Symptomatic treatment of respiratory and nutritional failure in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characte rised by death of upper and lower motor neurones. Nutritional and respirato ry failure occurs in most patients with ALS. Nutritional failure occurs pri marily as a result of dysphagia, although malnutrition may also develop in the absence of clinically apparent dysphagia. The optimal management of nut rition in early ALS has not been established. In later stages of the diseas e, parenteral nutritional support using percutaneous endoscopic gastrostomy confers a significant survival benefit in selected patients. Respiratory f ailure occurs as a result of bulbar, cervical and thoracic loss of motor ne urones. Inspiratory muscles are preferentially affected. Management of resp iratory failure includes the use of strategies that limit aspiration pneumo nia, the reduction in secretions, and positioning of the patient to a maxim al mechanical advantage. Use of non-invasive positive pressure ventilation in appropriate patients significantly enhances survival. The decision to un dertake invasive mechanical ventilation should be made prior to the develop ment of symptoms that might warrant this intervention. The progressive natu re of the condition should be taken into account when such a decision is di scussed with the patient and carer. Further studies are required to determi ne the optimal nutritional requirements of patients with ALS, and to elucid ate the physiological changes involved in the decline in respiratory functi on.