According to the working principle of the upper-level flat jet UV light air disinfector, the machine is installed in the upper part of the room and the UV irradiation is located in the upper area, while the lower part is relatively UV-free to ensure that it does not come into contact with indoor personnel. The pathogens in the upper air are killed and lose their ability to reproduce and form colonies Due to the temperature difference indoor air forms slow convection, the lower space air containing pathogens in the lower space continuously enters the upper UV zone, thus The air in the lower space contains pathogens that continuously enter the upper UV zone, thus disinfecting all the air in the room.
In this study, the ozone concentrations in the test and control groups were well below the upper safety limit. Below the upper safety limit, confirming that the machine does not pose a threat to the health of the indoor, confirms that the machine does not pose a health risk to the health care workers in the room. However, there was no statistical difference in the total number of bacteria in the air of the two groups. However, there was no statistical difference in the total number of colonies in the air between the two groups. There was also no statistical difference in the number of colonies in the air between the two groups at 1, 2, and 5 h after the start of surgery. It could not be confirmed that the upper-level flat UV The advantage of the upper-level flat UV light air disinfector in reducing the number of airborne colonies could not be confirmed.
Further analysis revealed that with increasing sampling time, the number of airborne colonies in the test and the control group showed an increasing trend in the number of airborne colonies, with a strong correlation between the two. There was a strong correlation between the two. This indicates that even with the continuous disinfection of the upper level of flat UV radiation, the number of airborne bacteria increased after 5 h. The number of colonies in the air continued to increase after 5 h. When the number of medical personnel in the operating room was used as the variable, the results of the study showed that the number of colonies in the air continued to increase as the number of medical personnel in the operating room increased. Showed that the number of colonies in the air increased with the increase in the number of personnel in the test and control groups. There was a significant correlation between the increase in the number of airborne colonies and the increase in the number of medical personnel in the operating room. It is suggested that controlling the number of personnel is the most effective way to ensure clean air in the operating room. The number of personnel is an important measure to ensure clean air in the operating room. In this study In this study, when air sampling was conducted, the samples monitored in the occupied room In this study, the samples monitored in the occupied room failed to pass the test; while in the unoccupied room, the sample passing rate was 76.92%, which also This indicates the need to control the number of personnel.
The cleanliness of the operating room air has long been considered to be closely related to SSI. Air cleanliness techniques are thought to reduce the number of pathogenic microorganisms in the operating room air, thereby preventing and controlling possible surgical site infections during surgery. The SSI Prevention Guidelines published by the CDC in 1999 suggested that laminar flow technology could be used to reduce SSI, and its updated version in 2017 does not explicitly recommend this technology. A systematic analysis of a large sample of literature also recommends that surgical technique remains a key factor influencing incisional infections. 2019 Chinese Surgical Site Infection Prevention Guidelines recommend bowel preparation, antimicrobial drug use, surgical hand disinfection, maintenance of body temperature, perioperative glycemic control, and antimicrobial-coated sutures, again air-cleaning techniques such as laminar flow were not emphasized.
A Meta-analysis by Bischoff et al. showed that clean air techniques such as laminar flow did not reduce the risk of deep surgical site infections after total hip and total knee arthroplasty compared with general operating room ventilation; nor did they have a beneficial effect on the risk of surgical site infections after abdominal and vascular surgery. In contrast to costly laminar flow systems, a combination of systemic antimicrobial drugs and antimicrobial-coated sutures under conventional ventilation in general operating rooms can provide the greatest benefit to patients and cost savings to hospitals.
The results of this trial also support the above-mentioned view that prevention of surgical site infections should not focus only on on-air disinfection. Without a reasonable reduction in operating time and regulation of the number of medical and nursing staff entering the operating room, even with the use of upper-level flat-light UV light air disinfection, its benefit in controlling SSI is still limited. The effective implementation of comprehensive preventive measures for SSI control and the judicious use of other air-cleaning technologies, such as upper-level UV light air disinfection, can help to reduce patient suffering and treatment costs, which is a direction that is constantly being explored by sensory control staff and clinicians.