Disclaimer: We aim to present letters from our readership that may generate further discussion on managing patients with COVID-19. Given the novelty of COVID-19, best-available clinical evidence is limited and supported from anecdotal reports from China, South Korea, Italy and other sites, and from studies of previous epidemics like SARS and MERS. The opinions expressed are those of the authors and not the APSF. These materials are presented for informational and educational purposes only and do not establish a standard of care or constitute medical or legal advice. The APSF does not support or endorse any specific idea, product, equipment, or trademarked technique. We strongly promote consistency with your governing bodies and organizations such as the CDC, WHO, ASA, AANA, and AAAA. Readers are reminded to consult with their institutions and medical/legal advisors regarding any of the views and opinions expressed by the authors.
In the midst of the COVID-19 pandemic, anesthesia providers, intensive care unit and emergency room staff, and other health care workers (HCW’s) often find themselves in close proximity to patients’ airways. In many geographic areas in the US and worldwide, there is a shortage of the ideal recommended personal protective equipment (PPE), such as N-95 masks or powered air-purifying respirators (PAPR’s), and face shields, or use of sub-optimal PPE (such as standard surgical facemasks instead of N-95 masks or PAPR’s). In spite of probable high prevalence of often-undiagnosed COVID-19 due to community spread and a lack of widespread testing, HCW’s are therefore simply unable to employ optimal “Universal Precautions” measures for COVID-19 in the manner used for less prevalent infectious diseases such as hepatitis and HIV. The risk to HCW’s is greatest when performing, or assisting with, potentially aerosol-producing procedures such as endotracheal intubation and extubation, during and after which, in spite of our best efforts, patients often cough and thereby widely spread the expelled cloud of potentially contagious aerosol.
This situation is producing justifiable concern, anxiety, depression, helplessness, and even fear amongst HCW’s responsible for performing these vital airway management procedures in close proximity to the patients’ airways. Many constructive, creative suggestions have been proposed, including rapid sequence intubations without mask ventilation after induction, adequate depth of anesthesia and neuromuscular blockade, performing intubations in negative pressure rooms (although most operating rooms are positive pressure unless specifically made negative pressure), covering patients’ upper torsos and faces with clear plastic drapes, or with clear “intubation boxes” with holes cut into them to allow insertion of the airway manager’s hands. All of these approaches have their own limitations.
A very useful additional tool, however, may already exist in many operating rooms: surgical smoke evacuators (SSE’s).1,2 SSE’s have been in use for decades. They are powerful negative pressure pump-and-filter devices placed near the surgical field to efficiently suction and remove the plume of smoke generated by surgical electrocauteries and lasers. SSE’s are often used by plastic surgeons, otorhinolaryngologists, urologists, and gynecologists during excision of warts, since the plume from these procedures has been demonstrated to carry viable human papillomavirus particles. They are also often used by general surgeons during laparoscopic procedures to clear the smoke from the endoscopy field to improve vision.
Many SSE’s employ ULPA (Ultra Low Particulate Air) filters, which are even more efficient than HEPA (High Efficiency Particulate Air) filters. ULPA’s filter 0.1 micron particles with a greater than 99.9999% efficiency (the COVID-19 coronavirus is approximately 0.125 microns in diameter and a somewhat larger particle when part of an aerosol and combined with water molecules).
Many SSE units can run for many hours without a filter change, and have alarms that indicate when the filter needs to be changed. In the U.S., these are Food and Drug Administration (FDA) approved devices.
A surgical smoke evacuator may be of use in reducing the risk of exposure of HCW’s to aerosolized COVID-19 during airway management by simply holding the end of the SSE air suctioning tubing near the patient’s face and airway until intubation is accomplished, and then again peri-extubation (until patient has a satisfactory unassisted airway and all coughing has ceased).
Most SSE units are portable, and thus can potentially be quickly surface decontaminated, disposable tubing changed, and moved from one operating room to another for intubation and extubation. An SSE can even be stationed in other hospital units, such as the Emergency Room, or designated COVID-19 unit or floor, where intubations and extubations are frequently performed. A SSE should have a minimum flow rate of 25 cu ft/minute.2
As such, Surgical Smoke Evacuators might represent a useful, readily available, relatively unobtrusive supplement or complement to almost any airway management device, technique, or protocol. Where available it can be an additional layer of PPE. If used routinely or selectively, it might add to the protection of HCW’s from aerosol-borne pathogens such as COVID-19, and allow us to move use of SSEs to becoming a routine “Universal Precaution” approach to airborne and aerosol-borne pathogens.
Rene’ Miguel Gonzalez, M.D. is a Staff Anesthesiologist at Hackensack Meridian Southern Ocean Medical Center
Disclosure: The author has no conflicts of interest pertaining to this article.
References
- Katoch S, Mysore V. Surgical smoke in dermatology: its hazards and management. J Cutan Aesthet Surg. 2019;12:1-7.
- AORN. Guideline summary: surgical smoke safety. AORN J. 2017;105:498-500.