Tracheostomy decannulation

In this chapter we will discuss recommendations from the hterature regarding dec-aruiulation as well as our personal clinical experience. We will comment on the pathophysiology of ventilator dependence, the determination of candidates for weaning from ventilation and tracheostomy, and a stepwise approach to decannulation. Lastly, we will discuss the choices of noninvasive ventilatory supports and techniques that clinicians may utilize, such as lung volume recruitment (LVR), assisted coughing and mechanical airway clearance. 

Chest wall compliance may be reduced in kyphoscoliosis, fibrothorax, or spinal cord injury and lung compliance may be reduced in pulmonary edema, pulmonary fibrosis, and acute respiratory distress syndrome (ARDS) and COPD in the presence of hyperinflation. Airway secretions or bronchoconstriction may contribute to increased airway resistance. Respiratory drive and muscle function may be compromised by anesthetics, sedation, coma, or hypercapnia, and muscle dysfunction may occur in the presence of malnutrition, hypophosphatemia, disuse atrophy, sepsis, myopathies, or limited oxygen delivery (9). The factors that led to a tracheostomy must be optimized prior to decannulation. 

In a study of 91 ventilator users with DMD, 51 went on to require continuous NIPPV for 6.3 4.6 (range to 25) years. None of the 34 full-time NIPPV users who had access to MAC died from respiratory complications, whereas three died from severe cardiomyopathy. Five patients with no breathing capacity were extubated or decannulated to continuous NIPPV and five became continuously dependent on NIPPV for one year or more without ever being hospitalized (15). It has previously been reported that DMD patients undergoing tracheostomy tend to have a prolongation of survival of about seven years but also have a tendency to die from complications related to invasive mechanical ventilation (IMV) (24). 

Few, if any, patients with NMD should be left to develop unexpected ventilatory failure as appropriate assessment, self-management education, and follow-up will identify disease progression and risk of respiratory complications. When ventilatory failure occurs, tracheostomy tubes can be avoided, for the most part, irrespective of the degree of ventilator dependence, with the exception of those with insufficient bulbar-innervated musculature for speech, deglutition, and airway protection. Those with indwelling tracheostomy tubes should be offered decannulation as part of their rehabilitation, irrespective of the extent of their respiratory muscle failure. The only exceptions to this therapy are patients with advanced bulbar ALS or those with rare facioscapulohumeral muscular dystrophy, who lose all bulbar-innervated muscle function and aspirate saliva to the extent of Sao2 remaining below 95% (13). 

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