Progressive Neuromuscular and Degenerative Diseases

University of Medicine and Dentistry of New Jersey-The New Jersey Medical School, Newark, New Jersey, U.S.A. 

Patients with neuromuscular disorders (NMD) develop ventilatory failure because of a combination of dysfunctions of the inspiratoiy, expiratory, and bulbar-innervated muscles. Respiratory failure and the need for a tracheostomy are avoidable in most cases, using the approaches and interventions presented in this chapter. 

Ventilatory impairment results from inspiratory muscle weakness, central hypoventilation, thoracic restriction, upper airway narrowing, extreme obesity, abdominal distension, and improperly fitting thoracolumbar orthoses. In NMD, pulmonary infiltrates and respiratory failure are precipitated by mucus plugging due to an ineffective secretion clearance, especially during acute respiratory infections (2,7). 

Patients with advanced ventilatory muscle dysfunction develop a rapid, shallow breathing pattern with an inability to take deep breaths, leading to chronic microatelectasis and decreased lung and chest wall compliance (8,9). Acute respiratory tract infections with 

Malnutrition, acidosis, electrolyte disturbances, cachexia, infection, fatigue, and muscle dysfunction, aU exacerbate ventilatory insufficiency. Narcotics, sedatives, and supplemental oxygen reduce ventilatory drive and exacerbate alveolar hypoventilaticm. 

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