Yang K L
Division of Pulmonary and Critical Care Medicine, University of Texas Health Science Center, Houston.
Chest. 1992 Dec;102(6):1829-32. doi: 10.1378/chest.102.6.1829.
Although weaning parameters can accurately predict weaning outcome, variability of the measurements of these parameters has not been closely examined. In the current study, we examined the reproducibility of these parameters using a standardized technique. Before the weaning trial, maximal inspiratory pressure (PImax), minute ventilation (VE), respiratory frequency (f), tidal volume (VT), rapid shallow breathing index (f/VT), and vital capacity (VC) were obtained on three trials over a period of 15 min. The results of these parameters over three measurements were compared. There were no statistical differences in the values of PImax, VE, f, VT, and f/VT over three trials (p = 0.45, p = 0.37, p = 0.69, p = 0.64, p = 0.1, respectively). The VC was the only parameter that showed statistical differences among three trials (p < 0.05). For the group, respiratory frequency had the lowest coefficient of variation (COV = SD/mean x 100 percent) at 6.7 percent while the VC had the highest COV at 19.6 percent. We concluded that most weaning parameters of breathing pattern can be measured reliably with bedside instruments using a standard technique.
尽管撤机参数能够准确预测撤机结果，但这些参数测量值的变异性尚未得到深入研究。在本研究中，我们使用标准化技术检测了这些参数的可重复性。在撤机试验前，在15分钟内进行三次测量，获取最大吸气压力（PImax）、分钟通气量（VE）、呼吸频率（f）、潮气量（VT）、快速浅呼吸指数（f/VT）和肺活量（VC）。比较这三项测量中这些参数的结果。三次试验中PImax、VE、f、VT和f/VT的值无统计学差异（分别为p = 0.45、p = 0.37、p = 0.69、p = 0.64、p = 0.1）。肺活量是三项试验中唯一显示出统计学差异的参数（p < 0.05）。对于该组，呼吸频率的变异系数（COV =标准差/平均值×100%）最低，为6.7%，而肺活量的变异系数最高，为19.6%。我们得出结论，使用标准技术通过床边仪器能够可靠地测量大多数呼吸模式的撤机参数。
