Timing of Mechanical Ventilation
Many recent studies have focused on patient outcomes based on when individuals received MV (Beom & Seo 2018; Flanagan et al. 2018; Choi et al. 2013). Some studies defined ET if it was performed in the first 4 days after patient admission or after initiation of MV (Wang et al. 2021; Anand et al. 2020; Wang et al. 2020), while the majority of studies considered ET if it was performed in the first 7 days (Flanagan et al. 2018; Beom & Seo 2018; Holscher et al. 2014; Romero-Ganuza et al. 2011b; Romero et al. 2009). There has been debate as to whether early tracheostomies result in better outcomes, fewer ventilator days, decreased rates of pneumonia, and even cognitive decline.
Mubashir et al. (2021) performed a systematic review with the aim of reviewing the optimal timing of tracheostomy. Among eight studies with a total sample size of 1,220 participants with SCI, ET was associated with a reduction of ICU LOS by 13 days and of MV by 18.30 days compared to LT. There were no significant differences in total pneumonia and mortality rates between groups. The study also showed that patients with cervical SCI were twice as likely to undergo ET compared to patients with thoracic SCI, and that patients with high cervical SCI were more likely to undergo ET compared to patients with low cervical SCI. Foran et al. (2021) performed a systematic review with the same objectives as Mubashir et al. (2021) and included 17 studies with a total sample size of 2072 patients. Compared with LT, ET was associated with a reduced mean duration of MV by 13.91 days, mean ICU LOS by 10.20 days, and mean hospital LOS by 7.39, and with a decreased incidence of VAP; but ET was not associated with short-term mortality.
Discussion
Generally, results favor ET over LT, based on the evidence (two systematic reviews [Foran et al. 2021; Mubashir et al. 2021] and 10 original studies [Anand et al. 2020; Babu et al. 2013; Beom & Seo 2018; Choi et al. 2013; Flanagan et al. 2018; Holscher et al. 2014; Kornblith et al. 2014; Luo et al. 2014; Romero et al. 2009; Romero-Ganuza et al. 2011b]) that showed more positive outcomes (results) if ET was performed.
Ten case control studies and two retrospective charts have examined the use of early vs. late tracheostomy during acute SCI. Beom and Seo (2018) reported no difference in the number of ventilator days between early vs. late patients, while other studies found that early patients had significantly fewer ventilator days compared to late (Anand et al. 2020; Flanagan et al. 2018; Choi et al. 2013; Holscher et al. 2014; Romero-Ganuza et al. 2011b; Romero et al. 2009; Wang et al. 2021; Wang et al. 2020). Multiple studies found that ET patients had significantly fewer ICU days than the late group (Anand et al. 2020; Beom & Seo 2018; Flanagan et al. 2018; Choi et al. 2013; Holscher et al. 2014; Romero et al. 2009; Romero-Ganuza et al. 2011b; Wang et al. 2021), except for one study with no significant results (Babu et al. 2013). Multiple studies have found conflicting results as to whether an ET results in higher rates of medical complications in patients with SCI. Flanagan et al. (2018) found that there were no differences in the number of days to decannulation, rates of pneumonia, or in-hospital mortality between early versus late tracheostomy patients. Choi et al. (2013) and Wang et al. (2020) found similar results, with no significant differences between groups in terms of rates of pneumonia, or tracheal stenosis. Although other case control studies (Anand et al. 2020; Babu et al. 2013; Holscher et al. 2014; Kornblith et al. 2014; Wang et al. 2021) have found an increased risk of pneumonia for LT patients. The large case control by Romero-Ganuza et al. (2011b) (N = 323) found that patients who received an ET had a significantly increased risk of tracheal stenosis, but no significant differences in rates of pneumonia. Specifically, in terms of in-hospital mortality, early tracheostomies had similar rates than LT in the majority of studies (Anand et al. 2020; Romero-Ganuza et al. 2011b; Romero et al. 2009; Flanagan et al. 2018; Wang et al. 2020); with only one study that showed significantly less ICU mortality after ET comparing to LT (Wang et al. 2021).
Conclusion
There is level 3 evidence (from 10 case control studies: Anand et al. 2020; Beom & Seo 2018; Choi et al. 2013; Flanagan et al. 2018; Romero-Ganuza et al. 2011b; Holscher et al. 2014; Kornblith et al. 2014; Romero et al. 2009; Wang et al. 2020; Wang et al. 2021) that ET could provide better outcomes (e.g., ICU mortality, respiratory complications, MV duration, hospital LOS and ICU LOS) than LT in patients with SCI.
There is level 3 evidence (from one case control study: Wang et al. 2021) that ET reduces duration of MV and ICU LOS, mortality, and pneumonia rates, and increases successful weaning rates in patients with cervical SCI who underwent anterior cervical fusion surgery (ACFS).
There is level 3 evidence (from one case control study: Wang et al. 2020) that ET in patients with acute cervical SCI who underwent cervical internal fixation reduces total duration of MV, duration of MV after tracheotomy, duration of indwelling tracheal tube, and hospital LOS.
There is level 3 evidence (from one case control study: Anand et al. 2020) that ET reduces respiratory complications and ICU LOS, and increases ventilator free days in patients with traumatic cervical SCI.
There is level 3 evidence (from one case control study: Beom & Seo 2018) that ET reduces duration of postoperative ICU hospitalization in patients with motor weakness after surgery for traumatic cervical SCI.
There is level 3 evidence (from two case control studies: Beom & Seo 2018; Flanagan et al. 2018) and level 4 evidence (from one case series study: Binder et al. 2016) that higher neurological level of injury, more severe AIS score, cervical spine fractures at the level of C4 or above, and lower mean AIS motor impairment scale score at the time of injury are predictors for ET in patients with SCI.
