An uncomplicated and safe technique for preventing endotracheal tube cuff damage during tracheostomy using pressure-controlled ventilation: the PCV method

The coronavirus is spread primarily via respiratory droplets and close or direct contact. Aerosol propagation is also possible through prolonged exposure to high concentrations of infected aerosols in a relatively closed environment.1 According to recently reported data, at least 10% of patients with coronavirus disease (COVID-19) required hospitalization in critical care units, and approximately 3% required mechanical ventilation through an endotracheal tube (ETT) during the course of illness.2,3 Many patients who require mechanical ventilation will later need to undergo tracheostomy. Tracheostomy is associated with an increased production of aerosols and a higher risk of viral transmission to healthcare personnel.4 Herein, we describe a safe technique for tracheostomy that is applicable for patients with COVID-19, with an emphasis on the safety of both the patient and the medical team involved.5 We have termed this technique the “pressure-controlled ventilation” (PCV) method.

From the perspective of aerosol prevention, tracheostomy is better performed after intubation under general anesthesia than in an awake patient with spontaneous breathing. The most frequent complication during a tracheostomy procedure is ETT cuff damage when the trachea is incised; this can result in ventilation difficulty and infectious aerosol dissemination. One way to prevent ETT cuff damage is to ensure that the cuff is in an optimal position—distal to the sternal notch (away from the tracheostomy incision point) but above the tracheal carina. The ETT cuff position can sometimes be confirmed by tracheal palpation; however, the relevant anterior neck structures are not always easily palpable. Moreover, if the ETT is advanced too deeply, there is a risk of endobronchial ventilation. Lastly, neck extension during tracheostomy positioning can easily move the ETT proximal to the sternal notch. As there are no reliable methods to protect the ETT cuff from damage during tracheostomy, we developed the PCV method.

The PCV method is used after performing normal intubation under general anesthesia. The ventilator is set to “pressure-controlled” mode and the patient’s spontaneous breathing is temporarily suppressed using opioids or neuromuscular blocking agents. The tidal volume (V_T) is checked. Next, the anesthesiologist advances the ETT until the V_T decreases (by one-third to one-half) indicating that the ETT has been advanced into an endobronchial position. Once this point is reached, the ETT is slowly withdrawn until the V_T returns to the original volume (i.e., to a position above the carina). The ETT is then secured and the tracheotomy can proceed.

In our experience, the PCV method significantly reduces the probability of ETT cuff damage and thus reduces potential aerosol generation, prevents ventilation and oxygenation difficulties if the ETT cuff is damaged, and renders the surgical procedure less difficult. Its use can theoretically reduce the risk of COVID-19 infection for respiratory care personnel, anesthesiologists, and tracheostomy surgeons.