高频单、双向喷射通气气流速度与CO2排出效应的实验研究

在相同条件下测量与探讨高频单向喷射通气（ＨＦＳＪＶ）和高频双向喷射通气（ＨＦＴＪＶ）时上呼吸道气流的性质、气流速度与ＣＯ＿２排出效应之间的关系。结果：自主呼吸时，吸气气流以层流为主，呼气以湍流为主。ＨＦＳＪＶ和ＨＦＴＪＶ时进出气流均以湍流为主，两者测值比较，ＨＦＴＪＶ出气速度显著增大（Ｐ＜０．０５），ＰａＣＯ＿２显著降低（Ｐ＜０．０５），气道压保持正值无明显变化；ＨＦＴＪＶ时进出气速度随反喷躯动压的增大而增大，ＰａＣＯ＿２与出气速度呈显著负相关（ｒ＝－０．８７，Ｐ＜０．０５）。本实验为ＨＦＳＴＪ和ＨＦＴＪＶ更安全合理地用于临床提供了理论依据。

Experimental studies on Flow Velocity and CO_2 Elimilation Efficiency During HFSJV and HFTJV

The relationship of the characteristics and velocity of air flow in the upper respiratorytract to the CO_2 elimination efficiency during high frequency single-way jet ventilation(HF-SJV)and high frequency two-way jet ventilation(HFTJV)under the same condition was de-termined and discussed, During spontaneous respiration,inspiratory flow was mainly laminarand expiratory flow turbulent,During HFSJV and HFTJV,both flows were turbulent,Theof expiratory flow velocity during HFTJV increased significantly(P<0.05)as compared withthat during HFSJV, PaCO_2 decreased significantly(P< 0.05);the airway pressure main-tained positive value without significant change.During HFTJV,inspiratory or expiratoryflow velocity increased with increase of inverse driving pressure; significant negative correla-tion was found between expiratory flow velocity and PaCO_2(r=-0. 87, P<0. 05),Thisstudy provides a theoratical basis for safe and reasonable use of HFSJV and HFSJV clinical-ly.