低钾型周期性瘫痪患者运动诱发试验中肌力和肌电图改变与血钾的关系  

Correlation between muscle strength and electromyography with blood potassium level after exercise test in patients with hypokalemic periodic paralysis

作　　者：刘明生[1] 崔丽英[1] 冯新红[1] 管宇宙[1] 

机构地区：[1]中国医学科学院北京协和医院神经内科,100730

出　　处：《中华神经科杂志》2011年第11期732-734,共3页Chinese Journal of Neurology

摘　　要：目的通过长时运动诱发试验，观察低钾型周期性瘫痪患者肌力和肌电图的变化与血钾之间的关系。方法收集确诊为低钾型周期性瘫痪患者78例，对小指展肌进行运动诱发试验测定，以拇短展肌作为对照，观察120min，测定运动诱发前后尺神经／小指展肌和正中神经／拇短展肌复合肌肉动作电位（compound muscle action potential，CMAP）波幅变化，同时观察患者小指外展和小指内收肌力以及拇短展肌肌力的变化，部分患者测定运动前后血钾水平。分析运动后不同肌肉的肌力、CMAP波幅与血钾之间的关系。结果在小指外展运动后，78例患者尺神经CMAP波幅运动后比运动前明显下降，分别为（4．6±2．7）、（9．6±3．2）mV（t=16．047，P=0．000），而正中神经CMAP波幅在小指外展运动后与运动前相比无明显差异，分别为（10．9±4．2）、（11．2±3．9）mV（t=0．673，P=0．822）。在运动后，76例小指外展肌力下降；有41例小指外展肌力小于Ⅲ级，但同侧小指内收和拇短展肌肌力仍为V级，对其中10例患者在运动前和运动后测定血钾，结果无明显差异，分别为（3．8±0．3）、（3．9±0．4）mmol／L（t=0．395，P=0．702）。结论在低钾型周期性瘫痪患者进行运动诱发试验时，血钾并非影响肌力和CMAP波幅变化的关键因素。Objective To assess the correlations between muscle strength and amplitude of compound muscle action potential （CMAP） with blood potassium level in hypokalemic periodic paralysis after long exercise test （ET）. Methods ET of abductor digiti minimi （ADM） was performed on 78 patients with hypokalemic periodic paralysis. Ulnar and median CMAP amplitude, blood potassium level, muscle strength of ADM, palmar interossei muscle and abductor pollicis brevis were measured before and 120 minutes after exercise. The correlations of muscle strength, CMAP amplitude and blood potassium level were analyzed. Results Ulnar CMAP amplitude was （4.6 ± 2. 7 ） mV after ET and （9.6 ± 3.2） mV before ET （t = 16. 047, P = 0. 000 ） in 78 patients with hypokalemie periodic paralysis, respectively. Median CMAP amplitude was（ 10. 9 ±4. 2）mV after ET and （ 11.2 ±3.9） mV before ET （ t =0. 673, P =0. 822） , respectively. After ET, muscle strength of ADM decreased in 76 patients, score on MRC was less than Ⅲ in ADM but V in palmar interossei muscle and abductor pollicis brevis in 41 patients, the blood potassium level was tested in 10 of them, which was （3.8 ± 0. 3 ） mmol/L before ET and （3.9 ± 0. 4 ） mmol/L after ET（ t = 0. 395, P = 0. 702）. Conclusion In patients with hypokalemic periodic paralysis, blood potassium level is not the key factor affecting muscle strength and CMAP amplitude after ET.

关 键 词：低钾性周期性麻痹 运动试验 动作电位 肌电描记术 钾 

分 类 号：R746[医药卫生—神经病学与精神病学]