Department of Anesthesiology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, People's Republic of China.
Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
Physiol Meas. 2022 Jun 28;43(6). doi: 10.1088/1361-6579/ac70a3.
Mask positive-pressure ventilation could lead to lung ventilation inhomogeneity, potentially inducing lung function impairments, when compared with spontaneous breathing. Lung ventilation inhomogeneity can be monitored by chest electrical impedance tomography (EIT), which could increase our understanding of mask ventilation-derived respiratory mechanics. We hypothesized that the two-handed mask holding ventilation technique resulted in better lung ventilation, reflected by respiratory mechanics, when compared with the one-handed mask holding technique.Elective surgical patients with healthy lungs were randomly assigned to receive either one-handed mask holding (one-handed group) or two-handed mask holding (two-handed group) ventilation. Mask ventilation was performed by certified registered anesthesiologists, during which the patients were mechanically ventilated using the pressure-controlled mode. EIT was used to assess respiratory mechanics, including ventilation distribution, global and regional respiratory system compliance (), expiratory tidal volume (TVe) and minute ventilation volume. Hemodynamic parameters and the PaO-FiOratio were also recorded.Eighty adult patients were included in this study. Compared with spontaneous ventilation, mask positive-pressure ventilation caused lung ventilation inhomogeneity with both one-handed(global inhomogeneity index: 0.40 ± 0.07 versus 0.50 ± 0.15; < 0.001) and two-handed mask holding (0.40 ± 0.08 versus 0.50 ± 0.13; < 0.001). There were no differences in the global inhomogeneity index ( = 0.948) between the one-handed and two-handed mask holding. Compared with the one-handed mask holding, the two-handed mask holding was associated with higher TVe (552.6 ± 184.2 ml versus 672.9 ± 156.6 ml, = 0.002) and higher global(46.5 ± 16.4 ml/cmHO versus 53.5 ± 14.5 ml/cmHO, = 0.049). No difference in PaO-FiOratio was found between both holding techniques ( = 0.743).The two-handed mask holding technique could not improve the inhomogeneity of lung ventilation when monitored by EIT during mask ventilation although it obtained larger expiratory tidal volumes than the one-handed mask holding technique.
面罩正压通气可能会导致肺通气不均匀，从而可能导致肺功能受损，与自主呼吸相比。肺通气不均匀可以通过胸部电阻抗断层成像术 (EIT) 监测，这可以增加我们对面罩通气衍生呼吸力学的理解。我们假设双手面罩保持通气技术与单手面罩保持技术相比，在呼吸力学方面导致更好的肺通气。
选择接受健康肺手术的患者被随机分配接受单手面罩保持 (单手组) 或双手面罩保持 (双手组) 通气。面罩通气由经过认证的注册麻醉师进行，在此期间，患者使用压力控制模式进行机械通气。EIT 用于评估呼吸力学，包括通气分布、整体和区域呼吸系统顺应性 ()、呼气潮气量 (TVe) 和分钟通气量。还记录了血流动力学参数和 PaO-FiOratio。
这项研究共纳入 80 名成年患者。与自主通气相比，面罩正压通气导致单手 (整体不均匀指数：0.40 ± 0.07 与 0.50 ± 0.15；<0.001) 和双手面罩保持 (0.40 ± 0.08 与 0.50 ± 0.13；<0.001) 时的肺通气不均匀。单手和双手面罩保持之间的整体不均匀指数无差异 (=0.948)。与单手面罩保持相比，双手面罩保持与更高的 TVe(552.6 ± 184.2 ml 与 672.9 ± 156.6 ml，=0.002) 和更高的整体 (46.5 ± 16.4 ml/cmHO 与 53.5 ± 14.5 ml/cmHO，=0.049) 相关。两种握持技术之间的 PaO-FiOratio 无差异 (=0.743)。
尽管双手面罩保持技术获得的呼气潮气量大于单手面罩保持技术，但在面罩通气期间通过 EIT 监测时，双手面罩保持技术并不能改善肺通气的不均匀性。
