Continuous Oral Suction Found to Reduce Aerosol in Esophagogastroduodenoscopy

Scene from a dentist’s office.
A team of investigators conducted a proof-of-concept study to determine if esophagogastroduodenoscopy is an aerosol-generating procedure and to identify methods for reducing the amount of aerosol generated.

Esophagogastroduodenoscopy (EGD) was determined to be an aerosol-generating procedure, and the use of dental suction may reduce the amount of aerosol generated, according to findings from a proof-of-concept, prospective observational study published in Gastroenterology.

All patients (N=93) undergoing EGD between May 7 and June 1, 2020, at the Prince of Wales Hospital in Hong Kong were recruited. EGD was performed using a 9.9-mm flexible video gastrointestinal scope while the patient was in the left lateral position with a mouthguard in place. A portable GT-526S Handheld Particle Counter was positioned within 10 cm from the patient’s mouth and was programmed to detect particles of 0.3, 0.5, 0.7, 1, 5, and 10 μm. All procedures were performed in a room that measured 37 m2, was maintained at 23±1°C and humidity ≤60%, and underwent 6 air changes per hour.

The patients underwent the procedure both unsedated (n=59) and sedated (n=34). Dental suction was used during the procedure for one-third of patients (n=30).

During all EGD procedures, the volume of particles of all sizes was found to increase significantly. However, procedures during which dental suction was used had significantly reduced number of particles when compared with baseline. The change in the log of particles per cubic feet before and during the procedure with a dental sucker were: -0.24 (95% CI, -0.32 to -0.16; P <.001) for 0.3 μm, -0.36 (95% CI, -0.50 to -0.22; P <.001) for 0.5 μm, -0.36 (95% CI, -0.56 to -0.16; P <.001) for 0.7 μm, -0.32 (95% CI, -0.57 to -0.07; P =.02) for 1 μm, -1.14 (95% CI, -1.92 to -0.36; P <.01) for 5 μm, and -0.71 (95% CI, -1.40 to -0.02; P =.046) for 10 μm. The use of dental suction caused the larger particles to have a smaller magnitude of increase during the procedure (5 μm; 1.35; t, 3.69; P <.01; 10 μm: 0.82; t, 2.78; P <.01).

EGD conducted without the use of dental suction were associated with significant increases in the log of particles per cubic feet when compared with baseline; specifically, particles 0.3 μm in size increased by 0.18 (t, 6.30; P <.01), 0.5 μm by 0.30 (t, 5.54; P <.01), 0.7 by 0.28 (t, 3.89; P <.01), 1 μm by 0.22 (t, 2.43; P =.02), 5 μm by 2.49 (t, 8.54; P <.01), and 10 μm by 1.53 (t, 6.03; P <.01).

Particle counts per cubic feet did not differ between individuals with or without sedation (P =.13 to P =.96).

A limitation of this study was the imbalance among patients who used and did not use dental suction.

The conclusions drawn from these data were that EGD is a procedure that generates aerosol. These results have important implications during the global pandemic, as all aerosol-generating procedures should be carefully assessed to reduce viral exposure for healthcare workers.

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Chan SM, Ma TW, Chong MK-C, Chan D L, Ng EKW, Chiu PWY. A proof of concept study: esophagogastroduodenoscopy is an aerosol-generating procedure and continuous oral suction during the procedure reduces the amount of aerosol generated [published online July 7, 2020]. Gastroenterology. doi:10.1053/j.gastro.2020.07.002