ABSTRACT
Ozone is a highly oxidizing gas easily generated from atmospheric oxygen with inexpensive equipment and is commonly used for the disinfection of municipal water, foods, and surfaces. We report tests of the ability of ozone to inactivate enveloped respiratory viruses (influenza A virus and respiratory syncytial virus), chosen as more easily handled surrogates for SARS-CoV-2, on N95 respirators and other personal protective equipment (PPE) commonly used in hospitals. At 20 ppm, an ozone concentration easily achieved by standard commercial equipment, the viruses were inactivated with high efficiency as long as the relative humidity was above a threshold value of approximately 50%. In the absence of humidity control, disinfection is more variable and requires considerably longer exposure under relatively dry conditions. This report extends the observations of a previous publication (http://doi.org/10.1080/01919510902747969) to hospital-relevant materials and provides additional details about the relationship of humidity to the antiviral activity of ozone. Home CPAP disinfection devices using ozone can provide effective results for individuals. Ozone did not appear to degrade any of the materials tested except for elastic bands if strained during treatment (such as by the pressure exerted by stapled attachment to N95 respirators). The filtration efficiency of N95 respirator material was not compromised. Overall, we recommend exposures of at least 40 minutes to 20 ppm ozone and >70% relative humidity at ambient temperatures (21-24{degrees}C) for 4-log (99.99%) reduction of viral infectivity on a variety of PPE, including gowns, face shields, and respirators. Shorter exposure times are likely to be effective under these conditions, but at the risk of some variability for different materials. Higher ozone concentrations and higher humidity levels promoted faster inactivation of viruses. Our work suggests that ozone exposure can be a widely accessible method for disinfecting PPE, permitting safer re-use for healthcare workers and patients alike in times of shortage.
ABSTRACT
Objective To investigate the safety and feasibility of the modified terminal cannula ileostomy in laparoscopic anus-preserving operation of low rectal cancer (RC).Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 15 patients who underwent laparoscopic radical resection of RC + terminal cannula ileostomy in the Subei People's Hospital of Jiangsu Province between September 2016 and June 2017 were collected.The patients underwent laparoscopic low anterior resection of RC,intra-abdominal sigmoid colon-rectum end-to-end anastomosis after extracting tumor specimens,and terminal cannula ileostomy in vitro.Observation indicators:(1) intraoperative situations:operation time,time of cannula ileostomy,volume of intraoperative blood loss,number of lymph node dissected,surgical margin;(2) postoperative situations:time to initial anal exsufflation,recovery time of defecation,time of tube removal,closing time of stoma,postoperative complications,duration of hospital stay;(3) follow-up situations.Follow-up using outpatient examination and telephone interview was performed to detect the anastomotic leakage-related complications up to December 2017.Measurement data with normal distribution were represented as (x)±s.Results (1) Intraoperative situations:all the 15 patients underwent successful laparoscopic radical resection of RC + terminal cannula ileostomy,without conversion to open surgery and death.The operation time,time of cannula ileostomy,volume of intraoperative blood loss and number of lymph node dissected were respectively (170 ± 34) minutes,(23 ± 4) minutes,(59 ± 27)mL and (13 ± 5) per case.No residual cancer cells were found in resection margins.(2) Postoperative situations:time to initial anal exsufflation and recovery time of defecation in 15 patients were respectively (6± 1) days and (7 ± 1) days.The stoma was automatically closed after tube removal,and time of tube removal and closing time of stoma after tube removal were respectively (23 ± 2) days and (3 ± 1) days.The incidence of postoperative complications was 1/15.One patient with catheterization-related complications was improved by strengthening dressing and antibiotic use,and the stoma was healed at 8 days after tube removal.There was no anastomotic leakage-related complications and death.The duration of hospital stay was (15±3) days.(3) Followup situations:all the 15 patients were followed up for 6-12 months.During the follow-up,there were no anastomotic leakage-related complications and death.Conclusion The modifyied terminal cannula ileostomy is safe and feasible,and is also an ideal surgical method for preventing anastomotic leakage in the laparoscopic anuspreserving operation of low RC.
