Discussion
With no established superiority of approach and location of tracheostomy
procedures from the standpoint of infectious transmission, the choice is
determined by balancing the risks to patients and staff, and considering
local expertise and resources.
Performance of surgical tracheostomy in theatre requires availability of
operating rooms, negative-pressure ventilation, staff and equipment,
with the need for multiple disconnection and reconnection of the
breathing circuit. Circuit disconnection could potentially lead to
impaired oxygenation in the critically-ill patient due to loss of
positive end-expiratory pressure (5), and additionally increase exposure
risks to additional personnel during patient transfer. A systematic
review evaluating the available international guidelines for
tracheostomy in COVID-19(6) highlighted the role of bedside tracheostomy
in the Intensive Care Unit (ICU) in negative-pressure rooms. However, it
is generally recognised that the availability of negative pressure air
flow setting both in operating room and ICU is in reality limited and
not a usual part of the UK hospital infrastructure. As with many
institutions that were severely affected with COVID-19, multiple
operating theatre rooms were converted to accommodate the saturation of
ITU beds. These logistical factors, together with scarce operating room
resources, favoured open surgical tracheostomy to be performed by the
bedside in ICU.
The specific challenges of bedside open approach include limited space,
need of transfer of surgical equipment and instruments, and suboptimal
lighting and positioning. This was made more challenging due to the
enhanced PPE and associated impaired communication. We find that in
order to overcome these challenges, bedside open tracheostomies in the
ICU should be standardised and meticulously planned with participation
of highly experienced surgeons, anaesthetist and scrub team
We followed key recommendations in minimising aerosol generation during
open tracheostomy in COVID-19 patients including advancing the
endotracheal tube distal to proposed site of tracheal window prior to
entry, hyperinflation of endotracheal cuff, withholding ventilation at
key points and covering operative site with gauze swabs when ventilation
recommences (7).
A key approach in performing a safe and swift bedside tracheostomy is to
ensure that major bleeding is avoided. Many of the critically ill
tracheostomy candidates will be anticoagulated; making haemostasis even
more crucial. Common source of bleeding is typically from the anterior
jugular veins and from the encountered thyroid gland and its feeding
vessels. A pre-operative ultrasound assessment can be considered in
conjunction with palpation of the neck particularly in in obese patients
or where anatomical landmarks are difficult to assess by palpation. It
provides important anatomical information including distance from skin
to trachea, identification of vulnerable structures, such as thyroid
gland and blood vessels.
We acknowledge and follow the recommendations to limit the use of
diathermy. The evidence surrounding risk of aerosolisation from surgical
smoke plumes is still not fully understood (8), however transmission is
theoretically plausible. Therefore, we opted for vascular clips and and
surgical ties when possible and considered diathermy on case-by-case
basis; balancing the potential risk of aerosolisation with the risk of
intra-operative bleeding. To mitigate theoretical viral transmission
from diathermy plumes, we ensured the use of an extractor suction. Our
practice also includes the use of LigaSure sealing device in cases where
thyroid isthmus division is required. This approach as opposed to
traditional clamping, division and ligation with transfixion sutures; is
considered a less time-consuming option.
Bedside open tracheostomy demonstrated a short mean procedural time of 9
minutes and with no tracheostomy-related complications. The higher
in-hospital mortality and mean time to decannulation may be a reflection
of the inherent selection bias in the bedside tracheostomy group as
these patients are typically selected due to their comorbidities and
higher risk of transfer. Further studies are needed to better understand
this association.