Current Otorhinolaryngology COVID-19 Literature Review

Otolaryngologic Procedures and COVID-19
As the COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 continues to escalate in the United States and elsewhere, we are faced with developing methods to provide care to our patients while also keeping them, our co-workers, and ourselves safe. Much of the information available to date is anecdotal and is evolving as the pandemic continues, however, it would be imprudent not to use what data is available and learn from the experiences of countries such as China and Italy where the virus has been spreading longer.

Healthcare workers are at increased risk of exposure to and infection by the virus, and there is mounting evidence that otolaryngologists are one of the highest risk categories among doctors and healthcare workers.1,2 SARS-CoV-2 can be detected on swabs from the throat and particularly the nose of both symptomatic and asymptomatic patients3, and researchers have shown stability of the virus on surfaces for up to 72 hours and remaining in the air for at least 3 hours if not longer.4 It has also been found in the lung and oropharynx.5 Procedures that involve instrumentation of the upper airway including the nose, oral cavity, pharynx, larynx, and trachea have the risk of aerosolizing particles.5 When aerosolized, the virus has been demonstrated to spread and contaminate multiple surfaces including that air exhaust vents that circulate air.6,7 In one case of endoscopic transnasal pituitary surgery in China, all 14 individuals who entered the operating room during the procedure later became infected, highlighting the potentially high infectivity associated with upper airway procedures, potentially owing to a higher viral load experienced in this type of exposure compared to a community exposure.1

If we compare the Covid-19 (SARS-CoV-2) nosocomial data to that of the SARS epidemic (SARS-CoV-1) of 2003, we saw that over 20% of those infected were medical personnel.8 For Covid-19, data from Lombardy (Italy) shows that 10% of all physicians and nurses tested positive in early March.9 In Wuhan, a case series of 138 patients at an academic hospital showed an infection rate of 29% of medical staff.10 Indeed, thousands of doctors have been infected in Wuhan and otolaryngologists have been reported to infected at higher rates than others.11

We do, however, still have an obligation to perform urgent and emergent cases in the interest of our patients for life-threatening situations or diseases, such as cancer, where failure to act will lead to high morbidity or eventual mortality. It is known that cancer patients are susceptible to infection – early data from China showed that among patients with Covid-19, there is a ~3 fold higher proportion with cancer than the incidence of cancer in the general population and that these patients did poorer in disease recovery.12 The CMS recently developed recommendations to assist with determining which cases should be deferred and which should not.13 We are struck, then, with finding a balance between providing essential treatment to our patients who need it while not placing ourselves and our hospital teams at unnecessary risk.

Although initial reports of asymptomatic carriers from Chinese data were low, it appears that up to 1/3 of patients who test positive may be asymptomatic.1,14,15 At this point, the majority of patients being tested in the US are symptomatic, meaning that there is likely a potentially large subset of sub-clinically infected individuals who may wind up on our operating room tables, placing our surgical teams at risk. Asymptomatic patients have been found to spread Covid-19 with high efficiency even when providers use conventional protection (face masks).1 There are reports of young healthy patients infected with Covid-19 being completely asymptomatic but still demonstrating visible ground-glass changes on radiography1,16 – suggesting that instrumenting the airway of an otherwise young, healthy and asymptomatic patient could aerosolize virus. In addition, while facemasks may protect non-respiratory mucosal surface, there is evidence that the virus can spread to health care workers through non-respiratory mucosal surfaces which was exemplified in the report of one worker exhibiting conjunctivitis before progressing to catarrhal symptoms and fever.1,17

Many centers have moved towards pre-operative screening of asymptomatic patients 48 hours prior to undergoing any aerosol generating procedure (airway procedures including laryngoscopy, nasal or sinus surgery, head and neck mucosal surgery, mastoid surgery) and even routine intubation – so all patients undergoing ay procedure under general anesthesia should be screened.6,18–20 Indeed, the American Academy of Otolaryngology – Head & Neck Surgery developed a statement in response to the CMS guidelines, stating “unless emergent, surgical procedures should only be undertaken after ascertaining the COVID-19 status and then performed using either

N95 respirator masks with either goggles or a faceshield or PAPR.”21 Likewise the CDC and WHO recommend that health care workers wear a gown, gloves, goggles and a medical mask that protects against droplet-based transmission, and that once supply chains are restored the CDC recommends N95 masks specifically.22,23 The Chinese Society of Anesthesiology, The National University Health System of Singapore and the Stanford University guidelines however recommend using PAPR hood when available for high risk procedures including intubations.24,25

Of note, respiratory viruses have been found to contaminate 10.2% of the outer surfaces of medical masks even in a non-outbreak context26, we can therefore imagine viable virus particles on the mask surface that could contaminate the user when reapplying the mask if it is removed to be reused later (especially given the known 3 day surface stability4). The Dutch National Institute for Public Health carried out a study showing that sterilization of marks can successfully be performed with aerosolized hydrogen peroxide without deforming the mask or affecting its fit,27 which could be a better method of mask reuse.

1. Chang D, Xu H, Rebaza A, Sharma L, Dela Cruz CS. Protecting health-care workers from subclinical coronavirus infection. Lancet Respir Med. 2020;8(3):e13. doi:10.1016/S2213-2600(20)30066-7

2. 2. RT. Why Surgeons Don’t Want to Operate Right Now. Bloomberg News. Published March 24, 2020.

3. Zou L, Ruan F, Huang M, et al. SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients. N Engl J Med. 2020;382(12):1177-1179. doi:10.1056/NEJMc2001737

4. van Doremalen N, Bushmaker T, Morris DH, et al. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. N Engl J Med. March 2020. doi:10.1056/NEJMc2004973

5. Lu D, Wang H, Yu R, Yang H, Zhao Y. Integrated infection control strategy to minimize nosocomial infection of coronavirus disease 2019 among ENT healthcare workers. J Hosp Infect. February 2020. doi:10.1016/j.jhin.2020.02.018

6. Vukkadala N, Qian ZJ, Holsinger FC, Patel ZM, Rosenthal E. COVID-19 and the otolaryngologist – preliminary evidence-based review. Laryngoscope. March 2020. doi:10.1002/lary.28672

7. Ong SWX, Tan YK, Chia PY, et al. Air, Surface Environmental, and Personal Protective Equipment Contamination by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) From a Symptomatic Patient. JAMA. March 2020. doi:10.1001/jama.2020.3227

8. Ho P-L, Tang X-P, Seto W-H. SARS: hospital infection control and admission strategies. Respirology. 2003;8 Suppl:S41-45. doi:10.1046/j.1440-1843.2003.00523.x

9. Thomas-Rüddel D, Winning J, Dickmann P, et al. Coronavirus disease 2019 (COVID-19): update for anesthesiologists and intensivists March 2020. Anaesthesist. March 2020. doi:10.1007/s00101-020-00760-3

10. Wang D, Hu B, Hu C, et al. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. JAMA. February 2020. doi:10.1001/jama.2020.1585

11. Europe’s Doctors Repeat Errors Made in Wuhan, China Medics Say. Bloomberg News. March 17, 2020.

12. Liang W, Guan W, Chen R, et al. Cancer patients in SARS-CoV-2 infection: a nationwide analysis in China. Lancet Oncol. 2020;21(3):335-337. doi:10.1016/S1470-2045(20)30096-6

13. CMS Adult Elective Surgery and Procedures Recommendations. Published March 18, 2020.

14. Nishiura H, Kobayashi T, Suzuki A, et al. Estimation of the asymptomatic ratio of novel coronavirus infections (COVID-19). Int J Infect Dis. March 2020. doi:10.1016/j.ijid.2020.03.020

15. 7. MJ Lew L, Jeong-ho L. A third of coronavirus cases may be ‘silent carriers,’ classified Chinese data suggests. South China Morning Post. Published March 22, 2020.

16. Chan JF-W, Yuan S, Kok K-H, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet. 2020;395(10223):514-523. doi:10.1016/S0140-6736(20)30154-9

17. Alice Yan. Chinese expert who came down with Wuhan coronavirus after saying it was controllable thinks he was infected through his eyes. South China Morning Post. Published January 23, 2020.

18. Guidance for Health Care Workers Performing Aerosol Generating Medical Procedures during the COVID-19 Pandemic. CSO-HNS Executive Committee. March 26, 2020.

19. Guidance for ENT surgeons during the COVID-19 pandemic. Australian Society of Otolaryngology. March 20, 2020.

20. Otolaryngologists May Contract COVID-19 During Surgery. ENT Today: Triologic Society. Published March 20, 2020.

21. AAO-HNS Responds to CMS Statement on Adult Elective Surgery and Procedures Recommendations. American Academy of Otolaryngology – Head & Neck Surgery. Published March 26, 2020.

22. Rational Use of Personal Protective Equipment for Coronavirus Disease 2019 (COVID-19). World Health Organization. 2020.1-eng.pdf. Published 2020.

23. Interim Infection Prevention and Control Recommendations for Patients with Suspected or Confirmed Coronavirus Disease 2019 (COVID-19) in Healthcare Settings. Centers for Disease Control. 2020. recommendations.html.

24. Zuo M, Huang Y, Ma W, et al. Expert Recommendations for Tracheal Intubation in Critically ill Patients with Noval Coronavirus Disease 2019. cmsj. 2020;0(0):0. doi:10.24920/003724

25. Ti LK, Ang LS, Foong TW, Ng BSW. What we do when a COVID-19 patient needs an operation: operating room preparation and guidance. Can J Anesth/J Can Anesth. March 2020. doi:10.1007/s12630-020-01617-4

26. Chughtai AA, Stelzer-Braid S, Rawlinson W, et al. Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers. BMC Infect Dis. 2019;19(1):491. doi:10.1186/s12879-019-4109-x

27. Reuse of FFP2 masks. Dutch National Institute for Public Health and the Environment. Published March 18, 2020.