Objective: To review the mechanisms involved in the appearance of respiratory failure in patients with neuromuscular disorders.
Development: The development of respiratory failure in patients with weakness of the respiratory muscles secondary to neuromuscular disease is not only due to the disease itself. There are also other mechanisms which contribute in varying degrees. These mechanisms are: 1. Alteration of the mechanical properties of the respiratory apparatus; 2. The appearance of muscle fatigue; 3. Alterations in the control of ventilation; 4. Alterations in gas exchange during the night leading to loss of sensitivity of central and peripheral chemoreceptors. 5. Dysfunction of the upper airway, which favors the appearance of obstructive apnea during sleep. The part played by each of these mechanisms in the development of respiratory failure is different in each individual patient, depending on the type and severity of his particular illness. Ventilatory assistance at night has been shown to be effective in correcting respiratory failure during the day in these patients, probably by acting to a greater or lesser extent on all the different mechanisms involved.
Conclusions: The origin of the respiratory failure seen in patients with neuromuscular diseases is due to many factors. Nocturnal ventilatory assistance is effective since it acts on all the different mechanisms involved.