Comparison of continuous and intermittent transcutaneous electrical nerve stimulation in postoperative pain management after coronary artery bypass grafting: a randomized, placebo-controlled prospective study.
ABSTRACT We compared the effectiveness of continuous transcutaneous electrical nerve stimulation (TENS) and intermittent TENS in the management of pain after coronary artery bypass grafting (CABG).
We randomized 100 patients who had undergone median sternotomy for CABG into 4 groups with 25 patients each: (1) continuous TENS (CTENS) and pharmacologic analgesia, (2) intermittent TENS (ITENS) and pharmacologic analgesia, (3) placebo TENS (PTENS) and pharmacologic analgesia, and (4) pharmacologic analgesia alone (control). We studied these groups with regard to the relief of postoperative pain during the first 24 hours. For each patient we recorded the following: demographic characteristics; vital signs; intensity of pain with a visual analogue scale (VAS) before treatment (VAS(0)), at the 12th hour (VAS(12)), and at the 24th hour (VAS(24)); and analgesic intake.
The groups were comparable with respect to age, sex, and body mass index at baseline. Mean VAS scores decreased within each group; however, the mean VAS(12) and VAS(24) scores decreased significantly in the CTENS and ITENS groups, compared with PTENS and control groups (P < .05). We found no significant difference between the CTENS and ITENS groups with respect to decreasing VAS(12) and VAS(24) scores (P > .05). Narcotic intake was significantly less in the CTENS and ITENS groups than in the control and PTENS groups (P < .01). Furthermore, narcotic requirements were significantly lower in the CTENS group than in the ITENS group (P < .01).
CTENS and ITENS after median sternotomy for CABG decreased pain and reduced narcotic requirements more than in the PTENS and control treatments during first postoperative 24 hours. Neither CTENS nor ITENS is superior to the other in decreasing pain; however, CTENS leads to a greater reduction in the narcotic requirement than ITENS.
- SourceAvailable from: Gaspar R Chiappa[Show abstract] [Hide abstract]
ABSTRACT: We tested the hypothesis that transcutaneous electrical nerve stimulation (TENS) over the stellate ganglion region would reduce sympathetic over-stimulation and improve femoral blood flow (FBF) after coronary artery bypass graft (CABG) surgery. Thirty-eight patients (20 males, 24 NYHA class III-IV) were randomized to 5-days post-operative TENS (n = 20; 4 times/day; 30 min/session) or sham TENS (n = 18) applied to the posterior cervical region (C7-T4). Sympathetic nervous system was stimulated by the cold pressor test with FBF being measured by ultrasound doppler. Femoral vascular conductance (FVC) was calculated as FBF/mean arterial pressure (MAP). 6-min walking distance established patients' functional capacity. Before and after the intervention periods, pain scores, opiate requirements and circulating β-endorphin levels were determined. As expected, pre-operative MAP increased and FBF and FVC decreased during the cold pressor test. Sham TENS had no significant effect on these variables (p>0.05). In contrast, MAP decreased in the TENS group (125 ± 12 mmHg vs. 112 ± 10 mmHg). This finding in association with a consistent increase in FBF (95 ± 5 mL/min vs. 145 ± 14 mL/min) led to significant improvements in FVC (p<0.01). Moreover, 6-min walking distance improved only with TENS (post-pre= 35 ± 12 m vs. 6 ± 10 m; p<0.01). TENS was associated with lesser post-operative pain and opiate requirements but greater circulating β-endorphin levels (p<0.05). In conclusion, stellate ganglion TENS after CABG surgery positively impacted on limb blood flow during a sympathetic stimulation maneuver, a beneficial effect associated with improved clinical and functional outcomes.Journal of applied physiology (Bethesda, Md. : 1985). 08/2014;
- [Show abstract] [Hide abstract]
ABSTRACT: The use of transcutaneous electrical nerve stimulation (TENS) as non-pharmacological therapeutic modality is increasing. The types of TENS used clinically are conventional TENS, acupuncture TENS and intense TENS. Their working is believed to be based on gate control theory of pain and activation of endogenous opioids. TENS has been used in anaesthesia for treatment of post-operative analgesia, post-operative nausea vomiting and labour analgesia. Evidence to support analgesic efficacy of TENS is ambiguous. A systematic search of literature on PubMed and Cochrane Library from July 2012 to January 2014 identified a total of eight clinical trials investigating post-operative analgesic effects of TENS including a total of 442 patients. Most of the studies have demonstrated clinically significant reduction in pain intensity and supplemental analgesic requirement. However, these trials vary in TENS parameters used that is, duration, intensity, frequency of stimulation and location of electrodes. Further studies with adequate sample size and good methodological design are warranted to establish general recommendation for use of TENS for post-operative pain.Indian journal of anaesthesia 07/2014; 58(4):388-93.