Aerosol generation through pars plana vitrectomy

Abstract

Purpose: To assess whether pars plana vitrectomy (PPV) is an aerosol-generating procedure (AGP) in an ex vivo experimental model.

Methods: In this ex vivo study on 10 porcine eyes, optical particle counter was used to measure particles ≤10 μm using cumulative mode in the six in-built channels: 0.3 μm, 0.5 μm, 1 μm, 2.5 μm, 5 μm and 10 μm aerosols during PPV. Two parts of the study were as follows: (1) to assess the pre-experimental baseline aerosol count in the theatre environment where there are dynamic changes in temperature and humidity and (2) to measure aerosol generation with 23-gauge and 25-gauge set-up. For each porcine eye, five measurements were taken for each consecutive step in the experiment including pre-PPV, during PPV, fluid-air exchange (FAX) and venting using a flute with 23-gauge set-up and a chimney with 25-gauge set-up. Therefore, a total of 200 measurements were recorded.

Results: With 23-gauge and 25-gauge PPV, there was no significant difference in aerosol generation in all six channels comparing pre-PPV versus PPV or pre-PPV versus FAX. Venting using flute with 23-gauge PPV showed significant reduction of aerosol ≤1 μm. Air venting using chimney with 25-gauge set-up showed no significant difference in aerosol of ≤1 μm. For cumulative aerosol counts of all particles measuring ≤5 μm, compared with pre-PPV, PPV or FAX, flute venting in 23-gauge set-up showed significant reduction unlike the same comparison for chimney venting in 25-gauge set-up.

Conclusion: PPV and its associate steps do not generate aerosols ≤10 μm with 23-gauge and 25-gauge set-ups.

Keywords: Infection; Microbiology; Vitreous.