Respiratory muscle weakness is the main contributor to respiratory imbalance in patients with neuromuscular diseases (NMD). In the advanced stages of the disease, patients develop a chronic respiratory failure due to muscle weakness, which is the principal cause of death among these patients. Respiratory muscle weakness ultimately causes alveolar hypoventilation, initially nocturnal, and later daytime respiratory failure. The signs and symptoms of early respiratory muscle weakness are discrete, namely: dyspnoea on effort, orthopnea, insomnia, frequent nocturnal awakenings, morning headache, loss of appetite, excessive daytime sleepiness, depression, anxiety, and marked fatigue. The management of respiratory failure in neuromuscular diseases requires the use of noninvasive ventilation (NIV) to assist the respiratory muscles in order to correct the alveolar hypoventilation and ameliorate gas exchange. NIV thus slows down the decline of forced vital capacity thereby improving the patient’s quality of life, physical activity and hemodynamics, normalization of blood gases, slight improvement in other physiological measures, and maximal mouth pressures and increases survival. NIV support should be offered to all patients who present with early signs of ventilatory failure as it is probably the most effective among treatments in prolonging life in neuromuscular patients.
Part of the book: Noninvasive Ventilation in Medicine