Opioid free onco-anesthesia: Is it time to convict opioids? A systematic review of literature

Postoperative opioid-free analgesia in dogs undergoing tibial plateau leveling osteotomy: a feasibility study

Objectives

This study was designed to prospectively evaluate the feasibility of an opioid-free anesthesia protocol and describe the quality of recovery and management of postoperative analgesia in dogs after a tibial plateau leveling osteotomy (TPLO).

Methods

In total, 20 dogs presented for TPLO were included. After premedication with intravenous (IV) medetomidine (0.005-0.007 mg/kg) and midazolam (0.2 mg/kg), the dogs were anesthetized using ketamine (2 mg/kg) and propofol and maintained with isoflurane and ketamine CRI (0.6 mg/kg/h). Sciatic and femoral nerve blocks were performed with bupivacaine 0.5% (0.087 +/- 0.01 and 0.09 +/- 0.02 mL/kg, respectively). Meloxicam (0.2 mg/kg IV) was administered intraoperatively, after osteotomy. Fentanyl (0.002 mg/kg IV) was administered intraoperatively, as rescue analgesia in the case of sustained increase in cardiorespiratory variables. Two pain scores (French 4A-VET and Glasgow short form) were performed at conscious sternal recumbency and 2, 4, 6, 8, 12, and 20 h after extubation and compared to baseline using a Friedman test followed by a Nemenyi post-hoc test. The time taken for the first food intake and urination was reported.

Results

Intraoperative opioid-free anesthesia was feasible in 11 dogs, whereas 9 dogs received fentanyl once during arthrotomy. No opioid postoperative rescue analgesia was required. Food intake occurred within 6 h, and all dogs were discharged after 24 h without any complication.

Conclusion

Total opioid-free postoperative analgesia was achieved in all dogs, with adequate recoveries. Although opioid-free anesthesia was feasible in 55% of the population, a single dose of fentanyl was necessary in 45% of the dogs during arthrotomy.

The Surgical Stress Response and Anesthesia: A Narrative Review

The human physiological response "to stress" includes all metabolic and hormonal changes produced by a traumatic event at the micro or macro cellular levels. The main goal of the body's first response to trauma is to keep physiological homeostasis. The perioperative non-specific adaptation response can sometimes be detrimental and can produce systemic inflammatory response syndrome (SIRS), characterized by hypermetabolism and hyper catabolism. We performed a narrative review consisting of a description of the surgical stress response's categories of changes (neurohormonal and immunological response) followed by reviewing methods found in published studies to modulate the surgical stress response perioperatively. We described various preoperative measures cited in the literature as lowering the burden of surgical trauma. This article revises the anesthetic drugs and techniques that have an impact on the surgical stress response and proven immune-modulatory effects. We also tried to name present knowledge gaps requiring future research. Our review concludes that proper preoperative measures, adequate general anesthetics, multimodal analgesia, early postoperative mobilization, and early enteral nutrition can decrease the stress response to surgery and ease patient recovery. Anesthetics and analgesics used during the perioperative period may modulate the innate and adaptive immune system and inflammatory system, with a consecutive impact on cancer recurrence and long-term outcomes.

Opioid-Sparing Anesthesia Versus Opioid-Free Anesthesia for the Prevention of Postoperative Nausea and Vomiting after Laparoscopic Bariatric Surgery: A Systematic Review and Network Meta-Analysis

BACKGROUND

Patients who undergo laparoscopic bariatric surgery (LBS) are susceptible to postoperative nausea and vomiting (PONV). Opioid-free anesthesia (OFA) or opioid-sparing anesthesia (OSA) protocols have been proposed as solutions; however, differences between the 2 alternative opioid protocols for anesthesia maintenance in obese patients remain uncertain. A network meta-analysis was conducted to compare the impacts of OFA and OSA on PONV.

METHODS

Systematic searches were conducted using Embase, PubMed, MEDLINE, and Cochrane Library databases to identify randomized controlled trials (RCTs) comparing OFA and OSA strategies. After screening according to the inclusion and exclusion criteria, we used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the credibility of the evidence. The main concern of this review was the difference between OFA and OSA in reducing PONV. The primary outcome was any PONV occurrence within 24 hours. Secondary outcomes included postoperative pain intensity, opioid consumption, opioid-related adverse events, and length of hospital stay.

RESULTS

Fifteen RCTs involving 1310 patients were identified for a network meta-analysis from 1776 articles that compared OFA, OSA, and traditional opioid-based anesthesia (OBA) strategies in LBS. Twelve RCTs (80%) with 922 participants (70%) were eligible for the occurrence of PONV. These included 199 (22%) patients who received OFA and 476 (52%) and 247 (27%) patients who received OSA and OBA, respectively. OFA was more effective at reducing PONV (relative risks [RR], 0.6, 95% confidence interval [CI], 0.5-0.9, moderate-quality evidence) compared to OSA. No differences were observed in postoperative pain control or opioid consumption between the OFA and OSA strategies (very low-to high-quality evidence). Notably, OFA is associated with a higher risk of bradycardia than OSA (RR, 2.6, 95% CI, 1.2-5.9, moderate-quality evidence).

CONCLUSIONS

OFA is more effective than OSA in reducing the occurrence of PONV during the early postoperative period of LBS, although it may associate with an increased risk of bradycardia. Patients who received either opioid-alternative strategy demonstrated similar effects in reducing postoperative opioid consumption and alleviating pain intensity.

Opioid-free Anesthesia Protocol on the Early Quality of Recovery after Major Surgery (SOFA Trial): A Randomized Clinical Trial

BACKGROUND

Opioid-free anesthesia is increasingly being adopted to reduce opioid consumption, but its impact on early postoperative recovery after major surgery has not been evaluated in comparative trials. The hypothesis was that an opioid-free anesthesia protocol would enhance the early quality of recovery for patients undergoing scheduled major surgery under general anesthesia.

METHODS

The SOFA study was a monocentric, randomized, controlled, assessor- and patient-blinded clinical trial conducted from July 10, 2021, to February 12, 2022. The eligible population included male and female patients undergoing scheduled major surgery, excluding bone procedures, that typically require opioids for postoperative pain management. Patients in the intervention group received a combination of at least two drugs among ketamine, lidocaine, clonidine, and magnesium sulfate, without opioids for anesthesia. The standard group received opioids. The primary outcome was early postoperative quality of recovery, assessed by Quality of Recovery-15 score at 24 h after surgery. Secondary outcomes were Quality of Recovery-15 at 48 and 72 h after surgery, incidence of chronic pain, and quality of life at 3 months.

RESULTS

Of the 136 randomized patients, 135 were included in the primary analysis (mean age, 45.9 ± 15.7 yr; 116 females [87.2%]; 85 underwent major plastic surgery [63.9%]), with 67 patients in the opioid-free anesthesia group and 68 in the standard group. The mean Quality of Recovery-15 at 24 h was 114.9 ± 15.2 in the opioid-free anesthesia group versus 108.7 ± 18.1 in the standard group (difference, 6.2; 95% CI, 0.4 to 12.0; P = 0.026). Quality of Recovery-15 scores also differed significantly at 48 h (difference, 8.7; 95% CI, 2.9 to 14.5; P = 0.004) and at 72 h (difference, 7.3; 95% CI, 1.6 to 13.0; P = 0.013). There were no differences in other secondary outcomes. No major adverse events were noticed.

CONCLUSIONS

The opioid-free anesthesia protocol improved quality of recovery after major elective surgery in a statistically but not clinically significant manner when compared to standard anesthesia.

EDITOR’S PERSPECTIVE

Are There Any Advantages of the Low Opioid Anaesthesia and Non-Opioid Postoperative Analgesia Protocol: A Clinical Observational Study

Purpose

The methods of perioperative analgesia and pain control have changed. The principle of opioid-based analgesia has been modified to multimodal analgesia, followed by LOA (low opioid anaesthesia) and OFA (opioid-free anaesthesia). The aim was to describe the effects of LOA on nausea, vomiting, and pain control during general anaesthesia and postoperative period after laparoscopic cholecystectomy.

Patients and Methods

The protocol included the study group-40 patients received low-opioid anaesthesia (LOA), and the control group-40 patients received general anaesthesia with opioid analgesia (OA). The scheme of LOA was based on ketamine, lidocaine, magnesium sulfate, paracetamol, and metamizole. The OA was based on standard opioid (fentanyl) administration in induction and maintenance phase due to clinical observation. Postoperative analgesia included 1g of paracetamol and 1g of metamizol intravenously, with a 6-hour interval between doses.

Results

Significant differences in the pain score in the periods of 2-6, 6-12, and 12-24 hours after anaesthesia between the groups were noticed (p < 0.001). Moreover, a significant difference in the frequency of nausea (p = 0.005) and vomiting (p = 0.04) between groups were presented. Nausea occurred in 54.05% of OA group, while in the LOA group, it occurred in a 23.08%. Vomiting occurred in 32.43% of control group, while in the study group, it occurred in 12.82% of patients.

Conclusion

The LOA protocol was more beneficial in reducing nausea and vomiting than the opioid-based method of anaesthesia. The LOA protocol of general anaesthesia during laparoscopic cholecystectomy and non-opioid postoperative analgesia have better outcomes in pain control, as well as nausea and vomiting, and improve postoperative patient comfort. The LOA protocol during anaesthesia and non-opioid postoperative analgesia should be considered in routine practice.

Opioid-free anesthesia versus opioid-based anesthesia in patients undergoing cardiovascular and thoracic surgery: a meta-analysis and systematic review

BACKGROUND

Despite their extensive clinical use, opioids are characterized by several side effects. These complications, coupled with the ongoing opioid epidemic, have favored the rise of opioid-free-anesthesia (OFA). Herein, we perform the first pairwise meta-analysis of clinical outcomes for OFA vs opioid-based anesthesia (OBA) in patients undergoing cardiovascular and thoracic surgery.

METHODS

We comprehensively searched medical databases to identify studies comparing OFA and OBA in patients undergoing cardiovascular or thoracic surgery. Pairwise meta-analysis was performed using the Mantel-Haenszel method. Outcomes were pooled as risk ratios (RR) or standard mean differences (SMD) and their 95% confidence intervals (95% CI).

RESULTS

Our pooled analysis included 919 patients (8 studies), of whom 488 underwent surgery with OBA and 431 with OFA. Among cardiovascular surgery patients, compared to OBA, OFA was associated with significantly reduced post-operative nausea and vomiting (RR, 0.57; P = .042), inotrope need (RR .84, P = .045), and non-invasive ventilation (RR, .54; P = .028). However, no differences were observed for 24hr pain score (SMD, -.35; P = .510) or 48hr morphine equivalent consumption (SMD, -1.09; P = .139). Among thoracic surgery patients, there was no difference between OFA and OBA for any of the explored outcomes, including post-operative nausea and vomiting (RR, 0.41; P = .025).

CONCLUSION

Through the first pooled analysis of OBA vs OFA in a cardiothoracic-exclusive cohort, we found no significant difference in any of the pooled outcomes for thoracic surgery patients. Although limited to 2 cardiovascular surgery studies, OFA was associated with significantly reduced postoperative nausea and vomiting, inotrope need, and non-invasive ventilation in these patients. With growing use of OFA in invasive operations, further studies are needed to assess their efficacy and safety in cardiothoracic patients.

Patient-reported nausea after implementation of an enhanced recovery after surgery protocol for gynae-oncology patients

OBJECTIVES

This study aimed to analyze the adherence to strategies to prevent post-operative nausea and vomiting after implementation of an enhanced recovery after surgery (ERAS) protocol for gynae-oncology patients. Patient-reported nausea before and after ERAS was also studied.

METHODS

This prospective observational study included all patients undergoing laparotomy for a suspicious pelvic mass or confirmed advanced ovarian cancer before (pre-ERAS) and after the implementation of ERAS (post-ERAS) at Oslo University Hospital, Norway. Patients were a priori stratified according to the planned extent of surgery into two cohorts (Cohort 1: Surgery of advanced disease; Cohort 2: Surgery for a suspicious pelvic tumor). Clinical data including baseline characteristics and outcome data were prospectively collected.

RESULTS

A total of 439 patients were included, 243 pre-ERAS and 196 post-ERAS. At baseline, 27% of the patients reported any grade of nausea. In the post-ERAS cohort, statistically significantly more patients received double post-operative nausea and vomiting prophylaxis (64% pre-ERAS vs 84% post-ERAS, p<0.0001). There was no difference in the need for rescue medication (82% pre-ERAS vs 79% post-ERAS; p=0.17) and no statistically significant difference between pre- and post-ERAS or between the surgical cohorts in patient-reported nausea of any grade on day 2. Patients who reported none/mild nausea on day 2 had significantly less peri-operative fluid administered during surgery than those who reported moderate or severe nausea (median 12.5 mL/kg/hour vs 16.5 mL/kg/hour, p=0.045) but, in multivariable analysis, fluid management did not remain significantly associated with nausea.

CONCLUSION

Implementation of an ERAS protocol increased the adherence to post-operative nausea and vomiting prevention guidelines. Nausea, both before and after laparotomy, remains an unmet clinical need of gynae-oncology patients also in an ERAS program. Patient-reported outcome measures warrant further investigation in the evaluation of ERAS.

Can Opioid-Free Anaesthesia Be Personalised? A Narrative Review

Background: A significant amount of evidence suggests that Opioid-Free Anaesthesia (OFA) may provide better outcomes for patients undergoing surgery, sparing patients who are particularly vulnerable to adverse side effects of opioids. However, to what extent personalizing OFA is feasible and beneficial has not been adequately described. Methods: We conducted a narrative literature review aiming to provide a comprehensive understanding of nociception and pain and its context within the field of OFA. Physiological (including monitoring), pharmacological, procedural (type of surgery), genetical and phenotypical (including patients’ conditions) were considered. Results: We did not find any monitoring robustly associated with improved outcomes. However, we found evidence supporting particular OFA indications, such as bariatric and cancer surgery. We found that vulnerable patients may benefit more from OFA, with an interesting field of research in patients suffering from vascular disease. We found a variety of techniques and medications making it impossible to consider OFA as a single technique. Our findings suggest that a vast field of research remains unexplored. In particular, a deeper understanding of nociception with an interest in its genetic and acquired contributors would be an excellent starting point paving the way for personalised OFA. Conclusion: Recent developments in OFA may present a more holistic approach, challenging the use of opioids. Understanding better nociception, given the variety of OFA techniques, may help to maximize their potential in different contexts and potential indications.

Cervical Endocrine Surgery With a Novel Opioid-Limited Perioperative Protocol

BACKGROUND

Recent studies have demonstrated that patients undergoing cervical endocrine surgery could be comfortably discharged with minimal opioid analgesia. However, no study to date has examined the efficacy of limiting administration of opioids intraoperatively. We have developed a novel protocol for patients undergoing cervical endocrine surgery that eliminates perioperative opioids. We sought to determine the efficacy of this protocol and its impact on opioid use at discharge.

METHODS

We conducted a prospective opt-in opioid-limited surgery program study to opioid-naive patients scheduled for cervical endocrine surgery beginning in August 2019. Postoperatively, nonopioid analgesia was encouraged, but patients were also given a low dose prescription for opioids at discharge. Patients were then matched with 2 retrospective control groups, patients from 2014-2016 and 2017-2018, in order to account for increased public awareness of opioid-prescribing patterns. Primary end points included perioperative opioid use. Secondary end points included postoperative pain scores and complications.

RESULTS

218 patients underwent cervical endocrine surgery with our opioid-limited protocol between August 2019 and February 2020. Nine patients received opioids intraoperatively (4%) and 109 (50%) filled their opioid prescriptions at discharge. Compared to retrospective control groups, the average oral morphine equivalents (OME) administered intraoperatively and prescribed postoperatively were significantly lower (P < .0001). Pain scores and complication rates were similar in all groups (P = .7247).

DISCUSSION

Our novel opioid-limited surgery protocol used in conjunction with preoperative counseling is an effective approach for pain control in patients undergoing cervical endocrine surgery and limits opioid exposure throughout the perioperative period.

A retrospective investigation of the relationship between neuroblastoma response to anti-GD2 monoclonal antibodies and exposure to opioids for pain management

OBJECTIVE

Recent increased awareness and research studies reflect possible associations between opioid exposure and cancer outcomes. Children with neuroblastoma (NB) often require opioid treatment for pain. However, associations between tumor response to chemotherapy and opioid exposure have not been investigated in clinical settings.

METHODS

This is a single-institution retrospective review of patients with NB treated between 2013 and 2016. We evaluated opioid consumption quantified in morphine equivalent doses (mg/kg) based on nurse- or patient-controlled analgesia during antibody infusions. We also analyzed their associations with change in primary tumor volume and total tumor burden.

RESULTS

Of 42 patients given opioids for pain related to anti-disialoganglioside monoclonal antibodies (anti-GD2 mAb), data completion was achieved for 36, and details of statistical analyses were entered. Median total weight-based morphine equivalent (over 8 days) was 4.71 mg/kg (interquartile range 3.49-7.96). We found a statistically insignificant weak negative relationship between total weight-based morphine equivalents and tumor volume ratio (correlation coefficient -.0103, p-value .9525) and a statistically insignificant weak positive relationship between total weight-based morphine equivalent and Curie score ratio (correlation coefficient .1096, p-value .5247).

CONCLUSION

Our study found no statistically significant correlation between opioid consumption and natural killer (NK) cell-mediated killing of NB cells as measured by effects on tumor volume/tumor load.

The effect of opioid-free anesthesia protocol on the early quality of recovery after major surgery (SOFA trial): study protocol for a prospective, monocentric, randomized, single-blinded trial

Background

Since the 2000s, opioid-free anesthesia (OFA) protocols have been spreading worldwide in anesthesia daily practice. These protocols avoid using opioid drugs during anesthesia to prevent short- and long-term opioid side effects while ensuring adequate analgesic control and optimizing postoperative recovery. Proofs of the effect of OFA protocol on optimizing postoperative recovery are still scarce. The study aims to compare the effects of an OFA protocol versus standard anesthesia protocol on the early quality of postoperative recovery (QoR) from major surgeries.

Methods

The SOFA trial is a prospective, randomized, parallel, single-blind, monocentric study. Patients (n = 140) scheduled for major plastic, visceral, urologic, gynecologic, or ear, nose, and throat (ENT) surgeries will be allocated to one of the two groups. The study group (OFA group) will receive a combination of clonidine, magnesium sulfate, ketamine, and lidocaine. The control group will receive a standard anesthesia protocol based on opioid use. Both groups will receive others standard practices for general anesthesia and perioperative care. The primary outcome measure is the QoR-15 value assessed at 24 h after surgery. Postoperative data such as pain intensity, the incidence of postoperative complication, and opioid consumption will be recorded. We will also collect adverse events that may be related to the anesthetic protocol. Three months after surgery, the incidence of chronic pain and the quality of life will be evaluated by phone interview.

Discussion

This will be the first study powered to evaluate the effect of OFA versus a standard anesthesia protocol using opioids on global postoperative recovery after a wide range of major surgeries. The SOFA trial will also provide findings concerning the OFA impact on chronic pain incidence and long-term patient quality of life.

Trial registration

ClinicalTrials.gov NCT04797312. Registered on 15 March 2021

Tissue Regeneration: The Dark Side of Opioids

Opioids are regarded as among the most effective analgesic drugs and their use for the management of pain is considered standard of care. Despite their systematic administration in the peri-operative period, their impact on tissue repair has been studied mainly in the context of scar healing and is only beginning to be documented in the context of true tissue regeneration. Indeed, in mammals, growing evidence shows that opioids direct tissue repair towards scar healing, with a loss of tissue function, instead of the regenerative process that allows for recovery of both the morphology and function of tissue. Here, we review recent studies that highlight how opioids may prevent a regenerative process by silencing nociceptive nerve activity and a powerful anti-inflammatory effect. These data open up new perspectives for inducing tissue regeneration and argue for opioid-restricted strategies for managing pain associated with tissue injury.

Perioperative Opioid Administration

Opioids form an important component of general anesthesia and perioperative analgesia. Discharge opioid prescriptions are identified as a contributor for persistent opioid use and diversion. In parallel, there is increased enthusiasm to advocate opioid-free strategies, which include a combination of known analgesics and adjuvants, many of which are in the form of continuous infusions. This article critically reviews perioperative opioid use, especially in view of opioid-sparing versus opioid-free strategies. The data indicate that opioid-free strategies, however noble in their cause, do not fully acknowledge the limitations and gaps within the existing evidence and clinical practice considerations. Moreover, they do not allow analgesic titration based on patient needs; are unclear about optimal components and their role in different surgical settings and perioperative phases; and do not serve to decrease the risk of persistent opioid use, thereby distracting us from optimizing pain and minimizing realistic long-term harms.

Opioids and premature biochemical recurrence of prostate cancer: a randomised prospective clinical trial

BACKGROUND

Prostate cancer is one of the most prevalent neoplasms in male patients, and surgery is the main treatment. Opioids can have immune modulating effects, but their relation to cancer recurrence is unclear. We evaluated whether opioids used during prostatectomy can affect biochemical recurrence-free survival.

METHODS

We randomised 146 patients with prostate cancer scheduled for prostatectomy into opioid-free anaesthesia or opioid-based anaesthesia groups. Baseline characteristics, perioperative data, and level of prostate-specific antigen every 6 months for 2 yr after surgery were recorded. Prostate-specific antigen >0.2 ng ml^-1 was considered biochemical recurrence. A survival analysis compared time with biochemical recurrence between the groups, and a Cox regression was modelled to evaluate which variables affect biochemical recurrence-free survival.

RESULTS

We observed 31 biochemical recurrence events: 17 in the opioid-free anaesthesia group and 14 in the opioid-based anaesthesia group. Biochemical recurrence-free survival was not statistically different between groups (P=0.54). Cox regression revealed that biochemical recurrence-free survival was shorter in cases of obesity (hazard ratio [HR] 1.63, confidence interval [CI] 0.16-3.10; p=0.03), high D'Amico risk (HR 1.58, CI 0.35-2.81; P=0.012), laparoscopic surgery (HR 1.6, CI 0.38-2.84; P=0.01), stage 3 tumour pathology (HR 1.60, CI 0.20-299) and N1 status (HR 1.34, CI 0.28-2.41), and positive surgical margins (HR 1.37, CI 0.50-2.24; P=0.002). The anaesthesia technique did not affect time to biochemical recurrence (HR -1.03, CI -2.65-0.49; P=0.18).

CONCLUSIONS

Intraoperative opioid use did not modify biochemical recurrence rates and biochemical recurrence-free survival in patients with intermediate and high D'Amico risk prostate cancer undergoing radical prostatectomy.

CLINICAL TRIAL REGISTRATION

NCT03212456.

Is the Use of Opioids Safe after Primary Cleft Palate Repair? A Systematic Review

Pharmacologic treatment of postoperative pain after cleft palate repair includes opioids and nonopioid analgesics, nerve blocks, and local anesthetic infiltration. Use of opioids in infants has concerns regarding sedation, risk of aspiration, respiratory depression, and respiratory distress. The main objective of this review was to analyze information available on the safety of the use of opioids during perioperative management of pain related to primary cleft palate repair in published studies.

Methods

A systematic review of the literature for studies published until March 2020 was performed to evaluate the safety of opioid drugs during primary cleft palate repair pain management. The authors chose the following MesH terms for this systematic review: cleft lip and palate AND opioids AND pain management. The investigators performed a systematic literature search using the Pubmed/MEDLINE, Embase, Web of Science, and Cochrane Library databases.

Results

After a literature search resulting in 70 identified studies, 9 were qualified for the final analysis, which included 772 patients. There was a high level of evidence in the selected studies according to the Oxford CEBM Level of Evidence classification and GRADE scale. The most common adverse event reported was postoperative nausea and vomiting (from 5% to 25%). Episodes of oxygen desaturation have been reported from 2.5% to 7.4% of the studied patients.

Conclusion

s: Definitive conclusions about the safety of opioid drugs during primary cleft palate repair pain management cannot be drawn. Vomiting and oxygen desaturation have been associated with the use of opioids in the studied population.

The effect of anesthesia on the magnitude of the postoperative systemic inflammatory response in patients undergoing elective surgery for colorectal cancer in the context of an enhanced recovery pathway: A prospective cohort study

There are reports that the use of regional anesthesia (RA) may be associated with better perioperative surgical stress response in cancer patients compared with general anesthetics (GA). However, the role of anesthesia on the magnitude of the postoperative systemic inflammatory response (SIR) in colorectal cancer patients, within an enhanced recovery pathway (ERP), is not clear.The aim of the present study was to examine the effect of anesthesia, within an enhanced recovery pathway, on the magnitude of the postoperative SIR in patients undergoing elective surgery for colorectal cancer.Database of 507 patients who underwent elective open or laparoscopic colorectal cancer surgery between 2015 and 2019 at a single center was studied. The anesthetic technique used was categorized into either GA or GA + RA using a prospective proforma. The relationship between each anesthetic technique and perioperative clinicopathological characteristics was examined using binary logistic regression analysis.The majority of patients were male (54%), younger than 65 years (41%), either normal or overweight (64%), and were nonsmokers (47%). Also, the majority of patients underwent open surgery (60%) and received mainly general + regional anesthetic technique (80%). On univariate analysis, GA + RA was associated with a lower day 4 CRP (≤150/>150 mg/L) concentration. On day 4, postoperative CRP was associated with anesthetic technique [odds ratio (OR) 0.58; confidence interval (CI) 0.31-1.07; P = .086], age (OR 0.70; CI 0.50-0.98; P = .043), sex (OR 1.15; CI 0.95-2.52; P = .074), smoking (OR 1.57; CI 1.13-2.19; P = .006), preoperative mGPS (OR 1.55; CI 1.15-2.10; P = .004), and preoperative dexamethasone (OR 0.70; CI 0.47-1.03; P = .072). On multivariate analysis, day 4 postoperative CRP was independently associated with anesthetic technique (OR 0.56; CI 0.32-0.97; P = .039), age (OR 0.74; CI 0.55-0.99; P = .045), smoking (OR 1.58; CI 1.18-2.12; P = .002), preoperative mGPS (OR 1.41; CI 1.08-1.84; P = .012), and preoperative dexamethasone (OR 0.68; CI 0.50-0.92; P = .014).There was a modest but an independent association between RA and a lower magnitude of the postoperative SIR. Future work is warranted with multicenter RCT to precisely clarify the relationship between anesthesia and the magnitude of the postoperative SIR.