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Fig. 10.1  COVID infectivity

Day -5	Day 0	Day 5
Viral	Viral PCR	Viral PCR
Exposure	Detection	Declines

least one more week of ventilation. Patients randomized to the early group were scheduled immediately for tracheostomy. The late group was scheduled after 10 days of mechanical ventilation. Of the 455 patients assigned to early tracheostomy, 91.9% received a tracheostomy and of the 454 assigned to late tracheostomy, 44.9% received a tracheostomy. There were no differences in the primary end point of 30-day all-­cause mortality or other outcomes including critical care unit length of stay or 2-year mortality.

In the early stages of the pandemic, the timing and techniques for tracheostomy were based on the evidence from prior viral pandemics including Middle East Respiratory Syndrome MERS, H1N1, and the severe acute respiratory syndrome (SARS) pandemic of 2003. In the SARS pandemic of 2003, 14–20% of patients required endotracheal intubation and mechanical ventilation [7]. Early case report in the 2003 SARS pandemic demonstrated that tracheostomy could be performed safely with appropriate personal protective equipment, including a water impermeable cap, goggles with an anti-mist screen, N95 mask, plastic transparent full-face shield worn outside goggles and N95 masks, disposable water-impermeable surgical gown, and double surgical gloves and plastic shoe covers. These procedures were performed under apnea and with neuromuscular blockade to prevent coughing or other movement [8].

Previous experience with the SARS outbreak in 2003 led proceduralists to develop tracheostomy protocols that take into account the infectivity of virus-infected patients. Surgical tracheostomy was favored over a percutaneous approach given the potential for aerosolization with disconnections from the ventilator. Early

tracheostomy was recommended against during the SARS outbreak, due to signi cant infectivity during the early acute period, the high mortality in patients who were mechanically ventilated, and the lack of compelling data regarding tracheostomy-­facilitated weaning ef cacy. Despite the lower mortality rate in coronavirus disease 2019 (COVID-19) compared with SARS (2.3% vs. 11%), a similarly high percentage of patients (9.8–15.2%) require invasive mechanical ventilation or extracorporeal membrane oxygenation and thereby placement of tracheostomy [8, 9]. The lessons learned in prior viral pandemics can be used to guide current practice taking into consideration the unique challenges of resource and staf ng allocation as well as the risk of exposure to healthcare workers. In COVID-19, the viral load falls from a peak associated with the onset of symptoms at around day 5 (Fig. 10.1).

Indications and Contraindications

Patient selection and timing of tracheostomy is based on expert guidance and varies based on society. Early in the COVID-19 pandemic, multiple organizations published consensus statements in academic journals to provide direction to their membership. While there was not signi cant variation in patient selection, there was variation in the recommended timing. Organizations did not support proceeding with tracheostomy in patients with multiorgan failure, tenuous respiratory status (such as requiring prone ventilation), the need for cardiovascular support beyond low dose vasopressors, or when the performance of a tracheostomy or the posttracheostomy care put healthcare workers or

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other patients at risk of infection. The Airway and Swallowing Committee of the American Academy of Otolaryngology-Head and Neck Surgery published recommendations in 2020 [10]. They recommended that tracheotomy could be considered in patients with stable pulmonary status but should not take place sooner than 2–3 weeks from intubation and, preferably, with negative COVID-19 testing. They noted that patients who show no clinical or radiological remission within 10 days may be more likely to require ongoing ventilation and many physicians adopted a 21-day policy prior to open surgical tracheostomy based on the mean time from onset to death of 23.7 days in the SARS-1 pandemic [11].

The American Association of Bronchology and Interventional Pulmonology and American College of Chest Physicians recommended tracheostomy in patients with COVID-19 when prolonged ventilator support is anticipated, de ned as anticipated duration of mechanical ventilation of >10–15 days [12]. The lack of COVID-19 tracheostomy-­related evidence, the conficting published data on early vs. late tracheostomy in general, and the general resource allocation issues of COVID led the group to not provide speci c guidance on timing. The AABIP/CHEST does not suggest routine COVID-19 testing prior to the procedure.

The contraindications to tracheostomy noted were largely related to patient risk of death and risk of infectivity. As the procedures are recommended to be performed under apnea, an apnea trial is performed prior to the procedure and as such patients with high requirements for oxygenation or ventilation are not ideal candidates. The usual relative and absolute contraindications also apply. These include high fractional inspired oxygen and positive end expiratory pressure, hemodynamic instability, local controlled infection, proximity to burns/wounds, coagulopathy, dif - cult anatomy, prior neck radiation, and elevated intracranial pressure as relative contraindications. Absolute contraindications include an unstable cervical spine, uncontrolled coagulopathy, and severe local infections of the anterior neck.

Equipment Needed and Modifcations in a Viral Pandemic

Equipment for surgical and percutaneous tracheostomy includes the usual procedure trays or kits as well as additional equipment which functions to reduce aerosolization and protect members of the healthcare team. Personal protective equipment should include a powered air purifying respiratory or water impermeable cap, goggles with an anti-mist screen, N95 mask, and plastic transparent full-face shield worn outside goggles and N95 mask, as well as a disposable water-­ impermeable surgical gown, surgical gloves, and plastic shoe cover. The most experienced and smallest team, ideally the proceduralist, bronchoscopist, and a respiratory therapist, is recommended and medication considerations include the use of neuromuscular blockade to minimize the cough refex and aerosol generation.

For elective surgical tracheostomy, a tracheostomy set of instruments is required. For emergency tracheostomy, a cricothyroidotomy and a separate tracheostomy set are required. There is a recommendation to rely on cold instrumentation and avoid monopolar electrocautery as able. A cuffed, non-fenestrated tracheostomy tube should be placed and a heat moister exchanger (HME) with viral lter or a ventilator lter should be placed in the ventilator circuit.

The consensus statement of the AABIP/ CHEST recommended additional supplies for percutaneous tracheostomy beyond the usual percutaneous tracheostomy kit. This kit generally includes a surgical scalpel blade, an introducer needle, a guidewire, a small tracheal dilator, a single-stage progressive tracheal dilator, a tracheal loading dilator, and a small slip-tip syringe (Fig. 10.2). They recommend consideration of packing of the oropharynx such as with kerlix and the use gauze or a sponge at the stoma site to further reduce aerosols. The use of a disposable video bronchoscope was also recommended. Ultrasound could also be used as an adjunct to identify anatomic landmarks and to evaluate vascular structures prior to the procedure.

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Fig. 10.2  Cook punch dilator, single-step dilator, and loading dilators

Procedural Technique and Modifcations

A tracheostomy can be created with an open surgical or a percutaneous dilation technique and can take place in an operating room or at the patient’s bedside, with a percutaneous approach having the bene t of being performed at the bedside and minimizing transportation of the patient. The open technique involves dissection of the anterior pretracheal tissue and insertion of a tracheostomy tube under direct visualization. The percutaneous technique is performed with the use of a modi ed Seldinger technique and bronchoscopic guidance.

For percutaneous tracheostomy, the team should perform the standard time out to verify the patient details and procedure to be performed. Modi cations to the technique should be addressed at this time is members of the team are unfamiliar. This should be performed outside the room, if possible, to minimize personnel in the room. The nurse should administer additional sedation if needed after the time out is performed and once the desired sedation level is reached, administer a short-acting neuromuscular blocker. The nurse should remain immediately available outside the patient’s room for the duration of the procedure.

After patient positioning and identi cation of anatomic landmarks, the anterior neck is prepped and draped [13]. At this time, the respiratory therapist induces apnea and the ventilator circuit is disconnected from the endotracheal tube to insert a bronchoscope adapter and allow insertion of the

fexible bronchoscope. Ventilation can now be resumed and an inspection of the airways performed. If packing of the oropharynx is pursued, it can be performed with moist kerlix at this time. The bronchoscope is then positioned at the distal aspect of the endotracheal tube. Apnea is again induced, the cuff is defated, and the bronchoscopist and respiratory therapist withdraw the endotracheal tube to the subglottic level under direct visualization and the cuff is infated. Local anesthesia is performed in the eld using 1% lidocaine with epinephrine.

The proceduralist can now proceed with the tracheostomy using a Seldinger technique. The introducer needle is inserted between the second and third tracheal ring at the midline. With the bevel of the needle directed downward, the guidewire is now inserted via the needle into the distal trachea and advanced just beyond the main carina. The introducer needle is withdrawn and a 2–3 cm incision (vertical or horizontal) is made. The small tracheal punch dilator is now inserted over the guidewire and withdrawn leaving the guidewire in place. The single-stage dilator with the protective sheath is now loaded over the wire and the dilation is performed. The progressive dilator is removed and the tracheostomy tube with the loading dilator is advanced over the guidewire and protective sheath. Once the tracheostomy tube is positioned within the airway, the loading dilator, protective sheath, and guidewire can be removed. To minimize aerosolization, apnea can be induced from the time the punch dilation is performed until infation of the tracheostomy cuff and wet gauze can be placed over the stoma to minimize any potential leak. The tracheostomy tube can be connected to the ventilator circuit, the cuff infated, and ventilation resumed if a period of apnea was used. The tracheostomy tube can now be secured with sutures and a tracheostomy collar.

A modi ed approach to the percutaneous technique was described early in the pandemic by faculty at New York University [14]. They utilized a side-by-side technique whereby they placed the bronchoscope alongside the endotracheal tube, not inside it. This allowed visualization during the procedure as well as continued

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standard mechanical ventilation with the cuff infated after positioning the endotracheal tube cuff in the distal trachea (Figs. 10.3 and 10.4). This technique mitigates the risk of virus aerosolization during the procedure.

For open surgical tracheostomy, anatomic landmarks are palpated and marked. The surgicaleld is then prepped and draped. Under a period of apnea, the existing endotracheal tube is advanced distal to the desired surgical site and the cuff is infated. Apnea is maintained as tolerated while incising the trachea. A 1–2 cm vertical or horizontal incision is made inferior to the cricoid cartilage. The incision is extended through the platysma muscle to expose the strap muscles

Fig. 10.3  Exploratory tracheocentesis with modi ed technique

Fig. 10.4  Single-step dilator with modi ed technique

(sternohyoid and sternothyroid), identifying the median raphe. The strap muscles are then retracted laterally, exposing the cricoid cartilage and thyroid gland. The thyroid isthmus is identi-ed and ligated, if necessary, depending on its location along the trachea. Hemostats can be utilized to cross-clamp the isthmus, subsequently oversewing each stump with a silk suture to ensure hemostasis of thyroid tissue. A cricoid hook is then placed under the cricoid cartilage to elevate the larynx and trachea into the operativeeld. The second and third tracheal rings are identi ed. An incision is made between the second and third rings, and the tracheostomy tube is placed. The tracheostomy tube is then connected to the circuit and the cricoid hook is released. The tracheostomy tube is now secured to the anterior neck and a soft or hard tracheostomy collar is placed.

A group of otolaryngologists in the United Kingdom described additional techniques to minimize aerosolization [15]. They describe clamping the endotracheal tube at two to three points in the procedure, with the tube clamped when advancing into the distal trachea beyond the proposed tracheal window, when the tube is withdrawn proximal to the tracheal window to allow insertion of the tracheostomy tube, and with the endotracheal tube remaining clamped as tolerated until the conclusion of the procedure. Various modi cations in the standard surgical technique may also be performed including stay ligature placement laterally to provide traction for tube placement and additional post-operative security, removal of an anterior cartilage window, or the creation of a Bjork fap (an inferiorly based cartilage fap is created and secured to the subcutaneous tissues) [16].

In the post-operative period, cuff leak and cuff pressures should be assessed regularly and the cuff should be maintained appropriately infated. Circuit disconnections should be avoided and suctioning should be performed via a closed circuit. Defation of the cuff, replacement of the tracheostomy tube, and initiation of a plan for decannulation should be deferred until the patient is known to be COVID-19 negative.

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