Activated carbon fiber filters could reduce the risk of surgical smoke exposure during laparoscopic surgery: application of volatile organic compounds.

BACKGROUND: Generation of smoke is inevitable during surgical procedures. Some volatile organic compounds (VOCs) in surgical smoke are known to be strong carcinogens. We used a prototype of a multi-layered complex filter in an attempt to eliminate VOCs. METHODS: From June 2015 to July 2015, 20 patients underwent transperitoneal laparoscopic nephrectomy for renal cell carcinoma. Smoke (pre-filter) was collected 20 min after the electrocautery device was first used during the surgery, by the direct collection method, with a 5-L Tedlar® gas-sampling bag. Twenty and 120 min after the filter was applied, smoke (post-filter) was again collected using the same method. The sample was analyzed by gas chromatography and mass spectrography. The cancer risk and hazard quotient were analyzed based on US Environmental Protection Agency guidelines. RESULTS: Twenty patients with a median age of 54.5 (30-80) years were enrolled in the study. Eighteen VOCs were detected using the Japanese indoor air standards mix analysis. The total elimination rate of the VOCs was 86.49 ± 2.83%. The post-filter (120 min) cancer risk (mean ± standard deviation) reduced to a negligible level for benzene, ethylbenzene, and styrene except 1,2-dichloroethane. The post-filter (120 min) hazard quotient for each compound decreased to levels posing a negligible risk for acetone, hexane, benzene, toluene, p-xylene, o-xylene, and styrene. CONCLUSION: Strong carcinogens, such as 1,2-dichloroethane, benzene, and ethylbenzene, were eliminated by more than 85% by using this activated carbon fiber filter and the risks from these compounds decreased to an almost negligible level. We suggest using every measure, including these filters, to protect the health of operating room personnel.

Multi-zone simulation of outdoor particle penetration and transport in a multi-story building.

In areas with poor ambient air quality, indoor particle concentrations can be significantly affected by particulate matter originating outdoors. The indoor environments of multi-zone and multi-story buildings are affected differently by outdoor particles compared with single-family houses, because of the buildings' more complicated airflow characteristics. The objective of this study is to analyze outdoor particle penetration and transport, and their impact on indoor air, in a multi-zone and multi-story building using a CONTAMW simulation. For the airflow and particle transport analysis, the building leakage, penetration coefficients, and deposition rates were determined by on-site experiments. The results of airflow simulations for cold winters show that outdoor air infiltrates through the lower part of building and exfiltrates from the upper part. The results of the particle simulation also indicated that the airflow characteristics, combined with deposition rates, cause the lower floors of a multi-story building to be exposed to higher fine particle concentrations compared with the upper floors of the building. The study demonstrated that the CONTAMW simulation can be useful in analyzing the impact of outdoor particles on indoor environments through the identification of key particle transport parameters and validated airflow simulations.

Staged protocol in treatment of open distal tibia fracture: using lateral MIPO.

BACKGROUND: To evaluate the radiological, clinical results in patients with open distal tibia factures, who were treated with a staged treatment protocol using the lateral minimally invasive plate osteosynthesis (MIPO) technique. METHODS: From January 2007 to June 2009, 10 patients with open distal tibia fractures (Gustilo-Anderson classification II, 3; IIIA, 1; IIIB, 6) were treated using a staged treatment protocol. The initial debridement and application of an external fixator were performed within 24 hours and the mean interval from injury to definitive surgical treatment was 15 days (range, 6 to 52 days). Eight weeks later, an additional bone graft was performed in 3 patients. The follow-up duration was more than 1 year. RESULTS: The mean fracture healing time was 21 weeks (range, 17 to 28 weeks), and the average Iowa ankle rating score was 84.5 points. At the last follow-up, there was no non-union, angular deformity > 5°, shortening > 10 mm or infection. In 10 patients, 2 patients had a superficial wound infection, and another 2 patients showed limitation of ankle joint motion. CONCLUSIONS: This staged treatment protocol using a lateral MIPO technique is a useful alternative method for achieving high functional recovery with good healing and low complication rates in patients with an open distal tibia fracture.