Engeroff Tobias, Groneberg David A, Niederer Daniel
Division Health and Performance, Institute of Occupational, Social and Environmental Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, Building 9B, 60590, Frankfurt am Main, Germany.
Institute of Occupational, Social and Environmental Medicine, Goethe-University Frankfurt, Frankfurt am Main, Germany.
Sports Med Open. 2021 Dec 11;7(1):92. doi: 10.1186/s40798-021-00388-6.
Protection against airborne infection is currently, due to the COVID-19-associated restrictions, ubiquitously applied during public transport use, work and leisure time. Increased carbon dioxide re-inhalation and breathing resistance may result thereof and, in turn, may negatively impact metabolism and performance.
To deduce the impact of the surgical mask and filtering face piece type 2 (FFP2) or N95 respirator application on gas exchange (pulse-derived oxygen saturation (SpO), carbon dioxide partial pressure (PCO), carbon dioxide exhalation (VCO) and oxygen uptake (VO)), pulmonary function (respiratory rate and ventilation) and physical performance (heart rate HR, peak power output W).
Systematic review with meta-analysis. Literature available in Medline/Pubmed, the Cochrane Library and the Web of Knowledge with the last search on the 6 of May 2021. Eligibility criteria: Randomised controlled parallel group or crossover trials (RCT), full-text availability, comparison of the acute effects of ≥ 1 intervention (surgical mask or FFP2/N95 application) to a control/comparator condition (i.e. no mask wearing). Participants were required to be healthy humans and > 16 years of age without conditions or illnesses influencing pulmonary function or metabolism. Risk of bias was rated using the crossover extension of the Cochrane risk of bias assessment tool II. Standardised mean differences (SMD, Hedges' g) with 95% confidence intervals (CI) were calculated, overall and for subgroups based on mask and exercise type, as pooled effect size estimators in our random-effects meta-analysis.
Of the 1499 records retrieved, 14 RCTs (all crossover trials, high risk of bias) with 25 independent intervention arms (effect sizes per outcome) on 246 participants were included. Masks led to a decrease in SpO during vigorous intensity exercise (6 effect sizes; SMD = - 0.40 [95% CI: - 0.70, - 0.09], mostly attributed to FFP2/N95) and to a SpO-increase during rest (5 effect sizes; SMD = 0.34 [95% CI: 0.04, 0.64]); no general effect of mask wearing on SpO occurred (21 effect sizes, SMD = 0.34 [95% CI: 0.04, 0.64]). Wearing a mask led to a general oxygen uptake decrease (5 effect sizes, SMD = - 0.44 [95% CI: - 0.75, - 0.14]), to slower respiratory rates (15 effect sizes, SMD = - 0.25 [95% CI: - 0.44, - 0.06]) and to a decreased ventilation (11 effect sizes, SMD = - 0.43 [95% CI: - 0.74, - 0.12]). Heart rate (25 effect sizes; SMD = 0.05 [95% CI: - 0.09, 0.19]), W (9 effect sizes; SMD = - 0.12 [95% CI: - 0.39, 0.15]), PCO (11 effect sizes; SMD = 0.07 [95% CI: - 0.14, 0.29]) and VCO (4 effect sizes, SMD = - 0.30 [95% CI: - 0.71, 0.10]) were not different to the control, either in total or dependent on mask type or physical activity status.
The number of crossover-RCT studies was low and the designs displayed a high risk of bias. The within-mask- and -intensity-homogeneous effects on gas exchange kinetics indicated larger detrimental effects during exhausting physical activities. Pulse-derived oxygen saturation was increased during rest when a mask was applied, whereas wearing a mask during exhausting exercise led to decreased oxygen saturation. Breathing frequency and ventilation adaptations were not related to exercise intensity. FFP2/N95 and, to a lesser extent, surgical mask application negatively impacted the capacity for gas exchange and pulmonary function but not the peak physical performance. Registration: Prospero registration number: CRD42021244634.
由于与新冠疫情相关的限制措施，目前在乘坐公共交通工具、工作和休闲期间，人们普遍采取防护措施以防止空气传播感染。由此可能导致二氧化碳再吸入增加和呼吸阻力增大，进而可能对新陈代谢和身体机能产生负面影响。
推断佩戴外科口罩、2型过滤面罩（FFP2）或N95口罩对气体交换（脉搏血氧饱和度（SpO）、二氧化碳分压（PCO）、二氧化碳呼出量（VCO）和氧气摄入量（VO））、肺功能（呼吸频率和通气量）以及身体机能（心率HR、峰值功率输出W）的影响。
系统评价与荟萃分析。检索了Medline/Pubmed、Cochrane图书馆和Web of Knowledge中截至2021年5月6日的文献。纳入标准：随机对照平行组或交叉试验（RCT）、全文可获取、≥1种干预措施（佩戴外科口罩或FFP2/N95口罩）与对照/比较条件（即不戴口罩）的急性效应比较。参与者须为健康人群，年龄>16岁，且无影响肺功能或新陈代谢的疾病或状况。使用Cochrane偏倚风险评估工具II的交叉扩展版对偏倚风险进行评级。在我们的随机效应荟萃分析中，计算了总体及基于口罩和运动类型的亚组的标准化平均差（SMD，Hedges' g）及其95%置信区间（CI），作为合并效应量估计值。
在检索到的1499条记录中，纳入了14项RCT（均为交叉试验，偏倚风险高），涉及246名参与者的25个独立干预组（每个结局的效应量）。口罩导致剧烈运动时SpO降低（6个效应量；SMD = -0.40 [95% CI：-0.70，-0.09]，主要归因于FFP2/N95口罩），休息时SpO升高（5个效应量；SMD = 0.34 [95% CI：0.04，0.64]）；佩戴口罩对SpO无总体影响（21个效应量，SMD = 0.34 [95% CI：0.04，0.64]）。佩戴口罩导致总体氧气摄入量降低（5个效应量，SMD = -0.44 [95% CI：-0.75，-0.14]）、呼吸频率减慢（15个效应量，SMD = -0.25 [95% CI：-0.44，-0.06]）和通气量降低（11个效应量，SMD = -0.43 [9�% CI：-0.74，-0.12]）。心率（25个效应量；SMD = 0.05 [95% CI：-0.09，0.19]）、W（9个效应量；SMD = -0.12 [95% CI：-0.39，0.15]）、PCO（11个效应量；SMD = 0.07 [95% CI：-0.14，0.29]）和VCO（4个效应量，SMD = -0.30 [95% CI：-0.71，0.10]）与对照组相比，总体上或取决于口罩类型或身体活动状态均无差异。
交叉RCT研究数量较少，且设计显示出较高的偏倚风险。口罩和强度均一的情况下对气体交换动力学的影响表明，在剧烈体力活动期间有害影响更大。佩戴口罩时休息期间脉搏血氧饱和度升高，而在剧烈运动时佩戴口罩会导致血氧饱和度降低。呼吸频率和通气量的适应性变化与运动强度无关。FFP2/N95口罩以及在较小程度上外科口罩会对气体交换能力和肺功能产生负面影响，但对身体机能峰值无影响。注册信息：Prospero注册号：CRD42021244634。
