Indian Journal of Otology

: 2020  |  Volume : 26  |  Issue : 3  |  Page : 179--181

Mastoid surgery during coronavirus disease 2019 pandemic: Focusing on mitigation measures

Kripa Dongol, Rabindra Bhakta Pradhananga, Pabina Rayamajhi, Urmila Gurung 
 Department of ENT, Institute of Medicine, Kathmandu, Nepal

Correspondence Address:
Dr. Kripa Dongol
Department of ENT, Institute of Medicine, Kathmandu


Mastoid surgery is an aerosol-generating procedure and is considered as high-risk procedure during this pandemic of coronavirus disease. It should, however, be performed in certain life-threatening conditions. Otorhinolaryngologists should be well versed with the measures to protect ourselves from acquiring the coronavirus. We, therefore, report a case of mastoidectomy performed during this pandemic for an intracranial complication of chronic otitis media, focusing on the mitigation measures.

How to cite this article:
Dongol K, Pradhananga RB, Rayamajhi P, Gurung U. Mastoid surgery during coronavirus disease 2019 pandemic: Focusing on mitigation measures.Indian J Otol 2020;26:179-181

How to cite this URL:
Dongol K, Pradhananga RB, Rayamajhi P, Gurung U. Mastoid surgery during coronavirus disease 2019 pandemic: Focusing on mitigation measures. Indian J Otol [serial online] 2020 [cited 2021 Feb 25 ];26:179-181
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Full Text


Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2.[1] The initial cases occurred in Wuhan, China, in December 2019.[2] It was declared pandemic by the World Health Organization on March 11, 2020.[3] Viral transmission occurs via droplets, aerosols, or fomites. Otorhinolaryngologists are at higher risk of COVID-19. They deal with upper airway which harbors high concentration of the corona virus.[4] The middle ear, mastoid, and the eustachian tube are contiguous with the nasopharynx. There is presence of different viruses both in the nasopharynx and middle ear in patients with acute otitis media.[5]

During drilling of mastoid, there is significant aerosolization of bone and other tissues.[6] The virus particles can remain in air, thereby forming a risk to the surgeon and other staffs. The objective of this study is to describe the measures that could mitigate the risk of virus transmission during mastoid surgery.

 Case Report

A 56-year-old male was diagnosed with left chronic otitis media with cholesteatoma with meningitis in May, 2020. Informed consent was taken from the patient. He hailed from hilly region of the country where no case of coronavirus had been reported. The patient had received 2-week course of intravenous antibiotics following which his general condition had improved and he was planned for canal wall down mastoidectomy. During hospital stay, there were no clinical features suggestive of COVID-19. The coronavirus test was not performed prior to the surgery as per the hospital guidelines available till that date. However, different measures were used to reduce the burden of virus, had that case been positive for coronavirus.

Intubation was performed by the senior anesthesiologist with one resident doctor and one anesthesia assistant, taking precautions as per their protocol for COVID-19. Mastoidectomy was performed by the senior surgeon with only few staffs accompanying him in the operating room. Personal protective equipment (PPE), double masks (N95 with surgical mask over it), double gloves, goggles, and head cover were worn by the surgeon and the scrub assistant. Routine cleaning and draping of the surgical site were performed.

Microscope was draped with Steri-Drape, creating two holes in it to fit the forearms of the operating surgeon and one end of its perimeter was fixed to the lens with adhesive tape. This draping was done in order to reduce the aerosol of bone dust. Incision of the postauricular skin and raising the anteriorly based flap was performed using a microscope with 0.4 magnification. Other parts of the surgery were completed with 0.6 and 1 magnification. The drilling was performed with 35,000 rpm with irrigation. Effective central suction was used to reduce aerosolization. Minimal use of cautery was done as cautery also generates aerosol. After completion of the surgery, the Steri-Drape was carefully unfastened from the microscope and disposal was done as per the hospital protocol.


Otorhinolaryngologists may be susceptible to get infection with coronavirus because they have to deal with areas having high viral load. Many patients visiting the hospital may be asymptomatic carrier. Most symptoms of COVID-19 mimics any other viral infection, so ENT may be the first specialty which the patient visits. ENT examination may induce sneezing, gagging, and coughing that cause droplet and aerosol transmission of the virus. Procedures such as nasopharyngolaryngoscopy, nasal packing for epistaxis, endonasal surgery, tracheostomy, bronchoscopy, CO2 laser ablation, electrocautery, and mastoid drilling are considered to be aerosol-generating medical procedures.[7] Methods to mitigate the risk with these procedures must be formulated to reduce viral transmission to self and to others.

The viral load is high in upper and lower airways. A study by Pitkäranta et al. identified that viral RNA could be found in middle ear fluid samples collected from children with an upper respiratory illness and acute otitis media when assessing for coronavirus, respiratory syncytial virus, and human rhinovirus.[8] However, viral RNA has also been detected in the blood of asymptomatic and symptomatic patients of coronavirus. Hence, inhaled aerosol of blood may also be a source of infection.[9]

Surgical procedures using electrocautery and high-speed microdrills are aerosol-generating medical procedures.[7] Use of electro cautery may generate viral plume.[7] High-speed drills are believed to produce bony particulates <5 μm in size.[6] Diamond burr has been shown to generate more respirable particles than cutting burr in a study by Saternus and Kernbach–Wighton.[9] Lannigan et al. found that the radius of spray during dissection with high-speed drill was 41 cm.[10] A study done by Hilal et al. have found the bone dust in the cornea of fish during otologic procedure and had concluded that the bone dust may be the vector of disease transmission.[11]

According to the guidelines given by the British Otologic Society, mastoidectomy should be avoided during COVID-19 pandemic unless there is a life-threatening condition like intracranial complication of otitis media as in this case.[12] Waiting for 2 weeks prior to mastoidectomy had two advantages in this case: the first one being monitoring of symptoms of COVID-19 and reduction of viral load had the case been coronavirus infected and the second one being improvement of general well-being of the patient suffering from meningitis. As the patient came from the area where no case of coronavirus had been reported and also due to lack of test kit, the protocol of the hospital was not to test for coronavirus at that point of time. However, as community transmission has been recently detected in our country, now, the protocol has been changed to test every case for coronavirus prior to surgery.

Mastoidectomy was performed by a well-experienced senior surgeon to reduce the number of operating room members and to reduce the total duration of drilling and surgical time. The most important part of the surgery was draping the microscope with the aim of reducing the amount of aerosol that gets generated during mastoid drilling. The draping is easy, less time-consuming, and very effective way to mitigate aerosol. Two holes in the Steri-Drape were created to adjust the forearms of the surgeon. In this procedure, all the steps of the surgery were completed using the microscope. If the surgeon is uncomfortable to do the soft tissue part under microscopic guidance, the draping could be performed at least for the drilling part. Transparent drape would be more easier for visibility of surgical field for the assistants. Further improvement can be done by adding one more drape between surgical site and anesthesiologist.[13] At the end of the surgery, the drape should be removed carefully to prevent dislodgement and reaerosolization of the particles.[13] Some of the guidelines have recommended the use of gouge and hammer to remove the bone during mastoidectomy.[14]

A study done by Chen et al. in fresh frozen cadaveric heads with fluorescein solution in the mastoid air cells showed that even a simple barrier drape reduced significant particulate dispersion. The barrier drape contained most of the bone dust and there was significant reduction of bone dust particles beyond 30 cm.[13] Heller W, Mitchell T, and Thomas S have described the technique of microscope draping using two drapes for aerosol reduction during mastoidectomy.[15]

Use of electrocautery should be kept to minimum to reduce aerosolization. Cautery should be used at low power and a powerful suction can be kept nearby to suck out the plume. Draping the surgical site as in this case significantly reduces the aerosolization of electrocautery. Unfenestrated suction must be used as the fenestra of microsuction may be the source of aerosol generation.[12] Central suction is preferred over portable suction. The operating room should preferably be negative pressure room with high-efficiency particulate air filtration to prevent airborne virus spreading into adjacent areas.[16]

The compiled recommendation for otologic procedure during COVID-19 pandemic given by Saadi et al. states the use of enhanced PPE.[14] The enhanced PPE includes N95 respirator and eye protection or powered air-purifying respirator (PAPR), disposable cap, disposable gown, and gloves. Airtight eye protection or full face shield is recommended if PAPR is unavailable.[14] Surgical masks have been shown to be ineffective in preventing inhalation of bone dust particles. N95 respirator was found to significantly reduce the particulate exposure.[6]

The limitation of this study is description of experience of only a single case of mastoid surgery. Further improvements of draping technique of the microscope are expected with more practice. Studies regarding presence of viral particles in the aerosol may be conducted if surgery is to be performed in a coronavirus disease (COVID) case.


Mastoid surgery using high-speed drill is aerosol-generating procedure with high risk of viral transmission to the health-care providers. Otorhinolaryngologists should be aware of various methods to mitigate the risk of COVID when performing mastoidectomy.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.


Dr. Bibek Basukala and Dr. Poonam Aggrawal for technical support.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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