经食管电极和表面电极测量膈神经传导时间和膈肌复合肌肉动作电位临床评价

Comparison of measurement of phrenic nerve conduction time and evoked compound muscle action potential of diaphragm with surface electrodes and oesophageal electrodes

目的探讨表面电极测量膈神经传导时间和膈肌动作电位的可行性。方法选择2005年3月至6月广州医学院第一附属医院广州呼吸疾病研究所15名健康志愿者,使用表面电极通过单侧磁刺激膈神经测定膈神经传导时间(PNCT)及诱发的膈肌复合肌肉动作电位(CMAP)的幅值,并与标准的经食管电极测定结果比较。结果(1)经食管电极测定的PNCT与表面电极相似(左侧:t=0·397,P=0·698;右侧:t=1·207,P=0·247);经食管电极测定的CMAP幅值显著高于表面电极(左侧:t=-5·635,P<0·001;右侧:t=-5·881,P<0·001)。(2)经食管电极和表面电极测定的左侧CMAP幅值无显著相关性(r=0·371,P=0·174),右侧有显著相关性(r=0·575,P=0·025)。(3)两种途径测定的双侧PNCT及CMAP幅值与年龄、身高、体重及腹围均无相关性(P均>0·05)。结论采用单侧磁刺激膈神经时,表面电极测得的PNCT与食管电极检测结果相似,但CMAP降低。表面电极作为无创的检测方法,一定程度上可以替代食管电极来评价膈神经和膈肌功能。

Objective To evaluate the feasibility of measuring phrenic nerve conduction time （PNCT） and elicited compound muscle action potential （CMAP） of diaphragm with surface electrodes. Methods PNCT and amplitude of diaphragm CMAP elicited by unilateral magnetic stimulation （UMS） of the phrenic nerve were measured with surface electrodes and the results were compared with those measured with oesophageal electrodes. Results （1） PNCT measured with oesophageal electrode was similar to those measured with surface electrode; the amplitude of CMAP measured with oesophageal electrode was higher than those with surface electrode. （2） There was a significant relationship between the amplitudes of right CMAP measured with oesophageal electrode and those with surface electrodes, whereas there was no such relationship for the left side. （3） The PNCT and the amplitude of CMAP were not related to age, height, weight and perimeter of abdomen no matter measured with oesophageal or surface electrodes. Conclusion Surface electrodes is a useful and noninvasive method to evaluate the function of phrenic nerve and diaphragm.