Effect of transcutaneous electrical acupoint stimulation on postoperative analgesia after ureteroscopic lithotripsy: a randomized controlled trial

Effect of Transcutaneous Electrical Acupoint Stimulation on Extubation-Related Stress Response in Noncardiac Surgery Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

Stress response is a common complication during extubation, mainly manifested by dramatic hemodynamic fluctuations. Transcutaneous electrical acupoint stimulation (TEAS) is widely applied in the perioperative period. We performed this meta-analysis to evaluate whether the TEAS could relieve the stress response during extubation in noncardiac surgery patients.

DESIGN

A systematic review and meta-analysis of randomized controlled trials.

METHODS

We searched six databases (PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure, CNKI, and Wan Fang) for relevant literature. A risk of bias assessment was executed based on the Cochrane Criteria. We applied RevMan5.4.1 software to analyze data. When the χ2 test did not show heterogeneity, we adopted the fixed-effect model. Otherwise, the random-effect model was used.

FINDINGS

ln total, 12 randomized controlled trials with 1,347 participants were enrolled in this meta-analysis. Meta-analysis showed the heart rate and mean arterial pressure of the intervention group were significantly lower than the control group at immediately, 5 minutes, and 10 minutes after extubation. The occurrence rate of emergency agitation (RR 0.39, 95% CI [0.26,0.60]) and postoperative delirium (RR 0.40, 95% CI [0.22, 0.72] were also lower in the TEAS group. The consumption of propofol (standardized mean difference (SMD) 0.47, 95% CI [-0.77, -0.18]) and remifentanil (SMD 1.49, 95% CI [-2.01, -0.96]) of the intervention group were also significantly reduced compared with the control group.

CONCLUSIONS

TEAS was beneficial for improving stress response during extubation, emergence agitation, postoperative delirium, and reduced the consumption of intraoperative propofol and remifentanil, but it was necessary to note the limitations of the current evidence.

Effect of transcutaneous electrical acupoint stimulation on postoperative pain in pediatric orthopedic surgery with the enhanced recovery after surgery protocol: a prospective, randomized controlled trial

STUDY OBJECTIVE

To evaluate the safety and effectiveness of transcutaneous electrical acupoint stimulation (TEAS) in postoperative analgesia following pediatric orthopedic surgery with the enhanced recovery after surgery (ERAS) protocol.

DESIGN

Prospective randomized controlled trial.

SETTING

The Seventh Medical Center of the Chinese People's Liberation Army General Hospital.

PARTICIPANTS

Eligible participants were children aged 3-15 years who were scheduled to undergo orthopedic surgery of the lower extremities under general anesthesia.

INTERVENTIONS

A total of 58 children were randomly allocated into two groups: TEAS (n = 29) and sham-TEAS (n = 29). The ERAS protocol was used in both groups. In the TEAS group, the bilateral Hegu (LI4) and Neiguan (PC6) acupoints were stimulated starting from 10 min before anesthetic induction until the completion of surgery. In the sham-TEAS group, the electric stimulator was also connected to the participants; however, electrical stimulation was not applied.

MEASURES

The primary outcome was the severity of pain before leaving the post-anesthesia care unit (PACU) and at postoperative 2 h, 24 h, and 48 h. Pain intensity was measured with the Faces Pain Scale-Revised (FPS-R).

RESULTS

None of the participants had any TEAS-related adverse reactions. In comparison with the sham-TEAS group, FPS-R scores in the TEAS group were significantly decreased before leaving the PACU and at postoperative 2 h and 24 h (p < 0.05). The incidence of emergence agitation, intraoperative consumption of remifentanil, and time to extubation were significantly reduced in the TEAS group. Furthermore, the time to first press of the patient-controlled intravenous analgesia (PCIA) pump was significantly longer, the pressing times of the PCIA pump in 48 h after surgery was significantly decreased, and parental satisfaction was significantly improved (all p < 0.05).

CONCLUSION

TEAS may safely and effectively relieve postoperative pain and reduce the consumption of perioperative analgesia in children following orthopedic surgery with the ERAS protocol.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200059577), registered on May 4, 2022.

Non-invasive neuromodulation: an emerging intervention for visceral pain in gastrointestinal disorders

Gastrointestinal (GI) disorders, which extend from the esophagus to the anus, are the most common diseases of the GI tract. Among these disorders, pain, encompassing both abdominal and visceral pain, is a predominant feature, affecting the patients' quality of life and imposing a substantial financial burden on society. Pain signals originating from the gut intricately shape brain dynamics. In response, the brain sends appropriate descending signals to respond to pain through neuronal inhibition. However, due to the heterogeneous nature of the disease and its limited pathophysiological understanding, treatment options are minimal and often controversial. Consequently, many patients with GI disorders use complementary and alternative therapies such as neuromodulation to treat visceral pain. Neuromodulation intervenes in the central, peripheral, or autonomic nervous system by alternating or modulating nerve activity using electrical, electromagnetic, chemical, or optogenetic methodologies. Here, we review a few emerging noninvasive neuromodulation approaches with promising potential for alleviating pain associated with functional dyspepsia, gastroparesis, irritable bowel syndrome, inflammatory bowel disease, and non-cardiac chest pain. Moreover, we address critical aspects, including the efficacy, safety, and feasibility of these noninvasive neuromodulation methods, elucidate their mechanisms of action, and outline future research directions. In conclusion, the emerging field of noninvasive neuromodulation appears as a viable alternative therapeutic avenue for effectively managing visceral pain in GI disorders.

Efficacy and safety of electrical acupoint stimulation for postoperative nausea and vomiting: A systematic review and meta-analysis

BACKGROUND

Postoperative nausea and vomiting are typical postsurgical complications. Drug therapy is only partially effective. The goal of our meta-analysis is to systematically evaluate the efficacy and safety of electrical acupoint stimulation for postoperative nausea and vomiting and to score the quality of evidence supporting this concept.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov were searched from inception to March 19, 2020.

RESULTS

Twenty-six studies (2064 patients) were included. Compared with control treatment, electrical acupoint stimulation reduced the incidence of postoperative nausea and vomiting (RR 0.49, 95% CI 0.41 to 0.57, P < 0.001), postoperative nausea (RR 0.55, 95% CI 0.47 to 0.64, P < 0.001) and postoperative vomiting (RR 0.56, 95% CI 0.45 to 0.70, P < 0.001). Electrical acupoint stimulation also reduced the number of patients requiring antiemetic rescue (RR 0.60, 95% CI 0.43 to 0.85, P = 0.004). No differences in adverse events were observed. Subgroup analysis showed that both electroacupuncture (RR 0.58, 95% CI 0.46 to 0.74, P < 0.001) and transcutaneous electrical acupoint stimulation (RR 0.44, 95% CI 0.34 to 0.58, P < 0.001) had significant effects. Electrical acupoint stimulation was effective whether administered preoperatively (RR 0.40, 95% CI 0.27 to 0.60, P < 0.001), postoperatively (RR 0.59, 95% CI 0.46 to 0.76, P < 0.001), or perioperatively (RR 0.50, 95% CI 0.37 to 0.67, P < 0.001). The quality of evidence was moderate to low.

CONCLUSIONS

Electrical acupoint stimulation probably reduce the incidence of postoperative nausea and vomiting, postoperative nausea, postoperative vomiting, and reduce the number of patients requiring antiemetic rescue, with few adverse events.

Transcutaneous electrical acupoint stimulation for suspected laryngopharyngeal reflux disease

PURPOSE

To determine the efficacy of transcutaneous electrical acupoint stimulation (TEAS) combined with proton pump inhibitor (PPI) therapy on symptoms and signs of patients with suspected laryngopharyngeal reflux disease (LPRD).

METHODS

This was a prospective randomized controlled study. Seventy patients with reflux symptom index (RSI) > 13 and reflux finding score (RFS) > 7 were recruited and received PPI alone (control group) or TEAS combined with PPI (experimental group) for 12 weeks. Patients in the experimental group received TEAS at Tiantu (RN22), Renying (ST9), and Neiguan (PC6) once a day, five times a week. RSI, RFS, throat pain visual analog score (VAS), and LPR-health-related quality-of-life (LPR-HRQL) scores were evaluated at baseline and after 4 and 12 weeks.

RESULTS

The decreases in total RSI and RFS, along with several subscores, were significantly higher in the experimental group than in the control group after 12 weeks (P < 0.05). The throat pain VAS and LPR-HRQL scores decreased significantly at 4 and 12 weeks after treatment in both groups, with significant differences between the groups (P < 0.001). No severe adverse events occurred, and the rates of adverse events were similar between the two groups.

CONCLUSION

Compared with PPI alone, TEAS combined with PPI showed a significantly greater improvement in symptoms, signs, and quality of life in the treatment of LPRD without increasing the occurrence of adverse effects. Therefore, TEAS could serve as a useful and safe treatment method for LPRD.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2100046755.

Effects of transcutaneous electrical acupoint stimulation on gastrointestinal dysfunction after gastrointestinal surgery: A meta-analysis

BACKGROUND

Postoperative gastrointestinal dysfunction (PGD) is a common complication in patients undergoing gastrointestinal surgery. Several studies have evaluated the effect of transcutaneous electrical acupoint stimulation (TEAS) on PGD, so we conducted a systematic review and meta-analysis to better understand these studies methodologic limitations and summarize clinical effects.

METHODS

Articles (published from January 2010 to April 2022) were searched from the following databases: Wanfang Database, China National Knowledge Infrastructure (CNKI), Cochrane Library, PubMed, Web of Science and Embase. Two authors conducted literature selection, data extraction and statistical analysis independently. This meta-analysis used RevMan 5.4 software to implement statistical analysis and applied Cochrane bias risk tool to assess methodologic weaknesses of included articles. We assessed the effect of TEAS on time to first flatus, first defecation and bowel sound recovery through meta-analyses using a random-effects model.

RESULTS

The meta-analysis included 10 articles including 1497 patients. This study showed that TEAS could effectively promote postoperative gastrointestinal function recovery by analyzing the time to first flatus (MD-14.81 h, 95% CI -15.88 to -13.75 h), time to first defecation (MD-14.68 h, 95% CI -20.59 to -8.76 h), time to bowel sound recovery (MD-5.79 h, 95% CI -10.87 to -0.71 h), length of hospital stay (MD-1.48d, 95% CI -1.86 to -1.11d), and the incidence of postoperative nausea and vomiting (PONV) (OR 0.41, 95% CI 0.29-0.58). In addition, we assessed the quality of the articles and found small sample sizes and lower methodological quality in some articles.

CONCLUSION

Our meta-analysis revealed that TEAS could be a nonpharmacological treatment for PGD in patients after gastrointestinal surgery. However, positive findings should be treated carefully and future studies with high quality and large samples are needed to support this results.

Clinical efficacy of acupuncture for pain relief from renal colic: A meta-analysis and trial sequence analysis

Background

This meta-analysis aimed at investigating the efficacy of acupuncture for relieving renal colic and reducing the risk of analgesic-related complications.

Methods

Randomized controlled trials (RCTs) comparing the efficacy of acupuncture (acupuncture group) with conventional interventions (control group) were screened from MEDLINE, EMBASE, Cochrane library databases, China Knowledge Network (CNKI), and Airiti Library till July 15, 2022. The primary outcome was the rate of effective pain relief (response rate), while secondary outcomes included the time of onset of pain relief, visual analog scale (VAS) at 30-60 min and risk of side effects.

Results

Thirteen eligible studies involving 1,212 participants published between 1992 and 2021 were analyzed. Compared with the control group, patients receiving acupuncture had a higher overall response rate [risk ratio (RR) = 1.12, 95% CI: 1.05-1.19, p = 0.0002, I ² = 41%, 1,136 patients] (primary outcome) and a faster pain relief [MD = -10.74 min, 95% CI: -12.65 to -8.82, p < 0.00001, I ² = 87%, 839 patients]. Patients receiving acupuncture had a lower pain score [MD = -0.65, 95% CI: -1.09 to -0.21, p = 0.21, I ² = 55%, 327 patients] and risk of side effects (RR = 0.11, 95% CI: 0.04-0.26, p < 0.00001, I ² = 0, 314 patients) compared to those receiving conventional interventions. Results from trial sequence analysis revealed sufficient evidence supporting the beneficial effects of acupuncture on response rate, time to pain relief, and pain score at 30-60 min.

Conclusion

Compared with conventional analgesic-based interventions, acupuncture can more efficiently relieve renal colic with fewer adverse effects. The limited number and quality of included studies warrant more clinical RCTs to support our findings.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022346714.

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.

Different interventions for preventing postoperative catheter-related bladder discomfort: a systematic review and meta-analysis

OBJECTIVE

Catheter-related bladder discomfort (CRBD) is a common complication of intraoperative urinary catheterization. Various studies have evaluated the efficacy of different interventions in postoperative CRBD. The present review was performed to assess the efficacy of these interventions.

METHODS

PubMed, Embase, and CENTRAL (Cochrane Central Register of Controlled Trials) databases were systematically searched to identify randomized controlled trials (RCTs) investigating the efficacy of different drugs for the prevention of postoperative CRBD. This review evaluated the incidence and severity of CRBD after different interventions at 0, 1, 2, and 6 h postoperatively.

RESULTS

Forty-five studies including 31 different drugs were analyzed. Eleven drugs were investigated in more than two RCTs, of which dexmedetomidine, gabapentin, tolterodine, tramadol, ketamine, nefopam, oxybutynin, pregabalin, and pudendal nerve block (PNB) generally showed significantly higher efficacy than controls postoperatively. Solifenacin only showed significant efficacy compared with the control at 0 h, and intravenous lidocaine only showed significant efficacy compared with the control at 6 h. There were insufficient trials to draw conclusions regarding atropine, butylscopolamine, chlorpheniramine, clonidine, darifenacin, diphenhydramine, glycopyrrolate, intravesical bupivacaine, ketamine-haloperidol, pethidine-haloperidol, ketorolac, lidocaine-prilocaine cream, magnesium, hyoscine n-butyl bromide, oxycodone, paracetamol, parecoxib, trospium, resiniferatoxin, or amikacin. However, all but pethidine-haloperidol and chlorpheniramine showed some efficacy at various time points compared with controls.

CONCLUSION

This review suggests that dexmedetomidine, gabapentin, tolterodine, tramadol, ketamine, nefopam, oxybutynin, pregabalin, and PNB are effective in preventing postoperative CRBD. Considering the efficacy and adverse effects of all drugs, dexmedetomidine and gabapentin were ranked best.

Cerebral mechanism of opposing needling for managing acute pain after unilateral total knee arthroplasty: study protocol for a randomized, sham-controlled clinical trial

Background

Opposing needling is a unique method used in acupuncture therapy to relieve pain, acting on the side contralateral to the pain. Although opposing needling has been used to treat pain in various diseases, it is not clear how opposing needling affects the activity of the central nervous system to relieve acute pain. We herein present the protocol for a randomized sham-controlled clinical trial aiming to explore the cerebral mechanism of opposing needling for managing acute pain after unilateral total knee arthroplasty (TKA).

Methods

This is a randomized sham-controlled single-blind clinical trial. Patients will be allocated randomly to two parallel groups (A: opposing electroacupuncture group; B: sham opposing electroacupuncture group). The Yinlingquan (SP9), Yanglingquan (GB34), Futu (ST32), and Zusanli (ST36) acupoints will be used as the opposing needling sites in both groups. In group A, the healthy lower limbs will receive electroacupuncture, while in group B, the healthy lower limbs will receive sham electroacupuncture. At 72 h after unilateral TKA, patients in both groups will begin treatment once per day for 3 days. Functional magnetic resonance imaging will be performed on all patients before the intervention, after unilateral TKA, and at the end of the intervention to detect changes in brain activity. Changes in pressure pain thresholds will be used as the main outcome for the improvement of knee joint pain. Secondary outcome indicators will include the visual analogue scale (including pain during rest and activity) and a 4-m walking test. Surface electromyography, additional analgesia use, the self-rating anxiety scale, and the self-rating depression scale will be used as additional outcome indices.

Discussion

The results will reveal the influence of opposing needling on cerebral activity in patients with acute pain after unilateral TKA and the possible relationship between cerebral activity changes and improvement of clinical variables, which may indicate the central mechanism of opposing needling in managing acute pain after unilateral TKA.

Trial registration

Study on the brain central mechanism of opposing needling analgesia after total kneearthroplasty based on multimodal MRI ChiCTR2100042429. Registered on January 21, 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06066-6.

Comparative analysis of two laser wavelengths in the stimulation of acupuncture points for analgesic effects in an animal model

This study compares the effectiveness of two laser wavelengths for stimulating acupoints in an experimental model of acute postoperative pain. Forty-five Wistar rats were randomly assigned to receive treatment on their left hind paw, contralateral to a surgical procedure. Laser treatments were performed with Green Laser-GL (532 nm, 70 mW and 7 J/cm² of energy), Red Laser-RL (660 nm, 100 mW and 7 J/cm² of energy), or with Laser Off-LO. After each application, the animals were evaluated with a Von Frey analgesiometer to check for painful sensitivity on their right (with surgery) and left (without surgery) hind paws. Neuropeptides and cytokine levels in the incision site tissue of the right paw were measured by ELISA after 1, 6 and 24 hours. It was possible to observe that, in this pain model, both lasers promoted analgesia and that the GL altered the levels of TNF-α and IL-1β.

Effects of Transcutaneous Electrical Acupoint Stimulation on Systemic Inflammatory Response Syndrome of Patients after Percutaneous Nephrolithotomy: A Randomized Controlled Trial

Purpose

Transcutaneous electrical acupoint stimulation (TEAS) is widely used. However, no study evaluated TEAS on systemic inflammatory response syndrome (SIRS) of patients after percutaneous nephrolithotomy (PCNL). The study was to evaluate TEAS on SIRS of patients after PCNL.

Methods

67 patients were enrolled and divided into group TEAS and group sham TEAS. Data were collected from 60 participants finally. In the study, TEAS or sham TEAS on bilateral Shenshu (BL23), Yinlingquan (SP9), Hegu (LI4), and Neiguan (PC6) was performed continuously throughout the procedure. The primary outcome included the incidence of systemic inflammatory response syndrome (SIRS) within 48 h after surgery. The secondary outcomes included the serum levels of inflammatory cytokines, hemodynamics changes, complications, and hospital stay after surgery. The serum levels of tumor necrosis factor- (TNF-) α and interleukin- (IL-) 6, mean arterial pressure (MAP), and heart rate (HR) at 30 min before anesthesia (T₀), the time after surgery (T₁), 24 h postoperation (T₂), and 48 h postoperation (T₃) were recorded. The consumption of analgesic during surgery was also recorded, as well as the complications and duration of hospital stay after PCNL.

Results

The incidence of SIRS in group TEAS was lower than group sham TEAS (30% vs. 6.67%, p=0.023). Compared with the sham TEAS group, both levels of TNF-α and IL-6 at T₁, T₂, and T₃ were lower in the TEAS group (p < 0.05). The levels of MAP and HR in sham TEAS at T₁, T₂, and T₃ were markedly higher than that in the TEAS group (p < 0.05). The total consumption of propofol and remifentanil during surgery in group TEAS was lower than that in the sham TEAS group. The incidence of hypotension, hypertension, emergence agitation, and postoperative nausea and vomiting (PONV) was also lower in group TEAS after PCNL (p < 0.05).

Conclusions

TEAS could effectively reduce the incidence of SIRS and inflammatory cytokines for patients who underwent PCNL. In addition, TEAS helped to maintain the hemodynamic stability and cut down the consumption of analgesics during PCNL, reducing the complications after PCNL.

Correlated Sensory and Sympathetic Innervation Between the Acupoint BL23 and Kidney in the Rat

Objective: To investigate the sensory and sympathetic innervations associated with both acupoint “Shenshu” (BL23) and kidney in the rat for insight into the neuronal correlation between the Back-Shu Point and its corresponding visceral organ.

Methods: The BL23 and kidney were selected as the representative acupoint and visceral organ in this study, in which their local nerve fibers were examined by using double fluorescent immunohistochemistry with calcitonin gene-related peptide (CGRP) and tyrosine hydroxylase (TH). Meanwhile, their neuronal correlation in the dorsal root ganglia (DRGs), spinal cord, and sympathetic (paravertebral) chain were investigated using a double fluorescent neural tracing technique with Alexa Fluor 488 and 594 conjugates with cholera toxin subunit B (AF488/594-CTB).

Results: The local tissue of acupoint BL23 and the fibrous capsule of kidney distributed abundantly with CGRP- and TH-positive nerve fibers, corresponding to their sensory and sympathetic innervation. On the other hand, the sensory neurons associated with acupoint BL23 and kidney were labeled with AF488/594-CTB and distributed from thoracic (T) 11 to lumbar (L) 3 DRGs and from T10 to L2 DRGs, respectively, in which some of them in T12-T13 DRGs were simultaneously labeled with both AF488/594-CTB. Also, postganglionic neurons associated with both acupoint BL23 and kidney were found in the sympathetic chain at the same spinal segments but separately labeled with AF488-CTB and AF594-CTB.

Conclusion: Our study demonstrates the neural characteristics of the acupoint BL23 and kidney in the rat from the perspective of neurochemistry and neural pathways, providing an example for understanding the neuronal correlation between the Back-Shu Points and their corresponding visceral organs. These results suggest that the stimulation of the Back-Shu Points may regulate the activities of the target-organs via the periphery sensory and sympathetic pathways.

Effects of transcutaneous electrical acupoint stimulation on perioperative immune function and postoperative analgesia in patients undergoing radical mastectomy: A randomized controlled trial

Radical mastectomy may lead to suppression of cellular immune function in patients with malignant tumors. Transcutaneous electrical acupoint stimulation (TEAS) is widely used in clinical practice. However, there have been relatively few studies on the effects of TEAS on postoperative analgesia and immune function. The present study aimed to evaluate the effects of TAES on postoperative pain and immune function in patients undergoing radical mastectomy. A total of 65 patients were enrolled and allocated to either receive TEAS or sham TEAS. TEAS was implemented on bilateral Hegu (LI4), Neiguan (PC6) and Zusanli (ST36) acupoints simultaneously for 30 min before induction of anesthesia at 4 and 12 h post-operation. The primary outcomes included visual analogue scale (VAS) scores at 4 h (T₁), 12 h T₂), 24 h (T₃) and 48 h (T₄) post-operation, and serum levels of IL-2, IL-4, IFN-γ and the IL-2/IL-4 ratio at 30 min before TEAS (T₀), T₁, T₂, T₃ and T₄. Secondary outcomes included the cumulative time of rescue analgesia within 48 h post-surgery, as well as the incidence of postoperative nausea and vomiting (PONV) and pruritus. Compared with the sham TEAS group, postoperative VAS scores at T₂ and T₃, the total consumption of opioids in the patient-controlled analgesia (PCA) pump, pressing times of the PCA pump and the incidences of PONV and headache were significantly lower in the TEAS group. The serum levels of IFN-γ at T₃ and T₄, and the serum levels of IL-2 and the IL-2/IL-4 ratio at T₂, T₃ and T₄ were higher in the TEAS group compared with the sham TEAS group. By contrast, the serum levels of IL-4 were lower at T₂, T₃ and T₄ in the TEAS group compared with the sham TEAS group. The results indicated that TEAS could improve postoperative analgesia, reduce postoperative consumption of opioids and alleviate postoperative side effects. Simultaneously, TEAS was able to reverse decreased serum levels of IL-2 and IFN-γ, reduce the level of IL-4 and restore the balance of Th1/Th2, thereby partially attenuating perioperative immune function depression in patients with breast cancer. The current trial was registered prior to participant enrollment at www.chictr.org.cn (Clinical Trial no. ChiCTR1800017768).

Efficacy of different-frequency TEAS on acute pain after the total knee arthroplasty: a study protocol for a parallel group randomized trial

BACKGROUND

Total knee arthroplasty (TKA) is an optimal option for patients with middle-to-end-stage knee osteoarthritis. However, the management of postoperative acute pain remains inefficient. Transcutaneous electrical acupoint stimulation (TEAS) is a nonpharmacological method to manage postoperative acute pain. Different frequencies of TEAS have been tested using varying parameters, but the optimal analgesic frequency remains controversial. The aim of this study was to explore the optimal analgesic frequency of TEAS for treating acute pain after the primary unilateral TKA.

METHODS/DESIGN

This is a double-blind, randomized controlled trial. A total of 156 patients are randomly assigned to: G1, 5 Hz TEAS; G2, 100 Hz TEAS; G3, mixed TEAS (alternative use of daily 5 Hz and 100 Hz TEAS) and G4, placebo TEAS. In the G1, G2 and G3 groups, TEAS is conducted at acupoints SP9 and GB34 of the leg that was operated on (at a wave of continuous, balanced and asymmetrical biphasic square, with a pulse width of 200 μs, and a strong but comfortable current) for 30 min prior to a 30-min rehabilitation session per day for 2 weeks. In G4 group, TEAS is delivered at a strong but comfortable current for 30 s, then the current is gradually decreased to none over the next 15 s. The primary outcomes are measured before surgery, at baseline (POD 3, before TEAS intervention), week 1 and 2 after TEAS intervention with the Numeric Pain Rating Scale and The American Knee Society Score. The secondary outcomes include: (1) Active range of motion of the knee that was operated on; (2) Surface electromyography of both quadriceps; (3) Modified 30-s sit to stand test; (4) Additional usage of analgesia; and (5) SF-36. The additional outcomes include: (1) Patients' satisfaction rate; (2) Patient's expectation rate; and (3) Incidence of analgesia-related side effects. To test the blinding of participants and assessors, they are asked to guess whether the subjects received active or placebo TEAS within 5 min after the latest intervention. The safety and financial cost of TEAS are assessed.

DISCUSSION

Mixed TEAS has more favorable effect on acute pain control than the placebo or 5 Hz or 100 Hz TEAS.

TRIAL REGISTRATION

ChiCTR1800016347 . Date of registration was 26 May 2018. Retrospectively registered.