key: cord-1027427-r7czaekv
authors: Porter, James; Blau, Elliot; Gharagozloo, Farid; Martino, Martin; Cerfolio, Robert; Duvvuri, Umamaheswar; Caceres, Aileen; Badani, Ketan; Bhayani, Sam; Collins, Justin; Coelho, Rafael; Rocco, Bernard; Wiklund, Peter; Nathan, Senthil; Parra‐Davila, Eduardo; Ortiz‐Ortiz, Carlos; Maes, Kris; Dasgupta, Prokar; Patel, Vipul
title: Society of Robotic Surgery Review: Recommendations Regarding the Risk of COVID‐19 Transmission During Minimally Invasive Surgery
date: 2020-05-08
journal: BJU Int
DOI: 10.1111/bju.15105
sha: aeb07536684de70403a864d1827befdae2e9b1c5
doc_id: 1027427
cord_uid: r7czaekv

The COVID‐19 pandemic has created uncertainty regarding the safety and appropriate utilization of minimally invasive surgery (MIS) during this current outbreak. Surgical governing bodies such as Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) and the Royal Colleges of Surgery of Great Britain and Ireland have made statements regarding the possibility of COVID‐19 release into CO2 insufflant during MIS. The basis for this concern is prior evidence in the literature of other viral pathogen release during laparoscopic surgery. The recommendations are correctly based on caution given the lack of understanding of how COVID‐19 compares to other viruses with regard to transmission and presence in CO2 during MIS. In this review we have investigated the available literature on COVID‐19 transmission during MIS, address the implications of current and previously published recommendations and discuss steps to mitigate COVID‐19 transmission during MIS for staff and patient safety.

Surgical governing bodies such as Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) and the Royal College of Surgeons (RCS) have recently made statements regarding the possibility of COVID-19 release into CO2 during minimally invasive surgery (MIS) and the potential risk to the patient and health care team (1, 2). This release of CO2 is one of many potential aerosol generating procedures (AGPs) that occur in the operating room. The basis for this concern is prior evidence in the literature of virus release during laparoscopic surgery. The recommendations by these organizations have erred on the side of caution given the lack of understanding of how COVID-19 compares to other viruses with regard to transmission and presence in CO2 during MIS. The statements by these groups have created uncertainty and

This article is protected by copyright. All rights reserved confusion regarding the safety of performing MIS during the COVID-19 pandemic and surgeons and other health care workers are requesting clarity on the topic.

Several surgical societies have addressed the potential risk of COVID-19 transmission during MIS, most notable SAGES and The Royal College of Surgeons. The statements formulated by these groups focus on the CO2 insufflation that is established during MIS procedures such as laparoscopic, video-assisted thoracoscopic (VATS), and robotic surgery. The concern raised is that CO2 could theoretically contain COVID-19 particles and that aerosolization could expose health care workers to infectious virus if there is unrestricted release of CO2 into the operating room. Coupled with the fact that CO2 is under pressure during MIS procedures, the potential theoretically exists for viral exposure to health care workers in proximity to the surgical field.

The basis for the society statements are prior published reports of viral particles contained within CO2 aerosol as well as surgical plume created by laser vaporization procedures and electrocautery. One of the studies referenced by the society statements concerned patients with Hepatitis B undergoing MIS procedures where viral RNA was detected in 10 of 11 patients when surgical smoke was tested (3) . Another study evaluating laser vaporization found positive cultures for bacteria (Coryne bacterium) from the laser plume, but no virus was detected by culture (4) . There were also case reports mentioned of exposed surgeons infected with Human Papilloma Virus (HPV) in patients undergoing laser ablation of HPV tumors (5) . Based on these reports with other viruses and limited knowledge of COVID-19 in tissue and blood, the Surgical Societies raised concerns about the potential for COVID-19 in CO2 aerosol created during MIS procedures. While the connection from prior studies to COVID-19 represents an extrapolation, the Societies do acknowledge "there is no current data demonstrating an aerosol presence of the COVID-19 virus released during abdominal surgery. The data referenced was on the detection of other viruses in surgical smoke" (6).

One study that has gained attention and referenced in the Society statements was recently fasttracked published in Annals of Surgery (7). This is a report by surgeons from China and Italy on their perspective on surgical care during the COVID-19 crisis. This is essentially an opinion

This article is protected by copyright. All rights reserved paper of what the authors feel constitutes safe surgical practice in a time of overwhelming patient demand and limited resources. Many of their recommendations are well meaning and based on common sense, however the concerns raised about COVID-19 in CO2 during MIS procedures and the risk to health care workers are not based on evidence. The authors state "the risk (aerosol exposure) is definitely higher in laparoscopic than in traditional open surgery." This statement on risk is based on the assumption that COVID-19 is present in CO2, and to date, that has not been established. The information presented in this report is best characterized as expert opinion (Level 5 evidence). 

This article is protected by copyright. All rights reserved professionals, minimizing aerosol dispersal during laparoscopic procedures, and prioritizing urgent urologic procedures while postponing those at lower risk (9) .

 There is no current evidence to demonstrate COVID-19 in the CO2 plume created during

 There is no clear evidence that active virus is in the blood stream in COVID-19 infected patients (10) . In the same report, COVID-19 RNA was found in feces, but there was no viable virus. 

This article is protected by copyright. All rights reserved  MIS is superior to open surgery with regard to several patient outcomes across many disease states and conversion to open surgery represents a deviation from standard of care.

 Because of the uncertainty surrounding COVID-19 in the CO2 plume, measures to decrease viral exposure to the surgical team should be performed.

Despite the limited number of evidence-based studies addressing the aerosolization of viral particles, there remains concern for the potential presence of COVID-19 in CO2 during MIS.

Cov-1 in that there is plausible transmission of the virus via aerosol or fomite routes (11). The study demonstrates that COVID-19 can remain viable and infectious for hours in aerosolized materials and for days on surfaces. Therefore, efforts should be made to limit cautery plume creation during MIS and CO2 release into the operating room. These efforts to reduce aerosolization and exposure of surgical personnel have been taken from Society recommendations and include:

It has been recommended that patients undergoing surgery be tested for COVID-19 prior to the procedure. Patients with symptoms consistent with COVID-19 should undergo testing prior to surgery if the clinical situation allows for delay. With accumulating data on patients undergoing surgery in the setting of active COVID-19 infection, it is now more important than ever to clarify the COVID-19 status of patients undergoing any procedure. Lei et al recently reported on 34 patients undergoing elective surgery in the setting of positive testing. Alarmingly, 44% of these surgical patients required ICU care following surgery and 7 patients died after ICU admission (12) . Although this small case series should be taken seriously, the true effect of COVID-19 in the post-operative period remains unknown as it is unclear how many patients underwent elective surgery in the study who were potentially COVID-19 positive while being asymptomatic.

This article is protected by copyright. All rights reserved Due to the relatively long incubation period of COVID-19 (3-14 days) (13) , and the now recognized cohort of virus-positive asymptomatic patients in the community setting, we recommend that all patients be tested prior to surgery as permitted by the availability of testing supplies by the institution. Real-Time PCR assays detecting viral RNA have been the mainstay of testing in the United States thus far. These tests have demonstrated efficacious, though variable results with regards to sensitivity and false negative rates (14) . PCR assay performance may also rely on sample type, skill of collection, and varying stages of infection in the patient (15) . Given this information, we recommend the most comprehensive testing techniques available. Imaging studies, such as CT chest, have also been utilized as a potential rapid and reliable testing platform for COVID-19. Ai et al. demonstrated a 97% sensitivity when utilized in COVID-19 positive patients based on RT-PCR testing (17) . Although CT chest imaging may be sensitive for

This article is protected by copyright. All rights reserved detecting COVID-19, it lacks specificity. Furthermore, CT manifestations of COVID-19 tend to occur later in the disease process and may miss patients with earlier sequelae of the virus (18). At this time, we do not recommend widespread utilization of CT imaging as a diagnostic tool prior to elective surgery.

If a patient were to test positive, the AAGL statement recommends delaying surgery until the patient has recovered from COVID-19 if it does not put the patient at risk. If a patient were to test negative, with or without symptoms, consideration for a false negative test should be made and patients treated as "positive until proven otherwise". Therefore, patients without COVID-19

testing and those testing negative should be treated as potentially positive and further steps to mitigate exposure should be performed during the surgical procedure.

All operating room personnel involved with MIS procedures should ideally be provided personal protection equipment (PPE) to include N-95 masks or CAPRs (Controlled Air Purifying Respirators) given the unknown risk of virus in the CO2 plume. Some studies suggest that standard surgical masks provide protection on par with N-95 masks (19). In a randomized study involving over 2,300 health care workers comparing those who wore N-95 masks to those with standard medical masks, there was no difference in influenza acute respiratory illness or infections between the two groups. This experience is potentially transferrable to COVID-19 as the size of Influenza A is between 80-120 nm (0.08 -0.12 microns) (20) and COVID-19 is recognized to be between 60-140 nm (0.06 -0.14 microns). In addition to masks, full PPE to include shoe covers, impermeable gowns, protective head covering, gloves and eye protection should be utilized by all members the operative team.

The minimum number of health care workers should be in the operating room during MIS procedures and only essential personnel should be present to limit traffic and exposure. Breaks in and out of the room should be limited to decrease personnel exposure and limit the amount of necessary PPE. Due to potential limitations in communication while wearing full PPE, conversations in the operating room should be limited to essential surgical-related topics.

This article is protected by copyright. All rights reserved Surgical training should be altered to decrease exposure to non-essential personnel, reduce operative times, and conserve limited PPE resources.

Both intubation and extubation of the patient are powerful aerosol generating procedures and pose a high risk to operating room personnel. Potential AGPs in the operating room aside from surgical smoke include tracheal intubation, manual ventilation, cardiopulmonary resuscitation and suctioning (21) . The American Society of Anesthesiologists (ASA) has put forth recommendations in the setting of COVID-19 including limiting fiberoptic intubation and considering rapid sequence intubation (RSI) in order to avoid manual ventilation (22) . Although negative-pressure operating rooms have been recommended to reduce potential viral contamination (23), these are not readily available at many institutions. Therefore, only core anesthetic staff should be present during intubation and extubation. According to the Association for Professionals in Infection Control and Epidemiology (APIC), "the established standard for operating rooms requires 20 air changes per hour" (24). With this information, along with the CDC guidelines on time required for airborne contaminant removal (25), a minimum of 20 minutes should be observed prior to entering the operating room after intubation.

To decrease the risk of virus release into the CO2 plume, steps can be taken to improve tissue dissection and division. These include reducing the electrocautery settings, decreasing application time, improving tissue moisture to reduce tissue charring and smoke formation. ideally be connected to a filtered device with an ultra-low particulate air (ULPA) or highefficiency particulate air (HEPA) filter and not to an in-room canister connected to wall suction.

There is no way to completely prevent CO2 escape during a MIS procedure as the "closed" ports with a valve will leak with instrument insertion. However, there are technologies available to filter the CO2 and plume created during MIS procedures. This would reduce the amount of potential untreated aerosol released into the operating room.

COVID-19 particles are estimated to be between 0.06 and 0.14 microns (60 to 140 nm, Table 1 ).

To reduce virus in CO2 aerosol, the filtration system should ideally be smaller than the diameter of the virus. There are several filtration systems available to address surgical plume and eliminate virus as well as other products created during plume formation (26) , but these options may vary depending on hospital location and local industry partners.

A technology currently available for MIS is the Airseal insufflation/smoke evacuation system by Conmed (USA) and Surgiquest (UK). Airseal mode is a high flow insufflation system with concurrent smoke evacuation in a low evacuation mode (3 liters/min) and high evacuation mode (8 liters/min). The Airseal mode uses a valve-less port with a virtual valve created by an airflow "shield" (Figure 1 ). The Airseal mode provides smoke evacuation through a 0.01-micron filter which is smaller than the recognized diameter of COVID-19. This technology allows for pressure release which is beneficial during increases in pressure during the procedure (patient bucking), however, it allows CO2 escape due to the open port configuration and is not ideal when there is concern for plume containing virus. The Society

This article is protected by copyright. All rights reserved statements have recommended a "closed" insufflation system to reduce CO2 leakage in distinction to Airseal mode which is "open".

Perhaps unknown to some surgeons the same Airseal insufflation box offers another mode known as smoke evacuation mode (SEM) which is a closed circulation of CO2 with the CO2 filtered through a 0.01-micron ULPA filter (Figure 2 ). This is allows filtration at a smaller particle size than the recognized diameter of COVID-19. The SEM uses standard laparoscopic ports with one line of the dual lumen tube as the CO2 "in" side and the other end of the tube as the "out" which passes through the ULPA filter ( Figure 3) . The SEM is a closed system and provides CO2 flow at standard inflow rates (20 or 40 liters/min).

Another option is the PneumoClear device made by Stryker (Figure 4 ). This is a closed circulating insufflation system with CO2 passed through a 0.08-micron ULPA filter. This system also offers a "desufflation" mode which removes the CO2 contents and passes them through the ULPA filter. The PneumoClear device requires the updated version of the Stryker insufflator.

There are also inline filters available to remove small particles from CO2 aerosol and these options do not require additional insufflators or tube sets. The Plume Port Active (Buffalo Filter) made by Conmed ( Figure 5 ) and the Pureview filter made by Stryker ( Figure 6 ). Both are inline filters that are connected to the side port of laparoscopic port and then to suction tubing. The amount of suction will need to be regulated to keep up with CO2 inflow to maintain working space and visibility. Both filters contain a 0.1-micron filter which is larger than reported COVID-19 particles.

Another source of CO2 aerosol that may impact surgical staff is the laparoscopic suction device used by the surgeon during laparoscopic and VATS procedures and the bedside assistant during robotic surgery. This suction device is usually connected to a suction canister connected to wall suction and goes unfiltered. There is a substantial volume of CO2 removed with this device and this should ideally be filtered. Most laparoscopic suction devices have a standard suction connection and filtration options for this type of connection are limited.

This article is protected by copyright. All rights reserved One option to address CO2 plume from the suction device is to connect the suction tubing to a Neptune Waste Management System (Stryker, Figure 7) . The Neptune possesses both a ULPA filter on the side of the unit (Figure 8 ) as well as a HEPA filter on the front of the device. The front ports readily accept standard suction tubing from a laparoscopic suction device. The side filter containing the ULPA filter requires a separate adaptor to filter CO2 plume. The  Staff should remain remote from the surgical field if their job allows.

 Efforts should be made to reduce surgical plume creation by reducing electrocautery settings, application time, and tissue desiccation.

 CO2 working pressure should be reduced to the lowest acceptable level to allow a safe operating space and maintain visibility  Uncontrolled release of CO2 from the abdomen should be avoided during instrument placement, tissue extraction, or release of CO2 at the end of the case. Efforts should be made to suction the residual CO2 from the patient into a filtration system.

 Efforts should be made to use a closed insufflation system to reduce escape of CO2 into the OR environment.

 CO2 from the working space should be filtered through a closed filtration system using the smallest filter available.

 CO2 from the suction devices should also be filtered through a filtration system using the smallest filter available.

Concern has been raised regarding the risk of exposure to healthcare workers in the operating room from CO2 created during MIS procedures in patients potentially harboring COVID-19.

The risk remains unclear at this time based on the lack of definitive data demonstrating active

This article is protected by copyright. All rights reserved COVID-19 virus present in CO2 aerosol. Despite this uncertainty, efforts to protect operating room staff should be implemented to decrease exposure to surgical smoke created during MIS procedures. These efforts include pre-operative testing in all patients scheduled for MIS surgery, comprehensive personal protective equipment for staff, and reducing the production of surgical 

SAGES and EAES Recommendations Regarding Surgical Response to COVID-19 Crisis

Royal College of Surgeons. Intercollegiate General Surgery Guidance on COVID-19

Detecting hepatitis B virus in surgical smoke emitted during laparoscopic surgery

Microbiologic activity in laser resurfacing plume and debris

HPV positive tonsillar cancer in two laser surgeons: case reports

Risk of acquiring human papillomavirus from the plume produced by the carbon dioxide laser in the treatment of warts

Minimally Invasive Surgery and the Novel Coronavirus Outbreak: Lessons Learned in China and Italy

Invasive Gynecologic Surgery During the COVID-19 Pandemic

Urology Section) Guidelines During COVID-19 Emergency

Virological assessment of hospitalized patients with COVID-2019. Nature. 2020. 11

Clinical Characteristics of Coronavirus Disease 2019 in China

Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019

SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients

Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases

Accepted Article This article is protected by copyright. All rights reserved 18

N95 Respirators vs Medical Masks for Preventing Influenza Among Health Care Personnel: A Randomized Clinical Trial

Size distribution analysis of influenza virus particles using size exclusion chromatography

Nosocomial Transmission of Emerging Viruses via Aerosol-Generating Medical Procedures

American Society of Anesthesiologists. COVID-19 Information for Healthcare Professionals

Association for Professionals in Infection Control and Epidemiology. APIC Implementation Guide: Infection Preventionist's Guide to the OR

Enviromental Infection Control in Health-Care Facilities

Chemical composition of smoke produced by high-frequency electrosurgery in a closed gaseous environment. An in vitro study

This article is protected by copyright. All