Department of Anesthesiology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minamikoshigaya, Koshigaya, Saitama, 343-8555, Japan.
J Anesth. 2023 Oct;37(5):787-793. doi: 10.1007/s00540-023-03237-w. Epub 2023 Aug 4.
It is not clear whether or not high-flow nasal oxygenation used in patients with severe respiratory tract infection, or coughing, increases the risk of infection to the healthcare personnel, and whether or not applying a surgical mask to the patient's face or treating the patient in a negative-pressure room can reduce the risk.
In a randomized crossover design, we compared in 50 participants receiving high-flow nasal oxygenation, the aerosol counts measured at approximately 20 cm above the participant's mouth in 32 different circumstances (with or without coughing, with or without wearing a surgical mask, at four different flow rates of oxygenation, in a positive- or negative-pressure operating room).
In a positive-pressure room, a surgical mask significantly decreased the aerosol counts during coughing (P = 0.0005), or during no coughing (P = 0.009), under high-flow nasal oxygenation (at 60 l.min). In the negative-pressure room, the aerosol count was significantly lower than in the positive-pressure room, for all the circumstances (all P < 0.001), and a surgical mask significantly decreased the aerosol counts during coughing (P = 0.047) but not during no coughing (P = 0.60).
In conclusion, treating a patient in a negative-pressure room, or applying a surgical mask, during high-flow nasal oxygenation (with the flow rate of 60 l.min) would inhibit, but would not completely prevent, dispersion of aerosols by coughing.
目前尚不清楚在严重呼吸道感染或咳嗽的患者中使用高流量鼻氧疗是否会增加医护人员感染的风险，以及在患者面部佩戴外科口罩或在负压病房中治疗患者是否可以降低风险。
采用随机交叉设计，我们在 50 名接受高流量鼻氧疗的参与者中比较了 32 种不同情况下（咳嗽时和不咳嗽时、是否佩戴外科口罩、氧疗时的四种不同流量、正压或负压手术室）在参与者口部上方约 20cm 处测量的气溶胶计数。
在正压手术室中，在高流量鼻氧疗（60l.min）时，外科口罩可显著降低咳嗽时（P=0.0005）或不咳嗽时（P=0.009）的气溶胶计数。在负压手术室中，所有情况下（所有 P<0.001）的气溶胶计数均明显低于正压手术室，外科口罩可显著降低咳嗽时的气溶胶计数（P=0.047），但不降低不咳嗽时的气溶胶计数（P=0.60）。
总之，在进行高流量鼻氧疗（流速为 60l.min）时，在负压病房中治疗患者或佩戴外科口罩可抑制气溶胶的扩散，但不能完全阻止咳嗽时气溶胶的扩散。
