS

This study aims to assess the presence and the intensity of voluntary and cough reflex in patients with amyotrophic lateral sclerosis (ALS), comparing the results with the healthy control group. The assessment of the cough is fundamental to verify the mechanism of airways protection which is particularly compromised in ALS patients. Objective parameters of voluntary and reflex cough would be measured by the spirometer. The reflex of cough would be elicited by a solution of citric acid through an ultrasonic nebulizer.

Protocol: Volitional Cough assessment by spirometer (Pony FX- Cosmed): a) Forced vital capacity (FVC); b) Volume Tidal; c) Maximum Espiratory Pressure (MEP); d) Maximum Inspiratory Pressure (MIP); e) Peak of Cough Expiratory Flow. Cough Reflex would be trigged by the inhalation of 0.4M of citric acid solution using the ultrasonic nebulizer (MO-03 Norditalia Elettromedicali) connected with the spirometer and the nebulizer via a bidirectional valve. It would be measured the Peak of Cough Expiratory Flow. Participants: It would be recruited 60 subjects at the IRCCS Ospedale San Camillo Venezia (Italy). All participants have to provide informed consent independently. The study group is composed by thirty participants with diagnosis of ALS and the severity score of Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS). The control group consist of thirty healthy subjects matched by aged and sex with the study group. Statistical consideration: The variables measured will be summarized by means and standard deviations or by proportions. Numeric variables MIP-MEP-FVC-Vt-PCEF will be analyzed using the Shapiro-Wilk test to verify the normality of distribution. Depending on the outcome, for the comparison between groups will be used or the t-test (parametric) or the test of Mann Whitney (non-parametric) for independent samples.

Volitional Cough assessment by spirometer: a) Peak Cough Espiratory Flow (PCEF) Cough Reflex Test a) Peak Cough Espiratory Flow (PCEF)

Inclusion Criteria: Diagnosis of ALS Consensus Exclusion Criteria: Smokers Oxygen Therapy Invasive Ventilation Allergy of citrus Asthma

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