Amount of contamination on the face shield of endoscopists during upper endoscopy between patients in two positions: A randomized study

The new 222-nm far ultraviolet-C lowers bacterial contamination to endoscopists during esophagogastroduodenoscopy

Objectives

This study aimed to clarify the disinfectant efficacy of the 222-nm far ultraviolet-C (UV-C) during esophagogastroduodenoscopy using bacterial cultures.

Methods

The endoscopists performed esophagogastroduodenoscopy wearing a gown with a tryptic soy agar medium plate on their epigastric region and were divided into two groups: 222-nm far UV-C irradiation (UV group) and non-UV irradiation (non-UV group). As a control group, tryptic soy agar medium plates were placed about 110 cm above the floor. The incidence of bacterial contamination was determined by positive bacterial culture. The cultured bacteria were identified by 16S rRNA sequencing. Additionally, the actual UV exposure dose was measured using the UV-indicator card which changed colors upon exposure to 222 nm far UV-C.

Results

The bacterial culture positivity in the UV group (5.03%) was significantly lower than that in the non-UV group (25.76%), p < 0.0001. Most of the bacteria identified in the UV and non-UV groups were normal constituents of the oral flora, including Streptococcus salivarius and Staphylococci. Conversely, pathogenic microbes were found in the control group. The actual exposure doses of 222-nm far UV-C at the endoscopists' face, neck, and epigastric region were 2.09 ± 0.29, 5.89 ± 0.49, and 7.36 ± 0.58 mJ/cm2, respectively.

Conclusions

The 222-nm far UV-C irradiation reduced bacterial contamination for endoscopists. It can be used with conventional physical coverings to provide more effective infection control.

Bacterial contamination of endoscopist and assistant face visors during gastrointestinal endoscopy: a pilot study

Background and aim

During the COVID-19 pandemic, health workers' facial exposure to pathogens has been brought into focus. In this study, we aimed to determine the occurrence and degree of facial contamination to both endoscopists and their assistants during endoscopic procedures to help inform future safety measures.

Methods

Non-sterile visors worn by endoscopist, assistant and room control visors from 50 procedures were swabbed post procedure for culture. Procedure type, therapy, duration and evidence of visible visor contamination were recorded. After 48-hour incubation, all bacterial colonies were identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Organisms were classified into skin/environmental, oronasal and enteric.

Results

A total of 104 visors were available for assessment (93 staff; 11 control). In worn visors, skin/environmental flora were isolated from 70, oronasal flora from 8, and enteric flora from 3 with an average colony count of >9.5. Notably, bacteria of enteric origin (Escherichia coli and Enterobacter cloacae) were isolated from three worn visors. In room control, skin/environmental flora were isolated from seven and oronasal flora from one with average colony count of five. No room control visors grew enteric flora. Overall, 9.1% room control and 10.8% worn visors were contaminated with organisms that could possibly have originated from patients. However, enteric flora were only obtained from worn visors. No visors were visibly contaminated.

Conclusion

This pilot study demonstrates risk of contamination to faces of endoscopists and assistants. Larger studies are required to determine degree of risk and to give guidance on facial protection during gastrointestinal endoscopy.

Does an Extraoral Suction Device Reduce Aerosol Generation and Prevent Droplet Exposure to the Examiner during Esophagogastroduodenoscopy?

Esophagogastroduodenoscopy (EGD) is an aerosol-generating procedure. A major challenge in the COVID-19 era is how to prevent the spread of aerosols and droplets in endoscopic units. We evaluated the effectiveness of an extraoral suction device in preventing indoor aerosol diffusion and droplet exposure for examiners. The study involved 61 patients who underwent EGD at our institution from 1 February to 31 March 2022. To determine whether aerosol spread increases before or after EGD examination with an extraoral suction device located in front of the patient’s mouth, aerosols of 0.3, 0.5, 1, 3, 5, and 10 μm were measured with a handheld particle counter. The degree of contamination of the plastic gowns on the examiners was assessed using the rapid adenosine triphosphate test. The extraoral suction device significantly reduced the diffusion of large particles (3, 5, and 10 μm) after finishing the EGD examination. However, the diffusion of small particles (0.3 and 0.5 μm) was significantly increased. This extraoral suction device was effective in reducing large particle diffusion during EGD examination but was limited for minimizing small particle diffusion or droplet exposure to the examiner.

The comparison of aerosol exposures to endoscopy personnel performing diagnostic upper gastrointestinal endoscopy in patients with and without head box: A randomized control trial

BACKGROUND AND AIMS

Esophagogastroduodenoscopy (EGD) has been identified as an aerosol-generating procedure (AGP) during the COVID-19 pandemic. The risk of AGP and benefits of utilizing protective measures have never been fully studied.

METHODS

A randomized control, open-label study in patients scheduled for diagnostic EGD between September and December 2021 was conducted. Patients were randomly assigned to either head box group or without head box group (control group). Particles were measured with six-size particle counters at the nurse anesthetist and endoscopist position. Primary composite outcomes were the mean difference of aerosol particle levels during and before EGD at the nurse anesthetist face position and at the endoscopist face position. Secondary outcomes were factors increasing aerosol particle levels and safety of the head box.

RESULTS

From 196 enrolled patients, 190 were analyzed. Baseline characteristics were not different between the two groups. The mean distance between endoscopist face and patient mouth was 67.2 ± 4.9 cm. The mean differences of 0.3-, 0.5-, and 1.0-μm particles during the procedure and at baseline before the procedure at nurse anesthetist position and the mean differences of 0.3-μm particles at the endoscopist position was found to have decreased in the head box group and increased in the control group (P < 0.001, 0.001, 0.014, and P < 0.001, respectively). Cough, burping, and body movement increased aerosol particles. No additional adverse events were observed in the head box group.

CONCLUSIONS

EGD with the head box is safe and can reduce significant aerosolization to endoscopy personnel including nurse anesthetists and endoscopists.

Bacterial exposure risk to the endoscopist's face while performing endoscopy

Objectives

Gastrointestinal endoscopy increases the risk of bacterial exposure to endoscopists. However, before 2019, most endoscopists did not pay attention to microorganism transmission from patients. This study aimed to investigate the incidence of bacterial exposure to endoscopists' faces during gastrointestinal endoscopic procedures using the bacterial culture method.

Methods

This was a single-centered, retrospective study including endoscopists who performed various gastrointestinal endoscopy procedures at the Division of Endoscopy, Hirosaki University Hospital between August 31 and October 6, 2020. Endoscopists wore surgical masks and affixed pre-sterilized films over them. Following the gastrointestinal endoscopic procedures, attached microbes were collected from the endoscopists' surface films using sterilized swabs. Collected microorganisms were cultured on tryptic soy agar and 5% sheep blood agar, and the incidence of bacterial exposure was determined by bacterial culture positivity. Cultured bacteria were identified by gram staining and 16S rRNA gene sequencing.

Results

Bacterial culture positivity was 12.6%, and it was significantly higher in therapeutic than in diagnostic endoscopy. Notably, therapeutic endoscopy increased bacterial culture positivity in colonoscopy, but not in esophagogastroduodenoscopy. Staphylococci, including Staphylococcus epidermidis and Staphylococcus capitis, were the most commonly found bacteria in samples identified through 16S rRNA gene sequencing.

Conclusions

The risk of bacterial exposure to the endoscopist's face was increased in colonoscopy treatment procedures. Therefore, endoscopists should be aware of the significant risk of microbial infection from scattering fluid that comes from the endoscopy's working channel.

Clinical Efficacy of Novel Patient-Covering Negative-Pressure Box for Shielding Virus Transmission during Esophagogastroduodenoscopy: A Prospective Observational Study

Esophagogastroduodenoscopy (EGD) has a high risk of virus transmission during the current coronavirus disease 2019 era, and preventive measures are under investigation. We investigated the effectiveness of a newly developed patient-covering negative-pressure box system (Endo barrier^®) (EB) for EGD. Eighty consecutive unsedated patients who underwent screening EGD with EB use were prospectively enrolled. To examine the aerosol ratio before, during, and after EGD, 0.3- and 0.5-μm aerosols were measured every 60 s using an optical counter. Moreover, the degree of contamination of the examiners’ goggles and vinyl gowns was assessed before and after EGD using a rapid adenosine triphosphate (ATP) test for simulated droplets. Data were available in 73 patients and showed that 0.3- and 0.5-μm particles did not increase in 95.8% (70/73) and 94.5% (69/73) of patients during EGD under EB. There were no significant differences in the total 0.3- or 0.5-μm particle counts before versus after EGD. The difference in the ATP levels before and after EGD was −0.6 ± 16.6 relative light units (RLU) on goggles and 1.59 ± 19.9 RLU on gowns (both within the cutoff value). EB use during EGD may provide a certain preventive effect against aerosols and droplets, decreasing examiners’ exposure to viruses.