Postoperative analgesia with continuous wound infusion of local anaesthesia vs saline: a double-blind randomized, controlled trial in colorectal surgery

Perioperative pain management with regional analgesia techniques for visceral cancer surgery: A systematic review and meta-analysis

STUDY OBJECTIVE

Regional analgesia following visceral cancer surgery might provide an advantage but evidence for best treatment options related to risk-benefit is unclear.

DESIGN

Systematic review of randomized controlled trials (RCT) with meta-analysis and GRADE assessment.

SETTING

Postoperative pain treatment.

PATIENTS

Adult patients undergoing visceral cancer surgery.

INTERVENTIONS

Any kind of peripheral (PRA) or epidural analgesia (EA) with/without systemic analgesia (SA) was compared to SA with or without placebo treatment or any other regional anaesthetic techniques.

MEASUREMENTS

Primary outcome measures were postoperative acute pain intensity at rest and during activity 24 h after surgery, the number of patients with block-related adverse events and postoperative paralytic ileus.

MAIN RESULTS

59 RCTs (4345 participants) were included. EA may reduce pain intensity at rest (mean difference (MD) -1.05; 95% confidence interval (CI): -1.35 to -0.75, low certainty evidence) and during activity 24 h after surgery (MD -1.83; 95% CI: -2.34 to -1.33, very low certainty evidence). PRA likely results in little difference in pain intensity at rest (MD -0.75; 95% CI: -1.20 to -0.31, moderate certainty evidence) and pain during activity (MD -0.93; 95% CI: -1.34 to -0.53, moderate certainty evidence) 24 h after surgery compared to SA. There may be no difference in block-related adverse events (very low certainty evidence) and development of paralytic ileus (very low certainty of evidence) between EA, respectively PRA and SA.

CONCLUSIONS

Following visceral cancer surgery EA may reduce pain intensity. In contrast, PRA had only limited effects on pain intensity at rest and during activity. However, we are uncertain regarding the effect of both techniques on block-related adverse events and paralytic ileus. Further research is required focusing on regional analgesia techniques especially following laparoscopic visceral cancer surgery.

The Influence of Analgesic Wound Infiltration on Postoperative Pain and Inflammatory Cytokines in Open Colorectal Surgery: A Randomized Comparative Pilot Study

Background and Objectives: Surgical wound analgesia has been analyzed in many studies, but few have focused on its relationship with inflammatory markers. As such, we aimed to determine the influence of analgesic surgical wound infiltration in open colorectal surgery on the seric levels of pro- and anti-inflammatory markers and the associated efficacy in postoperative pain control. Materials and Methods: Forty patients who underwent open colorectal surgery were prospectively randomized: group 0, epidural analgesia; group 1, intravenous analgesia (control), group 2, preincision and prelaparoraphy infiltration; and, group 3, prelaparoraphy infiltration. Wound infiltration was performed with ropivacaine. We analyzed the levels of IL-6 and IL-10 cytokines before and 6 h after surgery and their correlation with pain scores. Results: The postoperative Il-6 levels were significantly lower in group 0 than in the control (p = 0.041). The postoperative Il-10 levels were significantly higher in group 3 (p = 0.029) than in the control. Six hours after the operation, the pain scores were significantly lower in all groups than in the control (p = 0.005, p = 0.022, and p = 0.017 for groups 0, 2, and 3, respectively). Pain scores were significantly correlated with Il-10 levels in group 2 (p = 0.047); in group 3, IL-10 levels directly correlated with those of Il-6 (p = 0.026). Conclusions: The analgetic effect of preincisional and prelaparoraphy analgetic infiltration was efficient. The analgetic infiltration of the surgical wound prior to closure stimulates both the inflammatory activator and regulator interleukins.

PROcedure-SPECific postoperative pain management guideline for laparoscopic colorectal surgery: A systematic review with recommendations for postoperative pain management

Colorectal cancer is the second most common cancer diagnosed in women and third most common in men. Laparoscopic resection has become the standard surgical technique worldwide given its notable benefits, mainly the shorter length of stay and less postoperative pain. The aim of this systematic review was to evaluate the current literature on postoperative pain management following laparoscopic colorectal surgery and update previous procedure-specific pain management recommendations. The primary outcomes were postoperative pain scores and opioid requirements. We also considered study quality, clinical relevance of trial design, and a comprehensive risk-benefit assessment of the analgesic intervention. We performed a literature search to identify randomised controlled studies (RCTs) published before January 2022. Seventy-two studies were included in the present analysis. Through the established PROSPECT process, we recommend basic analgesia (paracetamol for rectal surgery, and paracetamol with either a nonsteroidal anti-inflammatory drug or cyclo-oxygenase-2-specific inhibitor for colonic surgery) and wound infiltration as first-line interventions. No consensus could be achieved either for the use of intrathecal morphine or intravenous lidocaine; no recommendation can be made for these interventions. However, intravenous lidocaine may be considered when basic analgesia cannot be provided.

A prospective cohort study to evaluate continuous wound infusion with local analgesics within an enhanced recovery protocol after colorectal cancer surgery

AIM

To reduce detrimental opioid-related side effects, minimising the postoperative opioid consumption is needed, especially in older patients. Continuous wound infusion (CWI) with local analgesics appears to be an effective opioid-sparing alternative. However, the added value of CWI to an enhanced recovery protocol after colorectal cancer (CRC) surgery is unclear. The aim of this study was to evaluate the outcomes of CWI after CRC surgery within a strictly adhered to enhanced recovery protocol.

METHODS

In this multicentre prospective observational cohort study, patients who underwent CRC surgery between May 2019 and January 2021 were included. Patients were treated with CWI as adjunct to multimodal pain management within an enhanced recovery protocol. Postoperative opioid consumption, pain scores and outcomes regarding functional recovery were evaluated.

RESULTS

A cohort of 130 consecutive patients were included, of whom 36.2% were ≥75 years. Postoperative opioids were consumed by 80 (61.5%) patients on postoperative day 0, and by 28 (21.5%), 27 (20.8%), and 18 (13.8%) patients on postoperative days 1, 2, and 3, respectively. Median pain scores were <4 on all days. The median time until first passage of stool was 1.0 (IQR: 1.0-2.0) day. Postoperative delirium occurred in 0.8%. Median length of hospital stay was 3.0 days (IQR: 2.0-5.0).

CONCLUSION

In patients treated with CWI, low amounts of postoperative opioid consumption, adequate postoperative pain control, and enhanced recovery were observed. CWI seems a beneficial opioid-sparing alternative and may further improve the outcomes of an enhanced recovery protocol after CRC surgery, which seems especially valuable for older patients.

Preperitoneal ropivacaine infusion versus epidural ropivacaine-morphine for postoperative analgesia in dogs undergoing ovariohysterectomy: a randomized clinical trial

OBJECTIVE

To assess the effect of continuous wound infusion (CWI) with preperitoneal ropivacaine on postoperative analgesia and compare it with the epidural administration of ropivacaine and morphine in bitches undergoing ovariohysterectomy.

STUDY DESIGN

A parallel, randomized, clinical, prospective and nonblinded study.

ANIMALS

A group of 38 Greyhound bitches.

METHODS

In the catheter group (CathG), CWI with ropivacaine 1% (1 mg kg^-1 + 0.8 mg kg^-1 hour^-1) was applied to the preperitoneal space over the surgical incision. In the epidural group (EpiG), ropivacaine 0.5% (1.3 mg kg^-1) and morphine (0.1 mg kg^-1) were epidurally administered. Occipital-coccygeal length was used to calculate the volume for the epidural. Pain was scored using a dynamic interactive visual analogue scale (DIVAS) and Glasgow composite measure pain scale-short form (CMPS-SF) before anaesthesia and at 2, 4, 6, 18, 21 and 24 hours after extubation. Incisional sensitivity using a dynamometer (MWTs-incision) was evaluated simultaneously. Plasma ropivacaine and cortisol concentrations, degree of sedation, motor blockade and response to interdigital clamping were measured or assessed. A two-way mixed analysis of variance and a Mann-Whitney U test were used to analyse data; p < 0.05.

RESULTS

No differences were detected in the DIVAS (p = 0.301), CMPS-SF (p = 0.600) scores, MWTs-incision measurements (p = 0.257) and cortisol values (p = 0.878) between the groups. Rescue analgesia was required in two dogs, one in each group, at 2 hours. Sedation, motor blockade and negative response to interdigital clamping were detected in EpiG at 2, 4 and 6 hours. Mean plasma ropivacaine values were higher in CathG (0.475 ± 0.164 ng mL^-1) than in EpiG (0.184 ± 0.213 ng mL^-1; p = 0.001).

CONCLUSION AND CLINICAL RELEVANCE

Compared with epidural ropivacaine and morphine, CWI with preperitoneal ropivacaine is an effective analgesic technique for postoperative pain management in bitches undergoing ovariohysterectomy without motor blockade.

Effectiveness of Pain Control of Local Anaesthetic Wound Infusion Following Elective Midline Laparotomy: A Randomized Trial

BACKGROUND

Post-operative pain control is an important pillar in enhanced recovery after surgery. There is a paucity of data that compares efficacy of pain control between continuous local anaesthetic wound infusion and thoracic epidural analgesia in elective midline laparotomy patients OBJECTIVE: To evaluate pain control between continuous local anaesthetic wound infusion and thoracic epidural analgesia in elective laparotomy patients.

DESIGN

A randomized, single-blind, controlled clinical trial.

SETTING

Aga Khan University Hospital, Nairobi, Kenya.

POPULATION

Patients underwent elective laparotomy.

METHODS

Thirty-eight patients scheduled for elective laparotomy were randomized into two equal groups to receive either continuous local anaesthetic wound infusion or thoracic epidural analgesia. Data on the baseline patient characteristics, total morphine consumption at 72 h, visual analogue scores and rates of adverse effects were collected.

RESULTS

Baseline characteristics of the participants were similar. Continuous local anaesthetic wound infusion was equivalent to thoracic epidural analgesia in terms of pain scores and total morphine consumption at 72 h. Duration of hospital stay was shorter in the intervention arm. There were more surgical site infections in the intervention arm, while catheter dislodgement rate was higher in the thoracic epidural arm.

CONCLUSION

Continuous local anaesthetic wound infusion is equivalent to thoracic epidural analgesia in management of post-operative pain following elective midline laparotomy.

CLINICAL TRIAL REGISTRATION

Pan African Clinical Trial registry, number PACTR201808607220790.

Continuous wound infusion with ropivacaine alone provides adequate analgesia following laparotomy

BACKGROUND

Although continuous wound infusion (CWI) with local anaesthetic has been used as an adjunct for pain relief following laparotomy, its use as the main modality has not been studied. This approach negates side effects related to intravenous opioid administration, therefore promoting enhanced recovery from surgery. We conducted this study to investigate the feasibility and efficacy of CWI following laparotomy.

METHODS

Consecutive patients who underwent laparotomy from June 2016 to December 2019 were analysed. All patients were given CWI with only oral supplementation. Pain was assessed based on the numeric rating scale (NRS).

RESULTS

One hundred and three patients were analysed. Mean age was 61.1 (standard deviation 16.7). 47.6% of patients were operated for intestinal obstruction. Large bowel resection was the most common operation performed (49.5%). 69.9% of patients underwent emergency surgery, whilst 51.5% of patients had surgery for cancer. On postoperative day 0, NRS was 3.2 (standard deviation (sd) 2.6) which decreased to 1.5 (sd 1.9) on day 3, and 1.1 (sd 1.8) on day 5. Mean time to flatus was 2.3 (sd 1.4) days, whilst mean time to first bowel movement was 3.1 (sd 1.7) days. Patients were able to commence ambulation by 2.5 (sd 1.8) days. Patients could tolerate a normal diet on day 3.9 (sd 3.3), and IV drip was removed on day 3.5 (sd 3.0). Mean length of stay was 9.1 (sd 6.9) days. Only two patients suffered from respiratory depression (1.9%) whilst five patients suffered from hypotension (4.9%). No patients had pruritus. 23.3% of patients had nausea or vomiting. Only one patient had a catheter-related complication which was easily addressed.

CONCLUSION

CWI provides adequate pain relief as the principle modality of analgesia after surgery, without opioid side effects.

Opioid-Sparing Effect of Liposomal Bupivacaine and Intravenous Acetaminophen in Colorectal Surgery

BACKGROUND

This study evaluated the opioid-sparing effect of liposomal bupivacaine and intravenous acetaminophen in colorectal surgery.

MATERIALS AND METHODS

This study was a retrospective, 2 × 2 factorial cohort conducted at an academic medical center from May 2016 to February 2018. Patients undergoing open or minimally invasive colorectal resection were included. Exclusion criteria were age <18 y, surgery after second hospital day, ostomy, and allergy to acetaminophen, opioids, or bupivacaine. Intraoperative liposomal bupivacaine and intravenous acetaminophen administration within 18 h after surgery were evaluated. The primary outcome was intravenous morphine milligram equivalents administered within 24 h after surgery. A linear regression model adjusted for American Society of Anesthesiologists score, enhanced recovery after surgery management, open surgery, opioid use before surgery, and height was used for the primary analysis.

RESULTS

Among 486 included patients, 193 received both liposomal bupivacaine and intravenous acetaminophen, 93 received liposomal bupivacaine only, 104 received intravenous acetaminophen only, and 96 did not receive either. On average, patients received 21 (SD = 31) morphine equivalents over 24 h. Intraoperative liposomal bupivacaine was associated with a reduction of morphine equivalents (adjusted change -11, 95% CI -17 to -6), but intravenous acetaminophen was not (2, 95% CI -3 to 7). Intraoperative liposomal bupivacaine was associated with a reduction of length of stay (adjusted change = -1.2 d, 95% CI -2.1 to -0.3), but intravenous acetaminophen was not (adjusted change = 1.5 d, 95% CI 0.7 to 2.2).

CONCLUSIONS

Liposomal bupivacaine was associated with a significant reduction of opioid use within 24 h after colorectal surgery, but intravenous acetaminophen was not.

Surgeon-Placed Continuous Wound Infusion Pain Catheters Markedly Decrease Narcotic Use and Improve Outcomes After Pancreatic Tumor Resection

BACKGROUND

Pancreatectomy results in significant postoperative pain and typically requires opioid analgesia for adequate pain control. Local anesthetics may decrease postoperative pain and opioid requirements but can be limited by onset of action, duration of effect, and inability to titrate dosing after administration. This can be overcome by surgeon placement of tunneled peri-incisional catheters with continuous wound infusion (CWI).

METHODS

This retrospective cohort study analyzed patients undergoing open pancreatic tumor resection. All the patients received patient-controlled analgesia (PCA), enabling an objective comparison of opioid requirements, and underwent the same recovery pathway. The patients received CWI (n = 45), PCA alone (n = 11), or epidural analgesia (EA) (n = 9). The primary outcome was total opioid use in terms of intravenous morphine milligram equivalents (MMEs) and patient-reported pain scores on a numeric rating scale (NRS) of 0 to 10.

RESULTS

No differences in baseline patient or tumor characteristics were observed. In both the uni- and multivariate analyses, CWI was associated with lower opioid use than PCA (MME, 83 vs 207 mg; p = 0.004) or EA (MME, 83 vs 156 mg; p < 0.001) without having a negative impact on pain scores. Furthermore, CWI was associated with a greater percentage of time that patients experienced optimal pain control (NRS, ≤ 4: 63% vs 50%; p = 0.033) and a shorter time to PCA independence (4.0 vs 4.9 days; p = 0.004) than PCA alone. In addition, CWI was associated with earlier ambulation [EA vs CWI: odds ratio (OR), 0.05; p = 0.021], improved spirometry performance (CWI vs PCA: regression coefficient (coef), 267; p = 0.013), and earlier urinary catheter removal (EA vs CWI: coef, 1.30; p = 0.013). The findings showed no differences in time to return of bowel function, antiemetic use, or hospital length of stay.

CONCLUSIONS

After open pancreatic tumor resection, CWI is safe and associated with decreased opioid requirements and improved functional outcomes without a negative impact on pain scores, supporting its potential for preferred use over PCA or EA alone.

Postoperative analgesic efficacy of modified continuous transversus abdominis plane block in laparoscopic colorectal surgery: a triple-blind randomized controlled trial

BACKGROUND

The optimal opioid-sparing analgesic regimen following laparoscopic colorectal surgery (LCS) remains uncertain. We sought to determine the efficacy of low-dose bupivacaine infusion via surgeon-inserted modified continuous transversus abdominis plane (mcTAP) catheters after LCS.

METHODS

A parallel-group, placebo-controlled, randomized single-centre trial was conducted between April 2017 and February 2018. Block-of-four randomization and allocation concealment by sequentially-numbered, opaque sealed envelopes were used. Patients, surgeons and assessors were blinded. Fifty-two patients were randomized to receive either 0.2% bupivacaine or saline through mcTAP catheters. A 5 ml bolus followed by a 72 h infusion at 2 ml/h was started, with patient-controlled fentanyl analgesia and oral paracetamol given on demand. Primary outcomes were fentanyl consumptions in the first 24 h, second 24 h, and third 24 h following surgery. Secondary outcomes were pain numeric rating scores, recovery outcomes and complications.

RESULTS

Twenty-five patients in the bupivacaine group and 26 in the control group were analysed. Patients in the bupivacaine group required significantly less fentanyl overall (106.1 vs 484.5 mcg, p < 0.001) and at all time points (first 24 h: 61.0 vs 324.3 mcg, p < 0.001; second 24 h: 36.3 vs 119.0 mcg, p = 0.033; third 24 h: 8.8 vs 41.2, p = 0.030) when compared to placebo. Significantly lower pain scores at rest at 6 h (2.32 vs 4.0, p = 0.002), and 12 h (1.80 vs 3.08, p = 0.011) and on coughing at 6 h (4.56 vs 5.84, p = 0.019), 12 h (3.76 vs 4.96, p = 0.009), and 24 h (3.44 vs 4.24, p = 0.049) as well as significantly lower opioid-related complications such as nausea or vomiting (9 (36%) vs 1 (4%), p = 0.005) were observed in the bupivacaine group. There were no major block-related complications, and recovery outcomes were similar in both groups.

CONCLUSIONS

McTAP block reduces postoperative fentanyl consumption and pain scores after LCS, highlighting its role as a safe and useful opioid-sparing analgesia.

REGISTRATION NUMBER

TCTR20150831001 (Thai Clinical Trials Registry). Full trial protocol can be assessed at https://www.clinicaltrials.in.th/ .

Continuous Wound Infiltration of Local Anesthetics in Postoperative Pain Management: Safety, Efficacy and Current Perspectives

Local infiltration and continuous infusion of surgical wound with anesthetics are parts of multimodal analgesia for postoperative pain control. The techniques, given the simplicity of execution that does not increase the timing of the intervention and does not require additional technical skills, are applied in several kinds of surgeries. The continuous wound infiltration can be used for days and a variety of continuous delivery methods can be chosen, including patient-controlled analgesia, continuous infusion or intermittent bolus. The purpose of this narrative review is to analyze the literature, in particular by researching the safety, efficacy and current perspectives of continuous wound infiltration for postoperative pain management in different surgical settings. We have identified 203 articles and 95 of these have been taken into consideration: 17 for the lower limb surgery; 7 for the upper limb surgery, 51 for the laparotomy/laparoscopic surgery of the abdominopelvic area, 13 studies regarding breast surgery and 7 for cardiothoracic surgery. The analysis of these studies reveals that the technique has a variable effectiveness based on the type of structure involved: it is better in structures rich in subcutaneous and connective tissue, while the effectiveness is limited in anatomic districts with a greater variability of innervation. However, regardless the heterogeneity of results, a general reduction in pain intensity and in opioid consumption has been observed with continuous wound infiltration: it is an excellent analgesic technique that can be included in the multimodal treatment of postoperative pain or represents a valid alternative when other options are contraindicated.

Continuous local anaesthetic wound infusion for postoperative pain after midline laparotomy for colorectal resection in adults

BACKGROUND

Colorectal resection through a midline laparotomy is a commonly performed surgical procedure to treat various bowel conditions. The typical postoperative hospital stay after this operation is 6 to 10 days. The main factors hindering early recovery and discharge are thought to include postoperative pain and delayed return of bowel function.Continuous infusion of a local anaesthetic into tissues surrounding the surgical incision via a multi-lumen indwelling wound catheter placed by the surgeon prior to wound closure may reduce postoperative pain, opioid consumption, the time to return of bowel function, and the length of hospital stay.

OBJECTIVES

To evaluate the efficacy and adverse events of continuous local anaesthetic wound infusion for postoperative pain after midline laparotomy for colorectal resection in adults.

SEARCH METHODS

We searched the CENTRAL, MEDLINE and Embase databases to January 2019 to identify trials relevant to this review. We also searched reference lists of relevant trials and reviews for eligible trials. Additionally, we searched two clinical trials registers for ongoing trials.

SELECTION CRITERIA

We considered randomised controlled trials (including non-standard designs) or quasi-randomised controlled trials comparing continuous wound infusion of a local anaesthetic versus a placebo or a sham after midline laparotomy for colorectal resection in adults. We did not compare continuous local anaesthetic wound infusion to other techniques, such as transverse abdominis plane block or thoracic epidural analgesia. We allowed non-randomised analgesic co-interventions carried out equally in the intervention and control groups.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials for inclusion and assessed their quality using the Cochrane 'Risk of bias' tool. We extracted data using standardised forms, including pain at rest and on movement (10-point scale), opioid consumption via a patient-controlled analgesia (PCA) system (mg morphine equivalent), postoperative opioid-related adverse events, the time to rescue analgesia, the time to first flatus and to first bowel movement, the time to ambulation, the length of hospital stay, serious postoperative adverse events, and patient satisfaction. We quantitatively synthesised the data by meta-analysis. We summarised and graded the certainty of the evidence for critical outcomes using the GRADEpro tool and created a 'Summary of findings' table.

MAIN RESULTS

This review included six randomised controlled trials that enrolled a total of 564 adults undergoing elective midline laparotomy for colorectal resection comparing continuous wound infusion of a local anaesthetic to a normal saline placebo. Due to 23 post-randomisation exclusions, a total of 541 participants contributed data to the analysis of at least one outcome (local anaesthetic 268; control 273). Most participants were aged 55 to 65 years, with normal body mass index and low to moderate anaesthetic risk (American Society of Anesthesiologists class I-III). Random sequence generation, allocation concealment, and blinding were appropriately carried out in most trials. However, we had to downgrade the certainty of the evidence for most outcomes due to serious study limitations (risk of bias), inconsistency, indirectness, imprecision and reporting bias.Primary outcomesOn postoperative day 1, pain at rest (mean difference (MD) -0.59 (from 3.1), 95% confidence interval (CI) -1.12 to -0.07; 5 studies, 511 participants; high-certainty evidence), pain on movement (MD -1.1 (from 6.1), 95% CI -2.3 to -0.01; 3 studies, 407 participants; low-certainty evidence) and opioid consumption via PCA (MD -12 mg (from 41 mg), 95% CI -20 to -4; 6 studies, 528 participants; moderate-certainty evidence) were reduced in the local anaesthetic group compared to the control group.Secondary outcomesThere was a reduction in the time to first bowel movement (MD -0.67 from 4.4 days, 95% CI -1.17 to -0.17; 4 studies, 197 participants; moderate-certainty evidence) and the length of hospital stay (MD -1.2 from 7.4 days, 95% CI -2.0 to -0.3; 4 studies, 456 participants; high-certainty evidence) in the local anaesthetic group compared to the control group.There was no evidence of a difference in any serious postoperative adverse events until hospital discharge (RR 1.04, 95% CI 0.68 to 1.58; 6 studies, 541 participants; low-certainty evidence) between the two study groups.

AUTHORS' CONCLUSIONS

After elective midline laparotomy for colorectal resection, continuous wound infusion of a local anaesthetic compared to a normal saline placebo reduces postoperative pain at rest and the length of hospital stay, on the basis of high-certainty evidence. This means we are very confident that the effect estimates for these outcomes lie close to the true effects. There is moderate-certainty evidence to indicate that the intervention probably reduces opioid consumption via PCA and the time to first bowel movement. This means we are moderately confident that effect estimates for these outcomes are likely to be close to the true effects, but there is a possibility that they are substantially different. The intervention may reduce postoperative pain on movement, however, this conclusion is based on low-certainty evidence. This means our confidence in the effect estimate is limited. The true effect may be substantially different from the estimate of the effect. There is low-certainty evidence to indicate that the intervention may have little or no effect on the rates of any serious postoperative adverse events until hospital discharge. High-quality randomised controlled trials to evaluate the intervention with a focus on important clinical and patient-centred outcomes are needed.

Comparison of ultrasound-guided transmuscular quadratus lumborum block catheter technique with surgical pre-peritoneal catheter for postoperative analgesia in abdominal surgery: a randomised controlled trial

Following abdominal surgery, the provision of postoperative analgesia with local anaesthetic infusion through both transmuscular quadratus lumborum block and pre-peritoneal catheter have been described. This study compared these two methods of postoperative analgesia following laparotomy. Eighty-two patients 18-85 years of age scheduled to undergo elective surgery were randomly allocated to receive either transmuscular quadratus lumborum block or pre-peritoneal catheter block. In the transmuscular quadratus lumborum group, an 18-gauge Tuohy needle was passed through the quadratus lumborum muscle under ultrasound guidance to reach its anterior aspect. A 20-ml bolus of ropivacaine 0.375% was administered and catheters placed bilaterally. In the pre-peritoneal catheter group, 20 ml of ropivacaine 0.375% was infiltrated at each of three subcutaneous sub-fascial levels, and pre-peritoneal plane catheters were placed bilaterally. Both groups received an infusion of ropivacaine 0.2% at 5 ml.h^-1 , continued up to 48 h along with a multimodal analgesic regime that included regular paracetamol and patient-controlled analgesia with fentanyl. The primary end-point was postoperative pain score on coughing, assessed using a numerical rating score (0-10). Secondary outcomes were pain score at rest, fentanyl usage until 48 h post-operation, satisfaction scores and costs. There was no treatment difference between the two groups for pain score on coughing (p = 0.24). In the transmuscular quadratus lumborum group, there was a reduction in numerical rating score at rest (p = 0.036) and satisfaction scores on days 1 and 30 (p = 0.004, p = 0.006, respectively), but fentanyl usage was similar. In the transmuscular quadratus lumborum group, the highest and lowest blocks observed in the recovery area were T4 and L1, respectively. The transmuscular quadratus lumborum technique cost 574.64 Australian dollars more per patient than the pre-peritoneal catheter technique.

Guidelines for Perioperative Care in Elective Colorectal Surgery: Enhanced Recovery After Surgery (ERAS®) Society Recommendations: 2018

BACKGROUND

This is the fourth updated Enhanced Recovery After Surgery (ERAS®) Society guideline presenting a consensus for optimal perioperative care in colorectal surgery and providing graded recommendations for each ERAS item within the ERAS® protocol.

METHODS

A wide database search on English literature publications was performed. Studies on each item within the protocol were selected with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohorts and examined, reviewed and graded according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system.

RESULTS

All recommendations on ERAS® protocol items are based on best available evidence; good-quality trials; meta-analyses of good-quality trials; or large cohort studies. The level of evidence for the use of each item is presented accordingly.

CONCLUSIONS

The evidence base and recommendation for items within the multimodal perioperative care pathway are presented by the ERAS® Society in this comprehensive consensus review.

Ropivacaine preperitoneal wound infusion for pain relief and prevention of incisional hyperalgesia after laparoscopic colorectal surgery: a randomized, triple-arm, double-blind controlled evaluation vs intravenous lidocaine infusion, the CATCH study

AIM

The abdominal incision for specimen extraction could trigger postoperative pain after laparoscopic colorectal resections (LCRs). Continuous wound infusion (CWI) of ropivacaine may be a valuable option for postoperative analgesia. This study was undertaken to evaluate the potential benefits of ropivacaine CWI on pain relief, metabolic stress reaction, prevention of wound hyperalgesia and residual incisional pain after LCR. A subgroup with intravenous lidocaine infusion (IVL) was added to discriminate between the peripheral and systemic effects of local anaesthetic infusions.

METHOD

Patients were randomly allocated to three subgroups: CWI (0.2% ropivacaine 10 ml/h for 48 h); IVL (lidocaine 1.5% at 4 ml/h for 48 h); control group.

RESULTS

In all, 95 patients were randomized (86 patients analysed). Postoperative pain intensity did not differ significantly between groups. Within the first 24 h after surgery, morphine requirement was significantly lower in the CWI group compared with the IVL group, but there was no significant difference compared with the control group (P = 0.02 and P = 0.15, respectively). The area of hyperalgesia did not differ significantly between subgroups, nor did the hyperalgesia ratio which was 1.2 cm (0.0-6.7) vs 1.9 cm (0.4-4.0) vs 2.0 cm (0.5-7.0) in the CWI, IVL and control groups respectively (P = 0.35). The number of patients reporting residual incisional pain after 3 months (3/26 vs 4/23 vs 4/23 in the CWI, IVL and control groups respectively) did not differ significantly between the groups, nor did their metabolic stress reactions.

CONCLUSION

Ropivacaine CWI at the site of the abdominal incision did not provide any significant benefit either on analgesia or on the prevention of wound hyperalgesia after LCR.

Endogenous Opiates and Behavior: 2016

This paper is the thirty-ninth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2016 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.

Continuous Wound Infiltration After Hallux Valgus Surgery

BACKGROUND

Hallux valgus surgery is associated with significant early postoperative pain. The aim of this study was to investigate the use of continuous wound infiltration (CWI) with ropivacaine for pain management after hallux valgus surgery.

METHODS

In this prospective, randomized, double-blind, and placebo-controlled single-center trial, 50 patients undergoing distal metatarsal osteotomy for idiopathic hallux valgus were allocated to CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h or placebo for 24 hours postoperatively. Average and peak pain levels on the verbal numeric rating scale (NRS; 1-10) during the first 48 hours after surgery were recorded as primary outcome parameters. Secondary outcome parameters included consumption of narcotics, clinical outcome, incidence of postoperative complications, and patient satisfaction.

RESULTS

No significant difference in mean ( P = .596) and peak ( P = .353) postoperative pain level was found for CWI with either ropivacaine (mean NRS 1.9 ± 0.8; peak NRS 3.5 ± 2.0) or placebo (mean NRS 2.0 ± 0.7; peak NRS 3.9 ± 1.7) during the early postoperative course. Furthermore, no significant difference between both groups was detected regarding narcotic consumption ( P = .354) and all other secondary outcome parameters. Two severe complications (local dysesthesia with CWI, catheter accidentally fixed by a suture) and 5 catheter dislocations were observed.

CONCLUSION

CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h for 24 hours after hallux valgus surgery did not reduce postoperative pain level in an inpatient setting.

LEVEL OF EVIDENCE

Level I, prospective randomized trial.

Analgesia with continuous wound infusion of local anesthetic versus saline: Double-blind randomized, controlled trial in hepatectomy

BACKGROUND

Surgical wound is source of pain in hepatectomy with laparotomy. Continuous wound infusion of ropivacaine may provide effective analgesia.

METHODS

This prospective, randomized trial, patients scheduled for hepatectomy received a 48-h preperitoneal continuous wound infusion of either 0.23% ropivacaine or 0.9% saline at 5 ml/h. Primary endpoint was 48 h morphine consumption.

RESULTS

53 patients included in the ropivacaine group and 46 in the saline group. Morphine consumption was 24.63 mg in the ropivacaine group, and 26.78 mg (p = 0.669) in the saline group. Pain was comparable between groups and there were no differences in solid food intake, ambulation, or length of hospital stay. No local or systemic complications were recorded.

CONCLUSIONS

Continuous wound infusion with ropivacaine is safe, but it neither reduced morphine consumption nor enhanced recovery in patients undergoing hepatectomy. Success of enhanced recovery in hepatectomy is not influenced by the analgesic regimen if pain is well controlled.

The effect of local/topical analgesics on incisional pain in a pig model

Interest in the development of new topical/local drug administration for blocking pain at peripheral sites, with maximum drug activity and minimal systemic effects, is on the rise. In the review article by Kopsky and Stahl, four critical barriers in the process of research and development of topical analgesics were indicated. The active pharmaceutical ingredient (API) and the formulation are among the major challenges. The road to the development of such drugs passes through preclinical studies. These studies, if planned correctly, should serve as guidance for choosing the right API and formulation. Although rodent models for pain continue to provide valuable data on the mechanisms driving pain, their use in developing topical and localized treatment approaches is limited for technical (intraplate injection area is small) as well as mechanical reasons (non-similarity to human skin and innervation). It has been previously shown that pigs are comparable to humans in ways that make them a better choice for evaluating topical and local analgesics. The aim of this study was to summarize several experiments that used pigs for testing postoperative pain in an incisional pain model (skin incision [SI] and skin and muscle incision [SMI]). At the end of the surgery, the animals were treated with different doses of bupivacaine solution (Marcaine^®), bupivacaine liposomal formulation (Exparel^®) or ropivacaine solution (Naropin). Von Frey testing demonstrated a decrease in the animals’ sensitivity to mechanical stimulation expressed as an increase in the withdrawal force following local treatment. These changes reflect the clinical condition in the level as well as in the duration of the response. These data indicate a good resemblance between pig and human skin and suggest that use of these animals in the preclinical phase of developing topical analgesics can, to some extent, release the bottleneck.

Analgesic efficacy of ropivacaine wound infusion after laparoscopic colorectal surgery

Purpose

Local anesthetic wound infusion has been previously investigated in postoperative pain management. However, a limited number of studies have evaluated its use in laparoscopic colorectal surgery. This study aims to evaluate whether ropivacaine wound infusion is effective for postoperative pain management after laparoscopic surgery in patients with colorectal cancer.

Methods

This prospective study included 184 patients who underwent laparoscopic surgery for colorectal cancer between July 2012 and June 2013. The patients were grouped as the combined group (intravenous patient-controlled analgesia [IV-PCA] plus continuous wound infusion with ropivacaine, n = 92) and the PCA group (IV-PCA only, n = 92). Efficacy and safety were assessed in terms of numeric rating scale (NRS) pain score, opioid consumption, postoperative recovery, and complications.

Results

The total quantity of PCA fentanyl was significantly less in the combined group than in the PCA group (P < 0.001). The NRS score of the combined group was not higher than in the PCA group, despite less opioid consumption. There were no differences between groups for postoperative recovery and most complications, including wound complications. However, the rate of nausea and vomiting was significantly lower in the combined group (P = 0.022).

Conclusion

Ropivacaine wound infusion significantly reduced postoperative opioid requirements and the rate of nausea/vomiting. This study showed clinical efficacy of ropivacaine wound infusion for postoperative pain control in colorectal cancer patients undergoing laparoscopic surgery.