一个bstract
经皮胸腔程序不应被视为气溶胶产生。这项研究应告知未来关于执行这些程序时适当使用PPE的准则的迭代。https://bit.ly/3xFF71d
致编辑:
严重急性呼吸道综合征2(SARS-COV-2)的医院医院扩散已关注医疗保健中气溶胶生成程序(AGP)的风险[1]。SARS-COV-2已从胸膜液中分离出来,如果在手术过程中对病毒性液体燃烧,则有可能感染人员或患者[[2,,,,3]。但是,从胸膜程序中产生气溶胶的证据非常有限。执行胸腔程序时适当使用个人防护设备(PPE)的当前指南是基于专家意见和预防原则的应用[4]。我们着手量化与在呼吸和咳嗽的正常呼吸活性过程中相比,与在正常呼吸活性过程中采样相比,胸膜过程是否产生明显的气溶胶(具有携带病毒的雾化液体颗粒)。
这项研究是作为曝气研究的一部分进行的,该研究评估了SARS-COV-2在医疗保健中的雾化风险。西北研究伦理委员会授予道德批准(参考:20/NW/0393)。
一个erosol number concentrations were recorded simultaneously using two devices: an optical particle sizer (TSI Inc. model 3330, USA; sampling flow rate 1 L·min-1,,,,samples 0.3–10 µm diameter particles with a sampling period set as 1 s) and an aerodynamic particle sizer (TSI Inc. model 3330, USA; sampling flow rate 1 L·min-1,鞘流4 l·最小-1,样品直径为0.5–20 µm的采样周期为1 s)(图1A). Technical specifications are detailed in a previous publication, with aerosol sampled through a funnel 10 cm from the operating site [5]。Particle losses through impaction in this funnel and tubing setup has been shown in previous work to have minimal effect on the aerosol sampling efficiency [6]。一个erosol generated by an AGP can be measured close to a source or at a remote distance. We measured as close to the source as pragmatically possible to ensure accurate quantification of aerosol concentrations generated by the procedure [7]。
To reduce the background aerosol concentration all procedures were performed in an ultra-clean laminar flow operating theatre (EXFLOW 32; Howarth Air Technology, UK) with high efficiency particulate air filtration and air supply rate of 1200 m3·s-1(每小时550–650空气变化)。在这种环境中,背景气溶胶浓度为0 cm-3,,,,allowing clear attribution of detected aerosol to specific manoeuvres. The air flow is 0.2 m·s-1at 1 m above the floor below the laminar flow. To demonstrate that this airflow does not affect the sampling efficiency of aerosol generated under the laminar flow, the aerosol generated by voluntary coughing and breathing was sampled in the same position, 10 cm from a subject's face. Both the peak aerosol concentration and the mean aerosol concentration produced during the pleural procedure were compared to aerosol produced when the patient coughed or spoke, respectively.
Given the different pleural procedures have common themes, the procedures were sub-classified into five different elements and the aerosol generated by each assessed. All procedures were performed with the patient sitting up, apart from thoracoscopy, which was performed in the lateral position.
Pleural anaesthesia; when local anaesthetic was distilled subcutaneously and down to the pleura, including the aspiration of a small amount of pleural fluid, equivalent to a diagnostic “pleural tap”.
Therapeutic thoracentesis; where a larger volume of fluid is aspirated from the pleural space (equivalent to a therapeutic aspiration).
胸部drain insertion; including indwelling pleural catheter (IPC) and surgical chest drain insertion.
开放胸腔空间程序;在胸腔镜检查期间原位allowing the movement of air between the pleural space and the atmosphere.
胸腔排水管清除。
We also measured any aerosol produced from fluid management systems of:
Underwater seal chest drain bottle (Rocket Medical)
IPC bottle aspiration (BD)
Thopaz+数字胸排排水系统(MEDELA)
10 patients (who were SARS-CoV-2 PCR negative) requiring pleural procedures (three medical thoracoscopies, three IPC insertions (15.5 Fr), one therapeutic aspiration (6 Fr), three IPC removals)) were recruited to the study, with two further patients with chest tubes already原位for pneumothorax with ongoing air leak. The majority of patients were male (10/12) with a median age of 76 (interquartile range 72–79) years.
图1B(logarithmicy-axis) shows the peak aerosol number concentration sampled during each procedure compared to peak number concentrations from coughing and mean number concentrations from breathing. For most procedures, the peak number concentration was of similar magnitude to or less than the mean aerosol number concentration measured during breathing from the same patients or from healthy volunteers from a previous study, and was significantly less than the peak number concentration detected from a cough [5]。The mean concentration for all procedures is typically much less (up to two orders of magnitude) smaller than the mean concentration sampled when a subject is breathing. Again, it should be stressed that breathing is a sustained activity while coughs and these clinical interventions lead to transient events.
图1C与接受医疗胸腔镜检查的患者呼吸或咳嗽相比,单个手术过程中采样的颗粒数浓度之间的差异。
这项研究表明,胸膜的经皮仪器不会导致大量的气溶胶产生。这些过程中的气溶胶总产生显着低于呼吸或咳嗽产生的数量浓度。
当前英国胸recomm社会准则end that “closed pleural procedures such as pleural aspirations and chest drain insertion can be undertaken in level 1 PPE (surgical mask and visor, as well as gown and gloves)” whereas “open procedures such as thoracoscopy and IPC insertion, where pleural fluid may splash, should still be considered AGP [4]。Therefore, level 2 PPE should be worn (FFP3 mask, long sleeved gown, gloves, eye protection)”. On the basis of this evidence, pleural procedures are not aerosol generating and additional PPE (above that indicated for routine patient care) is not required, although eye protection should be worn given the risk of splash.
众所周知,胸膜手术,尤其是那些产生负面胸腔压力的程序(e.g.therapeutic thoracentesis) can induce a cough in participants. We would therefore recommend the patient be asked to wear a surgical facemask, which has been shown to significantly reduce aerosol produced during cough [5]。
Pleural fluid management systems such as underwater seal chest tube bottles have also been seen as a source of aerosol generation, with several studies advocating the use of antiviral filters. Duffy等。[[8]通过水下密封瓶以不同的速度冒泡空气来评估气溶胶的生成,在〜4100 ft的气泡过程中,对最大的气溶胶浓度(与此处研究的尺寸相同的尺寸范围内,在相同的尺寸范围内,0.3-10 µm)。-3,由水的雾化引起。这相当于峰值浓度约为0.14 cm-3,这是类似于峰值浓度we observed during the fluctuations of sampled aerosol number concentration during pleural procedures. We show that the peak number concentration sampled during the pleural procedures was similar to that sampled during the background measurement, orders of magnitude smaller than that sampled during a cough and was never greater than the mean number concentration sampled during a period of quiet breathing. However, given our sample size for underwater seal bottles is small (n=3) and the mitigating factors are simple, we feel guidance should still encourage the use of viral filters or Thopaz devices until further evidence is gathered, especially in pneumothoraces with high air leaks.
In summary, using two methodologies to measure aerosol emission with no background aerosol interference, this study has shown that percutaneous pleural procedures are non-aerosol generating. We hope this will inform future iterations of guidelines on the appropriate use of PPE when performing these procedures.
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supplementary Material
This one-page PDF can be shared freely online.
可共享的PDFERJ-01064-2021.Shareable
一个cknowledgements
We would like to thank all the patients and volunteers who took part in the AERATOR study.
Footnotes
一个ERATOR group (in alphabetical order): The AERATOR group consists of (in alphabetical order): David T. Arnold, Jules Brown, Bryan R. Bzdek, Andrew Davidson, James W. Dodd, Mark Gormley, Florence K.A. Gregson, Fergus W. Hamilton; Nick A. Maskell, James Murray, Johannes Keller, Anthony E. Pickering, Jonathan P. Reid, Sadiyah Sheikh and Andrew Shrimpton.
一个uthor contributions: D.T. Arnold, F.W. Hamilton and N.A. Maskell developed the study idea. F.K.A. Gregson, F.W. Hamilton, J.W. Dodd, B.R. Bzdek and J.P. Reid developed the sampling design. D.T. Arnold, S. Sheikh, F.W. Hamilton, H. Welch, A. Dipper, G.W. Nava and N.A. Maskell collected the primary aerosol data. F.K.A. Gregson, S. Sheikh, B.R. Bzdek and J.P. Reid analysed the aerosol data. All authors were involved in the writing of the manuscript.
Conflict of interest: D.T. Arnold has nothing to disclose.
Conflict of interest: F.K.A. Gregson has nothing to disclose.
利益冲突:S。Sheikh无需透露。
Conflict of interest: F.W. Hamilton has nothing to disclose.
Conflict of interest: H. Welch has nothing to disclose.
利益冲突:A。北斗七星无需透露。
Conflict of interest: G.W. Nava has nothing to disclose.
利益冲突:J.W。多德没有什么可披露的。
利益冲突:A.O。克莱夫没有什么可披露的。
Conflict of interest: B.R. Bzdek has nothing to disclose.
Conflict of interest: J.P. Reid has nothing to disclose.
Conflict of interest: N.A. Maskell has nothing to disclose.
support statement: The AERATOR study was funded by an NIHR/UKRI COVID-19 Rapid Rolling Call (grant number COV0333). D.T. Arnold is funded by an NIHR Doctoral Research Fellowship. F.W. Hamilton is funded by a GW4 Wellcome Trust Fellowship. B.R. Bzdek acknowledges support from the Natural Environment Research Council (NE/P018459/1). Funding information for this article has been deposited with theCrossref Funder Registry。
- received一个pril 12, 2021.
- 公认june 14, 2021.
- Copyright ©The authors 2021.
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