Daubenspeck J A, Leiter J C, McGovern J F, Knuth S L, Kobylarz E J
Department of Physiology, Dartmouth Medical School, Hanover, New Hampshire 03756.
J Appl Physiol (1985). 1989 Oct;67(4):1525-34. doi: 10.1152/jappl.1989.67.4.1525.
We have developed a new technique for diaphragmatic electromyography using an array of seven sequential electrode pairs at 1.0-cm spacing on an esophageal catheter. This array provides information about the spatial distribution of the electrical field generated by the diaphragm and reveals a sharply peaked variation of electrical potential with distance along the esophagus. The rectified and integrated information from each of the seven pairs is summed to give an approximation to the total electrical activity over the span of the array, providing a signal that is relatively insensitive to the position of the array over approximately 4 cm of catheter movement and removes the requirement for balloon stabilization of the catheter. With our array, we have confirmed the artifact in the evoked compound muscle action potential that seems to be related to diaphragmatic shape as reported by others who used supramaximal phrenic nerve stimulation, but the magnitude of this artifact (compared with the functional residual capacity level) was modest near functional residual capacity, averaging 12 +/- 14% (SD) for lung volumes 1.0 l above and -4 +/- 15% for lung volumes 1.0 l below functional residual capacity along the rib cage-abdomen relaxation line.
我们开发了一种用于膈肌肌电图检查的新技术，该技术使用一根食管导管上间距为1.0厘米的七个连续电极对组成的阵列。这个阵列提供了有关膈肌产生的电场空间分布的信息，并揭示了沿食管方向电位随距离的急剧峰值变化。对七个电极对中每一个的整流和积分信息进行求和，以近似得出阵列范围内的总电活动，从而提供一个信号，该信号在导管移动约4厘米的范围内对阵列位置相对不敏感，并且消除了对导管气囊稳定的需求。使用我们的阵列，我们证实了诱发复合肌肉动作电位中的伪影，这似乎与其他使用超强膈神经刺激的人所报告的膈肌形状有关，但在功能残气量附近，该伪影的幅度（与功能残气量水平相比）较小，沿胸廓 - 腹部松弛线，高于功能残气量1.0升的肺容积时平均为12 +/- 14%（标准差），低于功能残气量1.0升的肺容积时为 -4 +/- 15%。
