特发性肌萎缩侧索硬化症患者的肺功能检查和膈神经复合肌肉动作电位。

Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore, India.

Acta Neurol Scand. 2010 Jun;121(6):400-5. doi: 10.1111/j.1600-0404.2009.01199.x. Epub 2010 Jan 12.

BACKGROUND

Respiratory failure is the primary cause of death in patients with amyotrophic lateral sclerosis (ALS). Diaphragmatic compound muscle action potentials (DCMAP) are valid parameters to assess the respiratory muscle innervation.

AIM

In this study we propose to establish evidence of pulmonary dysfunction in patients with ALS and its relation to DCMAP parameters among patients with sporadic ALS.

MATERIALS AND METHODS

Twenty nine patients (M-20, F-9) diagnosed to have sporadic ALS by El. Escorial criteria, without symptoms of pulmonary dysfunction, and able to perform the PFT satisfactorily, were studied. Thirty controls (M-20, F-10) were selected from patient's relatives. Forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)), peak expiratory flow rate (PEFR) and maximum voluntary ventilation (MVV) were measured by spirometry. Maximum expiratory pressure (MEP) was measured by digital peak pressure monitor. Right phrenic nerve conductions (DCMAP) were performed and the latencies and amplitude of diaphragmatic com-pound action potential (DCMAP) was recorded in controls and ALS patients.

RESULTS

The mean age of patients was 51.41 +/- 10.72 years (37-82) and control was 53.57 +/- 8.85 years (30-68). None of the patients had symptoms or clinical evidence of respiratory dysfunction. The FVC, FEV1, PEFR, MVV, MIP and MEP were significantly (P < 0.001) reduced in ALS. The mean DCMAP amplitude was reduced among patients (610 +/- 506.231 muv) as compared to controls (1303.33 +/- 584.56, P < 0.001) and mean latency was increased in patients (9.73 +/- 2.57 ms) compared to controls (7.69 +/- 0.87, P = 0.001). There was significant negative correlation between PFTs and latencies of DCMAP. Amplitude of DCMAP did not correlate with PFTs.

CONCLUSION

There is significant negative correlation between DCMAP latencies and PFTs suggesting early loss of myelinated fibres and diaphragmatic dysfunction. DCMAP latencies may be a good indicator of early respiratory muscle involvement and also of disease progression in ALS.

背景

呼吸衰竭是肌萎缩侧索硬化症（ALS）患者死亡的主要原因。膈肌复合肌肉动作电位（DCMAP）是评估呼吸肌神经支配的有效参数。

目的

本研究旨在确定 ALS 患者的肺功能障碍，并探讨其与散发型 ALS 患者 DCMAP 参数的关系。

材料和方法

共纳入 29 例（男 20 例，女 9 例）符合 El Escorial 标准诊断的散发型 ALS 患者，这些患者无肺功能障碍症状，且能满意完成 PFT 检查。同时选择 30 例患者的亲属作为对照组（男 20 例，女 10 例）。通过肺活量计测量用力肺活量（FVC）、第 1 秒用力呼气量（FEV1）、呼气峰流速（PEFR）和最大自主通气量（MVV）。通过数字峰压监测仪测量最大呼气压力（MEP）。对右膈神经进行传导检测，并记录对照组和 ALS 患者的膈神经复合动作电位（DCMAP）的潜伏期和振幅。

结果

患者的平均年龄为 51.41±10.72 岁（37-82 岁），对照组为 53.57±8.85 岁（30-68 岁）。所有患者均无呼吸功能障碍的症状或临床证据。ALS 患者的 FVC、FEV1、PEFR、MVV、MIP 和 MEP 均显著降低（P＜0.001）。与对照组（1303.33±584.56μV）相比，患者的平均 DCMAP 振幅降低（610±506.231μV，P＜0.001），潜伏期延长（9.73±2.57ms），与对照组（7.69±0.87ms，P=0.001）相比差异有统计学意义。DCMAP 潜伏期与 PFTs 之间呈显著负相关。DCMAP 振幅与 PFTs 无相关性。