Acute Pain Reduction Research Articles

Effect of different electric stimulation modalities on pain and functionality of patients with pelvic pain: Systematic review with META-analysis.

Pelvic pain is located in the anterior abdominal wall, below the umbilical scar. Its treatment includes pharmacological therapy, which can cause adverse effects and is not always sufficient to control symptoms. Thus, the use of adjunct therapies such as electric stimulation has been suggested. Therefore, this review intends to appraise the literature on the effectiveness of electrostimulation in the treatment of pelvic pain. The search for studies was conducted until April 2024 in PubMed, Cochrane Library, ScienceDirect, SciELO, PEDro, CINAHL, BVS, Web of Science, Scopus, and Google Scholar databases using a combination of Mesh terms "Electric Stimulation" and "Pelvic Pain." Risk of bias assessment and meta-analysis were performed with The Cochrane Collaboration tool (RevMan 5.4). Quality of the evidence was assessed with GRADE tool. From the 3247 studies found, 19 were included. In the qualitative analysis, seven studies showed TENS, electroacupuncture, PTNS, and tDCS reduced pain intensity, one study on PTNS showed increased quality of life, and one on tDCS showed improved functional performance. However, in the meta-analysis, only TENS showed efficacy for the reduction of acute pelvic pain and primary dysmenorrhea. Our results indicate that there is moderate-quality evidence for TENS to reduce pain intensity in primary dysmenorrhea and low-quality evidence for the same outcome in acute pelvic pain. Randomized controlled clinical trials with larger sample size and with better methodological quality are needed to establish the effectiveness of other forms of electrical stimulation in pelvic pain.

A COMPARATIVE STUDY OF MANUAL TRACTION AND MECHANICAL TRACTION ON ACUTE DISCOGENIC PAIN

Background and purpose: Acute low back pain is defined as Low back pain that has been present for less than three months and it was estimated that 80% of the population suffers from low back pain (LBP) at some point of their lives. Low back pain is the primary factors which limit activity in patients less than 45 years old and it is of significant socio-economic relevance because it may lead to temporary loss of productivity, enormous medical and indirect costs or even leads to permanent disability. The purpose of study was to compare a manual traction versus mechanical traction for reduce acute discogenic pain. Method: The study was conducted at JKK Munirajah Medical Research Foundation college of physiotherapy Out Patient department 30 subjects were selected in random sampling method. They were divided into 2 Group, namely Group A and Group B with 15 subjects in each Group. The enrolled 30 subjects were randomly allotted to two Group A (15) &B (15).After recruitment on eligibility, informed consent is obtained on explaining the treatment to be given. Result: The result showed that there was statistical significant difference between Group A and B. The acute discogenic pain patient who was treated with manual traction had shown good improvement in reduction of acute discogenic pain. Conclusion: The study concluded that there was a statistically significant improvement in reduction of pain improving flexibility and functional ability after the treatment of manual traction for 4 weeks. Thus the study concluded that manual traction (MAT) was the effective treatment than mechanical traction (MET) of acute discogenic low back pain.

Celiac plexus block: A diagnostic tool for neurogenic median arcuate ligament syndrome.

The objective of this study was to evaluate the effect of outpatient celiac plexus block on acute pain reduction in patients with suspected median arcuate ligament syndrome. This is an Institutional Review Board approved, retrospective chart review. Data were collected and analyzed from patients who received celiac plexus blocks from November 1, 2021 through April 6, 2023. The primary outcome was pain reduction, determined by the change in numerical pain rating scale (NPRS) from pre-procedure to post-procedure. Additional data collected include patient demographics, comorbidities, preoperative symptoms and duration of symptoms. There were 33 patients identified in this study. Thirty-one patients were included in the data analysis. The median age of the cohort was 29 years, and the median BMI was 20.4. 94% of the cohort was female. These patients were referred as part of an evaluation for symptomatic vascular compression disorders. For many patients, positive response to celiac plexus block was used as an indication to proceed with surgical MALS resection. We provide a diagnostic algorithm for MALs. All patients endorsed preoperative symptoms. Patients experienced a median pain reduction of -4 from baseline to immediately post-procedure. Celiac plexus blocks continue to be a tool for ruling out neurogenic median arcuate ligament syndrome in patients who have undergone extensive previous imaging and assessments for vascular compression disorders. Our data suggest that patients with suspected MALS may experience substantial immediate pain relief from temporary blocks of the celiac ganglion as guided by fluoroscopy in an outpatient setting.

Neuromodulation treatments for migraine: a contemporary update.

Neuromodulation approaches have been a part of a revolution in migraine therapies with multiple devices approved or in development. These devices vary in the nerve(s) being targeted, implantable versus noninvasive form factors as well as their effectiveness for acute pain reduction or migraine prevention. This review will summarize these recent advancements and approaches that are being developed which build upon prior work and improved technology that may help enhance the effectiveness as well as the patient experience. Both noninvasive and implantable devices primarily targeting cranial nerves have shown the ability to help alleviate migraine symptoms. Multiple prospective and retrospective studies have demonstrated clinically meaningful reductions in headache intensity with noninvasive approaches, while prevention of migraine demonstrates more modest effects. Implantable neuromodulation technologies focusing on occipital and supraorbital stimulation have shown promise in migraine/headache prevention in chronic migraine patients, but there is a need for improvements in technology to address key needs for surgical approaches. Electrical neuromodulation approaches in the treatment of migraine is undergoing a transformation towards improved outcomes with better technologies that may suit various patient needs on a more individualized basis.

Anoctamin 1, a multi-modal player in pain and itch

Anoctamin 1 (ANO1/TMEM16A) encodes a Ca2+-activated Cl- channel. Among ANO1′s many physiological functions, it plays a significant role in mediating nociception and itch. ANO1 is activated by intracellular Ca2+ and depolarization. Additionally, ANO1 is activated by heat above 44 °C, suggesting heat as another activation stimulus. ANO1 is highly expressed in nociceptors, indicating a role in nociception. Conditional Ano1 ablation in dorsal root ganglion (DRG) neurons results in a reduction in acute thermal pain, as well as thermal and mechanical allodynia or hyperalgesia evoked by inflammation or nerve injury. Pharmacological interventions also lead to a reduction in nocifensive behaviors. ANO1 is functionally linked to the bradykinin receptor and TRPV1. Bradykinin stimulates ANO1 via IP3-mediated Ca2+ release from intracellular stores, whereas TRPV1 stimulates ANO1 via a combination of Ca2+ influx and release. Nerve injury causes upregulation of ANO1 expression in DRG neurons, which is blocked by ANO1 antagonists. Due to its role in nociception, strong and specific ANO1 antagonists have been developed. ANO1 is also expressed in pruritoceptors, mediating Mas-related G protein-coupled receptors (Mrgprs)-dependent itch. The activation of ANO1 leads to chloride efflux and depolarization due to high intracellular chloride concentrations, causing pain and itch. Thus, ANO1 could be a potential target for the development of new drugs treating pain and itch.

Progress in the treatment of Osteoarthritis with avocado-soybean unsaponifiable.

Osteoarthritis (OA) is one of the leading causes of joint dysfunction and disability in the elderly, posing serious social problems and a huge socio-economic burden. Existing pharmacological treatments have significant drawbacks, and searching for an effective pharmacological intervention is an urgent priority. Recent studies have demonstrated the chondroprotective, anabolic, and anti-catabolic properties of avocado-soybean unsaponifiable (ASU), a natural plant extract made from avocado and soybean oils, consisting of the remainder of the saponified portion of the product that cannot be made into soap. The main components of ASU are phytosterols, beta-sitosterol, canola stanols, and soya stanols, which are rapidly incorporated into cells. Studies have confirmed the anti-inflammatory, antioxidant, and analgesic properties of phytosterols. ASU slows down the progression of OA primarily by inhibiting pathways involved in the development of OA disease. ASU prevents cartilage degradation by inhibiting the release and activity of matrix metalloproteinases and by increasing the tissue inhibition of these catabolic enzymes; ASU is also involved in the inhibition of the activation of nuclear factor κB (NF-κB) which is a transcriptional inhibitor that regulates the inflammatory response of chondrocytes. NF-κB is a transcription factor that regulates the inflammatory response of chondrocytes, and inhibition of the transfer of the transcription factor NF-κB from the cytoplasm to the nucleus regulates the transcription of many pro-inflammatory factors. By appealing to the mechanism of action and thus achieving anti-inflammatory, anti-catabolic, and pro-synthetic effects on cartilage tissues, AUS is clinically responsive to the reduction of acute pain and OA symptom progression. This paper aims to summarize the studies on the use of avocado-soybean unsaponifiable in the pharmacological treatment of osteoarticular.

Fidelity to the acupuncture intervention protocol in the ACUpuncture In The EmergencY department for pain management (ACUITY) trial: Expanding the gold standard of STRICTA and CONSORT guidelines

BackgroundAcupuncture shows promise as an effective nonpharmacologic option for reduction of acute pain in the emergency department (ED). Following CONSORT and STRICTA guidelines, randomized controlled trials (RCTs) generally report intervention details and acupoint options, but fidelity to acupuncture interventions, critical to reliability in intervention research, is rarely reported. MethodsACUITY is an NCCIH-funded, multi-site feasibility RCT of acupuncture in 3 EDs (Cleveland, Nashville, and San Diego). ACUITY acupuncturists were trained in study design, responsive acupuncture manualization protocol, logistics and real-time recording of session details via REDCap forms created to track fidelity. ResultsAcross 3 recruiting sites, 79 participants received acupuncture: 51 % women, 43 % Black/African American, with heterogeneous acute pain sites at baseline: 32 % low back, 22 % extremity, 20 % abdominal, 10 % head. Pragmatically, participants were treated in ED common areas (52 %), private rooms (39 %), and semi-private rooms (9 %). Objective tracking found 98 % adherence to the six components of the acupuncture manualization protocol: staging, number of insertion points (M = 13.2, range 2–22), needle retention time (M = 23.5 min, range 4–52), session length (M = 40.3 min, range 20–66), whether general recommendations were provided and completion of the session form. ConclusionTo the best of our knowledge, this is the first RCT to assess and report fidelity to an acupuncture protocol. Fidelity monitoring will be fundamental for ACUITY2, which would be a future definitive, multi-site RCT. Furthermore, we recommend that fidelity to acupuncture interventions be added to CONSORT and STRICTA reporting guidelines in future RCTs. Protocol registrationThe protocol of this study is registered at clinicaltrials.gov: NCT04880733.

The Effectiveness of Hypnoanalgesia Using Conventional and Placebo Hypnosis Induction

The effectiveness of hypnosis-based pain management is well-established. However, mechanisms of action and specific effective components are not well understood. The sociocognitive theory of hypnosis proposes that the effectiveness of hypnosis for pain management is determined by the nonspecific features of response expectancy and context. We tested this claim by contrasting the effectiveness of 2 hypnoanalgesia procedures in a within subjects design using the cold pressor task. The 2 procedures were identical, including analgesic suggestions, except for the hypnosis induction used. One condition involved a well-established hypnosis induction, including suggestions for focused attention, relaxation, and deepening. The other condition included a sham induction procedure using only white noise. In our confirmatory analysis (N = 46), we found that pain tolerance increased compared to baseline equivalently in the conventional and sham induction conditions (mean increase 13.7 and 12.4 seconds respectively, average within subject difference −1.27 seconds, 90% confidence interval [CI] = −8.46, 5.90). This finding supports the claim of the sociocognitive theory considering that response expectancy for pain reduction was also equivalent between the conditions (average difference 2.30, 90% CI = −2.23, 6.84). However, self-reported hypnosis depth was greater in the conventional induction condition (average difference −.78, 90% CI: −1.36, −.07), which contradicts sociocognitive predictions. Our findings indicate that conventional procedural elements of hypnosis inductions, such as suggestions for focused attention, relaxation, and deepening, may not be necessary to achieve acute pain reduction in an experimental setting when the hypnosis intervention includes analgesic suggestions. PerspectiveThis study assessed the necessary effective components of hypnosis-based analgesia interventions. Our findings suggest that procedural features such as suggestions for focused attention, relaxation, and deepening may not be necessary for hypnoanalgesia as long as pain relief suggestions are present, and the hypnosis context and response expectancy are established. Trial registrationThis trial was registered on Open Science Framework with the registry number e96xk, available at https://osf.io/e96xk.

Abstract 7: Scrambler Therapy for Treatment of Post Stroke Pain

Objective: Infarcts involving sensory pathways can result in a post-stroke pain syndrome that is often refractory to traditional medical therapy. Scrambler Therapy (ST) is a noninvasive electroanalgesia device effectively used to treat peripheral neuropathy; however, data is scarce regarding its use in the central nervous system. In this pilot, we evaluate the efficacy of ST to treat post-stroke pain syndromes. Methods: Twenty patients with a history of stroke resulting in contralateral pain were enrolled and randomized to receive ST or Sham as an adjunct to their current medication regimen. Participants underwent 5 consecutive sessions, each lasting 40 minutes. Pain scores were recorded at baseline, as well as before and after each session using a Numeric Rating Scale (0-10). The study was double-blinded to both the participant and operator. Following treatment, pain scores were collected weekly for 4 weeks. Student’s t tests were used to compare scores at: baseline, immediately post-treatment #5, and at 4 week follow-up, between groups as well as the change in pain score between individuals. Results: To date, 15 patients have been enrolled and completed the intervention; 10 have completed longer-term follow-up. The average age of the cohort was 57.8 years; 47% were male; 53% black; and the average time from stroke was 26 months. Participants randomized to ST (n=7) had a mean pain score of 6.52 at baseline; the Sham group (n=8) had a mean score of 5.83. The ST group had a mean change from initial score to score after 5 days of treatment of -4.17 (SD 2.64), while the Sham group had a mean change in score of -1.03 (SD 1.42). For patients completing follow-up, the ST group (n=5) saw a mean change pain score from baseline to follow-up of -3.37 (SD 1.71). The Sham group (n=5) a mean change of -0.37 (SD 0.34). Differences in change in score were significant between groups at both time points (p=0.01 and 0.005 respectively). Conclusion: There is a significant difference in both acute and longer-term pain reduction for patients with post-stroke pain who undergo treatment using ST compared to Sham that suggests it may be an effective treatment option. Larger studies are needed to evaluate confounders such as stroke location, time from stroke, and concomitant treatment with medications.

Comparison of three regimens with inhalational methoxyflurane versus intranasal fentanyl versus intravenous morphine in pre-hospital acute pain management: study protocol for a randomized controlled trial (PreMeFen)

BackgroundPre-hospital pain management has traditionally been performed with intravenous (IV) morphine, but oligoanalgesia remain a recognized problem. Pain reduction is essential for patient satisfaction and is regarded as a measure of successful treatment. We aim to establish whether non-invasive methods such as inhalation of methoxyflurane is non-inferior to intranasal fentanyl or non-inferior to the well-known IV morphine in the pre-hospital treatment of acute pain.Method/designThe PreMeFen study is a phase three, three-armed, randomized, controlled, non-inferiority trial to compare three regimens of analgesics: inhalation of methoxyflurane and intranasal (IN) fentanyl versus IV morphine. It is an open-label trial with a 1:1:1 randomization to the three treatment groups. The primary endpoint is the change in pain numeric rating scale (NRS) (0–10) from baseline to 10 min after start of investigational medicinal product administration (IMP). The non-inferiority margin was set to 1.3, and a sample size of 270 patients per protocol (90 in each treatment arm) will detect this difference with 90% power.DiscussionWe chose a study design with comparison of analgesic regimens rather than fixed doses because of the substantial differences in drug characteristics and for the results to be relevant to inform policymakers in the pre-hospital setting. We recognize that easier administration of analgesics will lead to better pain management for many patients if the regimens are as good as the existing, and hence, we chose a non-inferiority design. The primary endpoint, the change in pain (NRS) after 10 min, is set to address the immediate need of pain reduction for patients with acute prehospital pain. On a later stage, more analgesic methods are often available.SummaryPreMeFen is a non-inferiority randomized controlled trial comparing three analgesic regimens aiming to establish whether inhalation of methoxyflurane or intranasal fentanyl is as good as IV morphine for fast reduction of acute pain in the prehospital setting.

Comparison of the Effect of Injectable Acetaminophen with Injectable Ketamine by Morphine Pump on Reducing Acute Pain after Laparoscopic Cholecystectomy Surgery

Introduction: At the issues that have always been the concern of the surgical team is finding a way to better control post-operative pain, because pain controls a significant role in the length of time the patients stay in the hospital, the level of patient satisfaction, the recovery period and the patient's return to normal life activities. Millions of patients in the world undergo surgery every year, and most of them report unrelieved pain after the surgery. Aim: To compare the control and reduction of acute pain in patients after laparoscopic gallbladder surgery by injectable acetaminophen and injectable ketamine. Materials and methods: this RCT study, which was conducted as a non-blind randomized clinical trial, 50 laparoscopic gallbladder surgery patients who referred to the teaching hospitals of Qazvin University of Medical Sciences in 2022 were selected as available and as Injectable acetaminophen and injectable ketamine were randomly divided into two drug groups and pain reduction was investigated and analyzed. Results: this study, the average age group of patients (in two groups) was 49.34 ± 13.52, and the pain reduction in both groups was less in those under 30 years of age, and more pain reduction in those over 30 years old, so that over 50 years of age had the greatest pain reduction, and The reduction of pain in the acetaminophen group was more than that of ketamine and it was statistically significant (P = 0.02). The reduction in pain intensity in the patients in the injectable acetaminophen drug group after receiving the full dose of the drug showed a noticeable and greater decrease compared to the ketamine group. Therefore, injectable acetaminophen was seen as an effective drug in reducing pain after laparoscopic surgery and it was statistically significant. (P = 0.002). Conclusion: In this study, the effect of injectable acetaminophen was very effective in reducing the amount of pain and the intensity of pain after laparoscopic surgery, but ketamine not only does not reduce the effect of pain, but it also changes the effect of other.

A service evaluation of the newly introduced sciatic nerve local anaesthetic infusion catheters for acute pain management of major lower limb amputations

Background: Patients who undergo lower limb amputations experience severe acute postoperative pain. Despite having no strong evidence for the efficacy of peripheral nerve blocks in reducing phantom limb pain, the reduction in acute postoperative pain and opioid-sparing effect1 make these techniques important to consider. Acute pain management has been identified as a key priority in the management of patients undergoing amputation.2 An initial audit, in October 2021, found that postoperative pain scores and opiate use were high. In April 2022, postoperative local anaesthetic nerve catheters for major lower limb amputations were introduced at our institution. The aim of this service evaluation was to ascertain the postoperative pain scores and analgesic consumption for patients having undergone a lower limb amputation and who subsequently received a continuous postoperative local anaesthetic infusion (levobupivacaine 0.125%, at 6–10 ml h−1 for up to 5 days) via a sciatic nerve catheter. Methods: A retrospective audit was undertaken between July and September 2022 at Birmingham Heartlands Hospital. We included patients having undergone a lower limb amputation with a sciatic nerve catheter placed intraoperatively by surgeons under direct vision and left along the nerve in the cut nerve sheath. Data collected included patient characteristics, postoperative pain scores days 1–5, postoperative opioid use including opioid side-effects, postoperative neuropathic pain, and block related complications. Results: We collected data for 24 patients. Compared with the period before the introduction of sciatic nerve catheters, we observed that the mean pain scores on the numeric rating scale (NRS) decreased. This was particularly evident on day 1 postoperatively when the mean pain scores decreased from the moderate to mild range. On days 1–5 of the postoperative period, the mean immediate-release opioid consumption was 16.1 mg day−1 and mean prolonged-release opioid consumption was 11.6 mg day−1. This was in comparison to the audit in October 2021 that found mean opioid use of 24.1 mg day−1 and 21 mg day−1, respectively. Opioid side-effects reported were sedation (18%), constipation (13%), and nausea or vomiting (8%). Fifty percent of patients reported neuropathic pain. Conclusion: The postoperative pain scores improved and the postoperative opioid consumption reduced slightly with the addition of a sciatic nerve catheter. Opioid side-effects and acute neuropathic pain remain an issue for this group of patients postoperatively. Overall, the introduction of a continuous local anaesthetic infusion via a sciatic nerve catheter after major lower limb amputations in our hospital has been a success and the technique is likely to play a significant future role as part of our multi-modal analgesia regimen for these patients. The Acute Pain Team at University Hospitals Birmingham NHS Foundation Trust. 1.Ilfeld BM. Anesth Analg 2011; 113: 904–252.Gough MJ, Juniper M, Freeth H, Butt A, Mason M. Lower limb amputation: Working together. A report by the National Confidential Enquiry into Patient Outcome and Death, 2014. https://www.hqip.org.uk/wp-content/uploads/2018/02/lower-limb-amputation-report.pdf (accessed 20/03/23)

Virtual Reality & Acute Pain: A Literature Review

IssueSafe and effective pain management is a challenge among hospitalized patients. Pharmacological interventions are often the first choice but are associated with side effects and can contribute to the opioid epidemic. Nonpharmacological interventions, such as virtual reality (VR), may be an effective adjuvant in pain reduction. This literature review addressed the following question: Does VR compared to standard treatment reduce pain in hospitalized adult patients? DescriptionThis systematic search and limited review of the research literature was conducted using the Medline Complete Database. Keywords used included virtual reality, acute pain, and pain management. Results included three systematic reviews, one randomized controlled trial, and one cohort study. Results: Key findings from all five articles indicate that VR is an effective non-pharmacological therapy in acute pain reduction. The articles show that VR can be a complementary intervention to some pharmacological analgesia, highlighting its potential application as an adjunct in multimodal pain management. Conclusions and RecommendationsBased on key findings, VR is a safe, effective, drug-free solution for pain management in hospitalized adult patients. Offering VR as a treatment modality to patients experiencing acute pain in the inpatient setting can help reduce their reported pain level. Recommendations for practice may include incorporating VR as a non-pharmacological therapy in a multimodal pain management strategy. Suggestions include offering VR to patients before initiating pharmacological therapy and reducing the dosage and frequency of opioid administration. Future research can include measuring the reduction in opioid intake when used in conjunction with VR, calculating the amount of VR exposure time that is necessary to make a significant difference in patient-reported pain level, and experimenting with different visualizations offered by VR to see its impact on pain reduction.

Pain assessment after anterior cruciate ligament reconstruction with autograft: quadrupled m.semitendinosus versus m.semitendinosusand m.gracilis

Anteriorcruciate ligament (ACL) tear is one of the most common sports injuries. The all-inside technique (AIT) for anterior cruciate ligament reconstruction (ACLR) is gaining popularity as a more anatomic, less invasive technique with the potential for more rapid recovery. With the recent advances in the field of sports medicine, the all-inside technique is reported to have less postoperative pain as compared to the conventional transportable procedure. The purpose of this research is to determine the differences in acute pain levels between undergoing ACL reconstruction hamstring autograft m. semitendinosusand m.gracilis versus hamstring autograft quadrupled m.semitendinosus in first and second postoperative day. Materials and Methods: A total of 80 patients in period of two years who underwent primary ACL reconstruction using either HS autograft m.semitendinosusand m.gracilis or HS autograft quadrupled m.semitendinosus consented to participate. The primary outcome of the study was postoperative pain levels that were collected after surgery at first and second day. For the quantification of the intensity of pain after the surgery the patients were offered a Visual Analogue Scale (VAS scale), numbered from 0 to 10 (0 means no pain, 10 is the strongest pain). This part of the research shows the results obtained by processing patients with ACL, treated at the Department of Orthopaedics and Traumatology in the City General Hospital "8th of September" in Skopje. Results: The average postoperative score one day after surgery for patients with a standard method using a graft in the form of a duplication of m.semitendinosus and m.gracilis based on the VAS scale was 7.70 +0.9 and the score second day after surgery was 4.75 + 1.1.The average postoperative score a day after the surgery for patients treated with the method where only m.semitendinosus is used as a graft and that in the form of quadruplicationbased on the VAS scale was 3.90 +3.1and the score second day after surgery was 2.70 +2.7. Conclusion: A significant reduction in acute postoperative pain was found when performing ACL reconstruction with HS quadrupledm.semitendinosus compared to HS m.semitendinosus-m.gracilis.

Robotic-assisted esophagectomy leads to significant reduction in postoperative acute pain: A retrospective clinical trial

Robotic-assisted esophagectomy leads to significant reduction in postoperative acute pain: A retrospective clinical trial

Low-load resistance exercise completed to volitional failure decreases pain perception post-exercise in females and males

Exercise-induced hypoalgesia (EIH) is the acute pain reduction post-exercise. Typically, high-intensity and/or long-duration exercise is required to elicit EIH. Alternatively, low-load resistance exercise with blood flow restriction (LL+BFR) may elicit EIH. However, there is conflicting evidence regarding the necessary repetitions and volume load. This study evaluated EIH after 75-repetitions (1×30, 3×15) (BFR-75) and four sets to volitional failure (BFR-F) protocols. Twenty-six participants completed unilateral knee extensions at 30% of maximal strength using a BFR-75 and BFR-F protocol. Pain pressure threshold (PPT) of the rectus femoris was assessed before and after exercise. Repetitions completed, volume load, occlusion time, and PPT were analyzed. Participants completed more repetitions (91.4±30.5), volume load (5,204.9±2,367.0 Nm), and had a longer occlusion time (345.8±76.2 seconds) during BFR-F compared to BFR-75 (73.2±3.7 repetitions, 4,451.1±1,498.1 Nm, 300.5±52.2 seconds, respectively). Collapsed across sex, PPT increased from pre- (3.24±1.91 kgf) to post-exercise (3.76±2.27 kgf) for BFR-F but not BFR-75 (3.51±1.67 to 3.68±2.04 kgf). The results indicated that BFR-F, but not BFR-75, elicited EIH, as assessed by an increase in PPT. Lower loads used during LL+BFR may be a clinically relevant alternative to high-intensity and/or long-duration exercise in populations that may not tolerate high-intensity or prolonged exercise to induce EIH.

Efficacy of Cannabidiol Versus Ibuprofen in the Relief of Menstrual Pain in Females Living with Primary Dysmenorrhea A phase II, Non-Inferiority trial

Introduction: Pain is the cardinal symptom in women living with primary dysmenorrhea (PDM), resulting in a relentless negative effect on their quality of life.  Women with PDM have higher levels of prostaglandin in their endometrial fluid, which correlates with the degree of pain. The standard of care treatment for pain associated with PDM starts with nonsteroidal anti-inflammatory drugs (NSAIDs) that block prostaglandin-triggering enzymes. Although NSAIDs present as a feasible option, they are also associated with a significant risk of side effects. Around 20 to 25% of patients will experience pain refractory to NSAIDs and will then seek alternative therapies. Cannabidiol (CBD) is a well-tolerated potential therapy for several chronic diseases, including pain, and acts by blocking prostaglandin-triggering enzymes, similarly to NSAIDs. The safety of CBD is well established, with the advantage of it acting via central and peripheral mechanisms. To date, no previous trials assessing CBD alone for dysmenorrhea have been conducted. Objective: To evaluate the effect of CBD alone in the reduction of acute menstrual pain compared to ibuprofen, as assessed by the total pain relief (TOTPAR) scale. Design: Randomized (with random block sizes), triple-blinded, multicenter, parallel-group, non-inferiority clinical trial. Setting: St. George, Scarborough, and Mississauga campuses at the University of Toronto, Ontario, Canada. Participants: PDM patients aged 18 to 40 years, regular menstrual cycles (ranging from 21 to 35 days), and a visual analog scale (VAS) score of ≥ 5. Intervention: 108 patients will be randomized with an allocation ratio of 1:1 to either CBD 200 mg/day or ibuprofen 800mg/day. The sample size is based on a mean expected pain relief for ibuprofen of 16.49 and CBD of 14.02, as assessed by the TOTPAR scale and on a 30% estimated dropout rate. Main Outcome Measures: The primary outcome will be the mean difference in the TOTPAR scale (range, 0-4) after taking the study drugs over four menstrual cycles. TOTPAR will be assessed after 1, 2, 3, 4, 5, and 6 hours after taking the study drugs. Secondary outcomes include pain VAS, adverse events, the need for breakthrough medications, and quality of life (QoL). Discussion: NSAIDs may cause troubling side effects, and CBD is well tolerated in clinical trials, with acceptable adverse event profiles. Numerous randomized clinical trials have demonstrated the safety and efficacy of CBD in alleviating central and peripheral pain of other disorders. The results of this trial aim to provide much-needed evidence that oral CBD alone is an alternative for the treatment of menstrual pain in women with PDM. CBD presents as an important promise for women with PDM who do not respond or who have contraindications to NSAIDs. Keywords: Cannabidiol, CBD, menstrual pain, ibuprofen, pain relief, non-inferiority, dysmenorrhea

Use of Diphenhydramine for Pain Management in the Emergency Department: A Systematic Review and Meta-analysis

BACKGROUND Diphenhydramine, commonly prescribed as an antihistamine drug, is not known for its analgesic effect and its use in acute pain management has not been thoroughly investigated. AIM In this study, we aim to explore the analgesic properties of diphenhydramine and its role in acute pain reduction in the emergency department (ED). METHODS A systematic review and meta-analysis were performed. The inclusion criteria were randomised controlled trials that investigated the effect of intravenous diphenhydramine on the management of acute pain. Acute pain reduction was defined as a reduction in the visual pain score within one hour of drug administration. We excluded non-English articles, articles that measured the impact of diphenhydramine beyond the acute period, and those that used a pain score other than the 10-point visual pain scale. The information sources included PubMed, Google Scholar, Cochrane, PROSPERO, and grey literature (ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform) databases for articles published between 1963 and January 2022, along with the articles referenced at the end of the reviews, for the keywords ‘diphenhydramine’, ‘antihistamine’, ‘pain’, and ‘analgesia’. The researchers used the RoB 2 Cochrane risk-of-bias tools for randomised controlled trials. RESULTS We included four studies out of 128,902 involving 438 patients, out of whom 218 received diphenhydramine for pain control. The mean pain score in patients who received diphenhydramine was reduced by 28%; t(6)= -2.879, 95% CI [-2.87 to -0.23], p=0.028. When the baseline pain score was included in the analysis, we noted a reduction of 48% from the initial pain score. The pooled effect size or mean difference in acute pain reduction favouring diphenhydramine, taken from a random-effects model, was -1.53 (95% CI: [-2.35 to -0.70]) using Cohen’s d. CONCLUSION This meta-analysis confirms the analgesic advantages of diphenhydramine and supports its consideration as an adjunct for acute pain management in the ED.

Reduction of Acute Postoperative Pain With Pre-Emptive Pregabalin Following Laparoscopic Cholecystectomy

Pregabalin has been considered to be a safe treatment for neuropathic pain. Owing to the lack of research regarding the use of pregabalin in the management of pain in under-resourced settings, our study aimed to deduce the effectiveness of a pre-emptive single dose of pregabalin pre-operatively to provide pain relief after laparoscopic cholecystectomy. Treating acute pain is essential to avoid an increased hospital stay. There is a need for non-opioid drugs with lower risks to avoid using opioids, which lead to many side effects.MethodologyPatients diagnosed with cholelithiasis and scheduled to undergo laparoscopic cholecystectomy at the Abbasi Shaheed Hospital were included in this study. The study aimed to determine whether the effect of pregabalin in combination with patient-controlled analgesia can decrease pain scores. This was a double-blind study where patients, caregivers, and analysts were blinded to group allocation and drugs administered until the data was recorded and sealed. The patients were divided into pregabalin and placebo groups through a web-based model; blocks of four were used and stratification was employed at the center. A confidence interval of 95% was considered significant.ResultsIn our study, a total number of 60 patients were included. They were randomly divided by a computer-based model into two groups, the pregabalin group, and the control group. The placebo group had 33 patients while the pregabalin group had 27 patients. The pregabalin group was given a pregabalin tablet of 150 mg before surgery while the placebo group was given an identical-looking placebo. Patient-controlled analgesia was started in both groups and the visual analog scale (VAS) scoring was observed postoperatively. The pregabalin group had a decreased incidence of pain as compared to the placebo group. There were no significant side effects during the trial; episodes of vomiting were managed using intravenous ondansetron.ConclusionPregabalin is effective in reducing pain in an acute postoperative period when compared with a placebo. Patients who were pre-emptively administered pregabalin reported decreased VAS as compared to the placebo. However, both were inefficient in reducing postoperative nausea and vomiting.

Robotic-Assisted Esophagectomy Leads to Significant Reduction in Postoperative Acute Pain: A Retrospective Clinical Trial

BackgroundRobot-assisted minimally invasive esophagectomy (RAMIE) shows promising results regarding postoperative complications in patients with esophageal cancer. To date, no data are available regarding postoperative analgesic consumption. The aim of this work is to evaluate analgesic consumption after esophagectomy.MethodsA total of 274 Ivor Lewis esophageal resections performed sequentially from January 2012 to December 2020 were evaluated. RAMIE cases (n = 51) were compared with the hybrid technique (laparoscopic abdominal phase followed by open thoracotomy, n = 59) and open abdominothoracic esophagectomy (OTE) (n = 164). Data were collected retrospectively. The primary endpoint was the overall postoperative morphine consumption, which represents a reliable indirect measurement of pain. Pain levels recorded on the first, third, and fifth postoperative days were assessed as secondary endpoints.ResultsA total of 274 patients were included. The postoperative opioid consumption rate for patients who underwent RAMIE (quartiles: 0.14, 0.23, 0.36 mg morphine milligram equivalents (MME)/kg body weight (bw)/day) was significantly lower than in the open group (0.19, 0.33, 0.58 mg MME/kg bw/day, p = 0.016). The overall postoperative opioid consumption for patients who underwent RAMIE was significantly lower (2.45, 3.63, 7.20 mg MME/kg bw/day; morphine milligram equivalents per kilogram body weight) compared with the open (4.85, 8.59, 14.63 MME/kg bw/day, p < 0.0001) and hybrid (4.13, 6.84, 11.36 MME/kg bw/day, p = 0.008) groups. Patients who underwent RAMIE reported lower pain scores compared with the open group on the fifth postoperative day, both at rest (p = 0.004) and while performing activities (p < 0.001).ConclusionsThis study shows that patients who underwent RAMIE experienced similar postoperative pain while requiring significantly lower amounts of opioids compared with patients who underwent open and hybrid surgery. Further studies are required to verify the results.