High-frequency, high-intensity transcutaneous electrical nerve stimulation compared with opioids for pain relief after gynecological surgery: a systematic review and meta-analysis.

OBJECTIVES: Opioids are important for postoperative analgesia but their use can be associated with numerous side effects. Transcutaneous electrical nerve stimulation (TENS) has been used for acute pain treatment and has dose-dependent analgesic effects, and therefore presents an alternative to intravenous (iv) opioids for postoperative pain relief. The aim of this meta-analysis was to compare high-frequency, high-intensity (HFHI or intense) TENS to iv opioids with regard to postoperative pain intensity, recovery time in the Post Anesthesia Care Unit (PACU) and opioid consumption after elective gynecological surgery. METHODS: We searched Medline, Embase, Web of Science, Cochrane, Amed and Cinahl for RCTs and quasi-experimental studies (2010-2022), and WHO and ClinicalTrials.gov for ongoing/unpublished studies. Meta-analysis and subsequent Trial Sequential Analysis (TSA) was performed for all stated outcomes. Quality of evidence was assessed according to GRADE. RESULTS: Only three RCTs met the inclusion criteria (362 participants). The surgical procedures involved surgical abortion, gynecologic laparoscopy and hysteroscopy. The applied TENS frequency was 80 Hz and intensity 40-60 mA. There was no difference in pain intensity according to Visual Analogue Scale (VAS) at discharge from PACU between the TENS and opioid group (MD VAS -0.15, 95 % CI -0.38 to 0.09) (moderate level of evidence). Time in PACU was significantly shorter in the TENS group (MD -15.2, 95 % -22.75 to -7.67), and this finding was manifested by TSA (high-level of evidence). Opioid consumption in PACU was lower in the TENS group (MD Morphine equivalents per patient mg -3.42, 95 % -4.67 to -2.17) (high-level of evidence). CONCLUSIONS: There was no detectable difference in postoperative pain relief between HFHI TENS and iv opioids after gynecological surgery. Moreover, HFHI TENS decreases recovery time and opioid consumption in PACU. HFHI TENS may be considered an opioid-sparing alternative for postoperative pain relief after gynecological surgery. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021231048.

Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after hysteroscopy: a randomized controlled study.

OBJECTIVE: To compare the time spent in the Post-Anesthesia Care Unit (PACU) and the pain-relieving effects of treatment with high-frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) opioids after hysteroscopy. METHODS: All patients who postoperatively reported a visual analogue scale (VAS) pain score of ≥3 were included in the study. TENS treatment was given with a stimulus intensity between 40 and 60 mA for 1 minute and repeated once if there was insufficient pain relief. In the opioid group, a fractionated dose of 5 mg morphine was administered. If the patient reported insufficient pain relief after the assigned treatment, the patient was reassigned to the other treatment group. RESULTS: Seventy-four women were randomized to TENS (n=38) or IV opioids (n=36) for treatment. Both groups reported significant pain relief after discharge from the PACU, with a decrease of VAS scores from 5.6 to 1.4 in the TENS group (P<0.001) and 5.1 to 1.3 in the opioid group (P<0.001). There were no significant differences between the groups. When only the responders in both groups, i.e., patients with VAS scores of <3 on respectively assigned treatments, were compared, the TENS responders (n=22) were found to have spent a significantly shorter time in the PACU (91 vs. 69 minutes, P=0.013) compared to the opioid responders (n=20). CONCLUSION: Using TENS as first line of pain relief may reduce the need for postoperative opioids. In addition, TENS appears preferable as the first line of treatment due to its association with a shorter time spent in the PACU if the patient responds to the treatment. TRIAL REGISTRATION: Västra Götalandsregionen Identifier: 211261.

Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after gynecologic laparoscopic surgery: a randomized controlled study.

BACKGROUND: The aim of the study was to compare the pain relieving effect and the time spent in the recovery unit after treatment with high frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) opioids after gynecologic laparoscopic surgery. METHODS: All patients who postoperatively reported visual analogue scale (VAS) pain score ≥ 3 were consecutively included in the study. The TENS treatment was given with a stimulus intensity between 40-60 mA during 1 minute, repeated once if insufficient pain relief. In the opioid group, a maximum dose of 10 mg morphine was given IV. If the patient reported insufficient pain relief (VAS ≥ 3) on the assigned treatment, the patient crossed over to the other treatment group. RESULTS: Ninety-three women were randomized to TENS (n = 47) or IV opioids (n = 46). Both groups reported significant pain relief at leave from the recovery unit (TENS group: VAS 5.4 to 1.0, P < 0.001; IV opioid group: VAS 5.2 to 1.1, P < 0.001) with no differences between the groups. When only responders, i.e. patients with VAS < 3 after assigned treatment, were compared the TENS responders spent significantly shorter time in the recovery unit (90 vs. 122 minutes, P = 0.008) compared to the responders in the opioid group. CONCLUSIONS: TENS and IV opioids are both effective treatments for pain relief after gynecologic laparoscopic surgery. TENS seems to be preferable for first choice of treatment as the treatment is associated with shorter time spent in recovery unit if the patient responds to the treatment.

Health information: what can mobile phone assessments add?

In healthcare, pain assessment is a key factor in effectively treating postoperative pain and reducing the risk of developing chronic pain. The overall aim of this study was to investigate whether a mobile phone support system can be used as a basis to continuously document patients' health information in real time and provide conditions for optimal, individual pain management after cholecystectomy and hysterectomy procedures.In this pilot study, two randomly selected groups of patients provided information about their pain for one week postoperatively. One group responded via cell phones, and the other, a control group, responded using paper-based questionnaires.The mobile phone system was found to provide a fast and safe basis for reporting pain postoperatively in real time. The results indicate that on days 3 and 4 the mobile phone group reported significantly higher levels of pain than the control group, and the cholecystectomy patients reported significantly more pain at movement on days 3 and 4 than the hysterectomy patients.The mobile phone approach is an adaptation to modern technology and the mobility of individuals. This technology is user friendly and requires minimal support. However, as the sample size was small (n = 37), further studies are needed before additional conclusions can be drawn.