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Summary

The majority of research in the area of early respiratory management is primarily centered on ventilation (including related topics: tracheostomy, intubation and extubation), and the prevention and treatment of pulmonary complications. The emphasis in acute care is to maintain an open airway and diaphragm functioning while preventing respiratory failure, atelectasis, and pneumonia. This is a delicate balance for physicians, as the presence of ventilation itself–despite assisting breathing–can directly lead to these pulmonary complications. Another finding from this review is that less than ten percent of studies to date are in the form of RCTs; the majority are retrospective studies examining which initial factors at admission are associated with certain interventions and outcomes. This suggests a lack of rigorous research in the area of acute respiratory care during acute SCI. Effective RCTs may be difficult to undertake in this research area as there are often standard protocols in place for airway management; further, it may be unethical to create a control group that receives less than the highest quality of pulmonary resuscitation (Casha & Christie, 2011). Lastly, a common theme emerging throughout this chapter is that individuals with complete, high level injuries tend to require more mechanical ventilation, intubation, and tracheostomies than individuals with incomplete or lower level injuries. These patients also experience more pulmonary complications and have more difficulty weaning from ventilation. It is this patient demographic that would benefit most from prospective RCTs in respiratory management, which would allow for improved acute care and rehabilitation outcomes.

Injury Level and Severity

There is level 4 evidence (from two case series; Lertudomphonwanit et al. 2014; Claxton et al. 1998) that complete injuries and injuries C4 and above predict the need for mechanical ventilation in acute SCI patients.

There is level 2 evidence (from two case series and one cohort study; Seidl et al. 2010; Velmahos et al. 2003; Iwashita et al. 2006) that complete injuries predict the need for intubation in acute SCI patients.

There is level 2 evidence (from one cohort study and one case series; Iwashita et al. 2006; Velmahos et al. 2003) that higher level cervical injuries predict the need for intubation in acute SCI patients.

There is level 2 evidence (from four case controls, one case series and one cohort study; McCully et al. 2014; Menaker et al. 2013; Yugue et al. 2012; Harrop et al. 2004; O’Keeffe et al. 2004; Leelapattana et al. 2012) that complete injuries predict the need for tracheostomy in acute SCI patients.

There is level 3 evidence (from two case controls and three case series; McCully et al. 2014; Yugue et al. 2012; Romero-Ganuza et al. 2011a; Seidl et al. 2010; Biering-Sorensen and Biering-Sorensen 1992) that having a cervical level of injury predicts the need for tracheostomy in acute SCI patients.

There is level 4 evidence (from two case series; Nakashima et al. 2013; Call et al. 2011) that higher level SCI correlates with lower rates of decannulation and extubation in acute SCI patients.

There is level 3 evidence (from one case control, one case series and three observational studies; Hassid et al. 2008; Lemons and Wagner 1994; Huang and Ou 2014; Chen et al. 2013; Aarabi et al. 2012) that respiratory complications are associated with more severe injuries among acute SCI patients.

Tracheostomy

There is level 2 evidence (from one cohort study, one case control and one case series; Leelapattana et al. 2012; McCully et al. 2014; Kornblith et al. 2014) that acute SCI patients who have had a tracheostomy experience a longer duration of mechanical ventilation compared to those who have not had a tracheostomy.

There is level 2 evidence (from one cohort study; Leelapattana et al. 2012) that acute SCI patients who have tracheostomies experience fewer respiratory complications than those who do not have tracheostomies. However, there is level 3 evidence (from one case control and one case series; Harrop et al. 2004; Kornblith et al. 2014) that tracheostomy in acute SCI patients is associated with increased respiratory complications and morbidity compared to patients without tracheostomy.

Timing of Tracheostomy

There is level 4 evidence (from three case series; Choi et al. 2013; Romero-Ganuza et al. 2011a; Romero et al. 2009) that patients who have had an early tracheostomy experience a shorter duration of mechanical ventilation compared to those who have had a late tracheostomy.

There is level 4 evidence (from four case series; Kornblith et al. 2014; Babu et al. 2013; Romero-Ganuza et al. 2011a; Romero et al. 2009) that early tracheostomy reduces the risk of pulmonary complications compared to late tracheostomy in acute SCI patients. However, there is level 4 evidence (from one case series; Choi et al. 2013) that the timing of tracheostomy does not influence the incidence of pulmonary complications in acute SCI patients.

Ventilator Weaning

There is level 4 evidence (from one case series; Kornblith et al. 2014) that acute SCI patients who do not require tracheostomy have a higher success rate of mechanical ventilation weaning compared to those who do require this procedure.

There is level 2 evidence (from one cohort study; Peterson et al. 1999) that higher ventilator tidal volumes may speed up the mechanical ventilation weaning process compared to lower ventilator tidal volumes in acute SCI patients.

There is level 3 evidence (from one case control; Peterson et al. 1994) that progressive ventilator-free breathing is a more successful method of weaning acute cervical SCI patients from mechanical ventilation than intermittent mandatory ventilation.

Treatment

There is level 2 evidence (from one RCT; Pillastrini et al. 2006) in support of mechanical insufflation/exsufflation as an effective adjunctive therapy to the use of respiratory kinesitherapy for bronchial clearance in acute SCI patients.

There is level 1b evidence (from one RCT; Barratt et al. 2012) that bronchodilator therapy with salbutamol improves pulmonary function compared to placebo in acute SCI patients.

There is level 1b evidence (from one RCT; Li et al. 2012) that high-dose ambroxol reduces postoperative respiratory complications and increases blood oxygenation post surgery compared to placebo in acute cervical SCI patients.

There is level 1b evidence (from two RCTs; Postma et al. (2014); Derrickson et al. 1992) in support of resistive inspiratory muscle training as an effective means to improve respiratory muscle function in acute SCI patients.

There is level 3 evidence (from one case control; Berney et al. 2002) that extubation and intensive physiotherapy reduces length of stay in intensive care in acute SCI patients.

Hospital Systems

There is level 3 evidence (from one pre-post test; Wong et al. 2012) that the implementation of specialized respiratory management results in stabilization and improvement of respiratory status in acute SCI patients.

There is level 2 evidence (from one cohort study; Cameron et al. 2009) that the tracheostomy review and management service reduces length of hospital stay and duration of cannulation while increasing speech valve usage in acute SCI patients.

There is level 2 evidence (from one cohort study; Vitaz et al. 2001) that the use of a clinical care pathway reduces length of hospital stay and results in fewer complications in acute SCI patients.