Respiratory muscle testing in amyotrophic lateral sclerosis: a practical approach

Abstract

in amyotrophic lateral sclerosis (aLS), respiratory muscle weakness leads to respiratory failure and death. Non-invasive positive pressure ventilation (NiPPV) appears to reduce lung function decline, thus improving survival and quality-of-life of patients affected by the disease. Unfortunately, clinical features and timing to start NIPPV are not well defined. Starting from recent findings, we examine established and novel tests of respiratory muscle function that could help clinicians decide whether and when to start NIPPV in ALS. Non-invasive tests estimate the function of inspiratory, expiratory, and bulbar muscles, whereas clinical examination allows to assess the overall neurologic and respiratory symptoms and general conditions. Most of the studies recommend that together with a thorough clinical evaluation of the patient according to current guidelines, vital capacity, maximal static and sniff nasal inspiratory pressures, maximal static expiratory pressures and peak cough expiratory flow, and nocturnal pulse oximetry be measured. A sound understanding of physiology can guide the physician also through the current armamentarium for additional supportive treatments for aLS, such as symptomatic drugs and new treatments to manage sialorrhea and thickened saliva, cough assistance, air stacking, and physiotherapy. in conclusion, careful clinical and functional evaluation of respiratory function and patient's preference are key determinants to decide "when" and "to whom" respiratory treatments can be provided.

Comparison of the effects of voluntary and involuntary breath stacking techniques on respiratory mechanics and lung function patterns in tracheostomized patients: a randomized crossover clinical trial

“… 20 The patients who benefit most from IBS are those with a restrictive pattern of lung function, as well as those with neuromuscular disease, such as Duchenne muscular dystrophy, 21 spinal muscular atrophy, 22 congenital muscular dystrophy, 22 and amyotrophic lateral sclerosis. 5 , 23 , 24 Other indications include the postoperative period after cardiac surgery 25 and Parkinson’s disease. 26 …”

Antioxidant Alternatives in the Treatment of Amyotrophic Lateral Sclerosis: A Comprehensive Review

“…Patients with ALS develop weakness, muscle denervation, atrophy and progressive paralysis of all muscles (bulbar and respiratory), dysphagia (Al-Chalabi and Hardiman, 2013;D'Amico et al, 2013;Gowland et al, 2019) and respiratory muscle weakness that leads to respiratory failure and death (Sferrazza-Papa et al, 2018). The survival rate is 3-5 years after the onset of symptoms (Andersen, 2006;Gordon, 2013;Coan and Mitchell, 2015;Wier et al, 2019).…”

Comparison of Two Protocols for the Assessment of Maximal Respiratory Pressures: Spanish Society of Pulmonology and Thoracic Surgery Versus American Thoracic Society/European Respiratory Society

“…Pulmonary rehabilitation is an evidence-based intervention for patients with chronic obstructive pulmonary disease (COPD) and one of its components is the assessment and training of respiratory muscle strength. In patients with neuromuscular diseases, it is also important to determine the strength of respiratory muscles to analyse the effectiveness of cough [2,3]. There are other clinical fields, in which the relevance of maximal respiratory pressures (MRPs) is growing, for example, in people who have suffered a stroke, as they present significantly lower maximal expiratory and inspiratory pressures (MEP and MIP) and its specific training has shown to be effective [4,5].…”