Incidence Of Chronic Postoperative Pain Research Articles

The Role of Intravenous Lidocaine in Preventing Chronic Post-Operative Pain

Background and Goal of Study Chronic post-operative pain (CPOP) is an increasing public health issue considering its impact on the patients quality of life and and the associated costs for the healthcare system. The incidence of CPOP can be as high as 75%, depending on the surgical procedure and other factors. Lidocaine is a local anesthetic with anti-inflammatory, analgesic and antihyperalgesic properties. Several studies have shown its use in controlling acute post-operative pain when used intravenously. The goal of this study was to define the role of intravenous lidocaine in preventing CPOP. Materials and Methods The PubMed database was searched from 2006 and 2019 with the keywords: “Chronic post-operative pain” or “Chronic post-surgical pain” or “Chronic pain” and “Intravenous lidocaine”. Adequate papers for the purpose of this study were selected. Results and Discussion Three randomized controlled trials that met criteria were obtained: two on breast surgery and the other on open nephrectomy. All trials used intravenous lidocaine during surgery, suspending the infusion up to the first 24-hours of the post-operative period. All three of them showed a significant decrease on the incidence of CPOP. There was a 20-fold decrease six months after breast surgery. Conclusion Intravenous lidocaine seems to decrease the incidence of CPOP however, there is limited evidence. More trials are necessary to define the efficacy and safety of intravenous lidocaine. A generally accepted definition of CPOP is needed.

Circulating long non-coding RNA signature in knee osteoarthritis patients with postoperative pain one-year after total knee replacement.

The incidence of chronic postoperative pain after total knee replacement (TKR) is approx. 20%, and hence preoperative risk factors are important to identify. Recent studies have indicated that preoperative inflammatory markers might hold prognostic information for the development of chronic postoperative pain. Long non-coding RNA (lncRNA) regulates the expression of genes related to e.g. inflammatory processes. The current study aimed to investigate the preoperative lncRNA signature as possible preoperative predictive markers for chronic postoperative pain following TKR. Serum samples, collected preoperatively from 20 knee osteoarthritis (KOA) patients, were analyzed for 84 validated circulatory lncRNA. Pain intensity was assessed using a visual analog scale (VAS) before and one-year after TKR. Differences for the lncRNA expression were analyzed between patients with chronic postoperative pain (VAS≥3) and those with a normal postoperative recovery (VAS<3). LncRNA Myeloid Zinc Finger 1 Antisense RNA 1 (MZF1-AS1) (fold change-3.99; p-value: 0.038) (shown to be involved neuropathic pain) Metastasis associated lung adenocarcinoma transcript 1 (MALAT1) (fold change-3.39; p-value: 0.044) (shown to be involved neuropathic pain); Patched 1 pseudogene (LOC100287846) (fold change-6.99; p-value: 0.029) (unknown in pain) were down-regulated preoperatively in the group with chronic postoperative pain compared to the group normal postoperative pain recovery. These findings suggest, that TKR patients with chronic postoperative pain present preoperative downregulations of three specific lncRNA detectable at thesystemic level. The presented study might give new insights into the complexity of chronic postoperative pain development and show how non-coding RNA plays a role in the underlying molecular mechanisms of pain.

Opioid-Free Anesthesia Benefit-Risk Balance: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Opioid-free anesthesia (OFA) is used in surgery to avoid opioid-related side effects. However, uncertainty exists in the balance between OFA benefits and risks. We searched for randomized controlled trials (RCTs) comparing OFA to opioid-based anesthesia (OBA) in five international databases. The co-primary outcomes were postoperative acute pain and morphine consumption at 2, 24, and 48 h. The secondary outcomes were the incidence of postoperative chronic pain, hemodynamic tolerance, severe adverse effects, opioid-related adverse effects, and specific adverse effects related to substitution drugs. Overall, 33 RCTs including 2209 participants were assessed. At 2 h, the OFA groups had lower pain scores at rest MD (0.75 (−1.18; −0.32)), which did not definitively reach MCID. Less morphine was required in the OFA groups at 2 and 24 h, but with very small reductions: 1.61 mg (−2.69; −0.53) and −1.73 mg (p < 0.05), respectively, both not reaching MCID. The reduction in PONV in the OFA group in the PACU presented an RR of 0.46 (0.38, 0.56) and an RR of 0.34 (0.21; 0.56), respectively. Less sedation and shivering were observed in the OFA groups with an SMD of −0.81 (−1.05; −0.58) and an RR of 0.48 (0.33; 0.70), respectively. Quantitative analysis did not reveal differences between the hemodynamic outcomes, although severe side effects have been identified in the literature. No clinically significant benefits were observed with OFA in terms of pain and opioid use after surgery. A clear benefit of OFA use was observed with respect to a reduction in PONV. However, more data on the safe use of OFAs should be collected and caution should be taken in the development of OFA.

A retrospective analysis of the effects of different analgesics on the pain of patients with traumatic thoracolumbar fractures in the peri-treatment period

ObjectiveTo analyze and compare the effects of peri-treatment analgesics on acute and chronic pain and postoperative functional recovery of patients with thoracolumbar fractures, so as to guide the clinical drug use.MethodsSeven hundred nineteen patients with thoracolumbar fractures were collected and divided into acetaminophen dihydrocodeine, celecoxib, and etoricoxib groups. The main indicators were the degree of postoperative pain (visual analog scale (VAS)), the incidence of chronic pain and postoperative functional recovery (Oswestry dysfunction index (ODI) and Japanese Orthopedics Association score (JOA)), which were continuously tracked through long-term telephone follow-up. The correlation analysis of ODI-pain score, peri-treatment VAS score, and ODI index was performed, and bivariate regression analysis was conducted to understand the risk factors for chronic pain.ResultsRegression analysis showed that severe spinal cord injury and peri-treatment use of acetaminophen dihydrocodeine were both one of the risk factors for postoperative chronic pain. But there were no statistically conspicuous differences in basic characteristics, preoperative injury, and intraoperative conditions. Compared with the other two groups, patients in the acetaminophen dihydrocodeine group had longer peri-therapeutic analgesic use, higher pain-related scores (VAS 1 day preoperatively, VAS 1 month postoperatively, and ODI-pain 1 year postoperatively), higher VAS variation, higher incidence of chronic pain 1 year after surgery, and higher ODI index. And other ODI items and JOA assessments showed no statistically significant differences. In addition, the correlation analysis showed that the peri-treatment pain score was correlated with the severity of postoperative chronic pain.ConclusionAlthough the peri-treatment analgesic effect of acetaminophen dihydrocodeine is good, it is still necessary to combine analgesics with different mechanisms of action for patients with severe preoperative pain of thoracolumbar fracture, so as to inhibit the incidence of postoperative chronic pain and improve the quality of postoperative rehabilitation.

Meta-analysis of mesh-plug repair and Lichtenstein repair in the treatment of primary inguinal hernia.

The present study systematically evaluated the clinical effects of mesh-plug and Lichtenstein herniorrhaphy in the treatment of primary inguinal hernia. PubMed, Embase, and the Cochrane Library (cut-off: May 25, 2020) databases were searched to select randomized controlled trials (RCTs) on mesh-plug and Lichtenstein herniorrhaphy for the treatment of primary inguinal hernia. Articles that met the inclusion criteria were screened and evaluated for quality. RevMan 5.3 software was used to perform a meta-analysis of operation time, discomfort in the inguinal region, haematoma, seroma, infection, time to return to normal activities, incidence of postoperative chronic pain, and recurrence rate. Eleven RCTs with 1457 patients in the mesh-plug group and 1472 in the Lichtenstein group were included. Meta-analysis showed that the mesh-plug herniorrhaphy group had a shorter operation time than the Lichtenstein herniorrhaphy group [P < 0.0001] but a longer time to return to normal activities after surgery [MD = 1.48, 95% CI (0.58, 2.38), P = 0.001]. There were no significant differences in postoperative discomfort in the inguinal region [P = 0.90], seroma [P = 0.10], haematoma [P = 0.27], infection [P = 0.40], incidence of postoperative chronic pain [P = 0.90], or recurrence rate [P = 0.77] between groups. Mesh-plug herniorrhaphy requires a shorter operation time than Lichtenstein herniorrhaphy, and there is no significant difference in postoperative complications or recurrence rate between the two methods. Clinical trial registration: INPLASY202070088. Meta-analysis of mesh -plug repair and Lichtenstein repair in the treatment of primary inguinal hernia.

Evaluation of Trans Rectus Sheath Extra-Peritoneal Mesh Repair:Our Early Results

Background:An inguinal hernia is a protrusion of the content of the abdominal cavity or preperitoneal fat through a hernia defect in the inguinal area.Inguinal hernia repair is considered one of the most common surgical procedures done all over the world. The Lichtenstein technique, introduced in 1984, is the best evaluated and the most common open tensionless mesh repair of different open mesh techniques with low morbidity and low recurrence rates (≤4%) in the long-term follow-up. Objectives:Evaluation of our results ofTrans Rectus Sheath Extra-Peritoneal Procedure (TREPP)considering the data available from the literature of the standard Lichtenstein method for the treatment of primary adult inguinal hernia. Patients and Methods: A clinical study was conducted at Qena University Hospital over 6 months period, between 1/9/2019 to 1/3/2020 for patients with hernia visiting the outpatient clinic. We operated on 52 patients using the TREPP technique with a follow-up period at 6 months duration post-operative. Results:We operated on 52 patients using the TREPP technique; all of them were males with a mean age of 33.3±10.2years. Intra-operative complications occurred in 1.9% of cases. No cases showed recurrence during the first 6 months post-operative. No cases had CPIP (chronic post-operative pain). Conclusion: The TREPP technique is a good alternative to the standard Lichtenstein tension-free mesh repair with a low recurrence rate as in Lichtenstein repair, but with a less incidence of CPIP and scrotal edema with shorter operation time.

Comparison of Incident of Chronic Pain Post Operations of Preperitoneal Transabdominal Herniorafi Laparoscopy (TAPP) and Totally Extraperitoneal (TEP) in General Hospital Dr. M. Djamil Padang

A B S T R A C TIntroduction : Inguinal herniation is a protrusion of peritoneal component throughabdominal wall caused by the weakness of aponeurotica tissue of abdomen. Inguinalherniation is the most common herniation cases in which 291.145 patient registeredin Indonesia at 2012 and 87 patients in General Government Hospital of M. DjamilPadang at 2017-2018. Herniation treatment is consisted of herniorrhapylaparoscopy using the TEP or TAPP techniques and both of them are related to theincidence of chronical post-operative pain that was defined by IASP as anuncomfortable sensation lasting for more than 3 months. Method: This researchwas using retrospective study design. The research was conducted at RSUP Dr. M.Djamil Padang in August – October 2020 with 54 samples. Result: The study foundthere was 54 cases of inguinal herniation fit to the inclusion criteria with peak ageof 82 years old and average of 59.1 years old. Most patients were male (79.62 %).There were 2 patients having chronic pain (7.41%) after herniorrhapy using the TAPPtechnique and 1 more (3.71%) having chronic pain with TEP technique. Bivariateanalysis was done by Fisher Exact Test and the study concluded there was nostatistical significance in relationship of chronic post-operative pain incidence withthe particular technique chosen at herniorrhapy laparoscopy (p=1.000). Conclusion:There was no significant relationship between the incidence of postoperative chronicpain in patients undergoing laparascopic hernioraphy and TEP or TAPP procedure.

Tratamiento laparoscópico de la hernia inguinal por técnica transabdominal preperitoneal. Análisis retrospectivo de una serie de casos

El objetivo del presente trabajo es reportar y analizar nuestra experiencia con la técnica endoscópica transabdominal preperitoneal (TAPP) en el tratamiento de la hernia inguinal. Métodos: Estudio retrospectivo mediante la revisión de nuestra base de datos electrónica y las historias clínicas en físico de la Clínica Santa Sofía, de los pacientes con diagnóstico de hernia inguinal tratados por los autores en los últimos 8 años. Se incluyeron para el análisis los casos con abordaje laparoscópico, recolectándose sexo, edad, diagnóstico pre e intraoperatorio, procedimientos adicionales, tiempo quirúrgico, complicaciones perioperatorias, tiempo de hospitalización, y morbilidad. Resultados: Se recolectaron 158 intervenciones de hernias inguinales en 102 pacientes, 89 hombres y 13 mujeres, de las cuales 135 (85,4%) fueron por abordaje laparoscópico tipo TAPP. Mediante la laparoscopia se modificó el diagnóstico preoperatorio en 17 pacientes (16,6%). El tiempo quirúrgico promedio fue de 50,5±11,6 minutos, y se presentaron 3 complicaciones perioperatorias y 4 tardías, para una morbilidad total de 5,1%. La estancia hospitalaria fue de 1±0,08 días y el tiempo de seguimiento promedio fue de 7,5±15,4 meses, detectándose 3 recidivas (2,2%) en ese período. Cinco pacientes presentaron dolor crónico posoperatorio, ninguno debilitante, que cedió gradualmente en todos los casos utilizando analgésicos comunes. Conclusiones: La técnica TAPP es una alternativa válida en el tratamiento de la hernia inguinal. Sus principales ventajas son las de optimizar el diagnóstico, permitiendo la reparación en un solo tiempo de hernias no diagnosticadas clínicamente, y su baja incidencia de dolor posoperatorio crónico.

Perioperative Use of Gabapentinoids for the Management of Postoperative Acute Pain

Widely used for acute pain management, the clinical benefit from perioperative use of gabapentinoids is uncertain. The aim of this systematic review was to assess the analgesic effect and adverse events with the perioperative use of gabapentinoids in adult patients. Randomized controlled trials studying the use of gabapentinoids in adult patients undergoing surgery were included. The primary outcome was the intensity of postoperative acute pain. Secondary outcomes included the intensity of postoperative subacute pain, incidence of postoperative chronic pain, cumulative opioid use, persistent opioid use, lengths of stay, and adverse events. The clinical significance of the summary estimates was assessed based on established thresholds for minimally important differences. In total, 281 trials (N = 24,682 participants) were included in this meta-analysis. Compared with controls, gabapentinoids were associated with a lower postoperative pain intensity (100-point scale) at 6 h (mean difference, -10; 95% CI, -12 to -9), 12 h (mean difference, -9; 95% CI, -10 to -7), 24 h (mean difference, -7; 95% CI, -8 to -6), and 48 h (mean difference, -3; 95% CI, -5 to -1). This effect was not clinically significant ranging below the minimally important difference (10 points out of 100) for each time point. These results were consistent regardless of the type of drug (gabapentin or pregabalin). No effect was observed on pain intensity at 72 h, subacute and chronic pain. The use of gabapentinoids was associated with a lower risk of postoperative nausea and vomiting but with more dizziness and visual disturbance. No clinically significant analgesic effect for the perioperative use of gabapentinoids was observed. There was also no effect on the prevention of postoperative chronic pain and a greater risk of adverse events. These results do not support the routine use of pregabalin or gabapentin for the management of postoperative pain in adult patients.

Application of double circular suturing technique (DCST) in the repair of large abdominal wall defects after resection of abdominal wall tumor.

BackgroundThe aim of this study was to investigate the clinical effects of repairing large defects using the double circular suturing technique (DCST) after resection of abdominal wall tumor.MethodsThe clinical data of 62 patients (25 men, 37 women; average age 41.7±22.4 years) who underwent DCST between October 2010 and November 2018 for the repair of large abdominal wall defects with anti-adhesion underlay mesh after resection of abdominal wall tumor were retrospectively analyzed. The maximum diameter of abdominal wall defect after resection of abdominal wall tumor was 10.4±5.6 cm. The course of disease was 1–341 months, and the average was 32.4 months. Operative time, postoperative hospitalization time, perioperative complications, tumor recurrence in situ, incidence of postoperative chronic pain, and hernia were recorded.ResultsAll 62 operations were completed successfully. The operative time was 73.2±31.4 minutes, and the mean postoperative hospitalization time was 9.6 days (range, 2–20 days). In total, 54 patients were followed up postoperatively for a median 6.7 years (range, 0.9–9.0 years). Partial splitting of incisions occurred in 2 patients, fat liquefaction of incisions occurred in 3 patients, and chronic pain occurred in 4 patients. No tumor in situ recurrence, hernia, or other complications were found in any cases in the follow-up. Tumor metastasis occurred in 9 patients with 6 of these patients dying of tumour progression.ConclusionsWith simple operations, short procedure time, few complications, low tumor recurrence rate, and low incidence of postoperative chronic pain, application of DCST in the repair of large abdominal wall defects is effective after resection of abdominal wall tumor.

PECS II block is associated with lower incidence of chronic pain after breast surgery.

BackgroundBreast cancer is complicated by a high incidence of chronic postoperative pain (25%–60%). Regional anesthesia might play an important role in lowering the incidence of chronic pain; however it is not known if the pectoral nerve block (PECS block), which is commonly used for breast surgery, is able to prevent this complication. Our main objective was therefore to detect any association between the PECS block and chronic pain at 3, 6, 9, and 12 months in patients undergoing breast surgery.MethodsWe conducted a prospective, monocentric, observational study. We enrolled 140 consecutive patients undergoing breast surgery and divided them in patients receiving a PECS block and general anesthesia (PECS group) and patients receiving only general anesthesia (GA group). Then we considered both intraoperative variables (intravenous opioids administration), postoperative data (pain suffered by the patients during the first 24 postoperative hours and the need for additional analgesic administration) and development and persistence of chronic pain (at 3, 6, 9, and 12 mo).ResultsThe PECS group had a lower incidence of chronic pain at 3 months (14.9% vs. 31.8%, P = 0.039), needed less intraoperative opioids (fentanyl 1.61 μg/kg/hr vs. 3.3 μg/kg/hr, P < 0.001) and had less postoperative pain (3 vs. 4, P = 0.017).ConclusionsThe PECS block might play an important role in lowering incidence of chronic pain, but further studies are needed.

Evaluation of Cyanoacrylate Glue in Mesh Fixation in Non-Incisional Ventral Hernia

AbstractBackground: The occurrence of post-operative chronic pain after mesh hernioplasty in nonincisional ventral hernia is especially disturbing as it is felt by 0-43% of patients, 11% on average. Post-operative pain is the consequence of tissue dissection and post-operative local inflammation. As a result, the surrounding nerves become damaged and painful stimu-lation occurs. The cyanoacrylate glue, the characteristic of histoacryl such as efficacy, excellent local tolerability, and less of adverse effects makes it an optimal choice for the atraumatic mesh fixation. It has been used in a variety of surgical fields for its effectiveness, excellent local tolerability and relative lack of adverse effects and contraindications. However, the hospital costs were increased by the use of cyanoacrylate glue instead of the sutures.Aim of Study: The aim of this study is to evaluate the feasibility, efficacy of cyanoacrylate glue in mesh fixation in non-incisional ventral hernia repair as regard the operative time, the post-operative pain, the occurrence of wound seroma and recurrence rate.Patients and Methods: This prospective study was carried out on 20 patients of different ages in either sex presented with nonincisional ventral hernia who were subjected to mesh hernioplasty with cyanoacrylate glue. They were followed-up for chronic pain, seroma, recurrence.Results: The post-operative pain was evaluated in 1st month and at 6 months by visual analogue score, 8 out of 20 patients (40%) had mild pain and 2 out of 20 patients (10%) had moderate pain. Shrinkage of the mesh reported in 2 out of 20 patients (10%) and 5 out of 20 patients (25%) developed seroma over the mesh that resolved on conservative treatment. No recurrence of the hernia during the follow-up period by clinical examination and by abdominal ultrasound.Conclusion: The mesh fixation with cyanoacrylate glue in nonincisional ventral hernia is more expensive than using sutures in mesh fixation but, it can reduce the need for analgesics and improve life style by decreasing incidence of chronic post-operative pain. We recommend performing further studies with larger population.

ROLE OF ROUTINE ILIOINGUINAL NEURECTOMY IN PREVENTION OF CHRONIC POST OPERATIVE PAIN FOLLOWING LICHTENSTEIN HERNIOPLASTY

BACKGROUND : Lichtenstein hernioplasty is a widely performed surgery for the repair of groin hernia. Postoperative pain is a frequent and disabling complication of this surgery. The ilioinguinal nerve, due to it’s close proximity immediately beneath the divided external oblique fascia, is most frequently involved. Theoretically, ilioinguinal nerve excision looks lucrative in prevention of postoperative neuralgia due to nerve entrapment in sutures, inflammation, fibrosis or neuroma. Methods: 120 patients with confirmed diagnosis of inguinal hernia reporting to surgery OPD and undergoing surgery were randomized in two groups: Group A (60 patients ) in which prophylactic ilioinguinal neurectomy was performed and Group B (60 patients ) in which the ilioinguinal nerve was preserved. Results: At POD 1, 2nd week, one month post operatively, the pain in the neurectomy group was lesser though it was statistically significant only at rest. However, the post operative pain was significantly lesser in neurectomy group at 3 months post operatively (p=0.024 at rest, p=0.049 during coughing, p=0.036 during walking). Numbness at post operative day 1 and until one month after surgery, was significantly higher in the neurectomy group. But the degree of numbness was insignificant in the two groups thereafter. Conclusion: Ilioinguinal neurectomy results in significantly lower incidence of chronic postoperative pain. Even in early postoperative period, the pain severity in neurectomy patients is much less than that in control group. But there is a side effect of increased incidence of numbness in area of sensory innervations of the nerve in patients undergoing elective neurectomy in the initial post operative days. This numbness should not condemn the procedure as this improved with time and the incidence was almost similar in the two groups in the long run.

SURGICAL MINI-FLANK APPROACH TO THE KIDNEY WITH LOCALIZED RENAL CELL CARCINOMA

The aim of the study was an attempt to improve the results of organ-preserving treatment of patients with localized renal cell carcinoma by developing and using abdominal intermuscular mini- flank approach to the kidney.Material and methods. We analyzed the data of 119 patients who underwent partial nephrectomy for renal cell carcinoma at the N.N. Petrov National Medical Research Center of Oncology from 2004 to 2013 years from three types of surgical approach: through an open classical lumbotomy, laparoscopically and through the original abdominal intermuscular mini-flank approach. The following parameters were studied: the duration of the operation, the time of renal artery ischemia, the volume of blood loss, the number of patients requiring hemotransfusion, as well as the oncological and functional results of partial nephrectomy, the cosmetic effect and the frequency of the formation of chronic postoperative pain.Results. It is demonstrated that the proposed original intermuscular mini- flank approach as well as laparoscopic approach provides a good cosmetic effect, preserves the function of the anterior abdominal wall and reliably reduces the incidence of chronic postoperative pain compared to open classical lumbotomy.

Evaluation of pulsed electromagnetic field therapy for the treatment of chronic postoperative pain following lumbar surgery: a pilot, double-blind, randomized, sham-controlled clinical trial.

BackgroundThe incidence of chronic postoperative pain following lumbar spinal surgery has increased with the overall increase in the prevalence of lumbar surgery. This study was conducted to evaluate the analgesic effectiveness of pulsed electromagnetic field (PEMF) therapy in subjects with persistent pain following lumbar surgery.Patients and methodsA randomized, double-blind, sham-controlled, multicenter study in 36 subjects with persistent low-back and/or radiating leg pain after lumbar surgery was conducted. Eligible subjects were randomized (1:1:1) to receive one of two doses of therapy (42-μs or 38-μs pulse width) or treatment with a sham device. Subjects self-treated twice daily for 60 days. The primary end point was change in pain intensity (∆PI) using the Numerical Pain Rating Scale between average baseline (Days −5 to −1) and end of treatment (Days 56–60) for lumbar and radiating leg pain. Secondary outcome measures included the Oswestry Disability Index, Beck Depression Inventory-II, Patient Global Impression of Change, and consumption of analgesics.ResultsLow-back pain scores for the 42-μs group decreased by 40.2% (p = 0.028), compared to 18.6% for the 38-μs pulse width group (p = 0.037) and 25.6% for the sham group (p = 0.013 per protocol population). Average leg pain scores decreased by 45.0% (42 μs, p = 0.009), 17.0% (38 μs, p = 0.293), and 24.5% (sham, p = 0.065). The proportion of subjects responding to therapy, time to 30% reduction in pain scores, and Patient Global Impression of Change were improved with the PEMF 42-μs device over the sham control, although results were associated with p-values >0.05.ConclusionPEMF therapy (42-μs pulse width) was associated with trends for a reduction in pain, compared to sham treatment. Secondary endpoints were consistent with an overall beneficial effect of the PEMF 42-μs pulse width device.

Thoracic paravertebral block for postoperative pain management after renal surgery: A randomised controlled trial.

Thoracic paravertebral block (ThPVB) combined with general anaesthesia is used in thoracic and general surgery. It provides effective analgesia, reduces surgical stress response and the incidence of chronic postoperative pain. To assess the efficacy of ThPVB in reducing opioid requirements and decreasing the intensity of pain after renal surgery. A randomised, open label study. A single university hospital. Study conducted from August 2013 to February 2014. In total, 68 patients scheduled for elective renal surgery (open nephrectomy or open nephron-sparing surgery). Preoperative ThPVB with 0.5% bupivacaine combined with general anaesthesia, followed by postoperative oxycodone combined with nonopioid analgesics as rescue drugs. Follow-up period: 48 h. Total dose of postoperative oxycodone required, pain intensity, occurrence of opioid related adverse events, ThPVB-related adverse events and patient satisfaction. A total of 68 patients were randomised into two groups and, of these, 10 were subsequently excluded from analysis. Patients in group paravertebral block (PVB; n = 27) had general anaesthesia and ThPVB, and those in group general (anaesthesia) (GEN) (n = 31) formed a control group receiving general anaesthesia only. Compared with patients in group GEN, patients who received ThPVB required 39% less i.v. oxycodone over the first 48 h and had less pain at rest (P < 0.01) throughout the first 24 h. Group PVB patients also experienced fewer opioid-related adverse events and were less sedated during the first 12 postoperative hours. Patients in the PVB group had higher satisfaction scores at 48 h compared with the control group. There were no serious adverse events. In our study, preoperative ThPVB was an effective part of a multimodal analgesia regimen for reducing opioid consumption and pain intensity. Methods and drugs used in both groups were well tolerated with no serious adverse events. Compared with the control group, patients in the ThPVB group reported increased satisfaction. Clinical Trials NCT02840526.

Chronic postoperative pain: recent findings in understanding and management.

Chronic postoperative pain is a poorly recognized potential outcome from surgery. It affects millions of patients every year, with pain lasting for months to years, resulting in patient suffering and ensuing economic consequences. The operations with the highest incidence of chronic postoperative pain are amputations, thoracotomies, cardiac surgery, and breast surgery. Other risk factors include preoperative pain, psychological factors, demographics, and the intensity of acute postoperative pain. Attempts to prevent chronic postoperative pain have often led to debatable results. This article presents data from recently published studies examining the incidence, risk factors, mechanisms, treatment options, and preventive strategies for chronic postoperative pain in adults. In summary, many of the previously identified risk factors for chronic postoperative pain have been confirmed and some novel ones discovered, such as the importance of the trajectory of acute pain and the fact that catastrophizing may not always be predictive. The incidence of chronic postoperative pain hasn’t changed over time, and there is limited new information regarding an effective preventive therapy. For example, pregabalin may actually cause more harm in certain surgeries. Further research is needed to demonstrate whether multimodal analgesic techniques have the best chance of significantly reducing the incidence of chronic postoperative pain and to determine which combination of agents is best for given surgical types and different patient populations.

(275) Interaction among keratinocytes, fibroblasts and CD163-overexpressing macrophages for a more efficient wound healing process

Peripheral neuroimmune interactions play an important role in the development of pain and wound healing process after surgery. We hypothesize that the over-expression of the scavenger receptor gene CD163 in human macrophages will promote an M2 cellular phenotype that will promote a more efficient wound healing process. We will test this hypothesis following these aims: 1) Induce CD163 in macrophages using a nanoparticle that target these cells specifically; 2) Promote a more efficient wound healing process with CD163 overexpressing macrophages using an in vitro assay; and 3) Determine that the observed effects are achieved specifically by the overexpression of CD163. For this purpose, we used an in vitro wound healing scratch assay with primary human keratinocytes and fibroblasts co-cultured with macrophages overexpressing CD163 (or control groups) in the presence or absence of antibodies, anti-CD163 antibody [RM3/1] or its isotype control IgG1. Microscopy, imaging analysis, gene transfection using mannosylated nanoparticle (mPEI) for targeting specifically macrophages and RT-qPCR were performed. We have previously shown that the induction of CD163 in macrophages successfully promotes an anti-inflammatory phenotype. We confirmed the over-expression of CD163 in M1 macrophages at 48 and 72 hours after transfection. Using an in vitro scratch assay we also observed that the addition of CD163-blocking antibody, but not isotype control, blocked the efficient and faster wound healing process induced by CD163-overexpressing macrophages. Moreover, the interaction among keratinocytes, fibroblasts and CD163-overexpressing macrophages resulted in an increased CD163 gene expression in these macrophages. CD163 seems to play a critical role in the induction of wound healing by promoting an anti-inflammatory phenotype in macrophages. We further postulate that this approach could promote a more efficient wound healing process following major surgeries, which would reduce the incidence of chronic postoperative pain. Supported by Rita-Allen-Foundation & American-Pain-Society 2011-Pain-grant (EAR-S); National-Institutes-of-Health, NIGMS, R15GM109333 (EAR-S); 2015-PRSI-program (PCSP); Presbyterian-College-School-of-Pharmacy (DF,AA) and CAPES-Foundation: Ministry-of-Education-of-Brazil (PDSE:BEX10794/14-0).

Evaluation of the knowledge of postoperative pain among participants of a virtual scientific journey in Anesthesiology

BACKGROUND AND OBJECTIVES: Postoperative pain still undertreated, which is associated to increased morbidity and mortality. This study aimed at evaluating the knowledge of physicians participating in a virtual journey in Anesthesiology. Anesthesiologists are professionals often involved with postoperative pain management. METHODS: Five hundred participants of a virtual journey in Anesthesiology were invited to answer a questionnaire available in SurveyMonkey website on specific knowledge of postoperative pain and its management. RESULTS: The questionnaire was answered by 136 individuals and, according to 94.86% of them, postoperative pain management may decrease the incidence of chronic postoperative pain. For 72 (52.95%) participants, postoperative pain is adequately managed in their workplaces. For 71 participants, more than 50% of patients refer postoperative pain. Excluding fear of anesthesia, major concerns of patients, according to 49.26 and 37.5% of respondents, is fear of feeling pain during surgery and after surgery, respectively. For 74 (75%) participants, analgesic prescription as needed should be avoided for postoperative pain. CONCLUSION: In general, participants of the virtual journey are not familiar with the problems of postoperative pain, probably due to their limited contact with hospitalized patients. These deficiencies may be solved with ongoing education and and improvements in the medical school curricula and residency programs.

Staple Fixation Against Adhesive Fixation in Laparoscopic Inguinal Hernia Repair: A Meta-Analysis of Randomized Controlled Trials.

The aim of this article was to compare the outcomes of tissue adhesive fixation and the staple fixation of meshes in laparoscopic inguinal hernia repair. A systematic literature review was undertaken to identify studies that compare adhesive fixation and staple fixation of meshes in laparoscopic inguinal hernia repair. The present meta-analysis pooled the effects of outcomes of a total of 1228 patients enrolled into 8 randomized controlled trials. Tissue adhesive fixation of the mesh was associated with less chronic postoperative pain after laparoscopic inguinal hernia repair compared with staple fixation (risk difference=-0.06; 95% confidence interval, -0.08, -0.04). However, statistically, there was no significant difference in the incidence of acute postoperative pain, recurrence, hematoma/seroma, and wound infection. The use of the tissue adhesive fixation method reduces the incidence of chronic postoperative pain after laparoscopic inguinal hernia repair, and without any changes in the other outcomes.