High and low frequency transcutaneous electrical nerve stimulation in post-cesarean pain intensity

The current study aim was evaluate the analgesic effect of TENS modulation for high (100 Hz) and low (4 Hz) frequency in post-cesarean pain. 34 postpartum women were randomly divided into three treatment groups: 100 Hz (G100), 4 Hz (G4) and Placebo (GP) (appliance off). Pain intensity was assessed by the NRS (Numeric Rating Scale) before, immediately after application of TENS, and every 20 minutes until an hour after the eletroanalgesia session. We used the Friedman test and Mann-Whitney U test (p<0.05) for statistical analysis. The results showed significant reduction of NRS in G100 only relative to pretreatment condition (p<0.05). At intervals after treatment, the G100 had a significant reduction of pain during all intervals (p<0.05). The G4 has significantly decreased only in intervals of 40' and 60', and the GP, only in the range of 60' (p<0.05). Modulation of TENS for high pulse rate showed greater analgesic effect than the low frequency TENS in post-cesarean mothers.

本研究旨在评估经皮神经电刺激（Transcutaneous Electrical Nerve Stimulation, TENS）的100Hz高频与4Hz低频模式对剖宫产术后疼痛的镇痛效果。研究共纳入34名产后女性，按随机原则分为三组：100Hz组（G100）、4Hz组（G4）及安慰剂组（GP，设备处于关闭状态）。分别于经皮神经电刺激治疗前、治疗即刻及电镇痛疗程结束后每20分钟（持续观测1小时），采用数字评定量表（Numeric Rating Scale, NRS）评估疼痛强度。本研究采用弗里德曼检验与曼-惠特尼U检验进行统计分析，检验显著性水准设定为p<0.05。结果显示，仅100Hz组的疼痛评分较治疗前出现显著降低（p<0.05）。治疗后各时间区间内，100Hz组的疼痛程度在所有观测节点均呈现显著下降（p<0.05）；4Hz组仅在术后40分钟与60分钟时间点出现疼痛评分显著降低，而安慰剂组仅在60分钟时间点出现评分下降（p<0.05）。研究结果表明，高频脉冲参数的经皮神经电刺激对剖宫产术后产妇的镇痛效果优于低频模式。