Prediction of postoperative pain after gynecologic laparoscopy for nonacute pelvic pain

Guideline No. 445: Management of Chronic Pelvic Pain

OBJECTIVE

To provide evidence-based recommendations for the management of chronic pelvic pain in females.

TARGET POPULATION

This guideline is specific to pelvic pain in adolescent and adult females and excluded literature that looked at pelvic pain in males. It also did not address genital pain.

BENEFITS, HARMS, AND COSTS

The intent is to benefit patients with chronic pelvic pain by providing an evidence-based approach to management. Access to certain interventions such as physiotherapy and psychological treatments, and to interdisciplinary care overall, may be limited by costs and service availability.

EVIDENCE

Medline and the Cochrane Database from 1990 to 2020 were searched for articles in English on subjects related to chronic pelvic pain, including diagnosis, overlapping pain conditions, central sensitization, management, medications, surgery, physiotherapy, psychological therapies, alternative and complementary therapies, and multidisciplinary and interdisciplinary care. The committee reviewed the literature and available data and used a consensus approach to develop recommendations. Only articles in English and pertaining to female subjects were included.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

Family physicians, gynaecologists, urologists, pain specialists, physiotherapists, and mental health professionals.

TWEETABLE ABSTRACT

Management of chronic pelvic pain should consider multifactorial contributors, including underlying central sensitization/nociplastic pain, and employ an interdisciplinary biopsychosocial approach that includes pain education, physiotherapy, and psychological & medical treatments.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Trajectory of pain threshold and its association with acute pain after thoracic surgery: a prospective observational study

BACKGROUND

Postoperative analgesic management is an ongoing challenge. The pain threshold (PT) is an objective index that reflects the body's sensitivity to pain and can be used for quantitative pain assessment. We hypothesized that the PT is correlated with postoperative pain and can thus be used to guide postoperative pain management.

METHODS

This study involved 93 patients who underwent thoracoscopic surgery from December 2019 to February 2020. The PT was measured with transcutaneous electrical stimulation before surgery (T0) and at 1 h (T1), 6 h (T6), and 24 h (T24) after surgery. The visual analogue scale (VAS) score was used to evaluate the severity of postoperative pain at the same time. The PT variation (PTV) after surgery was calculated as the ratio of the postoperative PT to preoperative PT.

RESULTS

The postoperative PT was higher than the preoperative PT and showed a downward trend within 24 h after surgery; the PTV also showed a downward trend within 24 h after surgery. PT-T1 was negatively correlated with VAS-T1 at rest and during motion (rest: VAS-T1r = - 0.274, P = 0.008; motion: VAS-T1r = - 0.298, P = 0.004). PTV-T1 was negatively correlated with VAS-T1 during motion (r = - 0.213, P = 0.04). Lower VAS-T1 scores (< 4) at rest and during motion were associated with higher PT-T1 (rest: t = 2.452, P = 0.016; motion: t = 2.138, P = 0.035). The intraoperative sufentanil dose was associated with a postoperative increase in PTV-T1. Increased rescue analgesic administration was associated with PTV elevation. However, the incidence of dizziness in patients with moderate PTV-T24 was lower than that in patients with high or low PTV-T24 (χ2 = 8.297, P = 0.015).

CONCLUSIONS

The postoperative PT was higher than the preoperative PT and showed a downward trend within 24 h after surgery; PTV also showed a downward trend within 24 h after surgery. The PT and PTV were negatively correlated with the pain intensity at rest and during motion and were associated with perioperative analgesic consumption and the incidence of adverse events.

The role of catastrophizing in chronic cyclical pelvic pain: A systematic review and meta-analysis

BACKGROUND

Dysmenorrhea (painful menstrual cramps) is one of the most common gynecological complaints in women and girls. Dysmenorrhea may be a condition itself or a result of another medical condition, including endometriosis and chronic pelvic pain. Research examining the relationship between menstrual pain ratings and catastrophizing has produced mixed results.

OBJECTIVE

To review and meta-analyze the relationship between catastrophizing and pain ratings of chronic cyclical pelvic pain.

DESIGN

Cross-sectional, longitudinal, and intervention studies that reported the relationship between menstrual/pelvic pain and catastrophizing were included. Study populations had to include healthy menstruating persons or persons with a condition associated with cyclical pelvic pain including primary dysmenorrhea, endometriosis, and/or chronic pelvic pain.

DATA SOURCES AND METHODS

A systematic search of articles published since 2012 on PubMed, PsychInfo, CINHAL, and Medline was conducted in January and rerun in November of 2022. Search terms included cyclical pelvic pain, dysmenorrhea, endometriosis, pelvic pain, and catastrophizing. Data extraction was completed independently by two extractors and cross-checked for errors. A random-effects meta-regression was used to synthesize the data using restricted maximum likelihood.

RESULTS

Twenty-five studies examining 4,540 participants were included. A random effects model found a meta-correlation between catastrophizing and pain of r = .31 (95% confidence interval: .23-.40) p < .001. Heterogeneity was large and significant (I2 = 84.5%, Q(24) = 155.16, p < .001). Studies that measured general pelvic pain rather than cyclical pelvic pain specifically and those that used multi-item rather than single-item measures of pain had significantly higher correlations. Age and depression did not moderate the relationship between catastrophizing and pain.

CONCLUSION

A systematic review and meta-analysis found that catastrophizing had a small but significant positive association with pain ratings. Patients experiencing cyclical pelvic pain may benefit from interventions targeting the psychological management of pain.

REGISTRATION

This meta-analysis was registered in PROSPERO on 14 January 2022. Registration number: CRD42022295328.

Virtual reality and its use in post-operative pain following laparoscopy: a feasibility study

Pain following laparoscopic surgery remains a neglected healthcare issue. Virtual reality-mediated therapy’s (VRT) analgesic potential could address this. However, its effect in this setting remains unexplored. We aimed to establish the feasibility and safety of VRT as an adjunct analgesic following gynaecological laparoscopy and explore differences between active distraction and passive meditation content. 35 women were enrolled into an open crossover pilot and randomised to either intervention group 1 (active then passive content) or intervention group 2 (passive then active content) following surgery. VRT was administered in two 10-min segments with a 10-min washout period in between. Pain scores, opioid requirements and side effects were recorded before and after each segment whilst questionnaires evaluated acceptability. We observed a significant reduction in pain over time for the entire study population (F = 8.63, p < 0.0005) but no differences between intervention groups, in contrast to many studies demonstrating an increase in pain during this time. During segment one, intervention group 1 (n = 18) were administered significantly less opioid than intervention group 2 (n = 17) [0.0 (0.0–7.5) vs. 3.0(0.0–10.0), p = 0.04]. Intervention group 1 rated the VRT experience significantly higher than intervention group 2 (7.97 vs. 6.62. p = 0.017). 97.1% (n = 34) would recommend VRT to a friend and use it as the standard-of-care in future procedures. These results demonstrate that post-operative VRT is feasible and safe. However, adequately powered studies are needed to appropriately determine its efficacy.

Emergency treatment in gynecology using different methods of surgery

The aim. Improving surgical treatment of urgent genital pathology based on comparing the effectiveness of different methods of surgery. Materials and methods. 170 women were selected and divided into three groups. Group 1 included women with acute pelvic inflammatory disease (aPID); to 2nd group – 60 women with intra-abdominal bleeding (IAB); to 3rd group - 50 women with impaired blood supply to tumors of the internal genitalia (uterus and ovaries) (IBSTIG). Each group was divided into two equivalent subgroups depending on the method of treatment: laparoscopic or laparotomy. During the study, all examined patients had a medical history, gynecological examination, ultrasound examination, surgical treatment by laparoscopy or laparotomy. Results. The average duration of laparoscopic operations in patients in subgroup 1.1 was 50.4±7.2 minutes and 80.3±10.1 minutes in subgroup 1.2 – with laparotomy method. Intraoperative blood loss was significantly lower in subgroup 1.1 compared with subgroup 1.2 (210.7±31.4 ml and 375.9±44.5 ml) (p <0.01). In the postoperative period in subgroup 1.1, which included women with emergencies due to aPID and in which operations were performed laparoscopically, the maximum temperature rise after surgery was 37.6±0.04 °C, which was significantly lower than in subgroup 1.2, which included women with emergencies due to aPID and in which operations were performed by laparotomy, this figure was 38.0±0.08 °C (p <0.001). The mean duration of the postoperative period in patients of subgroup 1.1 was significantly shorter compared to subgroup 1.2 (7.2±0.6 and 10.2±1.0 days) (p <0.05). The average duration of operations in subgroup 2.1 was significantly shorter than in subgroup 2.1 (39.8±2.1 and 59.1±2.5 minutes, respectively) (p <0.001). Intraoperative blood loss was on average significantly lower in subgroup 2.1 (189.1±19.8 and 388.5±37.2 ml, respectively) (p <0.05). In subgroup 3.1, which included women with IBSTIG and underwent surgical treatment by laparoscopy, the average duration of operations was significantly shorter than in subgroup 3.2, where such women with such pathology received surgical treatment by laparotomy (62.1±4.9 and 89.6±7.8 minutes, respectively) (p <0.01). Blood loss was significantly lower in subgroup 3.1 in contrast to subgroup 3.2 (101.7±10.1 ml and 283.3±12.9 ml, respectively) (p <0.001). Conclusions. The use of laparoscopy for the treatment of urgent genital pathology could increase the effectiveness of surgical treatment. In addition, this method reduces the duration of surgery and surgical blood loss. As a result, it makes it possible to improve the postoperative period.

The impact of preoperative pelvic pain on outcomes after vaginal reconstructive surgery

BACKGROUND

Pelvic pain is a debilitating condition that is common among women with pelvic floor disorders. Limited information is known about the impact of preoperative pelvic pain on outcomes after vaginal reconstructive surgery.

OBJECTIVE

This study aimed to compare the outcomes after vaginal reconstructive surgery between women with and without preoperative pelvic pain.

STUDY DESIGN

Baseline and postoperative data were analyzed from the "Outcomes Following Vaginal Prolapse Repair and Midurethral Sling trial." The multicenter trial involved women with anterior prolapse without symptoms of stress incontinence randomized to receive either a midurethral sling or sham incisions during a vaginal reconstructive surgery. Participants completed the visual analog scale adapted for suprapubic pain and Pelvic Floor Distress Inventory at baseline, 3 months, and 12 months. Preoperative pelvic pain was defined as a response of "5" or greater on pain on the visual analog scale or answering "moderately" or "quite a bit" on the Pelvic Floor Distress Inventory question, "Do you usually experience pain in the lower abdomen or genital area?" Outcomes and complication rates were compared between women with and without pelvic pain.

RESULTS

The "Outcomes Following Vaginal Prolapse Repair and Midurethral Sling trial" participants included 112 women with pelvic pain (58 had a midurethral sling and 54 had sham incisions) and 212 women without pelvic pain (105 had a midurethral sling and 107 had sham incisions). Women who had a midurethral sling and pelvic pain were younger than women without pelvic pain (60.3±12.1 vs 65.1±8.6; P=.004). Women who had sham incisions and pelvic pain were more likely of Hispanic ethnicity than women without pelvic pain (27.8% vs 9.4%; P=.002). Patient improvement based on the Patient Global Impression of Improvement scale did not differ between arms. Women with pelvic pain had greater improvement on the visual analog scale pain scores after a surgical procedure at 3 months (-3.1±2.9 vs -0.4±1.6; P<.001) and at 12 months (-3.4±3.0 vs -0.6±1.6; P<.001) than women without pain, although their pain scores remained higher than those without preoperative pelvic pain at all time points (P<.001 for all). Similar improvements were found on the Pelvic Floor Distress Inventory and Pelvic Floor Impact Questionnaire. The differences observed were not affected by whether women were in the midurethral sling or sham arm of the trial. Postoperative urinary tract infection and incomplete bladder emptying did not differ between the groups.

CONCLUSION

Women with preoperative pelvic pain experienced significant improvements in pain and pelvic floor symptoms with vaginal reconstructive surgery and had similar subjective improvement postoperatively compared with women without preoperative pelvic pain. Reassuringly, the performance of a midurethral sling did not have an impact on the results.

Identification of preoperative predictors for acute postsurgical pain and for pain at three months after surgery: a prospective observational study

Identifying patients at risk is the start of adequate perioperative pain management. We aimed to identify preoperative predictors for acute postsurgical pain (APSP) and for pain at 3 months after surgery to develop prediction models. In a prospective observational study, we collected preoperative predictors and the movement-evoked numerical rating scale (NRS-MEP) of postoperative pain at day 1, 2, 3, 7, week 1, 6 and 3 months after surgery from patients with a range of surgical procedures. Regression analyses of data of 2258 surgical in- and outpatients showed that independent predictors for APSP using the mean NRS-MEP over the first three days after surgery were hospital admittance, female sex, higher preoperative pain, younger age, pain catastrophizing, anxiety, higher score on functional disability, highest categories of expected pain, medical specialty, unknown wound size, and wound size > 10 cm compared to wound size ≤ 10 cm (RMSE = 2.11). For pain at three months, the only predictors were preoperative pain and a higher score on functional disability (RMSE = 1.69). Adding pain trajectories improved the prediction of pain at three months (RMSE = 1.37). Our clinically applicable prediction models can be used preoperatively to identify patients at risk, as well as in the direct postoperative period.

The predictive value of quantitative sensory testing: a systematic review on chronic postoperative pain and the analgesic effect of pharmacological therapies in patients with chronic pain

Studies have suggested that quantitative sensory testing (QST) might hold a predictive value for the development of chronic postoperative pain and the response to pharmacological interventions. This review systematically summarizes the current evidence on the predictive value of QST for chronic postoperative pain and the effect of pharmacological interventions. The main outcome measures were posttreatment pain intensity, pain relief, presence of moderate-to-severe postoperative pain, responders of 30% and 50% pain relief, or validated questionnaires on pain and disability. A systematic search of MEDLINE and EMBASE yielded 25 studies on surgical interventions and 11 on pharmacological interventions. Seventeen surgical and 11 pharmacological studies reported an association between preoperative or pretreatment QST and chronic postoperative pain or analgesic effect. The most commonly assessed QST modalities were pressure stimuli (17 studies), temporal summation of pain (TSP, 14 studies), and conditioned pain modulation (CPM, 16 studies). Of those, the dynamic QST parameters TSP (50%) and CPM (44%) were most frequently associated with chronic postoperative pain and analgesic effects. A large heterogeneity in methods for assessing TSP (n = 4) and CPM (n = 7) was found. Overall, most studies demonstrated low-to-moderate levels of risk of bias in study design, attrition, prognostic factors, outcome, and statistical analyses. This systematic review demonstrates that TSP and CPM show the most consistent predictive values for chronic postoperative pain and analgesic effect, but the heterogeneous methodologies reduce the generalizability and hence call for methodological guidelines.

Preoperative Pressure Pain Threshold Is Associated With Postoperative Pain in Short-Stay Anorectal Surgery: A Prospective Observational Study

BACKGROUND:

Postoperative pain management is key for patient satisfaction. Pressure pain threshold (PPT) has been studied in some surgical cohorts but has not been studied in relationship to acute postoperative pain in short-stay patients undergoing anorectal surgery. We hypothesized that preoperative finger PPT measurements can identify respective patients with higher postoperative pain. Aiming to understand the relationship with subjective postoperative pain perception, we tested the hypotheses that preoperative PPT is associated with postoperative Visual Analog Scale (VAS) pain scores and correlates with postoperative analgesic consumption in short-stay patients undergoing anorectal surgery.

METHODS:

We prospectively assessed preoperative PPT in a cohort undergoing anorectal surgery, known as a moderately to severely painful procedure. Linear mixed-effects models were used to assess the relationship with postoperative VAS pain scores at 1 and 3 days as well as 4 weeks postoperatively. Logistic regression was used to study the relationship with additional postoperative analgesic consumption.

RESULTS:

We studied 128 patients and found that preoperative PPT is significantly associated with postoperative pain (P value for interaction = .025). Logistic regression modeling additionally revealed an association between the preoperative PPT and the need for additional postoperative analgesics, with odds of requiring additional analgesia decreasing by about 10% for each 1-point increase in PPT (odds ratio [OR] = 0.90; 95% confidence interval [CI], 00.81–0.98; P = .012).

CONCLUSIONS:

Preoperative finger PPT is associated with postoperative pain and might help identify patients who are at risk of developing more severe postoperative pain on anorectal surgery. Especially in ambulatory and short-stay settings, this approach can help to address patients’ high variability in pain sensitivity to facilitate appropriate postoperative analgesia, timely discharge, and prevent readmission.

Patient phenotyping in clinical trials of chronic pain treatments: IMMPACT recommendations

There is tremendous interpatient variability in the response to analgesic therapy (even for efficacious treatments), which can be the source of great frustration in clinical practice. This has led to calls for “precision medicine” or personalized pain therapeutics (ie, empirically based algorithms that determine the optimal treatments, or treatment combinations, for individual patients) that would presumably improve both the clinical care of patients with pain and the success rates for putative analgesic drugs in phase 2 and 3 clinical trials. However, before implementing this approach, the characteristics of individual patients or subgroups of patients that increase or decrease the response to a specific treatment need to be identified. The challenge is to identify the measurable phenotypic characteristics of patients that are most predictive of individual variation in analgesic treatment outcomes, and the measurement tools that are best suited to evaluate these characteristics. In this article, we present evidence on the most promising of these phenotypic characteristics for use in future research, including psychosocial factors, symptom characteristics, sleep patterns, responses to noxious stimulation, endogenous pain-modulatory processes, and response to pharmacologic challenge. We provide evidence-based recommendations for core phenotyping domains and recommend measures of each domain.

Preoperative quantitative sensory testing and robot-assisted laparoscopic hysterectomy for endometrial cancer: can chronic postoperative pain be predicted?

Objectives Chronic postoperative pain is prevalent after robot-assisted laparoscopic hysterectomy for endometrial cancer. Preoperative Quantitative Sensory Testing (QST) has been utilized to identify patients at risk of developing chronic postoperative pain after a range of surgical procedures. The aim of this prospective, observational study was to (1) determine the prevalence of chronic postoperative pain, (2) assess selected preoperative risk factors for chronic postoperative pain, and (3) evaluate if preoperative QST profiling could predict the development of chronic postoperative pain following robot-assisted laparoscopic hysterectomy for endometrial cancer. Methods One-hundred and sixty consecutive patients were included and handheld pressure algometry, cuff pressure algometry, temporal summation of pain, conditioned pain modulation, and heat pain thresholds were assessed prior to surgery. Patients were asked to fill out a questionnaire concerning pain in the pre- and post-operative time period six months after surgery. Chronic postoperative pain was defined as persistent, moderate to severe pain (mean visual analogue scale (VAS)≥3) on a daily basis six months after surgery. Results The prevalence of chronic postoperative pain after robot-assisted laparoscopic hysterectomy for endometrial cancer was of 13.6% (95% CI 8.4-20.4%). Patients that would develop chronic postoperative pain had a lower BMI (p=0.032), a higher prevalence of preoperative pelvic pain (p<0.001), preoperative heat pain hyperalgesia (p=0.043) and a higher level of acute postoperative pain (p<0.001) when compared to patients that would not develop chronic postoperative pain. A logistic regression model demonstrated that the presence of preoperative pelvic pain was a significant, independent predictive risk factor for development of chronic postoperative pain (OR=6.62, 95% CI 2.26-19.44), whereas none of the QST parameters could predict postoperative pain. Conclusions Preoperative QST assessment could not predict the development of chronic postoperative pain despite preoperative heat pain hyperalgesia in patients that would develop chronic postoperative pain.

Interdisciplinary Teams in Endometriosis Care

Endometriosis-associated chronic pelvic pain can at times be a complex problem that is resistant to standard medical and surgical therapies. Multiple comorbidities and central sensitization may be at play and must be recognized with the help of a thorough history and physical examination. If a complex pain problem is identified, most endometriosis expert reviews and guidelines recommend multidisciplinary care. However, there are no specific recommendations about what should be the components of this approach and how that type of team care should be delivered. There is evidence showing the effectiveness of specific interventions such as pain education, physical therapy, psychological therapies, and pharmacotherapies for the treatment of chronic pain. Interdisciplinary team models have been well studied and validated in other chronic pain conditions such as low back pain. The published evidence in support of interdisciplinary teams for endometriosis-associated chronic pain is more limited but appears promising. Based on the available evidence, a model for an interdisciplinary team approach for endometriosis care is outlined.

Is Preoperative Quantitative Sensory Testing Related to Persistent Postsurgical Pain? A Systematic Literature Review

Persistent postsurgical pain (PPSP) is a common complication of surgery that significantly affects quality of life. A better understanding of which patients are likely to develop PPSP would help to identify when perioperative and postoperative pain management may require specific attention. Quantitative sensory testing (QST) of a patient's preoperative pain perception is associated with acute postoperative pain, and acute postoperative pain is a risk factor for PPSP. The direct association between preoperative QST and PPSP has not been reviewed to date. In this systematic review, we assessed the relationship of preoperative QST to PPSP. We searched databases with components related to (1) preoperative QST; (2) association testing; and (3) PPSP. Two authors reviewed all titles and abstracts for inclusion. Inclusion criteria were as follows: (1) QST performed before surgery; (2) PPSP assessed ≥3 months postoperatively; and (3) the association between QST measures and PPSP is investigated. The search retrieved 905 articles; 24 studies with 2732 subjects met inclusion criteria. Most studies (22/24) had moderate to high risk of bias in multiple quality domains. Fourteen (58%) studies reported a significant association between preoperative QST and PPSP. Preoperative temporal summation of pain (4 studies), conditioned pain modulation (3 studies), and pressure pain threshold (3 studies) showed the most frequent association with PPSP. The strength of the association between preoperative QST and PPSP varied from weak to strong. Preoperative QST is variably associated with PPSP. Measurements related to central processing of pain may be most consistently associated with PPSP.

Effects of Additional Intraoperative Administration of Sufentanil on Postoperative Pain, Stress and Inflammatory Responses in Patients Undergoing Laparoscopic Myomectomy: A Double-Blind, Randomized, Placebo-Controlled Trial

Purpose

Although pain after laparoscopic surgery is assumed to be minor, many women still suffer from unexpected postoperative pain. Thus, we aimed to assess whether additional intraoperative administration of sufentanil could help to improve postoperative pain and related agitation, stress, and inflammation response in patients undergoing laparoscopic myomectomy.

Patients and Methods

Forty female patients with uterine myoma scheduled for laparoscopic myomectomy under general anesthesia were randomized to receive sufentanil (group T, n=20) or normal saline (group C, n=20) 1h before the end of the surgery. The postoperative pain, agitation, stress, inflammation, and adverse effects were measured.

Results

As the primary outcome, the visual analog scale (VAS) pain score was significantly reduced in group T as compared with group C at each measured time point in a post-anesthesia care unit (PACU), VAS 5 min (31.5 ± 2.7 vs 40.6 ± 5.6) (P<0.001), VAS 30 min (36.5 ± 4.5 vs 46.0 ± 2.9) (P<0.001), VAS 1h (37.8 ± 4.0 vs 48.6 ± 5.5) (P<0.001). The secondary outcomes, including the sedation agitation scale (SAS) scores, plasma concentrations of epinephrine and norepinephrine, and the levels of plasma interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-α) in group T were remarkably lower than those in group C (P < 0.001). The cough cases in group T also showed a significant reduction in comparison with group C (P < 0.05). In addition, the anesthetic recovery time, including the spontaneous breathing recovery time and extubation time, were not significantly different between the two groups, as were the cases of respiratory depression and postoperative delirium (P > 0.05).

Conclusion

For patients undergoing laparoscopic myomectomy, administration of sufentanil 1 h before the end of surgery shows excellent analgesic and sedative effects, alleviated postoperative stress and inflammatory responses, reduced incidence of cough, without prolonging anesthetic recovery time and increasing adverse reactions.

Viscero-visceral hyperalgesia in dysmenorrhoea plus previous urinary calculosis: Role of myofascial trigger points and their injection treatment in the referred area

BACKGROUND

Women with dysmenorrhoea plus symptomatic urinary calculosis experience enhanced pain and referred muscle hyperalgesia from both conditions than women with one condition only (viscero-visceral hyperalgesia). The study aimed at verifying if enhanced dysmenorrhoea persists after urinary stone elimination in comorbid women and if local anaesthetic inactivation of myofascial trigger points (TrPs) in the lumbar area (of urinary pain referral) also relieves dysmenorrhoea.

METHODS

Thirty-one women with dysmenorrhoea plus previous urinary calculosis (Dys+PrCal) and lumbar TrPs, and 33 women with dysmenorrhoea without calculosis (Dys) underwent a 1-year assessment of menstrual pain and muscle hyperalgesia in the uterus-referred area (electrical pain threshold measurement in rectus abdominis, compared with thresholds of 33 healthy controls). At the end of the year, 16 comorbid patients underwent inactivation of TrPs through anaesthetic injections, whereas the remaining 12 received no TrP treatment. Both groups were monitored for another year at the end of which thresholds were re-measured.

RESULTS

In year1, Dys+PrCal presented significantly more painful menstrual cycles and lower abdominal thresholds than Dys, thresholds of both groups being significantly lower than normal (p < .001). Anaesthetic treatment versus no treatment of the lumbar TrP significantly reduced the number of painful cycles during year2 and significantly increased the abdominal thresholds (p < .0001).

CONCLUSION

Viscero-visceral hyperalgesia between uterus and urinary tract may persist after stone elimination due to nociceptive inputs from TrPs in the referred urinary area, since TrPs treatment effectively reverses the enhanced menstrual symptoms. The procedure could represent an integral part of the management protocol in these conditions.

SIGNIFICANCE

A past pain process from an internal organ can continue enhancing pain expression from a painful disease in another neuromerically connected organ (viscero-visceral hyperalgesia) if secondary myofascial trigger points (TrPs) developed in the referred area at the time of the previous visceral disease. Inactivation of these TrPs reverts the enhancement. Assessment and treatment of TrPs in referred areas from past visceral pain conditions should be systematically carried out to better control pain from current diseases in other viscera.

AAAPT Diagnostic Criteria for Acute Abdominal and Peritoneal Pain After Surgery

Abdominal and peritoneal pain after surgery is common and burdensome, yet the lack of standardized diagnostic criteria for this type of acute pain impedes basic, translational, and clinical investigations. The collaborative effort among the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks, American Pain Society, and American Academy of Pain Medicine Pain Taxonomy (AAAPT) provides a systematic framework to classify acute painful conditions. Using this framework, a multidisciplinary working group reviewed the literature and developed core diagnostic criteria for acute abdominal and peritoneal pain after surgery. In this report, we apply the proposed AAAPT framework to 4 prototypical surgical procedures resulting in abdominal and peritoneal pain as examples: cesarean delivery, cholecystectomy, colorectal surgical procedures, and pancreas resection. These diagnostic criteria address the 3 most common surgical procedures performed in the United States, capture diverse surgical approaches, and may also be applied to other surgical procedures resulting in abdominal and peritoneal pain. Additional investigation regarding the validity and reliability of this framework will facilitate its adoption in research that advances our comprehension of mechanisms, deliver better treatments, and help prevent the transition of acute to chronic pain after surgery in the abdominal and peritoneal region. PERSPECTIVE: Using AAAPT, we present key diagnostic criteria for acute abdominal and peritoneal pain after surgery. We provide a systematic classification using 5 dimensions for abdominal and peritoneal pain that occurs after surgery, in addition to 4 specific surgical procedures: cesarean delivery, cholecystectomy, colorectal surgical procedures, and pancreas resection.

Endometriosis and pain in the adolescent- striking early to limit suffering: A narrative review

Endometriosis, a condition in which uterine tissue grows outside the uterus, is a debilitating disease, affecting millions of women and costing the United States approximately $78 billion annually in pain- related disability. It is also the leading cause of chronic pelvic pain (CPP), which is often unresponsive to existing treatments. Adolescent women with the disease are at particular risk as there are often significant diagnostic delays, which in turn can exacerbate pain. Research and treatment guidelines for adolescents with endometriosis are largely based on studies for adult women due to the limited number of studies focusing on adolescents. The current paper critically reviews the literature as it pertains to endometriosis pathophysiology, mechanisms contributing to CPP, and treatment implications and recommendations with a focus on gaps related to adolescents.

Vulvodynia and chronic pelvic pain in a gynecologic outpatient clinic

Introduction: Vulvodynia and chronic pelvic pain are common but underdiagnosed chronic gynecologic pain syndromes. Insufficient knowledge regarding prevalence, typical pain patterns and associated factors contribute to delayed diagnosis. The present study explored the symptoms and characteristics of women presenting with vulvodynia and/or chronic pelvic pain to a gynecologic outpatient clinic. Materials and methods: Electronic charts of women diagnosed with vulvodynia and/or chronic pelvic pain between January 2010 and December 2015 were reviewed. Type of pain, duration of symptoms, previous medical assessments and therapies, comorbidities and patient characteristics were analyzed with descriptive statistics. Results: One hundred and twenty-seven women (mean age 36, range 18-75 years) met the diagnostic criteria for chronic gynecologic pain syndromes. Sixty-five women were diagnosed with CPP only, 42 with vulvodynia and 20 with both conditions. Endometriosis was suspected or diagnosed in 35 (54%) women with CPP. History of pain ranged from 3 months to 20 years. Comorbidities were common, with 40% of women being diagnosed with depression or other mood disorders, 15% with urological and 9% with gastrointestinal conditions. Conclusions: There is a need for increased awareness regarding vulvodynia and CPP among health care providers. A comprehensive history is important for adequate diagnosis.

Pain, psychosocial tests, pain sensitization and laparoscopic pelvic surgery

BACKGROUND AND AIMS

Individuals with non-acute pain are challenged with variable pain responses following surgery as well as psychological challenges, particularly depression and catastrophizing. The purpose of this study was to compare pre- and postoperative psychosocial tests and the associated presence of sensitization on a cohort of women undergoing elective laparoscopic surgery for non-acute pain defined as pain sufficient for surgical investigation without persistent of chronic pain.

METHODS

The study was a secondary analysis of a previous report (Am J Obstet Gynecol 2014 Oct;211(4):360-8.). The study was a prospective cohort trial of 77 women; 61 with non-acute pain and 16 women for a tubal ligation. The women had the following tests: Pain Disability Index, Pain Catastrophizing Scale, CES-D (Center for Epidemiologic Studies Depression Scale) depression scale and the McGill Pain Scale (short form) as well as their average pain score and the presence of pain sensitization. All test scores were correlated together and comparisons were done using paired t-test.

RESULTS

There were reductions in pain and psychosocial test scores that were significantly correlated. Pre-operative sensitization indicated greater changes in psychosocial tests.

CONCLUSIONS

There was a close association of tests of psychosocial status with average pain among women having surgery on visceral tissues. Incorporation of these tests in the pre- and postoperative evaluation of women having laparoscopic surgery appears to provide a means to a broader understanding of the woman's pain experience.

Spinal Anesthesia and Spinal Anesthesia with Subdiaphragmatic Lidocaine in Shoulder Pain Reduction for Gynecological Laparoscopic Surgery: A Randomized Clinical Trial

OBJECTIVE

The aim of this study was to compare the effectiveness of spinal anesthesia with subdiaphragmatic lidocaine at the beginning of surgery versus spinal anesthesia in pain reduction for gynecological laparoscopic surgery.

METHODS

This was a clinical trial conducted in Arash Hospital, Tehran, Iran. Eighty-four patients were randomized to either spinal anesthesia with subdiaphragmatic lidocaine, spinal anesthesia, or general anesthesia (GA). The primary outcome was patients' pain perception during surgery, 2, 4, 6, and 12 hours after surgery, and prior to discharge and was assessed by visual analogue scale (VAS).

RESULTS

The results showed that there are no significant changes in pain perception over time in none of the three groups (F(4,76) = 0.37, P = 0.82). The severity of pain experienced by patients at all-time interval after surgery was similar between groups [F(2,79) = 0.54, P = 0.58].

CONCLUSION

The use of subdiaphragmatic lidocaine at the beginning of surgery combined with spinal anesthesia was not associated with a statistically significant difference in patients' postoperative VAS scores compared to spinal anesthesia and GA during and after gynecological surgical procedures. The study was registered in Iranian Registry of Clinical Trial by the number of IRCT2016022226698N1.

Patient phenotyping in clinical trials of chronic pain treatments: IMMPACT recommendations

There is tremendous interpatient variability in the response to analgesic therapy (even for efficacious treatments), which can be the source of great frustration in clinical practice. This has led to calls for "precision medicine" or personalized pain therapeutics (ie, empirically based algorithms that determine the optimal treatments, or treatment combinations, for individual patients) that would presumably improve both the clinical care of patients with pain and the success rates for putative analgesic drugs in phase 2 and 3 clinical trials. However, before implementing this approach, the characteristics of individual patients or subgroups of patients that increase or decrease the response to a specific treatment need to be identified. The challenge is to identify the measurable phenotypic characteristics of patients that are most predictive of individual variation in analgesic treatment outcomes, and the measurement tools that are best suited to evaluate these characteristics. In this article, we present evidence on the most promising of these phenotypic characteristics for use in future research, including psychosocial factors, symptom characteristics, sleep patterns, responses to noxious stimulation, endogenous pain-modulatory processes, and response to pharmacologic challenge. We provide evidence-based recommendations for core phenotyping domains and recommend measures of each domain.

Are preoperative experimental pain assessments correlated with clinical pain outcomes after surgery? A systematic review

BACKGROUND

Pain after surgery is not uncommon with 30% of patients reporting moderate to severe postoperative pain. Early identification of patients prone to postoperative pain may be a step forward towards individualized pain medicine providing a basis for improved clinical management through treatment strategies targeting relevant pain mechanisms in each patient. Assessment of pain processing by quantitative sensory testing (QST) prior to surgery has been proposed as a method to identify patients at risk for postoperative pain, although results have been conflicting. Since the last systematic review, several studies investigating the association between postoperative pain and more dynamic measures of pain processing like temporal summation of pain and conditioned pain modulation have been conducted.

OBJECTIVES

According to the PRISMA guidelines, the aim of this systematic review was to evaluate whether assessment of experimental pain processing including measures of central pain mechanisms prior to surgery was associated with pain intensity after surgery.

METHODS

Systematic database searches in PubMed and EMBASE with the following search components: QST, association, and postoperative pain, for studies that assessed the association between QST and pain after surgery were performed. Two authors independently reviewed all titles and abstracts to assess their relevance for inclusion. Studies were included if (1) QST was performed prior to surgery, (2) pain was assessed after surgery, and (3) the association between QST and pain after surgery was investigated. Forty-four unique studies were identified, with 30 studies on 2738 subjects meeting inclusion criteria. The methodological quality of the include studies was assessed and data extraction included study population, type of surgery, QST variables, clinical pain outcome measure and main result.

RESULTS

Most studies showed moderate to high risk of bias. Type of surgery investigated include 7 studies on total knee replacement, 5 studies on caesarean section, 4 studies on thoracic surgery, 2 studies on herniotomy, 2 studies on hysterectomy/myomectomy, 1 study on tubal ligation, 1 study on gynecologic laparoscopy, 1 study on arthroscopic knee surgery, 1 study on shoulder surgery, 1 study on disc herniation surgery, 1 study on cholecystectomy, 1 study on percutaneous nephrolithotomy, 1 study on molar surgery, 1 study on abdominal surgery, and 1 study on total knee replacement and total hip replacement. The majority of the preoperative QST variables showed no consistent association with pain intensity after surgery. Thermal heat pain above the pain threshold and temporal summation of pressure pain were the QST variables, which showed the most consistent association with acute or chronic pain after surgery.

CONCLUSIONS

QST before surgery does not consistently predict pain after surgery. High quality studies investigating the presence of different QST variables in combination or along with other pain-related psychosocial factors are warranted to confirm the clinical relevance of QST prior to surgery.

IMPLICATIONS

Although preoperative QST does not show consistent results, future studies in this area should include assessment of central pain mechanisms like temporal summation of pressure pain, conditioned pain modulation, and responses to pain above the pain threshold since these variables show promising associations to pain after surgery.

Laparoscopic surgery: a narrative review of pharmacotherapy in pain management

Laparoscopic surgery is widespread, and an increasing number of surgeries are performed laparoscopically. Early pain after laparoscopy can be similar or even more severe than that after open surgery. Thus, proactive pain management should be provided. Pain after laparoscopic surgery is derived from multiple origins; therefore, a single agent is seldom sufficient. Pain is most effectively controlled by a multimodal, preventive analgesia approach, such as combining opioids with non-opioid analgesics and local anaesthetics. Wound and port site local anaesthetic injections decrease abdominal wall pain by 1-1.5 units on a 0-10 pain scale. Inflammatory pain and shoulder pain can be controlled by NSAIDs or corticosteroids. In some patient groups, adjuvant drugs, ketamine and α2-adrenergic agonists can be helpful, but evidence on gabapentinoids is conflicting. In the present review, the types of pain that need to be taken into account while planning pain management protocols and the wide range of analgesic options that have been assessed in laparoscopic surgery are critically assessed. Recommendations to the clinician will be made regarding how to manage acute pain and how to prevent persistent postoperative pain. It is important to identify patients at the highest risk for severe and prolonged post-operative pain, and to have a proactive strategy in place for these individuals.

Parecoxib increases muscle pain threshold and relieves shoulder pain after gynecologic laparoscopy: a randomized controlled trial

Objectives

Postlaparoscopic shoulder pain (PLSP) remains a common problem after laparoscopies. The aim of this study was to investigate the correlation between pressure pain threshold (PPT) of different muscles and PLSP after gynecologic laparoscopy, and to explore the effect of parecoxib, a cyclooxygenase-2 inhibitor, on the changes of PPT.

Materials and methods

The patients were randomly allocated into two groups; group P and group C. In group P, parecoxib 40 mg was intravenously infused at 30 minutes before surgery and 8 and 20 hours after surgery. In group C, normal saline was infused at the corresponding time point. PPT assessment was performed 1 day before surgery and at postoperative 24 hours by using a pressure algometer at bilateral shoulder muscles (levator scapulae and supraspinatus) and forearm (flexor carpi ulnaris). Meanwhile, bilateral shoulder pain was evaluated through visual analog scale score at 24 hours after surgery.

Results

Preoperative PPT level of the shoulder, but not of the forearm, was significantly and negatively correlated with the intensity of ipsilateral PLSP. In group C, PPT levels of shoulder muscles, but not of forearm muscles, decreased after laparoscopy at postoperative 24 hours. The use of parecoxib significantly improved the decline of PPT levels of bilateral shoulder muscles (all P<0.01). Meanwhile, parecoxib reduced the incidence of PLSP (group P: 45% vs group C: 83.3%; odds ratio: 0.164; 95% confidence interval: 0.07–0.382; P<0.001) and the intensity of bilateral shoulder pain (both P<0.01).

Conclusion

Preoperative PPT levels of shoulder muscles are closely associated with the severity of shoulder pain after gynecologic laparoscopy. PPT levels of shoulder muscles, but not of forearm muscles, significantly decreased after surgery. Parecoxib improved the decrease of PPT and relieved PLSP.

Risk factors associated with postoperative pain after ophthalmic surgery: a prospective study

BACKGROUND

Risk factors associated with postoperative pain intensity and duration, as well as consumption of analgesics after ophthalmic surgery are poorly understood.

METHODS

A prospective study was conducted among adults (N=226) who underwent eye surgery at the University Hospital Split, Croatia. A day before the surgery, the patients filled out questionnaires assessing personality, anxiety, pain catastrophizing, sociodemographics and were given details about the procedure, anesthesia, and analgesia for each postoperative day. All scales were previously used for the Croatian population. The intensity of pain was measured using a numerical rating scale from 0 to 10, where 0 was no pain and 10 was the worst imaginable pain. The intensity of pain was measured before the surgery and then 1 hour, 3 hours, 6 hours, and 24 hours after surgery, and then once a day until discharge from the hospital. Univariate and multivariate analyses were performed.

RESULTS

A multivariate analysis indicated that independent predictors of average pain intensity after the surgery were: absence of premedication before surgery, surgery in general anesthesia, higher pain intensity before surgery and pain catastrophizing level. Independent predictors of postoperative pain duration were intensity of pain before surgery, type of anesthesia, and self-assessment of health. Independent predictors of pain intensity ≥5 during the first 6 hours after the procedure were the type of procedure, self-assessment of health, premedication, and the level of pain catastrophizing.

CONCLUSION

Awareness about independent predictors associated with average postoperative pain intensity, postoperative pain duration, and occurrence of intensive pain after surgery may help health workers to improve postoperative pain management in ophthalmic surgery.