key: cord-0755858-z8ma2jx0 authors: Antunes, Diandra; Lami, Mariam; Chukwudi, Agbim; Dey, Abishek; Patel, Mahul; Shabana, Amanda; Shams, Mohamed; Slack, Zoe; Bond-Smith, Giles; Tebala, Giovanni D. title: COVID-19 Infection risk by open and laparoscopic surgical smoke: a systematic review of the literature date: 2021-03-03 journal: Surgeon DOI: 10.1016/j.surge.2021.02.003 sha: 4688c8b4a7227b7fa4b8664413fae54904dea0a2 doc_id: 755858 cord_uid: z8ma2jx0 Background The current COVID-19 pandemic has greatly changed the way surgery is delivered. In particular, current guidelines and policies have highlighted the need to use high level Personal Protective Equipment to reduce the risk of viral infection during open and laparoscopic surgical procedures. In particular, it was felt that the laparoscopic approach was at higher risk of viral transmission due to the chimney effect of the smoke escape from the trocars during and after the procedure. However, with this being a new and largely unknown viral agent, guidelines have been based on speculation and extrapolation from previous studies conducted in completely different situations, and led to anxiety amongst surgeons and theatre staff. We decided to conduct a systematic review of the Literature to try to clarify whether inhalation of surgical smoke can increase the risk of COVID-19 infection. Methods A thorough search of the relevant Literature was performed following the PRISMA guidelines and the most relevant papers on this topic were selected for qualitative analysis. Duplicates, review, personal opinions and guidelines have been excluded. Quantitative analysis has not been performed due to the lack of homogeneous high-quality studies. Results Literature search identified 740 papers but only 34 of them were suitable for qualitative analysis. The quality of those studies is generally quite low. We were not able to find any evidence directly linking surgical smoke with viral transmission, other than in patients with active HPV infection. Discussion Inhalation of surgical smoke can be generally hazardous, and therefore the use of PPE during surgical operations must be recommended in any case. However, the present systematic review of the existent Literature did not identify any significant evidence of the risk of viral transmission with the surgical smoke, therefore the current guidelines restricting the use of laparoscopy and/or diathermy during the current Covid-19 pandemic may be considered excessive and non-evidence based. COVID-19 is a coronavirus causing a severe pandemic and globally affecting all aspects of healthcare at present. The practice of surgery, both elective and emergency, has significantly changed over the last few months, as attempts have been made to minimise the risks of potential transmission of COVID-19infection. The use of personal protective equipment (PPE) has been advocated by national and international guidelines as the best method to reduce the risk to theatre staff, particularly in Aerosol Generating Procedures (AGP) (1) . Surgical guidelines, probably published in the haste of the first wave of the COVID-19 pandemic, went further to recommend avoiding laparoscopic surgery as much as possible, fearing that the chimney effect of high flow intraperitoneal gas escape during and after the procedure would increase the risk of viral transmission. They also recommended minimal use of diathermy to reduce smoke creation, with the assumption that surgical plume may cause viral spread and infection (2) . While it has been demonstrated that intubation and other procedures on the upper airways are to be considered AGP, and therefore at high risk for viral transmission, it is not clear if a laparotomy or laparoscopy is in fact an AGP. In other terms, it is not clear if the surgical plume must be considered "aerosol". Furthermore, while the risks linked to the inhalation of the surgical smoke have been discussed for many years, it is not yet clear whether this carries an additional transmission risk of viral infection, particularly with regards to non-blood borne viruses such as COVID-19. We decided to conduct a systematic review of the Literature with the aim of answering the following questions: 1. Is there any infective risk for surgeons and theatre staff exposed to surgical Other relevant articles were identified from the references of those already selected. After removing the duplicates, titles and abstracts of those remaining were screened to confirm their relevance to our clinical questions. Articles with no available abstracts were advanced to the next step. A further full-text selection to confirm eligibility was performed on the remaining articles, and the most relevant ones selected for qualitative analysis. Reviews, personal opinions and guidelines have not been used for qualitative analysis but some of them were used in the discussion. Quantitative analysis was not performed due to the lack of homogeneous, highquality studies. The results of the Literature search are reported in Figure 1 according to the PRISMA guidelines (3) . Thirty-four articles were selected for final review. Four of them were experimental studies on animals (2 of these were associated with clinical cohort studies), 4 were case reports, 17 were clinical cohort studies and 9 were experimental laboratory studies. Is there any infective risk for surgeons and theatre staff exposed to surgical smoke? Although numerous studies demonstrate the presence of infective material in surgical smoke, these studies fail to demonstrate the infectivity of such cells. One study investigating the smoke plumes secondary to CO2 laser resurfacing demonstrated the potential for bacterial transmission via surgical smoke, but no infectivity was demonstrated with viral transmission (4). In terms of investigating the potential for viral transmission via surgical smoke plumes generated from electrocautery, the evidence currently available is that of four separate case reports. The first reports a case of laryngeal papillomatosis originating from HPV 6 and 11 in a surgeon with no identifiable risk factors, apart from a clear occupational history of treating anogenital condylomas caused by the same viral strain (5) . The second case report (6) discussed a similar case of laryngeal papillomatosis in a gynaecology operating room nurse, who had assisted in both electrosurgical and laser surgical excisions of anogenital condylomas. Another paper highlighted a case of HPV-16 positive tonsillar squamous cell carcinoma in a 53-year old gynaecologist who had a 20 year history of exposure to laser plumes, and another case of base of tongue cancer in a gynaecologist with a similar 30 year history of occupational exposure, with no other identifiable risk factors (7) . None of the other available studies showed any evidence to suggest an infective risk to theatre staff, and no studies were performed in non-blood borne or non-local tissue viruses. In this review, a total of seven studies (8) (9) (10) (11) (12) (13) (14) were found demonstrating no detection whatsoever of infective cells in surgical smoke plumes. Only one of these studies (8) tested the plumes generated from electrocautery, whilst the remaining studies used laser plumes. Four studies successfully demonstrated the presence of virus in smoke extraction devices, however, they did not demonstrate actual infectivity of the virus (15) (16) (17) (18) . Three of these studies related to gynaecological procedures using CO2 laser and loop electrosurgical excision procedure plumes, whilst the fourth was an experimental study using an excimer laser. None of these studies were related to laparoscopic surgery or electrocautery techniques. One study suggested that viable viral DNA can be found in surgical plumes, but this was only demonstrated with short term cultures of particulate debris found in plume collection tubing itself, which were no longer viable at 28 days (19) . Another study demonstrated the infectivity of HIV infected cells found in cool aerosols generated by certain surgical power tools, but showed no infectivity amongst cells in electrocautery smoke (20, 21) . In terms of laparoscopic surgery, one study identified hepatitis B virus in surgical plumes amongst patients who had undergone laparoscopic abdominal surgery (22) . Although the infectivity of the virus was not tested, this study suggested that surgical plumes may transmit certain blood borne viruses such as HBV. Four animal studies investigating the infectivity of viruses via laser smoke plume have previously been performed, one of which showed no evidence of viral presence or transmission (8) . Two studies demonstrated viral infectivity amongst particles identified in surgical smoke secondary to CO2 laser cautery specifically. The first study demonstrated infectivity of laser plume particles by using the plume to reinoculate bovine papillomavirus-induced cutaneous fibropapillomas (23) , whilst the second used laser plume to reinfect mice with papillomavirus (24) . The last study only demonstrated the presence of viral particles, but also showed no infectivity of these particles (25) . With regards to human transmission risk, a large study performed at the Mayo Clinic reported a slightly higher incidence of nasopharyngeal verrucae amongst surgeons treating patients with verrucae (26) . Overall wart incidence amongst the surgeons, however, was no higher than the general population. A similar study concluded that the higher incidence of verrucae amongst operating surgeons was more likely secondary to direct contact rather than via plume transmission, as verrucae were noted to be highest on surgeons' hands, with no verrucae being found in the upper airway, as had previously been suggested (27) . Another study confirmed infectivity of bovine papillomavirus, but did not demonstrate the same for human papillomavirus (28) . Interestingly, this paper highlighted that higher titres of Papillomavirus DNA were recovered from laser vapour than electrocoagulation vapour, in keeping with the theory that electrocoagulation may result in particles too small for adequate titres needed for viral transmission. virus, can survive excimer laser ablation, although no demonstration of its infective potential was made (14, 18) . The primary route of transmission of COVID-19 is via respiratory droplets (29, 30) . In keeping with this knowledge, recent studies have established that viral particles can be detected in various body fluids including tears, faces, saliva, and even semen (31) . Concerns regarding the potential presence of COVID-19's in aerosols have caused much debate and anxiety amongst healthcare workers and the public. Our review established that no evidence currently exists to demonstrate airborne transmission of COVID-19, or the presence of the virus in surgical smoke. A recently published article suggested that COVID-19 virus is unlikely to be transmitted via aerosols for various reasons (32) . Firstly, the reproduction number of COVID-19 (estimated to be around 2.5) is far lower than other viruses with known aerosol spread such as measles, which has a reproductive number of around 18. Furthermore, recent reports have highlighted the low secondary attack rate of COVID-19, which suggests that only about 5% of contacts with patients become positive. This has been shown to be largely dependent on the duration and nature of interaction, with transmission studies suggesting that healthcare workers who care for infected patients whilst wearing face masks alone have a less than 3% risk of contracting the virus (33) (34) (35) . These findings are in keeping with the current evidence that suggests COVID-19's primary mechanism of transmission is via respiratory secretions. Electrocautery, ultrasonic scalpel tissue dissection and laser tissue ablation are all known to create 'surgical smoke' which has led to numerous studies aimed at identifying its components and its potential for viral, bacterial and even malignant tissue transmission. Surgical smoke, sometimes also referred to as plume, aerosol J o u r n a l P r e -p r o o f or vapour, is a surgically generated byproduct of tissue combustion. The quantity of generated surgical smoke varies depending on the procedure being performed, the nature of the tissue and the surgical tool being used. Electrocautery generates particles with a much smaller size (0.07 micrometres) than laser ablation techniques (0.35-6.5 micrometres) (36) . During surgical procedures, diathermy results in the rupture of target cell membranes as they reach boiling point, which subsequently creates 'surgical smoke' containing water vapour (which constitutes approximately 95%) and a small quantity of charred proteins and organic matter, from within the cells themselves (forming the final 5%) (37) . This process causes the release of contaminants such as carbonised cell fragments and gaseous hydrocarbons, including toluene, acrolein, formaldehyde, benzene and hydrogen cyanide. Further studies are required in this area and would benefit from careful design to reliably assess staff exposure to surgical smoke and any subsequent reporting of ill health effects (39) . The COVID-19 pandemic is affecting the way we practice surgery on a daily basis. At the beginning of the pandemic (February and March 2020), governments, healthcare systems, colleges and scientific societies produced policies and guidelines that were based on common sense and extrapolations from previous experiences and previously published studies (40) , due to the total lack of knowledge specific to the new coronavirus. Unfortunately, the panic generated by the pandemic had great repercussions on the practice of surgery, particularly when the official guidelines recommended and endorsed non-evidence based approaches to surgical patients (41) . Initial guidance following the COVID-19 pandemic resulted in operating theatre access being almost exclusively restricted to emergency procedures, with caution being advised for any laparoscopic procedures due to the perceived risks of aerosolisation of intraperitoneal viral particles and the potential risk this could pose to theatre staff (42) . NHS England postponed non-emergency surgical procedures for three months from the 15th of April, at which time elective operating had already stopped in Wales, Scotland and Northern Ireland (43) . In addition, guidance suggested minimising or postponing scheduled endoscopic and invasive procedures, and emphasised the need for reliance on a daily, data-driven assessment of the changing risk-benefit for each patient throughout the pandemic (44) . "Protection" sounds like a mantra in the current guidelines, but it is not exactly clear what we are protecting ourselves from. Epidemiologic and laboratory-based studies have raised the suspicion of Covid-19 transmission through aerosol particles, but it must be emphasised that "demonstrating that speaking and coughing can generate aerosols or that it is possible to recover viral RNA from air does not prove aerosolbased transmission" (32) . The same consideration can be made for surgical smoke, whose viral infective properties have yet to be proven. Our systematic review found no reliable evidence to suggest a risk of COVID-19 transmission via surgical smoke and laparoscopic pneumoperitoneum. Previous case studies suggest the potential risk of HPV transmission via surgical smoke (5) (6) (7) . Given that HPV is a local tissue virus, and the nature of surgeries investigated by existing studies involved close proximity of the surgeons to the operating field, the transferability of such evidence to transmission of COVID-19 is highly questionable (50, 51) . Hepatitis B Virus, one of the few viruses which has been detected in surgical smoke, has been shown to tolerate higher electro-surgical temperatures than coronaviruses (52, 53) . Despite this, no evidence exists to demonstrate the infectivity of such particles (54) . Other relevant articles were identified from the references of those already selected. After removing the duplicates, titles and abstracts of those remaining were screened to confirm their relevance to our clinical questions. Articles with no available abstracts were advanced to the next step. A further full-text selection to confirm eligibility was performed on the remaining articles, and the most relevant ones selected for qualitative analysis. Reviews, personal opinions and guidelines have not been used for qualitative analysis but some of them were used in the discussion. Quantitative analysis was not performed due to the lack of homogeneous, highquality studies. The results of the Literature search are reported in Figure 1 according to the PRISMA guidelines (3). Thirty-four articles were selected for final review. Four of them were experimental studies on animals (2 of these were associated with clinical cohort studies), 4 were case reports, 17 were clinical cohort studies and 9 were experimental laboratory studies. Is there any infective risk for surgeons and theatre staff exposed to surgical smoke? Although numerous studies demonstrate the presence of infective material in surgical smoke, these studies fail to demonstrate the infectivity of such cells. One study investigating the smoke plumes secondary to CO2 laser resurfacing demonstrated the potential for bacterial transmission via surgical smoke, but no infectivity was demonstrated with viral transmission (4). In terms of investigating the potential for viral transmission via surgical smoke plumes generated from electrocautery, the evidence currently available is that of four separate case reports. The first reports a case of laryngeal papillomatosis originating from HPV 6 and 11 in a surgeon with no identifiable risk factors, apart from a clear occupational history of treating anogenital condylomas caused by the same viral strain (5) . The second case report (6) In this review, a total of seven studies (8) (9) (10) (11) (12) (13) (14) were found demonstrating no detection whatsoever of infective cells in surgical smoke plumes. Only one of these studies (8) tested the plumes generated from electrocautery, whilst the remaining studies used laser plumes. Four studies successfully demonstrated the presence of virus in smoke extraction devices, however, they did not demonstrate actual infectivity of the virus (15) (16) (17) (18) . Three of these studies related to gynaecological procedures using CO2 laser and loop electrosurgical excision procedure plumes, whilst the fourth was an experimental study using an excimer laser. None of these studies were related to laparoscopic surgery or electrocautery techniques. One study suggested that viable viral DNA can be found in surgical plumes, but this was only demonstrated with short term cultures of particulate debris found in plume collection tubing itself, which were no longer viable at 28 days (19) . Another study demonstrated the infectivity of HIV infected cells found in cool aerosols generated by certain surgical power tools, but showed no infectivity amongst cells in electrocautery smoke (20, 21) . In terms of laparoscopic surgery, one study identified hepatitis B virus in surgical plumes amongst patients who had undergone laparoscopic abdominal surgery (22) . Although the infectivity of the virus was not tested, this study suggested that surgical plumes may transmit certain blood borne viruses such as HBV. Four animal studies investigating the infectivity of viruses via laser smoke plume have previously been performed, one of which showed no evidence of viral presence or transmission (8) . Two studies demonstrated viral infectivity amongst particles identified in surgical smoke secondary to CO2 laser cautery specifically. The first study demonstrated infectivity of laser plume particles by using the plume to reinoculate bovine papillomavirus-induced cutaneous fibropapillomas (23), whilst the second used laser plume to reinfect mice with papillomavirus (24) . The last study only demonstrated the presence of viral particles, but also showed no infectivity of these particles (25) . With regards to human transmission risk, a large study performed at the Mayo Clinic reported a slightly higher incidence of nasopharyngeal verrucae amongst surgeons treating patients with verrucae (26) . Overall wart incidence amongst the surgeons, however, was no higher than the general population. A similar study concluded that the higher incidence of verrucae amongst operating surgeons was more likely secondary to direct contact rather than via plume transmission, as verrucae were noted to be highest on surgeons' hands, with no verrucae being found in the upper airway, as had previously been suggested (27) . Another study confirmed infectivity of bovine papillomavirus, but did not demonstrate the same for human papillomavirus (28) . Interestingly, this paper highlighted that higher titres of Papillomavirus DNA were recovered from laser vapour than electrocoagulation vapour, in keeping with the theory that electrocoagulation may result in particles too small for adequate titres needed for viral transmission. Taravella et al demonstrated that oral polio vaccine virus, unlike varicella zoster virus, can survive excimer laser ablation, although no demonstration of its infective potential was made (14, 18) . The primary route of transmission of COVID-19 is via respiratory droplets (29, 30 Further studies are required in this area and would benefit from careful design to reliably assess staff exposure to surgical smoke and any subsequent reporting of ill health effects (39) . The COVID-19 pandemic is affecting the way we practice surgery on a daily basis. Full PPE as per WHO guidelines was advised for all surgical procedures and electrosurgical units advised to be set to the lowest possible settings for desired effect (as a means of minimising potential aerosolization and smoke formation). Smoke evacuators were advised and surgical equipment used during procedures advised to be cleaned separately from other surgical equipment. Finally, the American College of Surgeons (49) produced specific guidelines that can be used to ensure patient and staff safety across all phases of surgical care. "Protection" sounds like a mantra in the current guidelines, but it is not exactly clear what we are protecting ourselves from. Epidemiologic and laboratory-based studies have raised the suspicion of Covid-19 transmission through aerosol particles, but it must be emphasised that "demonstrating that speaking and coughing can generate aerosols or that it is possible to recover viral RNA from air does not prove aerosolbased transmission" (32) . The same consideration can be made for surgical smoke, whose viral infective properties have yet to be proven. Our systematic review found no reliable evidence to suggest a risk of COVID-19 transmission via surgical smoke and laparoscopic pneumoperitoneum. Previous case studies suggest the potential risk of HPV transmission via surgical smoke (5) (6) (7) . Given that HPV is a local tissue virus, and the nature of surgeries investigated by existing studies involved close proximity of the surgeons to the operating field, the transferability of such evidence to transmission of COVID-19 is highly questionable (50, 51) . Hepatitis B Virus, one of the few viruses which has been detected in surgical smoke, has been shown to tolerate higher electro-surgical temperatures than coronaviruses (52, 53) . Despite this, no evidence exists to demonstrate the infectivity of such particles (54) . Clinical research investigating the questions discussed above, with specific application to COVID-19, must be conducted as soon as possible so that guidelines can be adjusted according to evidence-based findings rather than unproven extrapolations. Intercollegiate General Surgery Guidance on COVID-19 Updated Intercollegiate General Surgery Guidance on COVID-19 Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement Microbiologic activity in laser resurfacing plume and debris Laryngeal papillomatosis with human papillomavirus DNA contracted by a laser surgeon Larynxpapillomatose -erstmalige Anerkennung als Berufskrankheit bei einer OP-Schwester HPV positive tonsillar cancer in two laser surgeons: case reports Occupational exposure of oropharyngeal human papillomavirus amongst otolaryngologists Is papillomavirus detectable in the plume of laser-treated laryngeal papilloma? Investigation of the presence of HPV on KTP laser fibers following KTP laser treatment of papilloma Absence of human papillomavirus DNA in the plume of erbium:YAG laser-treated warts Are laryngeal papilloma virusinfected cells viable in the plume derived from a continuous mode carbon dioxide laser, and are they infectious? A preliminary report on one laser mode Lack of virus transmission by the excimer laser plume Do intact viral particles survive excimer laser ablation? Is surgical plume developing during routine LEEPs contaminated with high-risk HPV? A pilot series of experiments Human papillomavirus DNA in LEEP plume Low risk of contamination with human papilloma virus during treatment of condylomata acuminata with multilayer argon plasma coagulation and CO₂ laser ablation Live virus survives excimer laser ablation Presence of human immunodeficiency virus DNA in laser smoke Human immunodeficiency virus-1 (HIV-1) in the vapors of surgical power instruments Detection of hepatitis C virus RNA in the ultrasonic dissector irrigating solution used in liver surgery Detecting hepatitis B virus in surgical smoke emitted during laparoscopic surgery Viral disease transmitted by laser-generated plume (aerosol) Infectivity of murine papillomavirus in the surgical byproducts of treated tail warts Papillomavirus in the Vapor of Carbon Dioxide Laser-Treated Verrucae Risk of acquiring human papillomavirus from the plume produced by the carbon dioxide laser in the treatment of warts A retrospective study on the hazards of the carbon dioxide laser plume Infectious papillomavirus in the vapor of warts treated with carbon dioxide laser or electrocoagulation: detection and protection Transmission of COVID-19 virus by droplets and aerosols: A critical review on the unresolved dichotomy Identifying airborne transmission as the dominant route for the spread of COVID-19 Intercollegiate General Surgery Guidance on COVID-19 Updated Intercollegiate General Surgery Guidance on COVID-19 Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement Microbiologic activity in laser resurfacing plume and debris Laryngeal papillomatosis with human papillomavirus DNA contracted by a laser surgeon Larynxpapillomatose -erstmalige Anerkennung als Berufskrankheit bei einer OP-Schwester HPV positive tonsillar cancer in two laser surgeons: case reports Occupational exposure of oropharyngeal human papillomavirus amongst otolaryngologists Is papillomavirus detectable in the plume of laser-treated laryngeal papilloma? Investigation of the presence of HPV on KTP laser fibers following KTP laser treatment of papilloma Absence of human papillomavirus DNA in the plume of erbium:YAG laser-treated warts Are laryngeal papilloma virusinfected cells viable in the plume derived from a continuous mode carbon dioxide laser, and are they infectious? A preliminary report on one laser mode Lack of virus transmission by the excimer laser plume Do intact viral particles survive excimer laser ablation? Is surgical plume developing during routine LEEPs contaminated with high-risk HPV? A pilot series of experiments Human papillomavirus DNA in LEEP plume Low risk of contamination with human papilloma virus during treatment of condylomata acuminata with multilayer argon plasma coagulation and CO₂ laser ablation Live virus survives excimer laser ablation Presence of human immunodeficiency virus DNA in laser smoke Human immunodeficiency virus-1 (HIV-1) in the vapors of surgical power instruments Detection of hepatitis C virus RNA in the ultrasonic dissector irrigating solution used in liver surgery Detecting hepatitis B virus in surgical smoke emitted during laparoscopic surgery Viral disease transmitted by laser-generated plume (aerosol) Infectivity of murine papillomavirus in the surgical byproducts of treated tail warts Papillomavirus in the Vapor of Carbon Dioxide Laser-Treated Verrucae Risk of acquiring human papillomavirus from the plume produced by the carbon dioxide laser in the treatment of warts A retrospective study on the hazards of the carbon dioxide laser plume Infectious papillomavirus in the vapor of warts treated with carbon dioxide laser or electrocoagulation: detection and protection Transmission of COVID-19 virus by droplets and aerosols: A critical review on the unresolved dichotomy Identifying airborne transmission as the dominant route for the spread of COVID-19 SARS-CoV2 in Different Body Fluids, Risks of Transmission, and Preventing COVID-19: A Comprehensive Evidence-Based Review Airborne Transmission of SARS-CoV-2: Theoretical Considerations and Available Evidence Contact tracing assessment of COVID-19 transmission dynamics in Taiwan and risk at different exposure periods before and after symptom onset New York State Coronavirus 2019 Response Team. COVID-19 testing, epidemic features, hospital outcomes, and household prevalence Epidemiological characteristics of infection in COVID-19 close contacts in Ningbo. Article in Chinese Diathermy, and Surgical Energy Devices: Are Surgical Teams at Risk During the COVID-19 Pandemic? Awareness of surgical smoke hazards and enhancement of surgical smoke prevention among the gynecologists Healthcare Worker-common causes of asthma. Health and Safety Executive Evidence based literature review. Prepared by the Health and Safety Laboratory for the Health and Safety Executive Guidelines and recommendations during the COVID-19 pandemic: A word of caution In response to: Laparoscopic surgery and the coronavirus disease 2019 pandemic: A word from a different hymn sheet COVID-19: Good practice for Surgeons and Surgical Teams Covid-19: all non-urgent elective surgery is suspended for at least three months in England Updated General Surgery Guidance on COVID-19 30th Protecting surgery through a second wave Updated Intercollegiate General Surgery Guidance on Covid-19 Clinical Guide to Surgical Prioritisation During the Coronavirus Pandemic EAES and SAGES recommendations regarding surgical response to COVID-19 crisis Roadmap for Maintaining Essential Surgery during COVID-19 Pandemic Risk of papillomavirus infection in carbon dioxide laser treatment of genital lesions Carbon dioxide laser energy disperses human papillomavirus deoxyribonucleic acid onto treatment fields Assessing the risk of viral infection from gases and plumes during intra-abdominal surgery: a systematic scoping review The Effects of Temperature and Relative Humidity on the Viability of the SARS Coronavirus Analysis of plume emissions after papovavirus irradiation with the carbon dioxide laser COVID-19: smoke testing of surgical mask and respirators Human papillomavirus DNA in CO2 laser-generated plume of smoke and its consequences to the surgeon Polymerase chain reaction identification of human papillomavirus DNA in CO2 laser plume from recurrent respiratory papillomatosis. Otolaryngol Head Neck Surg In vitro production of viable bacteriophage in carbon dioxide and argon laser plumes Viable bacteriophage in CO2 laser plume: aerodynamic size distribution Bacteriophage phi X-174 as an aerobiological marker for surgical plume generated by the electromagnetic field focusing system Studies on the transmission of viral disease via the CO2 laser plume and ejecta -Clinical studies supporting current guidelines on COVID-19 have yet to be done -Previous evidence suggesting HBV, HIV and HPV virus detection in plumes is low level -There is currently no evidence of COVID-19 viral transmission risk via surgical smoke -Current guidelines may be considered excessive and non-evidence based