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Introduction/Aims: Available studies on scoliosis surgery in spinal muscular atrophy (SMA) have focused on the primary outcome of the procedure—the correction of the curve—whereas research focusing on secondary outcomes is scarce. We aimed to investigate postsurgical changes in respiratory function, motor function, weight, pain, and satisfaction. Methods: We retrospectively reviewed the clinical notes of 32 disease‐modifying treatment‐naïve patients (26 SMA2, 6 nonambulant SMA3). We also performed investigator‐developed phone interviews and conducted a focus group with families on postsurgical satisfaction. Results: Mean annual rate of forced vital capacity percent decline improved in SMA2: −3.2% postsurgery versus −6.9% presurgery (p <.001), with similar trajectories in SMA3. Gross motor functional scores (Hammersmith Functional Motor Scale) available in 12/32 dropped immediately after surgery: median loss of 6.5 points, with relatively spared upper limb function. Weight z‐scores postsurgery dropped in 16/32, requiring food supplements (5/16); one/16 lost >5% of total weight requiring gastrostomy. Postsurgical pain was frequently reported, especially hip pain (13/32). Overall, 10/10 patients/parents participating in the phone interview rated the procedure as very successful for posture and physical appearance. Nonetheless, 7/10 reported postsurgical pain, reduced mobility, and unmet care needs. The seven patients/parents attending the focus group highlighted lack of intensive physiotherapy programs, occupational therapy assistance, and psychological support as postsurgical unmet care needs. Discussion: This study reports a positive impact of scoliosis surgery on respiratory function and overall satisfaction with posture and physical appearance. The observed negative impact on the other outcomes highlights the importance of multidisciplinary approaches to improve postoperative management. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effectiveness of diverse postoperative analgesic techniques in laparoscopic colorectal surgery and ascertain whether systemic administration of nalbuphine is a suitable alternative for this type of procedure. Sixty-nine patients suffering from colorectal cancer and undergoing laparoscopic surgery were randomly divided into three groups (n = 23, per group). Group R received patient-controlled epidural analgesia (PCEA) with ropivacaine. Group M received patient-controlled intravenous analgesia (PCIA) with morphine. Group N received PCIA with nalbuphine. Pain at rest (PAR), movement-evoked pain (MEP), stress hormone and any complications during the 72 hours after surgery were recorded. Additionally, chronic post-surgical pain (CPSP) at 3 months and 6 months were also recorded. There was no significant difference in PAR among the 3 groups. However, patients in Group N had a higher intensity of MEP compared to those in Group R after surgery (p < 0.05). There was no significant difference in CPSP at 6 months among the 3 groups (p > 0.05), but the incidence of CPSP at 3 months was higher in Group N (p = 0.01, as compared to Group R). The occurrences of pruritus and postoperative nausea and vomiting (PONV) were observed to be considerably greater in Group M as compared to the other two groups (p < 0.05). In conclusion, PCEA is more effective than PCIA with nalbuphine in reducing postoperative MEP and CPSP at 3 months after laparoscopic colorectal surgery. However, there was no significant difference between PCEA and PCIA with nalbuphine in reducing CPSP at 6 months. Although morphine and nalbuphine have the similar analgesic effects, morphine is associated with more side effects. Therefore, PCIA with nalbuphine might be a good option for patients who are not suitable for PCEA or have a high risk for PONV or pruritus. [ABSTRACT FROM AUTHOR]

Moderate-to-severe acute postsurgical pain (APSP) can prolong the recovery and worsen the prognosis of patients who undergo spinal surgery. Esketamine and pregabalin may resolve APSP without causing hyperpathia or respiratory depression after surgery. However, there are other risks, such as dissociative symptoms. We designed a randomized controlled trial to investigate the effect of the combination of these 2 drugs on the incidence of APSP in patients who underwent resection of spinal neoplasms. Patients aged 18 to 65 years were randomized to receive esketamine (a bolus dose of 0.5 mg⋅kg-1 and an infusion dose of 0.12 mg⋅kg-1⋅h-1 for 48 hours after surgery) combined with oral pregabalin (75-150 mg/day, starting 2 hours before surgery and ending at 2 weeks after surgery) or an identical volume of normal saline and placebo capsules. The primary outcome was the proportion of patients with moderate-to-severe APSP (visual analog scale score ≥ 40) during the first 48 hours after surgery. Secondary outcomes included the incidence of drug-related adverse events. A total of 90 patients were randomized. The incidence of moderate-to-severe APSP in the combined group (27.3%) was lower than that in the control group (60.5%) during the first 48 hours after surgery (odds ratio = 0.25, 95% CI 5 0.10-0.61; P = 0.002). The occurrence of mild dissociative symptoms was higher in the combined group than in the control group (18.2% vs 0%). In conclusion, esketamine combined with pregabalin could effectively alleviate APSP after spinal surgery, but an analgesic strategy might increase the risk of mild dissociative symptoms. [ABSTRACT FROM AUTHOR]

The article discusses the patterns of opioid use after surgical discharge and the need for guidelines on opioid prescribing practices. The authors conducted a study of postsurgical patients from 25 countries to evaluate opioid prescribing practices and patient consumption patterns. They found that opioid overprescribing at the time of hospital discharge is more prevalent than previously thought. The article emphasizes the importance of specialized multidisciplinary programs, such as transitional pain services, to manage postsurgical pain and appropriately wean patients off opioids. The authors also suggest implementing a part-fill prescription system to reduce the quantity of opioids dispensed initially. Overall, the article highlights the need for improved opioid stewardship practices and increased support for patients struggling with postsurgical pain. [Extracted from the article]

Nowadays, with the start of hostilities in Ukraine, the number of people with injuries has increased and continues to grow. Of course, one of the main issues facing by medical professionals is preventing complications and restoring sufficient functional capacity. Pain is one of the protective mechanisms of the human body; its prolonged course is one of the most important causes for reducing the quality of life and limiting a person’s work capacity. Acute pain is positioned as the body’s main signal for help, usually as a disease symptom, while chronic pain can be an independent nosological unit and mostly appears after primary cause. Secondary chronic pain is one of the injury consequences that can occur and significantly worsen the patient’s prognosis and reduce quality of life. Prevention of the secondary chronic pain is possible if all prerequisites are known. Furthermore, the human body interacts with a complex community of bacteria, fungi, and viruses. Several microorganisms create the microbiome of the skin, which ensures its barrier function and plays an important role in the immune response in wounds. These processes are not always predictable, and both positive and negative effects on wound healing can be observed. After all, the duration of wound healing directly depends on the type of microorganisms and their sensitivity to the antibiotic treatment. The long process of wound surface healing can lead more likely to a violation of all physiological processes in this body part. This can be quite an important factor in chronic pain occurrence.

AbstractChronic pain affects more than 50 million Americans. Treatments remain inadequate, in large part, because the pathophysiological mechanisms underlying the development of chronic pain remain poorly understood. Pain biomarkers could potentially identify and measure biological pathways and phenotypical expressions that are altered by pain, provide insight into biological treatment targets, and help identify at-risk patients who might benefit from early intervention. Biomarkers are used to diagnose, track, and treat other diseases, but no validated clinical biomarkers exist yet for chronic pain. To address this problem, the National Institutes of Health Common Fund launched the Acute to Chronic Pain Signatures (A2CPS) program to evaluate candidate biomarkers, develop them into biosignatures, and discover novel biomarkers for chronification of pain after surgery. This article discusses candidate biomarkers identified by A2CPS for evaluation, including genomic, proteomic, metabolomic, lipidomic, neuroimaging, psychophysical, psychological, and behavioral measures. Acute to Chronic Pain Signatures will provide the most comprehensive investigation of biomarkers for the transition to chronic postsurgical pain undertaken to date. Data and analytic resources generatedby A2CPS will be shared with the scientific community in hopes that other investigators will extract valuable insights beyond A2CPS's initial findings. This article will review the identified biomarkers and rationale for including them, the current state of the science on biomarkers of the transition from acute to chronic pain, gaps in the literature, and how A2CPS will address these gaps.

Abstract While neurosurgical interventions are frequently used in laboratory mice, refinement efforts to optimize analgesic management based on multimodal approaches appear to be rather limited. Therefore, we compared the efficacy and tolerability of combinations of the non-steroidal anti-inflammatory drug carprofen, a sustained-release formulation of the opioid buprenorphine, and the local anesthetic bupivacaine with carprofen monotherapy. Female and male C57BL/6J mice were subjected to isoflurane anesthesia and an intracranial electrode implant procedure. Given the multidimensional nature of postsurgical pain and distress, various physiological, behavioral, and biochemical parameters were applied for their assessment. The analysis revealed alterations in Neuro scores, home cage locomotion, body weight, nest building, mouse grimace scales, and fecal corticosterone metabolites. A composite measure scheme allowed the allocation of individual mice to severity classes. The comparison between groups failed to indicate the superiority of multimodal regimens over high-dose NSAID monotherapy. In conclusion, our findings confirmed the informative value of various parameters for assessment of pain and distress following neurosurgical procedures in mice. While all drug regimens were well tolerated in control mice, our data suggest that the total drug load should be carefully considered for perioperative management. Future studies would be of interest to assess potential synergies of drug combinations with lower doses of carprofen.

While neurosurgical interventions are frequently used in laboratory mice, refinement efforts to optimize analgesic management based on multimodal approaches appear to be rather limited. Therefore, we compared the efficacy and tolerability of combinations of the non-steroidal anti-inflammatory drug carprofen, a sustained-release formulation of the opioid buprenorphine, and the local anesthetic bupivacaine with carprofen monotherapy. Female and male C57BL/6J mice were subjected to isoflurane anesthesia and an intracranial electrode implant procedure. Given the multidimensional nature of postsurgical pain and distress, various physiological, behavioral, and biochemical parameters were applied for their assessment. The analysis revealed alterations in Neuro scores, home cage locomotion, body weight, nest building, mouse grimace scales, and fecal corticosterone metabolites. A composite measure scheme allowed the allocation of individual mice to severity classes. The comparison between groups failed to indicate the superiority of multimodal regimens over high-dose NSAID monotherapy. In conclusion, our findings confirmed the informative value of various parameters for assessment of pain and distress following neurosurgical procedures in mice. While all drug regimens were well tolerated in control mice, our data suggest that the total drug load should be carefully considered for perioperative management. Future studies would be of interest to assess potential synergies of drug combinations with lower doses of carprofen. [ABSTRACT FROM AUTHOR]

Postoperative pain is a major clinical problem imposing a significant burden on patients and society. In a survey 2 years after orthopedic surgery, 57%of patients reported persisting postoperative pain. However, only limited progress has been made in the development of safe and effective therapies to prevent the onset and chronification of pain after orthopedic surgery. We established a tibial fracturemouse model that recapitulates clinically relevant orthopedic trauma surgery, which causes changes in neuropeptide levels in dorsal root ganglia and sustained neuroinflammation in the spinal cord. Here, we monitored extended pain behavior in this model, observing chronic bilateral hindpaw mechanical allodynia in both male and female C57BL/6J mice that persisted for .3 months after surgery. We also tested the analgesic effects of a novel, minimally invasive, bioelectronic approach to percutaneously stimulate the vagus nerve (termed percutaneous vagus nerve stimulation [pVNS]). Weekly pVNS treatment for 30 minutes at 10 Hz for 3 weeks after the surgery strongly reduced pain behaviors comparedwith untreated controls. Percutaneous vagus nerve stimulation also improved locomotor coordination and accelerated bone healing. In the dorsal root ganglia, vagal stimulation inhibited the activation of glial fibrillary acidic protein-positive satellite cells but without affectingmicroglial activation. Overall, these data provide novel evidence supportive of theuseof pVN Stop revent post operative pain and inform translational studies to test antinociceptive effects of bioelectronic medicine in the clinic. [ABSTRACT FROM AUTHOR]

Facial grimacing is used to quantify spontaneous pain in mice and other mammals, but scoring relies on humans with different levels of proficiency. Here, we developed a cloud-based software platform called PainFace (http://painface.net) that uses machine learning to detect 4 facial action units of the mouse grimace scale (orbitals, nose, ears, whiskers) and score facial grimaces of blackcoated C57BL/6 male and female mice on a 0 to 8 scale. Platform accuracy was validated in 2 different laboratories, with 3 conditions that evoke grimacing--laparotomy surgery, bilateral hindpaw injection of carrageenan, and intraplantar injection of formalin. PainFace can generate up to 1 grimace score per second from a standard 30 frames/s video, making it possible to quantify facial grimacing over time, and operates at a speed that scales with computing power. By analyzing the frequency distribution of grimace scores, we found that mice spent 7x more time in a "high grimace" state following laparotomy surgery relative to sham surgery controls. Our study shows that PainFace reproducibly quantifies facial grimaces indicative of nonevoked spontaneous pain and enables laboratories to standardize and scale-up facial grimace analyses. [ABSTRACT FROM AUTHOR]

Background: Buprenorphine (BPN) is a widely used analgesic in the pediatric population, although there are few studies on the pharmacokinetics and pharmacodynamics of this drug. Objective: The objective was to characterize the pharmacokinetics of BPN after intravenous administration and analyze the effect of age, gender, weight, height, body mass index (BMI), and drug-drug interactions as covariates. Methods: Ninety-nine children (2-10 years), who underwent orthopedic surgery under regional, general, or combined anesthesia were included. Patients evaluated according to the American Society of Anesthesiologists Physical Status Classification, who received intravenous BPN 2 μg/kg were enrolled. Blood was collected from 1-240 min. Drug plasma concentrations were determined by LC-MS/MS. Population pharmacokinetic parameters were obtained with Monolix 2021R1 software. Pearson's correlation and/or ANOVA were used for statistical analysis. Results: Age was associated with changes in clearance and central compartment volume and the female gender was associated with lower intercompartmental clearance, while BMI modified clearance, central and peripheral compartment volume. Concomitant administration of BPN with fentanyl and dexamethasone produced decreases in clearance. Conclusions: The covariates of sex, age, and BMI are directly related to the increase or decrease in BPN pharmacokinetic parameters. [ABSTRACT FROM AUTHOR]

Background: Chronic postsurgical pain (CPSP) presents a considerable healthcare challenge, impacting patients, and healthcare providers, particularly in the context of gastrointestinal surgery. The notable incidence of CPSP in this specific surgical domain emphasizes the need to identify patients with a high risk of developing this condition. Despite various studies exploring this topic, a comprehensive systematic review focusing on prognostic factors of CPSP following gastrointestinal surgery is currently lacking. Therefore, the aim of this systematic review is, through systematically examination of existing literature, to assess both established and potentially novel prognostic factors, associated with CPSP following gastrointestinal surgery. Methods: Adhering to the Cochrane Handbook and the Preferred Reporting Items for Systematic review and Meta‐Analysis Protocols (PRISMA‐P) checklist, we will use pre‐established criteria based on Population, Intervention, Comparator, Outcome, Timing, and Setting (PICOT‐S), to determine eligibility for inclusion. Essentially, this entails studies reporting on prognostic factors of CPSP following gastrointestinal surgery. Relevant studies will be identified through systematic searches in medical databases, examination of reference lists from included studies, and screening of Clinicaltrials.gov. No restrictions will be imposed regarding language, publication time or source, and both randomized trials and observational studies will be included. Data extraction will follow the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of prognostic factor studies (CHARMS‐PF) and for quality assessment, we will use the Quality in Prognosis Studies (QUIPS) tool. Results: The aim for the systematic review is to identify and assess the prognostic value of potential factors for the development of CPSP following gastrointestinal surgery. Conclusion: By creating a comprehensive overview of important prognostic factors for the development of CPSP following gastrointestinal surgery, the findings of this systematic review have the potential to guide future research and to enhance patient information resources. [ABSTRACT FROM AUTHOR]

While total knee arthroplasties (TKAs) are performed with the intent to reduce pain, chronic postsurgical pain (CPSP) is one of the most well-documented complications that can occur following surgery. This study aimed to assess whether perioperative factors, focusing on acute postsurgical pain and perioperative opioid consumption, were associated with the development of chronic postsurgical pain. Under general anesthesia, 108 patients underwent TKA and were treated postoperatively with a multimodal analgesia approach. Numeric Rating Scale (NRS) pain scores at rest and with movement were recorded on postoperative days 0–3, 7, 14, and 30. Patients were sent a survey to assess chronic pain at months 22–66, which was examined as a single-group post hoc analysis. Based on the responses, patients were either classified into the CPSP or non-CPSP patient group. Chronic postsurgical pain was defined as an NRS score ≥ 4 with movement and the presence of resting pain. The primary outcome was a change in NRS. There were no differences in NRS pain scores with movement in the first 30 days postoperatively between patients with CPSP and without CPSP. Each unit increase in resting pain on postoperative days 3 and 14 was associated with significantly greater odds of CPSP presence (OR = 1.52; OR = 1.61, respectively), with a trend towards greater odds of CPSP at days 7 and 30 (OR = 1.33; OR = 1.43, respectively). We found that very intense pain in the initial phase seems to be related to the development of CPSP after TKA.

Yuecheng Yang,1,2 Yunkui Zhang,1,2 Jun Zhang1,2 1Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, People’s Republic of China; 2Department of Oncology, Fudan University Shanghai Medical College, Shanghai, People’s Republic of ChinaCorrespondence: Jun Zhang, Department of Anesthesiology, Fudan University Shanghai Cancer Center, Dong-An Road No. 270, Shanghai, People’s Republic of China, Tel +86 021-64175590, Fax +86 021-6417477, Email snapzhang@aliyun.com

Usman Maqsood,1 Abdur Rehman,2 Saba Shafiq2 1Acute Medicine Department, Royal Stoke University Hospital, University Hospitals North Midlands, NHS Trust, Stoke-on-Trent, UK; 2Rawalpindi Medical University, Rawalpindi, Punjab, PakistanCorrespondence: Abdur Rehman, Rawalpindi Medical University, Tipu Road, Chamanzar Colony, Rawalpindi, Punjab, Pakistan, Tel +923340509801, Email dr.malik.ar123@gmail.com

While total knee arthroplasties (TKAs) are performed with the intent to reduce pain, chronic postsurgical pain (CPSP) is one of the most well-documented complications that can occur following surgery. This study aimed to assess whether perioperative factors, focusing on acute postsurgical pain and perioperative opioid consumption, were associated with the development of chronic postsurgical pain. Under general anesthesia, 108 patients underwent TKA and were treated postoperatively with a multimodal analgesia approach. Numeric Rating Scale (NRS) pain scores at rest and with movement were recorded on postoperative days 0–3, 7, 14, and 30. Patients were sent a survey to assess chronic pain at months 22–66, which was examined as a single-group post hoc analysis. Based on the responses, patients were either classified into the CPSP or non-CPSP patient group. Chronic postsurgical pain was defined as an NRS score ≥ 4 with movement and the presence of resting pain. The primary outcome was a change in NRS. There were no differences in NRS pain scores with movement in the first 30 days postoperatively between patients with CPSP and without CPSP. Each unit increase in resting pain on postoperative days 3 and 14 was associated with significantly greater odds of CPSP presence (OR = 1.52; OR = 1.61, respectively), with a trend towards greater odds of CPSP at days 7 and 30 (OR = 1.33; OR = 1.43, respectively). We found that very intense pain in the initial phase seems to be related to the development of CPSP after TKA. [ABSTRACT FROM AUTHOR]

Lowering opioid prescription doses and quantity decreases the risk of chronic opioid usage. A tool was inserted into the brief operative note for the surgeon to assess the severity of pain associated with the procedure. We studied surgeon adherence to current opioid-prescribing recommendations. Retrospective cohort study with 5486 patients were included in the study population. Each patient's prescription was scored yes or no for adherence on total morphine milligram equivalents (MMEs) and days prescribed with the selection in the brief operative note. The entire study population was tested for an increase from the null-hypothesis "benchmark" value of 75% using a one-sided exact binomial test of a single proportion with P < 0.05. This procedure was repeated for subgroups, with P < 0.01. Adherence to guidelines was higher than the 75% benchmark for "total MMEs prescribed" (79.5%; P < 0.001), but lower for "number of days prescribed" (63.5%; P > 0.999). Surgeries with severe predicted pain showed the highest adherence toward total MMEs prescribed at 87.1%, followed by moderate (80.5%) and mild (74.5%). Severe cases also showed the highest adherence in number of days prescribed (92.4%). Adherence to total MMEs prescribed was highest among attending physicians (88.1%) and lowest among residents/fellows (76.6%). Adherence to current guidelines was 79.5% for MMEs prescribed but only 63.5% for days prescribed. Compliance with guidelines was better for severe procedures than mild or moderate. Differences were seen across surgical departments. While an improvement from previous reports, further improvement is needed to reduce the number of days of opioids prescribed and increase compliance with recommended guidelines. [ABSTRACT FROM AUTHOR]

Purpose of Review: The care of patients with complex postsurgical pain can be challenging and burdensome for the healthcare system. Transitional pain service (TPS) is a relatively new concept and has not been widely adopted in the USA. This article explores the benefits and barriers of transitional pain services and describes the development of a TPS at our institution. Recent Findings: Evidence from a few institutions that have adopted TPS has shown decreased postsurgical opioid consumption for patients on chronic opioids and decreased incidence of chronic postsurgical opioid use for opioid-naïve patients. The development of a transitional pain service may improve outcomes for these complex patients by providing longitudinal and multidisciplinary perioperative pain care. Summary: In this article, we describe the implementation of a TPS at a tertiary medical center. Our TPS model involves a multidisciplinary team of anesthesiologists, pain psychologists, surgeons, and advanced practice providers. We provide longitudinal care, including preoperative education and optimization; perioperative multimodal analgesic care; and longitudinal follow-up for 90 days post-procedure. With our TPS service, we aim to reduce long-term opioid use and improve functional outcomes for our patients. [ABSTRACT FROM AUTHOR]

Background: Liposome bupivacaine (LB) is a long-acting anesthetic to enhance postoperative analgesia. Studies evaluating the efficacy of the LB against an active comparator (bupivacaine or placebo) on acute postoperative pain control in hemorrhoidectomy procedures are few and heterogeneous. Therefore, we performed a systematic review and meta-analysis comparing LB's analgesic efficacy and side effects to conventional/placebo anesthetic in hemorrhoidectomy patients. Methods: We performed a systematic review and meta-analysis of randomised controlled trials investigating the use of LB after haemorrhoidectomy. We searched the literature published from the time of inception of the datasets to August 19, 2022. The electronic databases included English publications in Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, and Scopus. Results: A total of 338 patients who underwent a hemorrhoidectomy procedure enrolled in three randomized clinical trials were included. The overall mean age was 45.84 years (SD ± 11.43), and there was a male predominance (53.55% male). In total 194 patients (52.2%) received LB and 144 (47.8%) received either bupivacaine or placebo. Pain scores at 72 h in the LB (199, 266, and 300 mg) were significantly lower than in the bupivacaine HCl group (p = 0.002). Compared to the bupivacaine/placebo group, the time to first use of opioids in the LB group was significantly longer at LB 199 mg (11 h vs. 9 h), LB 266 mg (19 h vs. 9 h), and LB 300 mg (19 h vs. 8 h) (p < 0.05). Moreover, compared to the bupivacaine/epinephrine group, it was significantly lower in the LB 266 mg group (3.7 vs. 10.2 mg) and at LB 300 mg (13 vs. 33 mg) (p < 0.05). Finally, regarding adverse effects, the conventional anesthetic/placebo group reported more pain in bowel movement than LB groups (OR 2.60, 95% CI 1.31–5.16). Conclusions: Comparing LB to conventional anesthetic/placebo anesthetic for hemorrhoidectomy, we found a statistically significant reduction in pain through 72 h, decreased opioid requirements, and delayed time to first opioid use. Moreover, the conventional anesthetic/placebo group reported more pain in bowel movement than LB groups. [ABSTRACT FROM AUTHOR]

The impact of the CD40-CD40L on the development of non-communicable neurological conditions is determined by abnormal CD40 expression and may be detrimental to nervous tissue function. Pain is one of the earliest psychophysical functions to develop. Postoperative complications causing pain should be addressed immediately. Regional analgesia techniques can speed up children's recovery and reduce the need for opioids. They can also lower the incidence of postoperative nausea and vomiting, respiratory complications, and postsurgical pain intensity. The aim of this study was to present a mathematical model that predicts changes in CD40-CD40L levels in children who underwent surgery under various analgesic modalities within the first five days postoperatively. The autoregressive probability model was used to predict the behavior of the experimental data function within 29 days after surgery. Material and Methods. The children were divided into three groups. Group I consisted of 33 children who underwent anterior abdominal wall surgery under general anesthesia with morphine. Group II comprised 27 children who underwent anterior abdominal wall surgery under general anesthesia with the transversalis fascia plane block (TFPB). Group III included 27 children who underwent anterior abdominal wall surgery under general anesthesia with the TFPB, combined with the quadratus lumborum block 4 (QLB-4) via a single injection. The serum CD40L levels were evaluated using the immunoenzymatic assay method. The autoregressive model method based on the Burg algorithm was used to predict the behavior of the experimental data function. To automate the calculation of predictions based on the Burg method, the 'predict' function in РТС MathCad Prime 7.0 software was used. All clinical and laboratory studies were conducted in accordance with the World Medical Association Declaration of Helsinki 'Ethical Principles for Medical Research Involving Human Subjects'. The study is a fragment of the research project of the Department of Children Diseases of Postgraduate Medical Education Faculty, Ivano-Frankivsk National Medical University «Health Status and Adaption of Children from the Precarpathian Region with Somatic Diseases, Their Prevention» 2021-2026, state registration number 0121U111129. Results. On the fifth day after surgery, the serum CD40-CD40L levels were highest in children who received conventional opioid analgesia. There was no significant difference observed between children in the TFPB and TFPB+QLB groups. On the 29th day after surgery, the predicted CD40-CD40L levels were lowest in children who received conventional opioid analgesia combined with the TFPB+QLB. Conclusions. The findings obtained confirmed the positive effect of combined analgesia using opioids and regional nerve block TFPB+QLB in children who received anterior abdominal surgery on suppressing immune mechanisms of pain syndrome involving the CD40-CD40L signaling system. [ABSTRACT FROM AUTHOR]

Background and Aims: Magnesium sulfate (MgSO4) has been demonstrated to have analgesic property in various clinical settings. This study explores if addition of MgSO4 to ropivacaine increases its analgesic efficacy when infiltrated continuously in the postsurgical wound following total abdominal hysterectomy. Material and Methods: This randomized controlled trial was conducted at a tertiary care referral hospital in New Delhi, India. Fifty-two patients were randomized into two groups to receive the intervention of which 48 were able to complete the study. The first group (n = 26) received 0.25% ropivacaine infiltration and the second group (n = 26) received 0.25% ropivacaine with 5% MgSO4 at the incision site for 48 h postoperatively. Primary objective was to compare the total postoperative opioid (morphine) consumption by the study participants in both the groups and the secondary objectives were pain scores at rest and at movement, patient satisfaction score, and wound quality of life on the 7th postoperative day among the two groups. Results: Both the groups were comparable in their demographic characteristics. The median morphine consumed at 48 h postoperatively was 16.5 [0-77] mg in the ropivacaine group and 13[1-45] mg in the ropivacaine with MgSO4 group and the difference was statistically insignificant (P = 0.788). There was no statistical difference between the groups with respect to the pain scores, patient satisfaction, or wound quality of life at 7 days. Conclusion: The addition of MgSO4 to ropivacaine does not confer any additional postoperative analgesic benefits over ropivacaine alone in continuous wound infiltration following total abdominal hysterectomy. [ABSTRACT FROM AUTHOR]

Background: There are several approaches for lumbar fusion, although there is yet to be a consensus on which approach is the best. This study aimed to evaluate the intraoperative blood loss and acute postoperative pain in single-level mini-open oblique lumbar interbody fusion (OLIF) versus open transforaminal lumbar interbody fusion (TLIF) surgeries for the degenerative spine. Methods: Thirty-two patients were assigned by the surgeon to OLIF or TLIF groups - 16 in mini-open OLIF and 16 in open TLIF groups. The intraoperative blood loss and postoperative hemoglobin, numerical rating scale (NRS) at proposed time intervals for 24 h postoperative, and rescue analgesics used were compared among the groups. The operative duration and hospital stay in both groups were also compared. Results: The OLIF group showed significantly higher postoperative hemoglobin (11.5 vs. 10.5 g %, P = 0.04), lower 24-h postoperative pain scores on movement, (NRS 4 vs. 5.5, P = 0.0001), and shorter hospital stay (4.5 vs. 7 days, P = 0.003) than TLIF group. However, the surgery duration was significantly longer in OLIF than in TLIF (190 vs. 150 min, P = 0.005). Intraoperative hemodynamics, other postoperative pain scores at variable time points, and rescue analgesics given were comparable among groups (P > 0.05). Intraoperative blood loss was lower in OLIF than TLIF (275 vs. 500 mL) but was not statistically significant (P > 0.05). Conclusion: Mini-open OLIF has favorable perioperative outcomes compared to open TLIF. Patients have higher postoperative hemoglobin and lesser pain on movement on the first postoperative day, leading to earlier mobilization and a shorter hospital stay. [ABSTRACT FROM AUTHOR]

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Chronic postoperative pain (also known as chronic postsurgical pain) is pain that occurs post-surgery and extends beyond the tissue-healing process, lasting for at least 3 months. Risk factors for the development of chronic postoperative pain include demographic/lifestyle, genetic, psychologic, and clinical factors (comorbidities, surgical factors, anesthesia/analgesia factors), as well as perioperative pain (preoperative and postoperative pain). In addition, there are several conditions that occur postoperatively leading to propagation of chronic postoperative pain, such as anterior cutaneous nerve entrapment, incisional neuromas, pudendal neuralgia, and ilioinguinal neuralgia. Clinicians should focus on identifying risk factors and mitigating them to decrease the incidence of chronic postoperative pain. (J GYNECOL SURG 39:262) [ABSTRACT FROM AUTHOR]

Background. The aim of the study was to assess changes in the serum CD40L level and its potential relationship with pain severity in children after anterior abdominal wall surgery on the background of general anaesthesia and its combination with various regional anaesthesia techniques. Materials and methods. The study included 87 children who underwent anterior abdominal wall surgery using different analgesic techniques. All children were divided into 3 groups: group I (n = 33) — general anaesthesia using morphine; group II (n = 27) — general anaesthesia with the transversalis fascia plane block (TFPB); group III (n = 27) — general anaesthesia using the TFPB combined with the quadratus lumborum block (QLB-4) via a single injection. Results. In group I, the mean serum level of CD40L two hours after surgery was 4,283 pg/ml, with a slight downward trend at discharge (Mann-Whitney U test = 52.5; р = 0.593). In group II, CD40L reduced significantly, by 25.3 % (U = 10.0; р = 0.002); 24 hours after surgery, it decreased by 15.1 % (U = 26.0; р = 0.20). At discharge, the level of CD40L in this group reduced significantly, by 54.4 % (U = 7.0; р = 0.003). In group III during all observation periods, the mean serum level of CD40L was 4–7.6 times lower (U = 0.0; р = 0.000) than corresponding levels in children of group II. Conclusions. The indicators of CD40L signaling were found to increase in paediatric anterior abdominal wall surgeries. There was a close positive correlation between postsurgical pain severity and CD40L serum levels. Single-injection TFPB + QLB-4 resulted in the lowest serum CD40L levels, an indicative of the lowest intensity of postsurgical pain.

Francisco Avila, Ricardo Torres-Guzman, Karla Maita, John P Garcia, Gioacchino D De Sario, Sahar Borna, Olivia A Ho, Antonio J Forte Division of Plastic Surgery, Department of Surgery, Mayo Clinic, Jacksonville, FL, USACorrespondence: Antonio J Forte, Mayo Clinic Florida, 4500 San Pablo Roads, Jacksonville, FL, 32224, USA, Tel +1 904-953-2073, Email ajvforte@yahoo.com.brAbstract: Postmastectomy pain syndrome (PMPS) is a common and debilitating form of postsurgical pain with neuropathic characteristics, presenting as burning, stabbing, or pulling sensations after mastectomy, lumpectomy, or other breast procedures. With a prevalence of 31%, the risk factors for PMPS include younger age, psychosocial factors, radiotherapy, axillary lymph node dissection, and a history of chronic pain. This review evaluates the pharmacological and surgical options for managing PMPS. Pharmacological treatment options include antidepressants, gabapentinoids, levetiracetam, capsaicin, and topical lidocaine. Procedural and surgical options include fat grafting, nerve blocks, radiofrequency ablation, peripheral nerve surgery, serratus plane block, and botulinum toxin injections. Despite the variety of therapeutic options available for patients, further randomized trials are required to conclude whether these treatments reduce the intensity of neuropathic pain in patients with PMPS. In particular, comparative studies and the inclusion of patients across a range of pain intensities will be essential to developing a treatment algorithm for PMPS. In conclusion, current management for these patients should be tailored to their individual requirements.Keywords: postmastectomy pain syndrome, postsurgical pain, neuropathic pain, neuralgia, breast neoplasms, Mastectomy

Background : There are several procedural variations for kidney transplant donors, including open, laparoscopic, hand-assisted, and robotic methods, with either an intra- abdominal or retroperitoneal approach. Conversely, fewer options are available for the recipient procedure. We introduce a method that involves a small incision, with the goal of being less invasive for recipients. Methods : Our current method was introduced in April 2022. As of July 2023, we have completed 27 cases. We analyzed several factors in these 27 cases, including the size of the incision, rewarming time, anastomosis time, graft function, analgesic use, and complications. Results : The average incision size was 73 mm. The time taken for anastomosis was 24. 1 minutes, while the rewarming time averaged 43.1 minutes. There were no instances of primary nonfunction. One case necessitated postoperative dialysis three times due to heart failure. Following stent removal, one patient developed grade 1 hydronephrosis. There was one instance of bleeding from the drain insertion site. Another case involved a clamp injury to the external iliac artery, which necessitated stent insertion on the fourth postoperative day. Compared to procedures performed using conventional methods, the use of analgesics was less in these cases. Conclusions: Our minimally invasive technique, which involves a small incision, is a feasible alternative that could potentially be less invasive than traditional methods.

Chronic pain has become a global health problem contributing to years lived with disability and reduced quality of life. Advances in the clinical management of chronic pain have been limited due to incomplete understanding of the multiple risk factors and molecular mechanisms that contribute to the development of chronic pain. The Acute to Chronic Pain Signatures (A2CPS) Program aims to characterize the predictive nature of biomarkers (brain imaging, high-throughput molecular screening techniques, or "omics," quantitative sensory testing, patient-reported outcome assessments and functional assessments) to identify individuals who will develop chronic pain following surgical intervention. The A2CPS is a multisite observational study investigating biomarkers and collective biosignatures (a combination of several individual biomarkers) that predict susceptibility or resilience to the development of chronic pain following knee arthroplasty and thoracic surgery. This manuscript provides an overview of data collection methods and procedures designed to standardize data collection across multiple clinical sites and institutions. Pain-related biomarkers are evaluated before surgery and up to 3 months after surgery for use as predictors of patient reported outcomes 6 months after surgery. The dataset from this prospective observational study will be available for researchers internal and external to the A2CPS Consortium to advance understanding of the transition from acute to chronic postsurgical pain.

Background: Parasternal intercostal blocks (PSB) have been proposed for postoperative analgesia in patients undergoing median sternotomy. PSB can be achieved using two different approaches, the superficial parasternal intercostal plane block (SPIP) and deep parasternal intercostal plane block (DPIP) respectively. Methods: We designed the present prospective, observational cohort study to compare the analgesic efficacy of the two approaches. Cardiac surgical patients who underwent full sternotomy from January to September 2022 were enrolled and divided into three groups, according to pain control strategy: morphine, SPIP, and DPIP group. Primary outcomes were was postoperative pain evaluated as absolute value of NRS at 12 h. Secondary outcomes were the NRS at 24 and 48 h, the need for salvage analgesia (both opioids and NSAIDs), incidence of postoperative nausea and vomiting, time to extubation, mechanical ventilation duration, and bowel disfunction. Results: Ninety-six were enrolled. There was no significant difference in terms of median Numeric Pain Rating Scale at 24 h and at 48 h between the study groups. Total postoperative morphine consumption was 1.00 (0.00–3.00), 2.00 (0.00–5.50), and 15.60 mg (9.60–30.00) in the SPIP, DPIP, and morphine group, respectively (SPIP and DPIP vs morphine: p < 0.001). Metoclopramide consumption was lower in SPIP and DPIP group compared with morphine group (p = 0.01). There was no difference in terms of duration of mechanical ventilation and of bowel activity between the study groups. Two pneumothorax occurred in the DPIP group. Conclusions: Both SPIP and DPIP seem able to guarantee an effective pain management in the postoperative phase of cardiac surgeries via full median sternotomy while ensuring a reduced consumption of opioids and antiemetic drugs. [ABSTRACT FROM AUTHOR]

The neural mechanisms for the persistence of pain after a technically successful arthroplasty in osteoarthritis (OA) remain minimally studied, and direct evidence of the brain as a predisposing factor for pain chronicity in this setting has not been investigated. We undertook this study as a first effort to identify presurgical brain and clinical markers of postarthroplasty pain in knee OA. Patients with knee OA (n = 81) awaiting total arthroplasty underwent clinical and psychological assessment and brain magnetic resonance imagining. Postoperative pain scores were measured at 6 months after surgery. Brain subcortical anatomic properties (volume and shape) and clinical indices were studied as determinants of postoperative pain. We show that presurgical subcortical volumes (bilateral amygdala, thalamus, and left hippocampus), together with shape deformations of the right anterior hippocampus and right amygdala, associate with pain persistence 6 months after surgery in OA. Longer pain duration, higher levels of presurgical anxiety, and the neuropathic character of pain were also prognostic of postsurgical pain outcome. Brain and clinical indices accounted for unique influences on postoperative pain. Our study demonstrates the presence of presurgical subcortical brain factors that relate to postsurgical persistence of OA pain. These preliminary results challenge the current dominant view that mechanisms of OA pain predominantly underlie local joint mechanisms, implying novel clinical management and treatment strategies. [ABSTRACT FROM AUTHOR]

Acute pain after breast surgery decreases the quality of life of cancer survivors. Previous studies using a variety of definitions and methods report prevalence rates between 10% and 80%, which suggests the need for a comprehensive framework that can be used to guide assessment of acute pain and pain-related outcomes after breast surgery. A multidisciplinary task force with clinical and research expertise performed a focused review and synthesis and applied the 5 dimensional framework of the AAAPT (Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks [ACTTION], American Academy of Pain Medicine [AAPM], American Pain Society [APS] Pain Taxonomy) to acute pain after breast surgery. Application of the AAAPT taxonomy yielded the following: 1) Core Criteria: Location, timing, severity, and impact of breast surgery pain were defined; 2) Common Features: Character and expected trajectories were established in relevant surgical subgroups, and common pain assessment tools for acute breast surgery pain identified; 3) Modulating Factors: Biological, psychological, and social factors that modulate interindividual variability were delineated; 4) Impact/Functional Consequences: Domains of impact were outlined and defined; 5) Neurobiologic Mechanisms: Putative mechanisms were specified ranging from nerve injury, inflammation, peripheral and central sensitization, to affective and social processing of pain. PERSPECTIVE: The AAAPT provides a framework to define and guide improved assessment of acute pain after breast surgery, which will enhance generalizability of results across studies and facilitate meta-analyses and studies of interindividual variation, and underlying mechanism. It will allow researchers and clinicians to better compare between treatments, across institutions, and with other types of acute pain.

This review is a literature review based on articles gathered over the previous 10 years from scientific search engines. To divide pain management following total joint arthroplasty into segments. The pain is frequently connected with incision pain induced by surgical damage to a major peripheral nerve and differs in quality and location from pain experienced before surgery. Acetaminophen, nonsteroidal anti-inflammatory drugs, and opioid analgesia are the three categories of medicines used to manage postsurgical pain. These medications can be used as pre-emptive analgesia or as part of a multimodal analgesia regimen. Multimodal analgesia is the most common therapy for postoperative pain following joint replacement. This medication is meant to lessen the risk of negative effects that may arise after taking opioids.

Naoki Aoyama, Masashi Izumi, Toru Morimoto, Hiroyuki Wada, Junpei Dan, Yusuke Kasai, Yoshinori Satake, Koji Aso, Masahiko Ikeuchi Department of Orthopedic Surgery, Kochi Medical School, Kochi University, Nankoku, JapanCorrespondence: Masashi Izumi, Department of Orthopedic Surgery, Kochi Medical School, Kochi University, 185-1 Oko-cho Kohasu, Nankoku, 783-8505, Japan, Tel +81-88-880-2386, Fax +81-88-880-2388, Email izumim@kochi-u.ac.jpPurpose: The mechanisms underlying chronic postsurgical pain after joint replacement (JR) are complex, and it has been suggested that chronic postsurgical pain can develop as a result of inadequate acute pain management. Few studies have addressed acute pain after JR using specific animal models. This study aimed to develop a novel JR model focused on postsurgical pain assessment and the time course of pain recovery.Materials and Methods: Rats were allocated to the following three groups: sham (joint exposure), joint destruction (JD; resection of the femoral head), and JR (femoral head replacement using an originally developed implant). The time course of postsurgical pain behavior was measured using a dynamic weight-bearing apparatus, along with radiological assessments. The expression of calcitonin gene-related peptide-immunoreactive (CGRP-IR) neurons in the dorsal root ganglion (DRG) was evaluated by immunohistochemistry on days 28 and 42.Results: The ratio of weight-bearing distribution in the JR group gradually recovered from day 14 and reached the same level as that in the sham group on day 42, which was significantly greater than that in the JD group after day 7 (p< 0.05). Radiologically, no significant issues were found, except for transient central migration of the implant in the JR group. The percentage of CGRP-IR DRG neurons in the JR group was significantly lower than that in the JD group on day 28 (mean, 37.4 vs 58.1%, p< 0.05) and day 42 (mean, 32.3 vs 50.0%, p< 0.05).Conclusion: Our novel JR model presented acute postsurgical pain behavior that was successfully recovered to the baseline level at day 42 after surgery. Difference of the pain manifestation between the JR and JD groups could be supported by the expression of CGRP-IR in DRG neurons. This model is the first step toward understanding detailed mechanisms of post-JR pain.Keywords: joint replacement, postsurgical pain, dynamic weight bearing, CGRP

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Anxiety contributes to postsurgical pain, and midazolam is frequently prescribed preoperatively. Conflicting results have been described concerning the impact of midazolam on pain. This study aims to evaluate the effect of systemic midazolam on pain after open inguinal hernia repair, clarifying its relationship with preoperative anxiety. A prospective observational cohort study was conducted in three Portuguese ambulatory units between September 2018 and March 2020. Variable doses of midazolam were administered. Postsurgical pain was evaluated up to three months after surgery. We enrolled 306 patients and analyzed 281 patients. The mean preoperative anxiety Numeric Rating Scale score was 4 (3) and the mean Surgical Fear Questionnaire score was 22 (16); the mean midazolam dose was 1.7 (1.1) mg with no correlation to preoperative anxiety scores. Pain ≥4 was present in 67% of patients 24 h after surgery and in 54% at seven days; at three months, 27% were classified as having chronic postsurgical pain. Preoperative anxiety correlated to pain severity at all time points. In multivariable regression, higher midazolam doses were associated with less pain during the first week, with no apparent effect on chronic pain. However, subgroup analyses uncovered an effect modification according to preoperative anxiety: the decrease in acute pain occurred in the low-anxiety patients with no effect on the high-anxiety group. Inversely, there was an increase in chronic postsurgical pain in the very anxious patients, without any effect on the low-anxiety group. Midazolam, generally used as an anxiolytic, might impact distinctively on pain depending on anxiety. [ABSTRACT FROM AUTHOR]

Persistent arm pain is a common problem after breast cancer surgery. Little is known about genetic factors that contribute to this type of postsurgical pain. Study purpose was to explore associations between persistent arm pain phenotypes and genetic polymorphisms among 15 genes involved in catecholaminergic and serotonergic neurotransmission. Women (n = 398) rated the presence and intensity of arm pain monthly for 6 months after breast cancer surgery. Three distinct latent classes of patients were identified (ie, no arm pain [41.6%], mild arm pain (23.6%), and moderate arm pain (34.8%). Logistic regression analyses were used to evaluate for differences between genotype or haplotype frequencies and the persistent arm pain classes. Compared with the no arm pain class, 3 single nucleotide polymorphisms and 1 haplotype, in 4 genes, were associated with membership in the mild arm pain class: COMT rs4633, HTR2A haplotype B02 (composed of rs1923886 and rs7330636), HTR3A rs1985242, and TH rs2070762. Compared with the no arm pain class, 4 single nucleotide polymorphisms in 3 genes were associated with membership in the moderate arm pain class: COMT rs165656, HTR2A rs2770298 and rs9534511, and HTR3A rs1985242. Findings suggest that variations in catecholaminergic and serotonergic genes play a role in the development of persistent arm pain. PERSPECTIVE: Limited information is available on genetic factors that contribute to persistent arm pain after breast cancer surgery. Genetic polymorphisms in genes involved in catecholaminergic and serotonergic neurotransmission were associated with 2 persistent arm pain phenotypes. Findings may be used to identify patients are higher risk for this common pain condition.

Orthopedic trauma is a significant military problem, causing several of the most disabling conditions with high rates of separation from duty and erosion of military readiness. The objective of this report is to summarize the findings of case series of a non-opioid therapy-percutaneous peripheral nerve stimulation (PNS) - and describe its potential for postoperative analgesia, early opioid cessation, and improved function following orthopedic trauma. Percutaneous PNS has been evaluated for the treatment of multiple types of pain, including two case series on postoperative pain following total knee replacement (n = 10 and 8, respectively) and a case series on postamputation pain (n = 9). The orthopedic trauma induced during TKR is highly representative of multiple types of orthopedic trauma sustained by Service members and frequently produces intense, prolonged postoperative pain and extended opioid use following surgery. Collectively, the results of these three clinical studies demonstrated that percutaneous PNS can provide substantial pain relief, reduce opioid use, and improve function. These outcomes suggest that there is substantial potential for the use of percutaneous PNS following orthopedic trauma.

ObjectivesNumbness associated with neuropathic pain suggests the loss of function in myelinated, large diameter sensory neurons. The purpose of this study was to examine the relationships between pain severity and subjective (ie, severity of numbness) and objective (ie, loss of light touch sensations, vibration thresholds) measures of loss of large fiber function in adult survivors with chemotherapy-induced peripheral neuropathy (CIPN, n=426) and breast cancer patients with persistent postsurgical pain (n=80).Material and methodsFor both samples, average pain and numbness were evaluated using a 0 to 10 numeric rating scale. Loss of light touch sensations in the hands and feet of patients with CIPN and in the upper arm of patients at 5 and 6 months following breast cancer surgery were assessed using Semmes Weinstein monofilaments. Loss of vibration in the hands and feet of patients with CIPN was assessed using a biothesiometer. Pearson Product Moment correlation coefficients were calculated between average pain and the number or percentage of sites with loss of light touch sensations, mean vibration thresholds, and the severity of numbness.ResultsFor both pain conditions, average pain scores were significantly correlated with objective measures of large fiber function (r=0.12 to 0.34; all P

Abstract Background Myofascial pain syndrome is one of the causes of prolonged postoperative pain after abdominal surgery. However, diagnosis and treatment of myofascial pain syndrome, especially its myofascial trigger point (MTrP), have not been well established. Case presentation A 55-year-old man experienced severe subacute abdominal pain after laparoscopic hepatectomy despite aggressive postoperative pain management. He had a positive Carnett’s sign, indicating abdominal wall pain, 2 weeks after the surgery. Ultrasonography showed a hyperechoic spot surrounded by a hypoechoic area in the inner abdominal oblique muscle under the palpable spot that fulfills the criteria of MTrP. The echogenic MTrP disappeared after repetitive ultrasound-guided trigger point injections (USG TPIs) with pain relief. Conclusions Our present case indicates that diagnosing myofascial pain by visualizing the echogenic MTrPs in the abdominal muscles, and subsequent USG TPIs, might provide an accurate maneuver for diagnosis and treatment of subacute myofascial pain after abdominal surgery.

Abstract: To have a complete understanding of an experimental analgesic's efficacy in treating acute postoperative pain, it is necessary to understand its effect on both hard-tissue pain and soft-tissue pain. For this reason, regulatory bodies including the U.S. Food and Drug Administration and European EMA typically require drug developers to demonstrate efficacy in both hard-tissue and soft-tissue pain to grant a broad approval for an analgesic in acute postoperative pain. Hard-tissue models such as bunionectomy and molar extraction are well-validated and efficient with long histories in clinical trials, but until recently, a similarly well-standardized and fast-enrolling soft-tissue model was not available. Abdominoplasty was developed as an acute postoperative pain model and introduced to the clinical trial marketplace in 2014 to address the need for a viable soft-tissue model. Since then, at least 13 industry-sponsored studies, including multiple pivotal trials, have been conducted, providing a data set that can be used to interrogate the model's strengths and weaknesses. The authors outline the development history of abdominoplasty, discuss key clinical and design characteristics of the model, and review public data from abdominoplasty acute pain studies available to date. The data suggest that abdominoplasty is a well-validated soft-tissue surgical model that provides high-quality experimental outputs, enabling the efficacy of investigational analgesics in soft-tissue pain to be understood successfully. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The duration of postsurgical pain is closely correlated with perioperative stress. Most patients suffer short-term sleep disorder/deprivation before and/or after surgery, which leads to extended postsurgical pain by an undetermined mechanism. The paraventricular thalamus (PVT) is a critical area that contributes to the regulation of feeding, awakening, and emotional states. However, whether the middle PVT is involved in postoperative pain or the extension of postoperative pain caused by perioperative sleep deprivation has not yet been investigated. Methods: We established a model of postoperative pain by plantar incision with perioperative rapid eye movement sleep deprivation (REMSD) 6 h/day for 3 consecutive days in mice. The excitability of the CaMKIIα+ neurons in the middle PVT (mPVTCaMKIIα) was detected by immunofluorescence and fiber photometry. The activation/inhibition of mPVTCaMKIIα neurons was conducted by chemogenetics. Results: REMSD prolonged the duration of postsurgical pain and increased the excitability of mPVTCaMKIIα neurons. In addition, mPVTCaMKIIα neurons showed increased excitability in response to nociceptive stimuli or painful conditions. However, REMSD did not delay postsurgical pain recovery following the ablation of CaMKIIα neurons in the mPVT. The activation of mPVTCaMKIIα neurons prolonged the duration of postsurgical pain and elicited anxietylike behaviors. In contrast, inhibition of mPVTCaMKIIα neurons reduced the postsurgical pain after REMSD. Conclusion: Our data revealed that the CaMKIIa neurons in the mPVT are involved in the extension of the postsurgical pain duration induced by REMSD, and represented a novel potential target to treat postoperative pain induced by REMSD. [ABSTRACT FROM AUTHOR]

Ruoyao Xu,1 Jie Wang,1 Huimin Nie,1 Danyi Zeng,1 Chengyu Yin,1 Yuanyuan Li,1 Huina Wei,1 Boyu Liu,1 Yan Tai,2 Qimiao Hu,1 Xiaomei Shao,1 Jianqiao Fang,1 Boyi Liu1 1Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou, 310053, People’s Republic of China; 2Academy of Chinese Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, 310053, People’s Republic of ChinaCorrespondence: Boyi Liu; Jianqiao Fang, Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou, 310053, People’s Republic of China, Email boyi.liu@foxmail.com; fangjianqiao7532@163.comBackground: Chronic postsurgical pain (CPSP) is common among patients receiving major surgeries. CPSP produces suffering in patients, both physically and mentally. However, the mechanisms underlying CPSP remain elusive. Here, a genome-wide expression profiling of ipsilateral spinal cord dorsal horn (SCDH) was performed to identify potential genes related with CPSP.Methods: A rat skin/muscle incision and retraction (SMIR) model was established to induce CPSP. Immunostaining was used to study glial cell and neuron activation in ipsilateral SCDH of SMIR model rats. RNA sequencing (RNA-Seq), combined with bioinformatics analysis, was undertaken to explore gene expression profiles. qPCR was applied to validate the expression of some representative genes.Results: The SMIR model rats developed persistent mechanical allodynia in ipsilateral hindpaw for up to 14 days. Ipsilateral SCDH of SMIR rats showed remarkable glial cell and neuron activation. A number of differentially expressed genes (DEGs) were identified in ipsilateral SCDH of SMIR rats by RNA-Seq. qPCR confirmed expression of some representative DEGs. Bioinformatics indicated that chemical synaptic transmission, sensory perception of pain and neuroactive ligand-receptor interaction were predominant functions. We compared our dataset with human pain-related genes and found that several genes exclusively participate in pain modulation and mechanisms.Conclusion: Our study provided novel understandings of the molecular mechanisms possibly contributing to CPSP. These findings may offer new targets for future treatment of CPSP.Keywords: postsurgical pain, spinal cord dorsal horn, RNA-Seq, microglia, genome

Some patients with postoperative hip fractures (HF) experience persistent severe pain. In this longitudinal study, we examined the characteristics of patients with persistent pain after HF surgery, and the factors influencing pain intensity.We conducted an 8-week prospective study in patients with postsurgical HF. Verbal rating scale (VRS), and multifaceted outcomes, including pressure pain threshold (PPT) (affected site and biceps), were evaluated at 2, 4, and 8 weeks postoperatively. Patients were divided into mild (VRS ≤1) and severe (VRS ≥2) groups according to pain intensity at 8 weeks postoperatively. Statistical analyses were performed using two-way ANOVA and decision-tree analysis.VRS, PPT at the affected site and biceps, and physical activity (PA) time were significantly lower in the severe group than in the mild group 2 weeks postoperatively. VRS, PPT at the affected site, pain catastrophizing (PCS)-13, and the Tampa Scale for Kineshiophobia (TSK)-11 did not show significant improvements in the severe group. Decision tree analysis revealed that the VRS and PCS-13 at 4 weeks, PA time at 2 weeks, and TSK-11 change between 4 weeks and 2 weeks were factors influencing severe pain intensity at 8 weeks after HF surgery.Persistent severe pain after HF surgery was characterised by high peripheral and central sensitisation, pain catastrophizing, and reduced PA at 2 weeks after HF surgery. In addition, early pain intensity, pain catastrophizing, and PA may be hierarchically influential factors for persistent pain 8 weeks after HF surgery. [ABSTRACT FROM AUTHOR]

Christopher K Cheung, Janet O Adeola, Sascha S Beutler, Richard D Urman Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USACorrespondence: Richard D UrmanDepartment of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School, 75 Francis Street, CWN L1, Boston, MA, 02115, USATel +1 617 732 8210Fax +1 617 264 6841Email rurman@bwh.harvard.eduAbstract: Postoperative pain is a common but often inadequately treated condition. Enhanced recovery pathways (ERPs) are increasingly being utilized to standardize perioperative care and improve outcomes. ERPs employ multimodal postoperative pain management strategies that minimize opioid use and promote recovery. While traditional opioid medications continue to play an important role in the treatment of postoperative pain, ERPs also rely on a wide range of non-opioid pharmacologic therapies as well as regional anesthesia techniques to manage pain in the postoperative setting. The evidence for the use of these interventions continues to evolve rapidly given the increasing focus on enhanced postoperative recovery. This article reviews the current evidence and knowledge gaps pertaining to commonly utilized modalities for postoperative pain management in ERPs.Keywords: enhanced recovery after surgery, ERAS, multimodal analgesia, opioid-sparing analgesia, postsurgical pain, pain management

BackgroundOpen hemorrhoidectomy is one of the standard procedures for grade IV hemorrhoids. Postsurgical pain is a common problem for patients. We aim to prospectively evaluate potential factors affecting postoperative pain among hemorrhoidectomy patients.MethodsAn observational study was conducted on 360 patients who had undergone Milligan-Morgan open hemorrhoidectomy. Details of the surgery and baseline information were recorded. Preoperative anxiety and depression were analyzed via the self-rating anxiety scale 20 (SAS-20) and self-rating depression scales 20 (SDS-20), respectively. Postoperative pain score was performed daily after surgery until the patient was discharged. The numerical pain score was evaluated by the visual analogue scale (VAS). The association between preoperative psychological states (anxiety or depression) and postoperative pain was analyzed using a generalized additive mixed model.ResultsA total of 340 patients eventually provided complete data and were included in our study. The average age was 43.3 ± 14.4 years, and 62.1% of patients were women. In total, 14.9% of patients had presurgical anxiety and 47.1% had presurgical depression. Postsurgical pain reached a peak point 1–2 days after surgery and went down to a very low level around 4–5 days after surgery. More excision of hemorrhoids could lead to more pain experience after surgery. Presurgical depression was associated with postsurgical pain. Patients who had presurgical depression had higher pain scores after surgery (2.3 ± 1.9 vs. 3.3 ± 1.9, p = 0.025).ConclusionPreoperative depression and the amount of excisional hemorrhoids are positively related to postsurgical pain.

ABSTRACTBackground Chronic postsurgical pain (CPSP) may increase the risk of postoperative cognitive dysfunction (POCD) directly or by negatively impacting mobility. A comprehensive measure of satisfaction with surgery that accounts for ability to perform activities might be even more strongly associated with POCD. There might be complex mechanisms underlying the interplays between postoperative pain and cognition.Aims The primary objective is to explore whether CPSP at 6 months is associated with POCD (≥2-point decline in the Montreal Cognitive Assessment [MoCA] compared to preoperative) at 12 months. Secondary objectives are to explore the association between satisfaction with surgery and POCD, the role of pain medications (opioids) in the association between CPSP and POCD, the role of patient preoccupation/optimism and coping in determining the effect of pain on cognition, and the hypothesis of neurogenesis interference as an underlying mechanism.Methods We will prospectively recruit ≥100 patients ≥50 years old undergoing elective total knee/hip arthroplasty. Sociodemographic characteristics, comorbidities, frailty, pain, and pain medications will be assessed preoperatively. The Somatic Preoccupation and Coping questionnaire will be administered preoperatively and 4 to 6 weeks postoperative. Pain and the Self-Administered Patient Satisfaction Scale will be measured at 3 and 6 months. MoCA and neuropsychological tests will be administered at baseline, 4 to 6 weeks, and 6 and 12 months. Blood will be longitudinally collected for biomarker analysis.Progress Forty-six participants have been enrolled in the study so far.Conclusion ArthroCaP will provide preliminary data on the association of CPSP and patient satisfaction with POCD and underlying mechanisms. It will inform larger confirmatory and interventional studies to enhance the benefits of surgery.

Persistent pain after posterior spinal fusion affects 12 to 42% of patients with adolescent idiopathic scoliosis. The incidence of persistent pain among surgically treated children with Scheuermann kyphosis and spondylolisthesis is not known. The aim of our study was to determine the predictors and incidence of acute and chronic postoperative pain in adolescents undergoing posterior spinal fusion surgery. The study was a retrospective analysis of a prospectively collected pediatric spine register data. The study included 213 consecutive patients (158 AIS, 19 Scheuermann kyphosis, and 36 spondylolisthesis), aged 10–21 years undergoing posterior spinal fusion at a university hospital between March 2010 and March 2020. The mean (SD) daily postoperative opioid consumption per kilogram was significantly lower in the spondylolisthesis patients 0.36 mg/kg/day (0.17) compared to adolescent idiopathic scoliosis 0.51 mg/kg/day (0.25), and Scheuermann kyphosis 0.52 mg/kg/day (0.25) patients after surgery (p = 0.0004). Number of levels fused correlated with the daily opioid consumption (rs = 0.20, p = 0.0082). The SRS-24 pain domain scores showed a statistically significant improvement from preoperative levels to two-year follow-up in all three groups (p ≤ 0.03 for all comparisons). The spondylolisthesis patients had the lowest SRS pain domain scores (mean 4.04, SD 0.94), reporting more pain two years after surgery, in comparison to AIS (mean 4.31, SD 0.60) (p = 0.043) and SK (mean 4.43, SD 0.48) patients (p = 0.049). Persistent postoperative pain in adolescents undergoing posterior spinal fusion is related to disease pathology while higher acute postoperative pain is associated with a more extensive surgery. Spondylolisthesis patients report more chronic pain after surgery compared to AIS and SK patients. [ABSTRACT FROM AUTHOR]