Efficacy of Transcutaneous Electronic Nerve Stimulation in Postoperative Analgesia After Pulmonary Surgery: A Systematic Review and Meta-Analysis

Practice Advisory for Postoperative Pain Management of Thoracic Surgical Patients: A Report from the Society of Cardiovascular Anesthesiologists

Pain after thoracic surgery is often significant, which can disrupt normal respiratory mechanics and impair the clearance of secretions, thus increasing the risk of postoperative respiratory complications. Poorly controlled acute pain can lead to persistent post-thoracotomy pain and continued opioid use that can affect quality of life. With the increased awareness of opioid-associated adverse effects and recent emphasis on enhanced recovery, opioid-sparing multimodal analgesia has been used widely for acute pain management after thoracic surgery. This practice advisory reviews, evaluates, and summarizes the recent literature related to pharmacological therapies and non-pharmacological therapies used for postoperative pain management after thoracic surgery and offers guidance to providers in making appropriate pain management decisions for their patients.

Effect of Transcutaneous Electrical Nerve Stimulation on Patients with Total Knee Replacement: A Randomized Controlled Trial

PURPOSE

The aim of this study was to determine the effect of transcutaneous electrical nerve stimulation (TENS) on pain, functionality, quality of life, and analgesic consumption in patients undergoing TKR.

DESIGN

A single center, randomized controlled trial.

METHODS

A total of 52 participants were randomly assigned to the intervention (n = 26) and control (n = 26) groups. The intervention group was exposed to conventional TENS. Data were collected with a Patient Identification Form, the Visual Analogue Scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Quality of Life Scale (SF-36), and the Analgesic Tracking Form.

RESULTS

VAS and WOMAC scores significantly decreased in the intervention group, over time, while they increased in the control group. SF-36 scores significantly increased in the intervention group over time. It was determined that analgesic consumption was significantly lower in the intervention group than in the control group.

CONCLUSIONS

TENS significantly reduced pain and increased functionality and quality of life. Our findings suggest that TENS may be an effective adjunctive analgesic therapy in patients receiving TKR; however, more testing is needed in larger and more heterogeneous populations.

CLINICAL IMPLICATIONS

Nurses can provide effective postoperative pain control in patients undergoing TKR, increase functionality, accelerate the healing process, and improve their quality of life by using TENS, a non-pharmacological treatment method, in the perioperative period.

The Impact of Transcutaneous Electrical Nerve Stimulation (TENS) on Acute Pain and Other Postoperative Outcomes: A Systematic Review with Meta-Analysis

This study aimed to investigate the efficacy and safety of transcutaneous electrical nerve stimulation (TENS) in postoperative acute pain control. PubMed, Scopus, and Cochrane Library were searched on 1-8 December 2022, for randomized controlled trials on the analgesic effects of TENS. The outcomes were pain intensity and opioid use (primary), and postoperative (PO) adverse events, blood pressure, and the duration of hospital stay (secondary); PROSPERO CRD42022333335. A total of 40 articles were included in the meta-analysis. Pain intensity at rest and during coughing for all types of surgeries combined was lower in the TENS group (standardized mean difference (SMD) = -0.51 [-0.61, -0.41], p < 0.00001, 29 studies, and -1.28 [-2.46, -0.09], p-value = 0.03, six studies, respectively). There was a statistically significant decrease in morphine requirements, as well as in the incidence of postoperative nausea and vomiting, dizziness, and pruritus. There was no difference between the groups in postoperative pain intensity during walking, in blood pressure, and only a borderline difference in the length of hospital stay. The subgroup analysis by surgery type did not show significant differences between the groups in pain severity at rest. Thus, TENS has a potential for pain control and postoperative recovery outcomes.

Complementary Therapy Learning in the Setting of Lung Transplantation: A Single-Center Observational Study of Appropriation and Efficacy

Transplanted patients could benefit from complementary techniques. This prospective single-center, open study, performed in a tertiary university hospital, evaluates the appropriation and efficacy of a toolbox-kit of complementary techniques. Self-hypnosis, sophrology, relaxation, holistic gymnastics, and transcutaneous electric nerve stimulation (TENS) were taught to adult patients scheduled for double-lung transplantation. Patients were asked to use them before and after transplantation, as needed. The primary outcome was appropriation of each technique within the first three postoperative months. Secondary outcomes included efficacy on pain, anxiety, stress, sleep, and quality-of-life. Among the 80 patients included from May 2017 to September 2020, 59 were evaluated at the 4th postoperative month. Over the 4359 sessions performed, the most frequent technique used before surgery was relaxation. After transplantation, the techniques most frequently used were relaxation and TENS. TENS was the best technique in terms of autonomy, usability, adaptation, and compliance. Self-appropriation of relaxation was the easiest, while self-appropriation of holistic gymnastics was difficult but appreciated by patients. In conclusion: the appropriation by patients of complementary therapies such as mind-body therapies, TENS and holistic gymnastics is feasible in lung transplantation. Even after a short training session, patients regularly practiced these therapies, mainly TENS and relaxation.

Characterising the Features of 381 Clinical Studies Evaluating Transcutaneous Electrical Nerve Stimulation (TENS) for Pain Relief: A Secondary Analysis of the Meta-TENS Study to Improve Future Research

Background and Objectives: Characterising the features of methodologies, clinical attributes and intervention protocols, of studies is valuable to advise directions for research and practice. This article reports the findings of a secondary analysis of the features from studies screened as part of a large systematic review of TENS (the meta-TENS study). Materials and Methods: A descriptive analysis was performed on information associated with methodology, sample populations and intervention protocols from 381 randomised controlled trials (24,532 participants) evaluating TENS delivered at a strong comfortable intensity at the painful site in adults with pain, irrespective of diagnosis. Results: Studies were conducted in 43 countries commonly using parallel group design (n = 334) and one comparator group (n = 231). Mean ± standard deviation (SD) study sample size (64.05 ± 58.29 participants) and TENS group size (27.67 ± 21.90 participants) were small, with only 13 of 381 studies having 100 participants or more in the TENS group. Most TENS interventions were ‘high frequency’ (>10 pps, n = 276) and using 100 Hz (109/353 reports that stated a pulse frequency value). Of 476 comparator groups, 54.2% were active treatments (i.e., analgesic medication(s), exercise, manual therapies and electrophysical agents). Of 202 placebo comparator groups, 155 used a TENS device that did not deliver currents. At least 216 of 383 study groups were able to access other treatments whilst receiving TENS. Only 136 out of 381 reports included a statement about adverse events. Conclusions: Clinical studies on TENS are dominated by small parallel group evaluations of high frequency TENS that are often contaminated by concurrent treatment(s). Study reports tended focus on physiological and clinical implications rather than the veracity of methodology and findings. Previously published criteria for designing and reporting TENS studies were neglected and this should be corrected in future research using insights gleaned from this analysis.

Role of Transcutaneous Electric Nerve Stimulation in Pain and Pulmonary Function in Patients after Bariatric Surgery

Background

Changes in lifestyle, a carbohydrate-rich diet, and decreased physical activity are part of the context that led to an obesity pandemic. Treating obesity is a task that requires multidisciplinary care; however, in many cases, conventional therapy has no effect, requiring surgical intervention. This, in turn, is not without risks and causes important changes in lung function. Therefore, the aim of this study is to evaluate the effect of electroanalgesia through conventional transcutaneous electrical nerve stimulation (TENS) on the pain and lung function in the postoperative period of bariatric surgery.

Methods

This is a controlled and blinded clinical trial with 66 subjects who underwent bariatric surgery. The participants were randomized into 2 groups as follows: an intervention group treated with TENS (n = 33) and a placebo group (n = 33). The participants underwent 4 TENS sessions, and the effect on pain was assessed using a visual analogue scale (VAS pain). Lung function was measured by spirometry.

Results

There were no differences between the 2 groups regarding time of surgery and time of mechanical ventilation. Compared to placebo, TENS reduced pain in the intervention group (p = 0.001). Regarding the effect of electroanalgesia on pulmonary function, the spirometric parameters were similar between the groups. However, regarding muscle strength between the preoperative and postoperative periods, maximal inspiratory pressure (MIP) was maintained in the intervention group and decreased in the placebo group (p = 0.03). Compared with that in the intervention group, the respiratory rate in the placebo group increased during the application of TENS (p = 0.003).

Conclusion

Electroanalgesia reduces pain in patients who underwent bariatric surgery. Importantly, in these patients, the MIP is maintained between the preoperative and postoperative periods. However, electroanalgesia does not contribute to improvements in spirometric data. This trial is registered with NCT04800640.

Effects of Transcutaneous Electrical Nerve Stimulation on Mastectomy Pain, Patient Satisfaction, and Patient Outcomes

PURPOSE

Mastectomy is one of the most painful surgical procedures. Postoperative pain guidelines recommend transcutaneous electrical nerve stimulation (TENS) as a reliable non-pharmacological analgesic method. The aim of this study was to investigate the effects of TENS on postoperative pain and outcomes in patients undergoing modified radical mastectomy (MRM).

DESIGN

A single-center, single-blind, prospective, randomized-controlled study.

METHODS

This single-center, single-blind, randomized-controlled study included a total of 80 patients who underwent MRM at general surgery clinic of a tertiary center were included. The pain management of the patient outcomes were evaluated using the Turkish Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R-TR).

FINDINGS

The pain levels of the intervention group were lower than the control group. There were significant improvements in the patient outcomes such as mobilization, position, sleep, anxiety, and fear in the intervention group.

CONCLUSIONS

Our study results suggest that TENS reduces MRM pain. Thus, TENS can be recommended as a useful analgesic method in MRM.

Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses

Background and Objectives: Uncertainty about the clinical efficacy of transcutaneous electric nerve stimulation (TENS) to alleviate pain spans half a century. There has been no attempt to synthesise the entire body of systematic review evidence. The aim of this comprehensive review was to critically appraise the characteristics and outcomes of systematic reviews evaluating the clinical efficacy of TENS for any type of acute and chronic pain in adults. Materials and Methods: We searched electronic databases for full reports of systematic reviews of studies, overviews of systematic reviews, and hybrid reviews that evaluated the efficacy of TENS for any type of clinical pain in adults. We screened reports against eligibility criteria and extracted data related to the characteristics and outcomes of the review, including effect size estimates. We conducted a descriptive analysis of extracted data. Results: We included 169 reviews consisting of eight overviews, seven hybrid reviews and 154 systematic reviews with 49 meta-analyses. A tally of authors' conclusions found a tendency toward benefits from TENS in 69/169 reviews, no benefits in 13/169 reviews, and inconclusive evidence in 87/169 reviews. Only three meta-analyses pooled sufficient data to have confidence in the effect size estimate (i.e., pooled analysis of >500 events). Lower pain intensity was found during TENS compared with control for chronic musculoskeletal pain and labour pain, and lower analgesic consumption was found post-surgery during TENS. The appraisal revealed repeated shortcomings in RCTs that have hindered confident judgements about efficacy, resulting in stagnation of evidence. Conclusions: Our appraisal reveals examples of meta-analyses with 'sufficient data' demonstrating benefit. There were no examples of meta-analyses with 'sufficient data' demonstrating no benefit. Therefore, we recommend that TENS should be considered as a treatment option. The considerable quantity of reviews with 'insufficient data' and meaningless findings have clouded the issue of efficacy. We offer solutions to these issues going forward.