Measurement of particulate matter 2.5 in surgical smoke and its health hazards.

PURPOSE: Surgical smoke is generated during the cauterization, coagulation, and incision of biological tissues by electrocautery, ultrasonic coagulation, incising devices, and lasers. Surgical smoke comprises water, water vapor, steam, and some particulate matter, including bacteria, viruses, cell fragments, and volatile organic compounds, which can pose health risks to the operating room personnel. In this study, we measured the concentration of particulate matter 2.5 (particles with a diameter of ≤ 2.5 µm) in surgical smoke. METHODS: We used digital dust counters for real-time monitoring of particulate matter 2.5 generated intraoperatively in breast and gastrointestinal surgeries performed at our hospitals between 2019 and 2020. RESULTS: Concentrations of particulate matter 2.5 were measured in surgical smoke generated when performing 14 different surgeries. Immediately after electrocautery, the concentration of particulate matter 2.5 increased to 2258 µg/m3 and then, when we stopped using the devices, it decreased rapidly to the initial levels. Interestingly, the concentrations increased after each intermittent electrocautery procedure. Higher concentrations of particulate matter 2.5 were observed during breast surgeries than during laparoscopic procedures. CONCLUSION: Surgical smoke poses potential health risks to operating room personnel by contaminating their breathing zone with high concentrations of particulate matter 2.5. A local exhaust ventilation system is needed to reduce exposure.

Haemostatic devices in parotid surgery: a systematic review.

OBJECTIVE: The Harmonic Scalpel and Ligasure (Covidien) devices are commonly used in head and neck surgery. Parotidectomy is a complex and intricate surgery that requires careful dissection of the facial nerve. This study aimed to compare surgical outcomes in parotidectomy using these haemostatic devices with traditional scalpel and cautery. METHOD: A systematic review of the literature was performed with subsequent meta-analysis of seven studies that compared the use of haemostatic devices to traditional scalpel and cautery in parotidectomy. Outcome measures included: temporary facial paresis, operating time, intra-operative blood loss, post-operative drain output and length of hospital stay. RESULTS: A total of 7 studies representing 675 patients were identified: 372 patients were treated with haemostatic devices, and 303 patients were treated with scalpel and cautery. Statistically significant outcomes favouring the use of haemostatic devices included operating time, intra-operative blood loss and post-operative drain output. Outcome measures that did not favour either treatment included facial nerve paresis and length of hospital stay. CONCLUSION: Overall, haemostatic devices were found to reduce operating time, intra-operative blood loss and post-operative drain output.

Quantifying Viral Particle Aerosolization Risk During Tracheostomy Surgery and Tracheostomy Care.

Importance: During respiratory disease outbreaks such as the COVID-19 pandemic, aerosol-generating procedures, including tracheostomy, are associated with the risk of viral transmission to health care workers. Objective: To quantify particle aerosolization during tracheostomy surgery and tracheostomy care and to evaluate interventions that minimize the risk of viral particle exposure. Design, Setting, and Participants: This comparative effectiveness study was conducted from August 2020 to January 2021 at a tertiary care academic institution. Aerosol generation was measured in real time with an optical particle counter during simulated (manikin) tracheostomy surgical and clinical conditions, including cough, airway nebulization, open suctioning, and electrocautery. Aerosol sampling was also performed during in vivo swine tracheostomy procedures (n = 4), with or without electrocautery. Fluorescent dye was used to visualize cough spread onto the surgical field during swine tracheostomy. Finally, 6 tracheostomy coverings were compared with no tracheostomy covering to quantify reduction in particle aerosolization. Main Outcomes and Measures: Respirable aerosolized particle concentration. Results: Cough, airway humidification, open suctioning, and electrocautery produced aerosol particles substantially above baseline. Compared with uncovered tracheostomy, decreased aerosolization was found with the use of tracheostomy coverings, including a cotton mask (73.8% [(95% CI, 63.0%-84.5%]; d = 3.8), polyester gaiter 79.5% [95% CI, 68.7%-90.3%]; d = 7.2), humidification mask (82.8% [95% CI, 72.0%-93.7%]; d = 8.6), heat moisture exchanger (HME) (91.0% [95% CI, 80.2%-101.7%]; d = 19.0), and surgical mask (89.9% [95% CI, 79.3%-100.6%]; d = 12.8). Simultaneous use of a surgical mask and HME decreased the particle concentration compared with either the HME (95% CI, 1.6%-12.3%; Cohen d = 1.2) or surgical mask (95% CI, 2.7%-13.2%; d = 1.9) used independently. Procedures performed with electrocautery increased total aerosolized particles by 1500 particles/m3 per 5-second interval (95% CI, 1380-1610 particles/m3 per 5-second interval; d = 1.8). Conclusions and Relevance: The findings of this laboratory and animal comparative effectiveness study indicate that tracheostomy surgery and tracheostomy care are associated with significant aerosol generation, putting health care workers at risk for viral transmission of airborne diseases. Combined HME and surgical mask coverage of the tracheostomy was associated with decreased aerosolization, thereby reducing the risk of viral transmission to health care workers.

Aerosol and droplet generation from orbital repair: Surgical risk in the pandemic era.

INTRODUCTION: The highly contagious COVID-19 has resulted in millions of deaths worldwide. Physicians performing orbital procedures may be at increased risk of occupational exposure to the virus due to exposure to secretions. The goal of this study is to measure the droplet and aerosol production during repair of the inferior orbital rim and trial a smoke-evacuating electrocautery handpiece as a mitigation device. MATERIAL AND METHODS: The inferior rim of 6 cadaveric orbits was approached transconjunctivally using either standard or smoke-evacuator electrocautery and plated using a high-speed drill. Following fluorescein inoculation, droplet generation was measured by counting under ultraviolet-A (UV-A) light against a blue background. Aerosol generation from 0.300-10.000 µm was measured using an optical particle sizer. Droplet and aerosol generation was compared against retraction of the orbital soft tissue as a negative control. RESULTS: No droplets were observed following the orbital approach using electrocautery. Visible droplets were observed after plating with a high-speed drill for 3 of 6 orbits. Total aerosol generation was significantly higher than negative control following the use of standard electrocautery. Use of smoke-evacuator electrocautery was associated with significantly lower aerosol generation in 2 of 3 size groups and in total. There was no significant increase in total aerosols associated with high-speed drilling. DISCUSSION AND CONCLUSIONS: Droplet generation for orbital repair was present only following plating with high-speed drill. Aerosol generation during standard electrocautery was significantly reduced using a smoke-evacuating electrocautery handpiece. Aerosols were not significantly increased by high-speed drilling.