Airway

LETTER TO EDITOR
Year
: 2020  |  Volume : 3  |  Issue : 2  |  Page : 98--99

Limiting infective aerosols in operating rooms and during transfer within hospital


Nita J Dsouza1, Tasnim Karachiwala2, Snehal Randive2,  
1 Department of Anaesthesia, Ruby Hall Clinic, Pune, Maharashtra, India
2 Ruby Hall Clinic, Pune, Maharashtra, India

Correspondence Address:
Dr. Nita J Dsouza
Department of Anaesthesia, Ruby Hall Clinic, 40, Sassoon Road, Bund Garden Road, Pune - 411 001, Maharashtra
India




How to cite this article:
Dsouza NJ, Karachiwala T, Randive S. Limiting infective aerosols in operating rooms and during transfer within hospital.Airway 2020;3:98-99


How to cite this URL:
Dsouza NJ, Karachiwala T, Randive S. Limiting infective aerosols in operating rooms and during transfer within hospital. Airway [serial online] 2020 [cited 2020 Oct 23 ];3:98-99
Available from: https://www.arwy.org/text.asp?2020/3/2/98/293960


Full Text



In the operating room (OR), intubation or extubation would qualify as aerosol-generating procedures which would be a major driver of transmission based on available evidence. The present literature highlights guidelines with regard to managing the airway during the COVID-19 pandemic. Details regarding donning and doffing of protective equipment, as also techniques to contain the airborne spread of infective aerosols, have been described in literature. The air as well as surfaces of objects in COVID-19 wards is widely contaminated by SARS-CoV-2.[1] We suggest a simple way to limit the spread of infective aerosol.

In the OR, aerosol-generating procedures such as intubation or extubation are of utmost concern for the OR staff working around COVID-19 patients due to the inherent risk of droplet infection. Aerosols, droplets and fomites are the main means through which COVID-19 is transmitted when there is an unprotected contact between an infector and infectee.[2] Numerous articles have recently emerged on recommendations and precautions when managing the airway in COVID-19 patients in the ORs and the intensive care units (ICUs).[3],[4],[5] In the current scenario with ORs having preset air exchanges per hour and most not being equipped with negative pressure systems to limit spread, we suggest a simple technique in combination with use of a videolaryngoscope for safely managing the airway.[6]

While literature review on managing the airway emphasises donning of personal protective equipment (PPE), it does not adequately address how to deal with droplet and aerosol generation at the head end in the OR, particularly at intubation and extubation. It should make us wonder whether all the staff in the OR are protected sufficiently when managing the airway. Doctors have become infected by this virus despite donning protective gear. Many anaesthesiology departments have made transparent acrylic box hoods with openings for the hands to facilitate intubation. The dimensions of these rigid hoods would need to be customised according to the build of the patient as they rest upon the operating table and cover the shoulder and neck of the patient. Moreover, the use of these hoods imposes a hindrance in the event of a difficult intubation, use of intubating aids such as a bougie and unhindered application of cricoid pressure. In the near future, customised hoods with sliding panels to accommodate different patient sizes may become available. Simulations done to note the aerosol spread during intubation revealed a wide spread of dye onto the face mask, gloves, anterior surface of PPE and shoes of the laryngoscopist, with contamination of the floor up to a distance of two metres from the head end of the table.[7] Dye studies (though with limitations of not detecting microscopic material) have revealed that macroscopic contamination at intubation was restricted to within the box.[7]

During these times of the COVID-19 pandemic, especially in resource-limited settings, we suggest an alternative of using transparent plastic drapes suspended on two L-shaped bars such as the ones used during breast surgery for axillary dissection [Figure 1]. These L-shaped bars are clamped to the operating tables at the desired height and distance from each other. They are then completely covered with transparent plastic which can be tucked below the patient. The covered hands of the anaesthesiologist who has donned the PPE can be introduced below the plastic drape with a videolaryngoscope (as suggested in various emerging guidelines for COVID-19 intubations) for the benefit of being able to visualise the glottis while maintaining a safe distance from the patient. After securing the airway and confirming by capnography, the drape can remain till extubation (unless the surgical site involves the head, neck and face) where again it will help to contain the droplet spread. If the surgical site happens to be in the upper abdomen, one could still derive benefit by lowering the rod away from the head (sanitising appropriately) and tucking the plastic drape over the upper thorax. Head, neck and face surgeries would benefit by limiting aerosol spread during intubation. The rods could then be removed and sanitised, and the plastic drape reapplied by carefully noting the side that was on the patient side (which could be contaminated) and maintaining the same side to cover the patient just before extubation when it would again help to contain the droplet spread. These plastic drapes can be gradually removed in a well ventilated OR by gathering and wrapping in a manner to keep the inner side less exposed to the OR. The air exchanges in most modular ORs is 30–35 times per hour. This would ensure that the viral load is reduced by up to 99% over a 10–12 min period following the aerosol generating procedure if the recirculated air is passed through air handling units with high efficiency particulate air (HEPA) filters. Once the drape is cautiously removed after extubation, the space that was enclosed will now become a part of the or environment where air exchange is being effected. Literature reports regarding how long the aerosols or droplets remain suspended in the surrounding atmosphere still vary. The drapes could be retained (with some tenting on the transport trolleys) till they reach the designated care units or ICUs and suitably removed by the PPE donning personnel in the unit, thus limiting environmental contamination. Our suggestion would additionally limit quantum of spread of aerosols and be beneficial to PPE-donned personnel and support staff. Simple handy resources may currently help safe practices and minimise the exposure to health workers.{Figure 1}

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

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2World Health Organization. Report of the WHO-China Joint Mission on Coronavirus Disease 2019 (COVID-19). Geneva: World Health Organization; 2020. Available form: https://www. who. int/docs/default-source/coronavirus/whochina-joint-mission-on-covid-19-final-report. [Last accessed on 2020 Aug 05].
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