Sussex Eye Hospital, Brighton and Sussex University Hospitals NHS Trust, Brighton, UK.
Brighton and Sussex Medical School, Brighton, UK.
Br J Ophthalmol. 2021 Sep;105(9):1313-1317. doi: 10.1136/bjophthalmol-2020-317214. Epub 2020 Oct 14.
To assess whether pars plana vitrectomy (PPV) is an aerosol-generating procedure (AGP) in an ex vivo experimental model.
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.
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.
PPV and its associate steps do not generate aerosols ≤10 μm with 23-gauge and 25-gauge set-ups.
在体外实验模型中评估经平坦部玻璃体切除术（PPV）是否为气溶胶产生程序（AGP）。
在这项对 10 只猪眼的体外研究中，使用光学粒子计数器，采用累积模式，在 6 个内置通道中测量粒径≤10μm 的颗粒：0.3μm、0.5μm、1μm、2.5μm、5μm 和 10μm 气溶胶，期间行 PPV。研究分为两部分：（1）评估术中环境的实验前基础气溶胶计数，术中环境中温度和湿度动态变化；（2）使用 23 号和 25 号设置测量气溶胶生成。对于每只猪眼，每个实验步骤（包括 PPV 前、PPV 期间、气液交换（FAX）和使用 23 号设置的长笛以及使用 25 号设置的烟囱通风）连续测量 5 次。因此，共记录了 200 次测量。
与 23 号和 25 号 PPV 相比，在所有六个通道中，与 PPV 或 FAX 相比，在预 PPV 与 PPV 或预 PPV 与 FAX 之间，气溶胶生成无显著差异。使用 23 号设置的长笛通风，≤1μm 的气溶胶显著减少。使用 25 号设置的烟囱进行空气通风，≤1μm 的气溶胶无显著差异。对于所有测量的≤5μm 的颗粒的累积气溶胶计数，与预 PPV、PPV 或 FAX 相比，23 号设置的长笛通风显示出显著减少，而对于 25 号设置的烟囱通风，相同的比较则无显著差异。
与 23 号和 25 号设置相比，PPV 及其相关步骤不会产生≤10μm 的气溶胶。
