Influence of ventilator settings in determining respiratory frequency during mechanical ventilation.
Influence of ventilator settings in determining respiratory frequency during mechanical ventilation.
复制标题
呼吸机设置对确定机械通气期间呼吸频率的影响。
DOI：
10.1164/ajrccm.160.5.9810086
复制
发表时间：
1999
影响因子：
24.7
通讯作者：
M. Tobin
中科院分区：
文献类型：
--
作者：
F. Laghi;K. Karamchandani;M. Tobin
在机械通气过程中，吸气流量和潮气量（VT）的变化已被证明会改变呼吸频率（f）。然而，流量和VT的变化伴随着呼吸机吸气时间（TI，（vent））的改变，目前尚不清楚哪个变量是主要决定因素。为了解决这个问题，我们在15名接受辅助控制通气的健康志愿者中采用了四种方案。当VT固定且以30、60和90 L/min输送流量时，f随流量增加和TI（通气）降低而增加。当流量保持恒定，VT在0.5、1.0和1.5 L之间变化时，f随VT和TI（通气）降低而增加。当流量从60 L/min增加到90 L/min时，这些变化与VT设置1.0和1.5 L平衡，以保持恒定的TI（通气），f不变。当流量和VT保持恒定，通过应用吸气暂停（0 - 2 s）改变TI（vent）时，f作为TI（vent）增加的函数而降低（p < 0.001）。总之，机械通气期间施加的呼吸机吸气时间可以独立于输送的吸气流量和VT确定f。
During mechanical ventilation, changes in inspiratory flow and tidal volume (VT) have been shown to alter respiratory frequency (f ). However, the changes in flow and VT have been accompanied by alteration in ventilator inspiratory time (TI,(vent)), and it is not clear which variable is the primary determinant. To address this issue, we employed four protocols in 15 healthy volunteers receiving assist-control ventilation. When VT was fixed and flow was delivered at 30, 60, and 90 L/min, f increased as a function of the increase in flow and the decrease in TI,(vent). When flow was held constant and VT was changed among 0.5, 1.0, and 1.5 L, f increased as a function of the decreases in VT and TI,(vent). When flow was increased from 60 to 90 L/min and these changes were balanced with VT settings of 1.0 and 1.5 L to maintain a constant TI,(vent), f did not change. When flow and VT were held constant and TI,(vent) was varied by the application of inspiratory pauses (0 to 2 s), f decreased as a function of the increase in TI,(vent) (p < 0.001). In conclusion, the imposed ventilator inspiratory time during mechanical ventilation can determine f independently of delivered inspiratory flow and VT.