Introduction
Coronavirus disease 2019 (COVID-19) has rapidly evolved into a pandemic
since the first report emerged from China in December 20191. With the number of cases rising globally at an
exponential rate and with over 10% of these requiring Intensive Care
Unit (ICU) admission, demand for critical care increasingly threatens to
exceed capacity even among the world’s most advanced economies2. At present, supportive treatment forms the basis of
therapy, with trials currently ongoing to unearth the optimal medicinal
treatment regimen and vaccine. Tracheotomy, through its ability to wean
patients off ventilation, can shorten the ICU length of stay and in
doing so increase ICU bed capacity; crucial for saving lives at a
population level. 3,4 Median ICU stay for COVID-19
patients varies widely between countries ranging between 4 to over 20
days. 5
Tracheotomy constitutes an Aerosol Generating Procedure (AGP), thus
potentially exposing the operating surgeon and Operating Room (OR) team
to respiratory droplets from the SARS-CoV-2 infected patient6. With this added risk in mind it is vital that the
potential benefits of a reduced ICU stay associated with performing a
tracheotomy are balanced against the risks to healthcare professionals.
Despite a number of authors having already published guidelines to
minimize risks to healthcare personnel when performing tracheotomy in
the COVID-19 positive patient7-11, there is currently
a paucity of literature on patient selection criteria for this procedure
and outcomes data for patients who have undergone tracheotomy in these
circumstances. To address this, we present our data from the first 12
COVID-19 patients that underwent tracheotomy in our institution, and
propose parameters to inform patient selection by identifying those
patients who may be more likely to benefit from the procedure.
Furthermore, we discuss potential predictive factors that may help
clinicians identify at an early stage (48h post-operatively) those
patients who are likely to have a positive outcome post-tracheotomy,
which may facilitate decisions to step-down patient care and thus
improve the availability of critical care resources to those patients
that need it most.
Methods
This was a prospective study of all COVID-19 patients undergoing
tracheotomy (n=12) in a Head & Neck Unit in the United Kingdom during a
4-week period (March-April 2020). Anesthesiological processes and
surgical steps pre- and peri-tracheostomy insertion were standardised to
minimise risk to staff and improve patient safety during this crucial
part of the procedure (see Supplementary Material). Recordings of the
patient’s Fraction of Inspired Oxygen (FiO2) and Peak
End Expiratory Pressure (PEEP) were obtained for the 24 hours preceding
the procedure, and subsequently collected on a daily basis until the
patient was either decannulated and discharged from hospital, or died.
Fluctuations in these values, which occurred due to patient
intervention/movement were removed in order to facilitate calculation of
representative averages for these values. The number of days that
patients were kept under sedation and number of days taken for
decannulation were also recorded.
Following our experience with our first 5 tracheotomies and in
accordance with our local protocol (see Supplementary Material) and
published literature 7–9,we instituted selection
criteria for all subsequent tracheotomies as follows:
- Patients should ideally be at least 14 days post-positive swab result
- Low oxygen requirements (FiO2≤40%), sustained for at
least 24 hours
- Patient able to tolerate clamped tube for 1 min in ICU (‘clamp test’)
- Two failed trials of sedation withholding prior to considering
tracheotomy
- Patients that will not require prone ventilation
Correlation between data sets was determined using the ‘R’ statistical
software (v3.6.1, © The R Foundation, Vienna, Austria). Data were
ranked, and Spearman’s rank correlation coefficient was calculated to
determine association between data sets.