Many guidelines consider supraglottic airway use to be an aerosol-generating procedure. This status requires increased levels of personal protective equipment, fallow time between cases and results in reduced operating theatre efficiency. Aerosol generation has never been quantitated during supraglottic airway use. To address this evidence gap, we conducted real-time aerosol monitoring (0.3–10-µm diameter) in ultraclean operating theatres during supraglottic airway insertion and removal. This showed very low background particle concentrations (median (IQR [range]) 1.6 (0–3.1 [0–4.0]) particles.l⁻¹) against which the patient’s tidal breathing produced a higher concentration of aerosol (4.0 (1.3–11.0 [0–44]) particles.l⁻¹, p = 0.048). The average aerosol concentration detected during supraglottic airway insertion (1.3 (1.0–4.2 [0–6.2]) particles.l⁻¹, n = 11), and removal (2.1 (0–17.5 [0–26.2]) particles.l⁻¹, n = 12) was no different to tidal breathing (p = 0.31 and p = 0.84, respectively). Comparison of supraglottic airway insertion and removal with a volitional cough (104 (66–169 [33–326]), n = 27), demonstrated that supraglottic airway insertion/removal sequences produced <4% of the aerosol compared with a single cough (p < 0.001). A transient aerosol increase was recorded during one complicated supraglottic airway insertion (which initially failed to provide a patent airway). Detailed analysis of this event showed an atypical particle size distribution and we subsequently identified multiple sources of non-respiratory aerosols that may be produced during airway management and can be considered as artefacts. These findings demonstrate supraglottic airway insertion/removal generates no more bio-aerosol than breathing and far less than a cough. This should inform the design of infection prevention strategies for anaesthetists and operating theatre staff caring for patients managed with supraglottic airways.

中文翻译：

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声门上气道插入和移除过程中气溶胶产生的定量评估


许多指南认为声门上气道的使用是一种产生气溶胶的过程。这种状态需要增加个人防护装备的水平、病例之间的休整时间，并导致手术室效率降低。声门上气道使用过程中气溶胶的产生从未被定量过。为了解决这一证据差距，我们在超净手术室中进行声门上气道插入和移除过程中进行实时气溶胶监测（直径 0.3-10 µm）。这表明背景颗粒浓度非常低（中位数（IQR [范围]）1.6（0–3.1 [0–4.0]）颗粒.l ^-1 ），而患者的潮式呼吸产生了更高浓度的气溶胶（4.0（1.3–11.0） [0–44]) 粒子.l ⁻¹ , p = 0.048)。声门上气道插入 (1.3 (1.0–4.2 [0–6.2]) 颗粒.l ⁻¹ , n = 11) 和移除 (2.1 (0–17.5 [0–26.2]) 颗粒.l ⁻期间检测到的平均气溶胶浓度¹ ，n=12）与潮式呼吸没有区别（分别为p=0.31和p=0.84）。声门上气道插入和移除与自主咳嗽的比较（104（66-169 [33-326]），n = 27）表明，与单次咳嗽相比，声门上气道插入/移除序列产生的气溶胶<4%（ p < 0.001）。在一次复杂的声门上气道插入过程中记录到短暂的气溶胶增加（最初未能提供开放的气道）。对该事件的详细分析显示了非典型的粒径分布，我们随后确定了气道管理期间可能产生的非呼吸气溶胶的多个来源，并且可以被视为人为因素。 这些发现表明，声门上气道插入/移除产生的生物气溶胶并不比呼吸多，而且远少于咳嗽。这将为护理声门上气道患者的麻醉师和手术室工作人员设计感染预防策略提供参考。