Nash M S, Bilsker M S, Kearney H M, Ramirez J N, Applegate B, Green B A
Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Coral Gables, Florida 33146, USA.
Paraplegia. 1995 Feb;33(2):80-9. doi: 10.1038/sc.1995.20.
The purposes of the study were (1) to characterize left ventricular wall motion, and the cardiodynamic and metabolic responses during electrical stimulation cycle ergometry (ESCE) exercise in tetraplegic people; (2) to test whether these responses linger into the post-exercise recovery period; and (3) to test whether they differ from those imposed by lower extremity continuous passive motion (CPM). Subjects were six tetraplegic males aged 25.8 +/- 3.1 (mean +/- SD) years with spinal cord injuries of 6.7 +/- 3.5 years' duration at the C5 and C6 levels (Frankel classifications A and B). On randomized non-consecutive days, subjects underwent either 30 min of steady-state exercise using transcutaneous electrically-stimulated contractions of bilateral quadriceps, hamstring, and gluteus muscle groups, or 30 min of continuous passive motion at 50 rpm. Data were taken at rest, min 15 and 30 of treatment, and min 5, 15, and 30 post-treatment. Stroke volume (SV) was measured echocardiographically as the product of the left ventricular outflow tract area and the integrated area under the left ventricular outflow tract flow-velocity curve acquired by doppler ultrasound. This value was multiplied by heart rate (HR) to determine the cardiac output (CO). Oxygen consumption (VO2) was monitored spirometrically, with arteriovenous oxygen difference (a-vO2DIFF) computed algebraically. Data were analyzed using repeated measures within-subjects design anaysis of variance, with significance accepted at the 0.05 level. Results showed five subjects had small hyperkinetic ventricles at rest that became more dynamic during ESCE than CPM. Though no systolic dysfunction was noted, all but one subject exhibited some degree of septal hypokinesis at rest and during exercise, possibly indicative of left ventricular noncompliance. Significant effects of condition (ESCE vs CPM), trial (measurement time point), and their interaction, were observed for CO (P < 0.05, 0.01, and 0.0001, respectively), HR (P < 0.0001, 0.05 and 0.005, respectively), and VO2 (P < 0.001, 0.05 and 0.005, respectively). A significant trial and condition by trial interaction was found for a-vO2DIFF (P < 0.05 and 0.0001, respectively). No effects for condition, trial or their interaction were found for SV or BPDIAS. Electrical stimulation cycle ergometry-treated subjects achieved peak VO2 of 712 +/- 300 ml min-1, 2.63 times baseline, with 56% elevation of a-vO2DIFF. Cardiac output increased from 3.5 +/- 1.51 min-1 to 6.0 +/- 2.11 min-1, an elevation solely attributable to a 57% increase in HR. Thus, both CO and a-vO2DIFF accounted for elevated VO2 during ESCE.(ABSTRACT TRUNCATED AT 400 WORDS)
（1）描述四肢瘫痪患者在电刺激周期运动试验（ESCE）期间的左心室壁运动、心脏动力学和代谢反应；（2）测试这些反应是否会持续到运动后的恢复期；（3）测试它们是否与下肢持续被动运动（CPM）引起的反应不同。受试者为6名男性四肢瘫痪患者，年龄25.8±3.1（平均±标准差）岁，脊髓损伤6.7±3.5年，损伤平面在C5和C6水平（Frankel分级为A和B）。在随机的非连续日期，受试者接受30分钟的稳态运动，通过经皮电刺激双侧股四头肌、腘绳肌和臀肌群收缩，或在50转/分钟的速度下进行30分钟的持续被动运动。在静息状态、治疗的第15分钟和第30分钟以及治疗后第5分钟、第15分钟和第30分钟采集数据。通过超声心动图测量每搏输出量（SV），其为左心室流出道面积与通过多普勒超声获得的左心室流出道流速曲线下的积分面积的乘积。该值乘以心率（HR）以确定心输出量（CO）。通过肺量计监测耗氧量（VO2），通过代数计算动静脉氧分压差（a-vO2DIFF）。使用重复测量的受试者内设计方差分析对数据进行分析，显著性水平设定为0.05。结果显示，5名受试者在静息时左心室运动亢进程度较小，在ESCE期间比CPM时更具活力。虽然未观察到收缩功能障碍，但除一名受试者外，所有受试者在静息和运动期间均表现出一定程度的室间隔运动减弱，这可能表明左心室顺应性降低。在CO（分别为P<0.05、0.01和0.0001）、HR（分别为P<0.0001、0.05和0.005）和VO2（分别为P<0.001、0.05和0.005）方面，观察到运动状态（ESCE与CPM）、试验（测量时间点）及其相互作用的显著影响。在a-vO2DIFF方面发现了显著的试验以及试验与运动状态的相互作用（分别为P<0.05和0.0001）。在SV或BPDIAS方面未发现运动状态、试验或其相互作用的影响。接受电刺激周期运动试验治疗的受试者VO2峰值达到712±300毫升/分钟，是基线的2.63倍，a-vO2DIFF升高56%。心输出量从3.5±1.5升/分钟增加到6.0±2.1升/分钟，升高完全归因于HR增加57%。因此，在ESCE期间，CO和a-vO2DIFF均导致VO2升高。（摘要截断于400字）
