Discussion
This study involved 126 UK hospitals reporting on 1605 individual tracheostomies between March and August 2020. During this same period, 7792 patients were recorded by the UK’s Intensive Care National Audit & Research Centre (ICNARC) as receiving advanced respiratory support in England, Wales and Northern Island.22 Gender ratio, mean age and body mass index grouping are all comparable between the COVIDTrach database and the ICNARC database indicating our cohort is representative, and the results are likely generalisable to the UK.
At the time of censoring, all-cause mortality following tracheostomy in our cohort was 18%. This number is likely to rise as 91 patients were still mechanically ventilated and a further 171 had been weaned but were still in hospital. Prospective multicentre studies of general (non-COVID-19) intensive care populations patients report mortality rates of approximately 30% in the first 30 days following tracheostomy.23 24 Direct comparisons to this cohort of patients with COVID-19 cannot, however, be drawn as demographics, comorbidities and underlying pathologies will differ considerably and timing of tracheostomy is usually performed earlier than the median 15 days following intubation reported in this study of patients with COVID-19. National data, reported in the ICNARC registry, indicate that the ICU mortality rate in mechanically ventilated patients with COVID-19 was 47.8%; however, median duration of critical care stay in non-survivors was 10 days (IQR 6, 17).22 Given median time to tracheostomy in our cohort was 15 days, patients with COVID-19 undergoing tracheostomy constitute a preselected population who have survived the acute phase and, in general, would have cardiorespiratory stability and are no longer requiring high-level ventilatory support and high-inspired oxygen concentrations. Nonetheless, our data show that tracheostomy in the setting of SARS-CoV-2 infection is not a futile intervention as previously claimed by expert opinion at the start of the pandemic.16 17
Whether the timing of tracheostomy does influence patient with COVID-19 outcomes is unclear. Early tracheostomy may benefit certain patient groups,25 26 but meta-analyses have failed to show benefit in a general population of critically ill adults.27 28 In our cohort, early tracheostomy was independently associated with higher mortality. Moreover, no association was demonstrated between early tracheostomy and shortened time to successful weaning from ventilation. Cause and effect cannot be directly inferred from these data and only prospective randomised studies could address this important question.
We found no association between method of tracheostomy and likelihood of successful wean from ventilation, mortality, or discharge from hospital. As in non-COVID-19 series, bleeding was more frequent using the open method, although the overall rate of reported bleeding was low. The percutaneous method has several advantages centred around the ability to perform the procedure at the bedside. In contrast, the open method enables safe procedure in those with difficult neck anatomy and enables the surgical workforce to relieve the task from intensive care staff during periods when a critical care department is working at full capacity. The decision over which method to employ should be locally led and depends on expertise available and close interdisciplinary working.
The low rates of reported SARS-COV-2 infection among operators who likely continued to work in other high-risk areas and performed other aerosol generating procedures are encouraging. While asymptomatic cases may have been missed and recall bias may have occurred, the low rates of infection suggest that, with appropriate PPE, the procedure does not pose a high risk of infection with SARS-COV-2 to operators. Our findings are consistent with other series.29 30
Infectivity and viral load is believed to peak around the time of symptom onset and then decline over the following 3–4 days.31 32 Considering the median time from symptom presentation to hospitalisation is 4 days and that tracheostomy is not usually considered until at least 7 days after intubation, the risk of infectivity is predicted to be low even if the procedure is performed between the first and second week of ventilation.3 33 Our results, therefore, do not support guidance suggesting tracheostomy should be delayed until 14–21 days after intubation to reduce the potential for infection among operators.12 14 Similarly, our findings and data showing a positive COVID-19 test does not correlate with risk of infectivity later in the disease process, suggest tracheostomy should not be delayed to achieve a negative COVID-19 test. Delaying in these circumstances defers the potential benefits of tracheostomy and increases the risk of complications relating to prolonged endotracheal intubation without any clear benefit to the patient or operators involved in the procedure.