Electrocautery Smoke Research Articles

Clearing the Smoke: The Evidence behind Risk of Electrocautery Smoke and Mitigation Strategies.

Electrocautery has been a useful, fundamental instrument utilized for surgical procedures since its implementation in the 1920s. However, concerns exist regarding the health hazards of the by-product smoke associated with the use of electrocautery. A comprehensive review of articles on the composition, mitigation, and effects of smoke was conducted using the PubMed search engine and excluding articles that did not meet the predetermined inclusion criteria. From January 1963 to December 2021, a total of 264 articles resulted, and a total of 69 articles were included in this narrative review. Surgical smoke contains volatile organic compounds, polycyclic aromatic compounds, viral particles, and ultrafine particles. There has been some evidence of mutagenicity to bacterial cells during animal in vivo studies, and one human survey study has shown similar mutagenic effects. We also discuss additional hemostatic techniques that can be used, including the use of hemostatic and antithrombolytic agents, epinephrine infiltration, and the use of tourniquet when appropriate. Further studies should be conducted regarding human effects, but until the data are available, we recommend precautionary measures and actions to protect operating room staff from cautery smoke exposure.

The Impact of Electrocautery Smoke on Surgical Staff and the Efficacy of Normal Surgical Masks Versus N95 Masks.

Electrocautery is a commonly used technique in surgical procedures, generating smoke that poses health risks to surgical staff. This study investigates the comparative efficacy of normal surgical masks versus N95 masks in mitigating the harmful effects of electrocautery smoke. Through a systematic review of literature spanning two decades, we explore the causes and effects of electrocautery smoke exposure, including potential long-term inhalation effects. Our findings highlight significant disparities in the protection offered by different masks and underscore the importance of adequate respiratory protection in surgical settings. In addition, we examine the factors influencing the generation and composition of electrocautery smoke, such as the power settings used, the type of tissue being cauterized, and the duration of the procedure. Furthermore, we discuss the potential health risks associated with long-term exposure to electrocautery smoke, including the possibility of respiratory conditions, cardiovascular effects, and carcinogenicity. Our analysis also addresses the importance of implementing appropriate smoke evacuation systems and optimizing operating room ventilation to minimize the concentration of smoke particles in the surgical environment. Overall, this comprehensive analysis provides valuable insights into the impact of electrocautery smoke in surgical settings and the varying levels of protection offered by different masks.

Surgical smoke: a matter of hygiene, toxicology, and occupational health.

The use of devices for tissue dissection and hemostasis during surgery is almost unavoidable. Electrically powered devices such as electrocautery, ultrasonic and laser units produce surgical smoke containing more than a thousand different products of combustion. These include large amounts of carcinogenic, mutagenic and potentially teratogenic noxae. The smoke contains particles that range widely in size, even as small as 0.007 µm. Most of the particles (90%) in electrocautery smoke are ≤6.27 µm in size, but surgical masks cannot filter particles smaller than 5 µm. In this situation, 95% of the smoke particles which pass through the mask reach deep into the respiratory tract and frequently cause various symptoms, such as headache, dizziness, nausea, eye and respiratory tract irritation, weakness, and abdominal pain in the acute period. The smoke can transport bacteria and viruses that are mostly between 0.02 µm and 3 µm in size and there is a risk of contamination. Among these viruses, SARS-CoV-2, influenza virus, HIV, HPV, HBV must be considered. The smoke may also carry malignant cells. The long-term effects of the surgical smoke are always ignored, because causality can hardly be clarified in individual cases. The quantity of the smoke changes with the technique of the surgeon, the room ventilation system, the characteristics of the power device used, the energy level at which it is set, and the characteristics of the tissue processed. The surgical team is highly exposed to the smoke, with the surgeon experiencing the highest exposure. However, the severity of exposure differs according to certain factors, e.g., ventilation by laminar or turbulent mixed airflow or smoke evacuation system. In any case, the surgical smoke must be removed from the operation area. The most effective method is to collect the smoke from the source through an aspiration system and to evacuate it outside. Awareness and legal regulations in terms of hygiene, toxicology, as well as occupational health and safety should increase.

Spinal fusion is an aerosol generating procedure.

Transmission of severe acute respiratory syndrome coronavirus 2 can occur during aerosol generating procedures. Several steps in spinal fusion may aerosolize blood but little data exists to quantify the risk this may confer upon surgeons. Aerosolized particles containing infectious coronavirus are typically 0.5-8.0 μm. To measure the generation of aerosols during spinal fusion using a handheld optical particle sizer (OPS). We quantified airborne particle counts during five posterior spinal instrumentation and fusions (9/22/2020-10/15/2020) using an OPS near the surgical field. Data were analyzed by 3 particle size groups: 0.3-0.5 μm/m3, 1.0-5.0 μm/m3, and 10.0 μm/m3. We used hierarchical logistic regression to model the odds of a spike in aerosolized particle counts based on the step in progress. A spike was defined as a > 3 standard deviation increase from average baseline levels. Upon univariate analysis, bovie (P < 0.0001), high speed pneumatic burring (P = 0.009), and ultrasonic bone scalpel (P = 0.002) were associated with increased 0.3-0.5 μm/m3 particle counts relative to baseline. Bovie (P < 0.0001) and burring (P < 0.0001) were also associated with increased 1-5 μm/m3 and 10 μm/m3 particle counts. Pedicle drilling was not associated with increased particle counts in any of the size ranges measured. Our logistic regression model demonstrated that bovie (OR = 10.2, P < 0.001), burring (OR = 10.9, P < 0.001), and bone scalpel (OR = 5.9, P < 0.001) had higher odds of a spike in 0.3-0.5 μm/m3 particle counts. Bovie (OR = 2.6, P < 0.001), burring (OR = 5.8, P < 0.001), and bone scalpel (OR = 4.3, P = 0.005) had higher odds of a spike in 1-5 μm/m3 particle counts. Bovie (OR = 0.3, P < 0.001) and drilling (OR = 0.2, P = 0.011) had significantly lower odds of a spike in 10 μm/m3 particle counts relative to baseline. Several steps in spinal fusion are associated with increased airborne particle counts in the aerosol size range. Further research is warranted to determine if such particles have the potential to contain infectious viruses. Previous research has shown that electrocautery smoke may be an inhalation hazard for surgeons but here we show that usage of the bone scalpel and high-speed burr also have the potential to aerosolize blood.

Surgical smoke: how an issue in healthcare fits a planetary health framework.

The smoke generated from electrocautery machines may be harmful to health. Healthcare in general, and surgery in particular, has a large environmental footprint. The aims of this study were to discover what healthcare workers thought about the problem of electrocautery smoke, the idea of a surgical smoke-free policy, and to formulate ideas on how the matter could be approached in an environmentally and socially responsible way. Operating room personnel in a tertiary referral hospital were invited to complete a survey about electrocautery smoke: perceived risks, current exposure, and measures to minimise exposure. Quantitative data were analysed in a generalised linear model, and qualitative data by reflexive thematic analysis within a constructivist theoretical framework. The survey response rate was 463/1234 (38%). Most supported a smoke-free policy (89%). Support for a policy was positively correlated with the perceived risk of electrocautery smoke (p<0.001. Support was lower amongst males (p<0.05). Themes from the qualitative analysis developed around nature, society and technology. A framework was developed consisting of earth and its ecosystems, human health, governance, economics, society, and the interconnected of these systems. Although smoke-free policies form part of the solution to electrocautery smoke, they are not the whole solution. Healthcare issues, in this case the issue of electrocautery smoke, could be tackled within a planetary health healthcare framework, promoting a systems approach. Applicability of the framework requires confirmation by further research.

Electrocautery smoke exposure and smoke evacuation in thoracic surgery: A prospective randomized study

Abstract Objective Worldwide, health care professionals working in operating rooms (ORs) are exposed to electrocautery smoke on a daily basis. Aims of this study were to determine the composition and concentrations of electrocautery smoke in the OR using mass spectrometry and investigate whether smoke evacuation systems, operative technique and distance to the cautery source are effective in reducing exposure. Methods Single-center study at our thoracic surgical unit including 122 surgical procedures. Besides room air measurements away from the operating table (n=35) and direct breath analysis (n=3), 84 minimally invasive and open procedures were in each group 1:1 computer randomized to smoke evacuation system (SES) versus no SES use and hazardous compounds were measured at the height of the operating surgeons respiratory tract. Results Irritating, toxic, carcinogenic and mutagenic volaticle organic compounds (VOCs) were observed in OR air, with some exceeding permissible exposure limits (OSHA/NIOSH). Mean total concentration of harmful compounds at surgeon height without SES was 273ppb (±189ppb) with a maximum total concentration of harmful substances of 8991ppb . Maximum total VOC concentrations were 1.6±1.2 ppm (minimally-invasive surgery) and 2.1±1.5 ppm (open surgery), and total maximum VOC concentrations were 1.8±1.3 ppm at the OR table and 1.4±1.0 ppm in OR air in general. Neither difference was statistically significant. In open surgery, SES significantly reduced maximum concentrations of specific VOCs at surgeon height, including aromatics and aldehydes. Conclusion Our data indicate relevant exposure of health care professionals to volatile organic compounds in the OR. Surgical technique and distance to cautery devices did not significantly reduce exposure. SES reduced exposure to specific harmful VOC's during open surgery.

Electrocautery smoke exposure and efficacy of smoke evacuation systems in minimally invasive and open surgery: a prospective randomized study

Worldwide, health care professionals working in operating rooms (ORs) are exposed to electrocautery smoke on a daily basis. Aims of this study were to determine composition and concentrations of electrocautery smoke in the OR using mass spectrometry. Prospective observational study at a tertiary care academic center, involving 122 surgical procedures of which 84 were 1:1 computer randomized to smoke evacuation system (SES) versus no SES use. Irritating, toxic, carcinogenic and mutagenic VOCs were observed in OR air, with some exceeding permissible exposure limits (OSHA/NIOSH). Mean total concentration of harmful compounds was 272.69 ppb (± 189 ppb) with a maximum total concentration of harmful substances of 8991 ppb (at surgeon level, no SES). Maximum total VOC concentrations were 1.6 ± 1.2 ppm (minimally-invasive surgery) and 2.1 ± 1.5 ppm (open surgery), and total maximum VOC concentrations were 1.8 ± 1.3 ppm at the OR table ‘at surgeon level’ and 1.4 ± 1.0 ppm ‘in OR room air’ away from the operating table. Neither difference was statistically significant. In open surgery, SES significantly reduced maximum concentrations of specific VOCs at surgeon level, including aromatics and aldehydes. Our data indicate relevant exposure of health care professionals to volatile organic compounds in the OR. Surgical technique and distance to cautery devices did not significantly reduce exposure. SES reduced exposure to specific harmful VOC’s during open surgery.Trial Registration Number: NCT03924206 (clinicaltrials.gov).

Introduction: Occupational Hazards to the Joint Replacement Surgeon

Introduction: Occupational Hazards to the Joint Replacement Surgeon

Respiratory symptoms associated with electrocautery smoke: a systematic literature review

The smoke produced by the use of electro cauterization is formed by gaseous chemical compounds (gaseous phase) and by particle components (particulate phase) that can trigger harmful, local or systemic, reversible or irreversible effects in people who use this equipment. These chemicals can trigger genetic mutations and cancer in the human body. In addition to mutation and cancer, particles in the smoke of electro-cauterization can be inhaled and retained in the respiratory tract of workers, causing various respiratory signs and symptoms, including foreign body sensation in the throat, pharyngeal burning, nausea, and nasal congestion. It can also cause headache and eye irritation. Objective: To identify studies related to the presence of respiratory symptoms in health professionals related to the use of electrocautery. Methodology: A bibliographic search was carried out in the databases and indexes: Pubmed, Science Direct, Scopus, Proquest, Scielo, Schoolar Google. Original articles published between 2015-2020 were selected. For the extraction and synthesis of the content of the articles included, an Excel sheet was designed with the following variables: authors, title, year of publication, country and scientific journal; study objective, materials and methods, population and sampling, reported results. Results: A total of 121 articles were retrieved, of these 94 were excluded from the subsequent analysis due to the lack of appropriate data, the remaining 27 full-text studies met the inclusion and exclusion criteria set out in the study, which were included in the review. It was possible to establish that there are risks when inhaling electrocautery smoke that can trigger chronic respiratory pathologies such as lung cancer

Assessing the risk of viral infection from gases and plumes during intra-abdominal surgery: a systematic scoping review.

BackgroundThe aim of this study was to identify the current evidence regarding the risk of acquiring viral infections from gases or plumes during intra‐abdominal surgery. Peritoneal fluids may contain cellular material and virus particles. Electrocautery smoke and plumes from energy devices may aerosolize harmful substances and viral particles. Insufflation and desufflation during laparoscopic surgery may also aerosolize and distribute biological material. A systematic scoping review was performed to assess the evidence and inform safe surgical practice.MethodsA systematic search of the PubMed and Medline databases was undertaken until June 2020, observing Preferred Reporting Items for Systematic Reviews and Meta‐Analyses methodology, to identify articles associating viral infection of operating room staff from surgical gases and plumes. All evidence levels were included. The search strategy utilized the search terms ‘surgery’, ‘laparoscopy’, ‘laparoscopic’ ‘virus’, ‘smoke’, ‘risk’, ‘infection’.ResultsThe literature search identified 74 articles. Eight articles relevant to the subject of this review were included in the analysis, two of which specifically related to intra‐abdominal surgery. Of the remaining six, four involved gynaecological surgery and two were in‐vitro studies. No evidence that intra‐abdominal surgery was associated with an increased risk of acquiring viral infections from exsufflated gas or smoke plumes was identified.ConclusionThere is currently no evidence that respiratory viruses can be found in the peritoneal fluid. Whilst there is currently no evidence that desufflated carbon dioxide or surgical smoke plumes present a significant infectious risk, there is not a wealth of literature to inform current practice. Further clinical research in this area is required.

Easy-to-use electrocautery smoke evacuation device for open surgery under the risk of the COVID-19 pandemic.

ObjectiveThis study was performed to introduce an easy method of surgical smoke evacuation for patients with confirmed or suspected COVID-19 undergoing emergency surgery.MethodsAn easy, inexpensive, protective, and practical surgical smoke evacuation device/system was developed and is herein described.ResultsThe use of this surgical smoke evacuation device/system in open surgery is convenient and effective. It allows for easy, economic, useful, and protective surgical smoke evacuation.ConclusionsCOVID-19 infection causes direct mortality and morbidity, and its incidence has recently increased. Protection from electrosurgery-related smoke is recommended particularly during the current pandemic. This surgical smoke evacuation device/system is easy to use and provides a convenient and effective method of smoke evacuation during both open surgery and all cauterization interventions.

Evacuation of Electrocautery Smoke: Renewed Consideration During the COVID-19 Pandemic.

Evacuation of Electrocautery Smoke: Renewed Consideration During the COVID-19 Pandemic.

Analysis of electrocautery smoke released from the tissues frequently cut in orthopedic surgeries.

Electrosurgical smoke could be different by the device of cutting or the type of tissue that is being cut. To analyze the electrocautery smoke released from the tissues that are frequently cut in orthopedic surgeries. The released smoke from electrocautery of five different tissue types (meniscus, ligament, adipose, muscle, and synovium) of five patients who underwent total knee arthroplasty were collected and analyzed for volatile organic compounds (VOCs) and 27 candidate polycyclic aromatic hydrocarbons (n = 25). Surgical smoke was produced with an electrocautery device for 4 min. None of the 27 evaluated polycyclic aromatic hydrocarbons compounds were detectable in electrocautery smoke collected from the surgical cutting of the different tissues. The number and identity of detected VOCs were similar between the patients but not between tissue types. The number of detected VOCs was the highest in synovial tissue (n = 21) and the lowest in the meniscus and adipose tissue (n = 12). ‏The number of toxic and/or carcinogenic VOCs were the most in the muscle and meniscus tissues (Toluene, Ethylbenzene, and Styrene). No toxic and/or carcinogenic VOCs were identified in the ligament and adipose tissue. Meniscus and muscle tissue are associated with the highest number of toxic and/or carcinogenic VOCs. Therefore, we recommend that surgeons avoiding the electrocautery of these tissues.

Signs and symptoms related to inhalation of surgical smoke in the nursing team

ABSTRACT Objective: To compare the prevalence of signs and symptoms related to inhalation of surgical smoke among surgical technologists and non-surgical technologists nursing professionals. Method: A cross-sectional study with 46 professionals from a university hospital. To evaluate the prevalence, an instrument with signs/symptoms related to the inhalation of electrocautery smoke was used. To verify the comparison between the prevalence of signs/symptoms, the Fisher’s exact test was performed. Results: Higher prevalence of all signs/symptoms among surgical technologists, with a statistically significant difference between the act of instrumenting with the presence of at least one signs/symptoms related to inhalation of surgical smoke (p=0.01); eye irritation (p=0.02); irritation of nasal mucosa and oral cavity (p=0.03); headache (p=0.04). Conclusion: The presence of problems related to surgical smoke in nursing workers elicits more attention. Implications for practice: Health units must be aware of the risk of such exposure and take measures to preventing it.

Polycyclic aromatic hydrocarbons produced by electrocautery smoke and the use of personal protective equipment 1.

ABSTRACTObjective: analyze the concentration of polycyclic aromatic hydrocarbons in electrocautery smoke in operating rooms and the use of personal protective equipment by the intraoperative team when exposed to hydrocarbons.Method: exploratory and cross-sectional field research conducted in a surgery center. Gases were collected by a vacuum suction pump from a sample of 50 abdominal surgeries in which an electrocautery was used. A form was applied to identify the use of personal protective equipment. Gases were analyzed using chromatography. Descriptive statistics and Spearman's test were used to treat data.Results: there were 17 (34%) cholecystectomies with an average duration of 136 minutes, while the average time of electrocautery usage was 3.6 minutes. Airborne hydrocarbons were detected in operating rooms in 100% of the surgeries. Naphthalene was detected in 48 (96.0%) surgeries and phenanthrene in 49 (98.0%). The average concentration of these compounds was 0.0061 mg/m3 and a strong correlation (0.761) was found between them. The intraoperative teams did not use respirator masks such as the N95.Conclusion: electrocautery smoke produces gases that are harmful to the health of the intraoperative team, which is a concern considering the low adherence to the use of personal protective equipment.

Abstract 3977: iKnife: Rapid evaporative ionization mass spectrometry (REIMS) enables real-time chemical analysis of the mucosal lipidome for diagnostic and prognostic use in colorectal cancer

Abstract Background Real time electrospray ionization mass spectrometry (REIMS) enables detailed analysis of tumour lipid chemistry, based on real time analysis of electrocautery smoke plumes. Methods: This was a prospective, observational study performed at St. Mary's Hospital, London, UK. Patients undergoing elective surgical resections for colorectal cancer were recruited and fresh samples were analyzed ex-vivo using a typical electrosurgery hand piece and monopolar diathermy. Sampling was performed using cutting mode with a standard generator and 30W of output power (ValleylabTM). The hand piece was modified to allow aspiration of the electrosurgical aerosol to a Xevo G2-S iKnife QTof mass spectrometer (Waters Corporation). Raw mass spectrometric data were converted to imzML format (MSConvert) and imported into MATLAB (R2014a) for pre-processing. A prospective database of healthy, dysplastic and malignant colorectal tissues was built and multivariate analysis was performed using principal component analysis and linear discriminant analysis. Classification of each individual tissue type was performed using leave-one-patient-out cross-validation. Results 40 consecutive patients were recruited (22 male, median age 68y, range 47-90). Of the 23 tumor samples 10 were rectal adenocarcinoma and 13 colonic adenocarcinoma. TNM staging of the tumour samples was as follows: T2 (8), T3 (11) T4 (4), N0 (12), N1 (6) N2 (5), M0 (22), M1 (1). Distinction of healthy and malignant colorectal tissue for the whole data set demonstrated an overall classification accuracy of 94.4% and a sensitivity of 92.4%, Specificity 96.8% (ROC AUC 0.98). The diagnostic accuracy for dysplasia was 93.7% (Specificity 95.1%, sensitivity 85.7%, AUC 0.97). Increases in glycerophospholipids (p&amp;lt;0.0027), and triacylglycerols (p&amp;lt;0.0004) were seen in healthy mucosa and increased prostaglandin D2 expression was found in malignant tissue (p&amp;lt; 0.0002). Adenocarcinoma arising in the rectum could be differentiated from more proximal tumors with an overall accuracy of 87.3%. Short and long course chemotherapy modified the lipid signature. Anatomically discrete chemical analysis of rectal cancers was able to provide accurate descriptions of established histopathological and molecular markers of poor prognosis: nodal status (AUC 0.97), KRAS mutation (AUC 0.93) and extramural vascular invasion (EMV) (AUC 0.96). Conclusion REIMS chemical histology provides near real time diagnostic and prognostic information for stratifying oncological and surgical therapy. Citation Format: James Macalister Kinross, Laura Muirhead, James Alexander, Julia Balog, Cristina Guallar-Hoya, Abigail Speller, Ottmar Golff, Rob Goldin, Ara Darzi, Jeremy Nicholson, Zoltan Takats. iKnife: Rapid evaporative ionization mass spectrometry (REIMS) enables real-time chemical analysis of the mucosal lipidome for diagnostic and prognostic use in colorectal cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3977.

Cambios en la mucosa nasal de los médicos por exposición al humo por electrocoagulación

Objective: to prove that exposure to smoke resulting from electrocoagulation causes changes in the nasal mucosa of physicians in training at a public hospital in Mexico. Methodology: a prospective fixed cohort study was conducted with a working universe consisting of 43 physicians distributed as follows: a group of 20 professionals with non-surgical specialties (thus unexposed to electrocautery smoke inhalation), and another group of 23 with surgical specialties (thus they were exposed to electrocautery smoke inhalation). They underwent two nasal biopsies: one at the beginning of the study and another after training as specialists for four years. The biopsies were reviewed by the hospital’s chief of Pathology and the incidence of changes in the nasal mucosa in both groups was calculated together with exposure index and the relative risk. Results: the biopsies performed at baseline showed that none of the specialists in training included in this study had damages in the nasal mucosa. The final biopsies, performed after the four-year medical training, had the following results: 70% of the medical residents, who were exposed, showed some histopathological changes in the nasal mucosa (hyperplasia or squamous metaplasia), whereas only 5% (1/20) of the unexposed individuals had them; the risk factor for nasal mucosa damage by exposure was estimated at 13.8. The most common lesions resulting from exposure to smoke from electrocoagulation were hyperplasia and squamous metaplasia. Conclusions: our results demonstrate that residents exposed to smoke produced by electrocoagulation have changes in the nasal mucosa.

Composition of the electrocautery smoke: integrative literature review

To identify the composition of the smoke produced by electrocautery use during surgery. Integrative review with search for primary studies conducted in the databases of the US National Library of Medicine National Institutes of Health, Cumulative Index to Nursing and Allied Health Literature, and Latin American and Caribbean Health Sciences, covering the studies published between 2004 and 2014. The final sample consisted of 14 studies grouped into three categories, namely; polycyclic aromatic hydrocarbons, volatile compounds and volatile organic compounds. There is scientific evidence that electrocautery smoke has volatile toxic, carcinogenic and mutagenic compounds, and its inhalation constitutes a potential chemical risk to the health of workers involved in surgeries.

OC-102 A prospective, observational study of surgical and endoscopic rapid evaporative ionisation mass spectrometry (REIMS) for real time analysis of the colonic mucosal lipidome in colorectal cancer

Introduction REIMS permits real time analysis of tissue specific molecular information contained within an electrocautery smoke plume. 1 This study validated its diagnostic accuracy in colorectal cancer (CRC) and developed a novel endoscopic methodology. Method Patients undergoing elective surgery for CRC were recruited at St. Mary’s hospital London. 1. A standard electrosurgery handpiece using monopolar diatheramy on 30 W cutting mode (Valleylab TM ) was modified to allow aspiration of the electrosurgical aerosol to a Xevo G2-S iKnife QTof mass spectrometer (Waters Corporation). Ex-vivo analysis was performed and H&E staining and histological examination was carried out for validation. Multivariate analysis was performed using principal component analysis and linear discriminant analysis. Classification of each tissue type was performed using leave-one-patient-out cross-validation and receiver operating curves were generated. 2. Ex-vivo colorectal tissue was sampled using an endoscopic snare (Olympus Medical) modified to allow aspiration of the electrosurgical aerosol. Results 40 consecutive patients were recruited (22 male, median age 68 y, range 47–90). 23 tumour samples were analysed: 10 rectal adenocarcinomas and 13 colonic adenocarcinoma were analysed with TNM stages T2 (8), T3 (11) T4 (4), N0 (12), N1 (6) N2 (5), M0 (22), M1 (1). Distinction of malignant colorectal tissue was achieved with a classification accuracy of 94.4% and a sensitivity of 92.4%, Specificity 96.8% (ROC AUC 0.98). The diagnostic accuracy for dysplasia was 93.7% (Specificity 95.1%, sensitivity 85.7%, AUC 0.97). Distinction of tissue histology was possible based on membrane lipid ratios. Increases in glycerophospholipids (p = 0.0027), and triacylglycerols (p = 0.0004) were seen in healthy mucosa and increased prostaglandin D2 was found in malignant tissue (p = 0.0002). Endoscopic analysis was technically feasible and could identify colonic wall sub layers with a tissue classification accuracy of 88%. Discrimination of healthy colorectal tissue, adenomatous polyps and cancerous tissue (12 patients) was achieved with a tissue classification accuracy of 87.5%. Conclusion REIMS is able to diagnose dysplasia and malignant colorectal tissue with a high degree of accuracy in real time. This technology could improve the efficacy and safety of the endoscopic treatment of colon cancer. Disclosure of interest L. Muirhead: None Declared, J. Kinross Grant/ Research Support from: Imperial College BRC funding, Conflict with: Director of getwell media, R. Preece: None Declared, A. Speller: None Declared, O. Golf: None Declared, R. Goldin: None Declared, A. Darzi: None Declared, Z. Takats: None Declared. Reference Balog J, Sasi-Szabo L, Kinross J, et al . Intraoperative tissue identification using rapid evaporative ionization mass spectrometry. Sci Transl Med. 2013; 5 (194):194ra93

Síntomas respiratorios causados por el uso del electrocauterio en médicos en formación quirúrgica de un hospital de México

In order to determine the frequency of respiratory symptoms among residents from surgical specialties dures exposed to the electrocautery smoke, a cross-sectional study was conducted in February 2012. 50 third-year residents from different surgical specialties coming from a third-level hospital belonging to the Institute of Security and Social Services of the State Workers in Jalisco, Mexico, were included. The subject selection was non-probabilistic. A questionnaire on respiratory symptoms developed in Cuba was used for data collection. The most common symptoms were sensation of a lump in the throat (58%), and a sore throat (22%). The specialty with the highest rate of exposure was neurosurgery (24.1 min/surgical procedure). All, the physicians from this specialty had respiratory symptoms. We conclude that the cauterization smoke may be considered a risk for developing respiratory symptoms among physicians with surgical specialties.