Operating on patients with COVID-19
In preparation for the COVID-19 pandemic, Wong et al.39 reviewed operating room (OR) outbreak response measures. Several recommendations can be implemented worldwide, others must be adapted according to the resource availability. An OR with a negative pressure environment is ideal to reduce dissemination of the virus. A high frequency of air changes (25 per hour) reduces viral load within the OR.  Separate ORs can be designated for surgery in patients suspected or confirmed to have COVID-19. Each OR must have its own ventilation system with an integrated high-efficiency particulate air (HEPA) filter. These ORs should be separated from the main OR complex to reduce the risk of contaminating other ORs. Traffic and flow of contaminated air can be minimized by locking all doors to the OR during surgery, with only one possible route for entry and exit.  It is considered important to have a program for the use of PPE. All healthcare personnel must be trained in the use of PPE. Postoperative visits must be suspended and replaced by phone calls to reduce movement of staff around the hospital.
Ti et al.40 recommend that an OR with a negative pressure environment with separate access must be used to operate suspected or confirmed cases of COVID-19 infection. They also advocate that the same room and the same anesthesia machine should be used for all COVID-19 patients during the epidemic. During the surgical procedure a runner wearing PPE is stationed outside the OR in case other drugs or equipment are needed.
The current recommendations of the American Academy of Otolaryngology-Head and Neck Surgery is that all elective surgical treatments should be rescheduled, but it is unavoidable to provide surgical care to patients with time-sensitive, urgent or emergent medical conditions (https://www.entnet.org/content/coronavirus-disease-2019-resources). 41 Many of these patients have cancer, are older, have nutritional problems, comorbid conditions and some have undergone radiation and chemotherapy with possible depressed immunity.42 To date there is insufficient information on the effect of COVID-19  in cancer patients.
No reported series of patients who underwent emergency head and neck surgery exist till date. Hence, one must extrapolate from the experience in other areas to develop a strategy for patients with head and neck cancer requiring emergency surgery. According to Chen et al.43, the National Health Commission of China recommends collecting nasopharyngeal swab samples to test for COVID-19 and have a chest computed tomography (CT) for all pregnant infected patients. Patients must be transferred between the isolation ward and the OR by a negative pressure isolation transfer cabin. All the personnel involved must wear level 3 protective medical equipment (BSL-3). A negative pressure operating room must be used and its preparation and personal protection include the use of BSL-3 (N95 masks, goggles, protective suits, disposable medical caps and rubber gloves). Medical personnel should enter and exit the operating room in accordance with the principles of clean area, contaminated pollution area, and two buffer zones. Designated nurses must ensure the implementation of standard procedures.43 For those who receive general anesthesia, endotracheal intubation and PAPR are mandatory.44
Chen et al.43 used rapid inhalation (2 minutes) induction of general anesthesia  (8% sevoflurane in 100% oxygen) followed by intravenous injections of 2% lidocaine (1–1.5 mg/kg), remifentanil (1–2 mg/kg) and succinylcholine choline (1–2 mg/kg) to ensure optimal intubating conditions. All the patients included in their study were parturients and sevoflurane was used to maintain anesthesia before delivery, with sufentanil (0.25–0.35 µg/kg) and an infusion of propofol (50–100 µg/kg/min) used to maintain anesthesia after delivery.
After the surgical procedure, the anesthesia workstation was disinfected for two hours with an anesthesia circuit sterilizer (containing 12% hydrogen peroxide). Chlorine-containing disinfectant (2,000 mg/L) was used to clean the OR floor and wipe the surface of all reusable medical equipment. All medical devices, such as surgical instruments, were soaked for 30 min in 2,000 mg/L chlorine-containing disinfectant, then sealed and collected into double-layer disposable medical waste bags in the cleaning room and sent to the designated disinfection area. After the OR was cleaned, the air purification system was shut down after 30 min of continuous operation of negative pressure laminar flow. Then, an ultra-low volume of 3% hydrogen peroxide (20–30 mL/m) was used to closed fumigate the OR for two hours. Finally, the negative pressure ventilation of the OR was turned on again.  All medical staff who were involved in surgical procedure were required to have a SARS-CoV-2 virus detection test (RT-PCR of nasopharyngeal swabs) and CT scans once every two weeks.43
Surgeons performing endoscopic sinus surgery seem to be at particular risk due to the high concentration of viral particles in the nasopharyngeal region. The most recent Stanford University guidelines advise canceling elective cases. For COVID-positive patients that cannot be rescheduled, use powered air-purifying respirators (PAPR) if at all possible. 16