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Published on: February 12, 2021
Surgical masks as source of bacterial contamination during operative procedures
Liu Zhiqing1, Chang Yongyun1, Chu Wenxiang1
1Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, People's Republic of China.
Background:
Surgical masks (SMs) are used to reduce bacterial shedding from the mouth, nose and face. This study aimed to investigate whether SMs may be a potential source of bacterial shedding leading to an increased risk of surgical site infection.
Methods:
Bacterial contamination of the SMs was tested by making an impression of the external surface of the mask on sterile culture media immediately. We investigated the difference in bacterial counts between the SMs worn by surgeons and those placed unused in the operating room (OR), and the bacterial count variation with indicated wearing time. Moreover, the difference in bacterial counts on the external surface between the first and second layers of double-layered SMs was also assessed.
Results:
The bacterial count on the surface of SMs increased with extended operating times; significant difference was found between the 4- to 6-hour and 0-hour groups (p < 0.05). When we analysed the bacterial counts from the same surgeon, a significant increase was noted in the 2-hours group. Moreover, the bacterial counts were significantly higher among the surgeons than the OR. Additionally, the bacterial count of the external surface of the second mask was significantly higher than that of the first one.
Conclusions:
The source of bacterial contamination in SMs was the body surface of the surgeons rather than the OR environment. Moreover, we recommend that surgeons should change the mask after each operation, especially those beyond 2 hours. Double-layered SMs or those with excellent filtration function may also be a better alternative.
The Translational Potential Of This Article:
This study provides strong evidence for the identification that SMs as source of bacterial contamination during operative procedures, which should be a cause for alarm and attention in the prevention of surgical site infection in clinical practice.
Insights
Surgical masks (SMs) can become contaminated by surgeons, increasing bacterial shedding. Masks should be changed after 2 hours or each operation to prevent surgical site infections.
Area of Science:
- Microbiology
- Infectious Disease Prevention
- Surgical Safety
Background:
- Surgical masks (SMs) are utilized to minimize bacterial shedding from the face.
- Concerns exist regarding SMs potentially contributing to bacterial shedding and increasing surgical site infection (SSI) risk.
Purpose of the Study:
- To investigate if SMs serve as a source of bacterial shedding.
- To determine the impact of wearing time and environment on mask bacterial contamination.
- To assess bacterial contamination on different layers of double-layered SMs.
Main Methods:
- Bacterial contamination on SMs was assessed using sterile culture media impressions.
- Compared bacterial counts on SMs worn by surgeons versus unused masks in the operating room (OR).
- Analyzed bacterial counts based on mask wearing duration and mask layer.
Main Results:
- Bacterial counts on SMs increased significantly with longer wearing times (4-6 hours vs. 0 hours).
- Bacterial contamination was significantly higher on SMs worn by surgeons compared to unused masks in the OR.
- The outer layer of double-layered SMs showed higher bacterial counts than the inner layer.
Conclusions:
- Surgeons' body surfaces are the primary source of SM bacterial contamination, not the OR environment.
- Recommend changing surgical masks after each operation, especially after 2 hours of use.
- Consider double-layered masks or those with enhanced filtration for improved bacterial containment.
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