**5. Contraindications to noninvasive aids: Invasive ventilatory support**

Certain patient populations are better managed with tracheostomy. Contraindications to noninvasive aid include ventilator dependence with depressed cognitive function, orthopedic conditions interfering with noninvasive interface use, restrictive pulmonary syndrome along with severe pulmonary disease necessitating high FiO2, or uncontrolled seizures or substance abuse (Waldhornet al., 1990). In addition, the presence of a nasogastric tube can hamper the fitting of a nasal interface and the use of mouthpiece or nasal NIV by limiting soft palate closure of the pharynx and the necessary seal at the nose. For neuromuscular disease patients, only those with severe bulbar dysfunction, as observed with severe bulbar ALS resulting in the inability for protect the airway, require tracheotomy (Bach et al., 2004). Other than for the occasional spinal muscular atrophy type 1 patient, tracheotomy is rarely if ever indicated for Duchenne muscular dystrophy or any other neuromuscular disease (Bach et al., 2009). Although tracheostomy ventilation can support alveolar ventilation and extend survival for many NMD patients (Bach, 1996), morbidity and mortality outcomes are not as favorable as by noninvasive approaches (Bach et al., 1998; Toussaint et al., 2006).
