2 MATERIALS AND METHODS
2.1 Participants
We analyzed the incidence of infection to healthcare workers and
clinical characteristics of patients with COVID-19 who underwent a
tracheotomy from April 2020 to August 2021. We have performed hybrid
modified percutaneous dilatational tracheotomy in 20 patients with
COVID-19. The patients’ preoperative physical condition was evaluated
using Charlson Comorbidity Index Score (CCIS) and Acute Physiology and
Chronic Health Evaluation II (APACHE II) Score. Mean time from
intubation to the tracheostomy and decannulation, survival rate,
operation time, and complications for tracheostomy were measured.
2.2 Ethical considerations
This study was approved by the Institutional Ethics and Research
Committee of our institution (No. 2021-05-008) and performed in
accordance with the Declaration of Helsinki and good clinical practice
guidelines. All participants provided written informed consent
2.3 Surgical technique
At our institute, tracheostomy is performed in a negative pressure
intensive care unit at a pressure -2.5 Pa by a tracheostomy team
consisting of three individuals, that is, a surgeon (otolaryngologist),
a first assistant (2nd or 3rd -year
residents in the otolaryngology residency program), and a nurse (Figure
1). All members of the team wear level D protective clothing and powered
air-purifying respirator (PAPR) equipment. Hybrid MPDT was devised to
minimize the risk of SARS-CoV-2 transmission during and immediately
after tracheostomy. The hybrid MPDT technique means a combination of
conventional surgical tracheostomy and modified PDT. Initially, a small
skin incision and minimal dissection are performed to access the trachea
as for conventional tracheostomy, and then modified PDT is done using
four instruments in the Ciaglia Blue Rhino Percutaneous Dilatational
Tracheostomy KitⓇ(Cook Critical Care, Bloomington, IN,
USA). In detail, hybrid MPDT requires an initial horizontal minimum skin
incision of < 1 cm in the neck, like conventional open
surgical tracheotomy. Briefly, the trachea is exposed by making a
vertical incision at the fascia center, and then the
2nd or 3rd tracheal cartilage is
exposed. Using a cold knife, a 5 mm long incision is placed in tracheal
membrane without tracheal cartilage resection, and then a hole (the
tracheal window) is opened slightly with a mosquito forceps and the
position of the endotracheal tube (ETT) is checked (Figure 2A). The
location of the ETT tip is confirmed through the tracheal window by
naked eye without using a bronchoscope. When the tip of ETT was not
visible while slowly withdrawing the ETT, the ETT balloon was inflated
to fix its position. A gradual dilator is inserted into the tracheal
window (Figure 2B), and a guide wire is inserted along the dilator
(Figure 2C). The dilator is then removed, and the guide wire left in
place (Figure 2D). The tracheal window is then expanded using a 36Fr
dilator (Figure 2E), and the tracheostomy tube is inserted along the
guide wire, which is then removed (Figure 2F).