Opioid free anesthesia: evidence for short and long-term outcome

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Comparison of postoperative analgesia effects between subcostal anterior quadratus lumborum block and transversus abdominis plane block in bariatric surgery: a prospective randomized controlled study

BACKGROUND

Currently, the prevalence of obesity is on the rise annually. Bariatric surgery stands out as the most efficacious approach for addressing obesity. Obese patients are more prone to experience moderate to severe pain after surgery due to lower pain thresholds. Regional block, as an important component of multimodal analgesia in bariatric surgery, is crucial in reducing opioid consumption and alleviating postoperative pain in patients undergoing bariatric surgery. Transversus abdominis plane block (TAPB) has gained widespread utilization in bariatric surgery; however, its limitation of inadequate reduction of visceral pain in obese patients remains a significant concern. Therefore, it is imperative to explore new and more efficient strategies for analgesia. Quadratus lumborum block (QLB) has emerged as a popular nerve block in recent years, frequently utilized in conjunction with general anesthesia for abdominal surgery. In the cadaver study of QLB, it was confirmed that the dye level could reach up to T6 when using the subcostal anterior quadratus lumborum muscle approach, which could effectively reduce the incision pain and visceral pain of bariatric surgery patients during the perioperative period. However, there is currently a lack of research on the use of subcostal anterior QLB in patients undergoing bariatric surgery. Our study aims to investigate whether subcostal anterior QLB can provide superior perioperative analgesic efficacy for bariatric surgery under general anesthesia compared to TAPB, leading to reduced postoperative opioid consumption and a lower incidence of postoperative nausea and vomiting (PONV).

METHODS AND DESIGN

This study is a prospective, randomized controlled trial aiming to recruit 66 patients undergoing bariatric surgery. The participants will be randomly allocated into two groups in a 1:1 ratio: subcostal anterior QLB group (n = 33) and TAPB group (n = 33). The study aims to investigate the efficacy of subcostal anterior QLB and TAPB in obese patients who are scheduled to undergo bariatric surgery. Our primary outcome is to observe the amount of opioids used in the two groups 24 h after operation. The secondary outcomes included VAS of pain during rest/activity after operation, the type and dose of additional analgesics, the occurrence and severity of PONV, the type and dose of additional antiemetic drugs, postoperative anesthesia care unit (PACU) time, time of first postoperative exhaust, time to first out of bed activity, time to first liquid diet and postoperative admission days.

DISCUSSION

Opioid analgesics are prone to causing adverse reactions such as nausea, vomiting, and respiratory depression, especially in obese patients. Multimodal analgesia, including nerve block, can effectively reduce the dose of opioids and alleviate their adverse effects. Currently, TAPB is the most prevalent nerve block analgesia method for abdominal surgery. Recent studies have indicated that subcostal anterior QLB offers advantages over TAPB, including a wider block plane, faster onset, and longer maintenance time. It is not clear which of the two nerve block analgesia techniques is better for postoperative analgesia in patients undergoing bariatric surgery. Our objective in this investigation is to elucidate the superior method between TAPB and subcostal anterior QLB for postoperative pain management in bariatric surgery.

TRIAL REGISTRATION

ChiCTR ChiCTR2300070556. Registered on 17 April 2023.

Opioid-Free Anesthesia in a Young Female Undergoing Emergency Videolaparoscopic Appendectomy: A Case Report

Opioids are one of the main classes of drugs used in anesthesia, both for the intraoperative and postoperative period, for a multitude of surgical procedures. In recent years, anesthetic techniques have been developed that reduce or avoid the use of opioids and their side effects. One of these is opioid-free anesthesia, which does not involve the use of opioid drugs in the intraoperative period. In this case report, we used this anesthetic technique for an emergency videolaparoscopic appendectomy for a young woman in a state of sepsis with a history of previous surgery for the removal of a voluminous ovarian cyst.

Comparative study between remifentanil (or fentanyl) and dexmedetomidine for the analgesia of rhinoplasty: A meta-analysis of randomized controlled trials

BACKGROUND

Remifentanil (or fentanyl) and dexmedetomidine may have some potential to improve the analgesia of rhinoplasty, and this meta-analysis aims to compare their efficacy for the analgesia of rhinoplasty.

METHODS

PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases were systematically searched, and we included randomized controlled trials (RCTs) assessing the analgesic effect of remifentanil (or fentanyl) versus dexmedetomidine for rhinoplasty.

RESULTS

Four RCTs were finally included in the meta-analysis. In patients undergoing rhinoplasty, remifentanil (or fentanyl) infusion and dexmedetomidine infusion resulted in similar good patient satisfaction (odd ratio [OR] = 2.71; 95% confidence interval [CI] = 0.63 to 11.64; P = .18), good surgeon satisfaction (OR = 1.68; 95% CI = 0.02 to 181.40; P = .83), extubation time (mean difference [MD] = 7.56; 95% CI = -11.00 to 26.12; P = .42), recovery time (MD = -2.25; 95% CI = -23.41 to 18.91; P = .83), additional analgesic requirement (OR = 0.16; 95% CI = 0 to 8.65; P = .37) and adverse events (OR = 8.50; 95% CI = 0.47 to 153.30; P = .15).

CONCLUSIONS

Remifentanil (or fentanyl) and dexmedetomidine may have comparable analgesia for patients undergoing rhinoplasty.

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.

Anesthesia and cancer recurrence: a narrative review

Cancer is a leading cause of death worldwide. With the increasingly aging population, the number of emerging cancer cases is expected to increase markedly in the foreseeable future. Surgical resection with adjuvant therapy is the best available option for the potential cure of many solid tumors; thus, approximately 80% of patients with cancer undergo at least one surgical procedure during their disease. Agents used in general anesthesia can modulate cytokine release, transcription factors, and/or oncogenes. This can affect host immunity and the capability of cancer cells to survive and migrate, not only during surgery but for up to several weeks after surgery. However, it remains unknown whether exposure to anesthetic agents affects cancer recurrence or metastasis. This review explores the current literature to explain whether and how the choice of anesthetic and perioperative medication affect cancer surgery outcomes.

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.

TEDOFA Trial Study Protocol: A Prospective Double-Blind, Randomized, Controlled Clinical Trial Comparing Opioid-Free versus Opioid Anesthesia on the Quality of Postoperative Recovery and Chronic Pain in Patients Receiving Thoracoscopic Surgery

Introduction

Seeking effective multimodal analgesia and anesthetic regimen is the basis for the success of ERAS. Opioid-free anesthesia (OFA) is a multimodal anesthesia associating hypnotics, N-methyl-D-aspartate (NMDA) antagonists, local anesthetics, anti-inflammatory drugs and α-2 agonists. Although previous studies have confirmed that OFA is safe and feasible for VATS surgery, there is great heterogeneity in how to select and combine anti-harm drugs to replace opioids. We hypothesized that the reduced opioid use during and after surgery allowed by OFA compared with standard of care will be associated with a reduction of postoperative opioid-related adverse events and an improvement in the quality of rehabilitation of patients after partial VATS lung resection.

Methods/Analysis

The TEDOFA Study is a prospective double-blind, randomized, controlled clinical trial with a concealed allocation of patients scheduled to undergo elective partial VATS pneumonectomy 1:1 to receive either a standard anesthesia protocol or an OFA. A total of 146 patients were recruited in the study. Primary endpoint was the 15-item recovery quality scale (QoR-15) at 24 hours after surgery.

Ethics and Dissemination

This trial has been approved by the Institutional Review Board of Beijing Friendship Hospital of China Capital University. The TEDOFA trial study protocol was approved on 27 February 2023. The trial started recruiting patients after registered on the Chinese Clinical Trial Registry.

Trial Registration Number

ChiCTR2300069210; Pre-results.

Opioid-free anaesthesia reduces postoperative nausea and vomiting after thoracoscopic lung resection: a randomised controlled trial

BACKGROUND

Intraoperative opioid use has a positive relationship with postoperative nausea and vomiting (PONV), and opioid-free anaesthesia (OFA) might reduce PONV. We investigated whether OFA compared with opioid-based anaesthesia would reduce PONV during the first 2 postoperative days among patients undergoing thoracoscopic lung resection.

METHODS

In this randomised controlled trial, 120 adult patients were randomly assigned (1:1, stratified by sex) to receive either OFA with esketamine, dexmedetomidine, and sevoflurane, or opioid-based anaesthesia with sufentanil and sevoflurane. A surgical pleth index (SPI) of 20-50 was applied for intraoperative analgesia provision. All subjects received PONV prophylaxis (dexamethasone and ondansetron) and multimodal analgesia (flurbiprofen axetil, ropivacaine wound infiltration, and patient-controlled sufentanil). The primary outcome was the occurrence of PONV during the first 48 h after surgery.

RESULTS

The median age was 53 yr and 66.7% were female. Compared with opioid-based anaesthesia, OFA significantly reduced the incidence of PONV (15% vs 31.7%; odds ratio [OR]=0.38, 95% confidence interval [CI], 0.16-0.91; number needed to treat, 6; P=0.031). Secondary and safety outcomes were comparable between groups, except that OFA led to a lower rate of vomiting (OR=0.23, 95% CI, 0.08-0.77) and a longer length of PACU stay (median difference=15.5 min, 95% CI, 10-20 min). The effects of OFA on PONV did not differ in the prespecified subgroups of sex, smoking status, and PONV risk scores.

CONCLUSIONS

In the context of PONV prophylaxis and multimodal analgesia, SPI-guided opioid-free anaesthesia halved the incidence of PONV after thoracoscopic lung resection, although it was associated with a longer stay in the PACU.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200059710).

How to Modulate Peripheral and Central Nervous System to Treat Acute Postoperative Pain and Prevent Pain Persistence

Chronic postoperative pain (CPSP) is a major issue after surgery, which may impact on patient's quality of life. Traditionally, CPSP is believed to rely on maladaptive hyperalgesia and risk factors have been identified that predispose to CPSP, including acute postoperative pain. Despite new models of prediction are emerging, acute pain is still a modifiable factor that can be challenged with perioperative analgesic strategies. In this review we present the issue of CPSP, focusing on molecular mechanism underlying the development of acute and chronic hyperalgesia. Also, we focus on how perioperative strategies can impact directly or indirectly (by reducing postoperative pain intensity) on the development of CPSP.

Opioid-free anesthesia reduces the severity of acute postoperative motion-induced pain and patient-controlled epidural analgesia-related adverse events in lung surgery: randomized clinical trial

Background

Opioids have been used as pain relievers for thousands of years. However, they may also cause undesirable side effects. We therefore performed this study to compare the effect of opioid-free anesthesia (OFA) versus opioid-sparing anesthesia (OSA) on postoperative pain and patient-controlled epidural analgesia (PCEA)-related events.

Methods

This is a single center randomized clinical trial that was recruited patients aged from 18 to 70 years who received video-assisted lung surgery between October 2021 and February 2022. Participants were 1:1 randomly assigned to OFA or OSA. Patients in the OFA group received propofol, rocuronium, esmolol, lidocaine, and magnesium sulfate intravenously with epidural ropivacaine. Patients in the OSA group received propofol, rocuronium, remifentanil, and sufentanil intravenously with epidural hydromorphone and ropivacaine.

Results

A total number of 124 patients were randomly allocated to the OFA or OSA group. In the OFA group, the severity of pain during coughs on the first postoperative days (PODs; VAS score 1.88 ± 0.88 vs. 2.16 ± 1.1, p = 0.044) was significantly lower than that in the OSA group. The total ratio of PCEA-related adverse events in the OFA group [11 (19.6%) vs. 26 (47.3%), p = 0.003] was significantly lower than in the OSA group.

Conclusion

OFA in patients who received video-assisted lung surgery led to lower severity of acute postoperative motion-induced pain and fewer PCEA-related adverse events on the first POD than in the patients in the OSA group.

Clinical trial registration

clinicaltrials.gov, identifier (NCT05063396).

Opioid-Free Anesthesia for Pain Relief After Laparoscopic Cholecystectomy: A Prospective Randomized Controlled Trial

Purpose

To compare the efficacies of opioid-free anesthesia (OFA) and opioid-based anesthesia (OBA) in laparoscopic cholecystectomy (LC).

Patients and Methods

A total of 150 patients who underwent 3-port LC procedures were randomly divided into an OFA group with esketamine, dexmedetomidine and lidocaine intravenous combined with local anesthetic incision infiltration or an OBA group with remifentanil combined with local anesthetic incision infiltration. The primary outcome was the consumption of rescue analgesics within 24 hrs after surgery. Secondary outcomes included time to LMA removal, time to orientation recovery, time to unassisted walking, sleep quality on the night of surgery, time to first flatus, hemodynamics during induction of general anesthesia, postoperative pain level on the visual analog scale (VAS), incidence of postoperative nausea and vomiting (PONV) and global satisfaction score (GSS) within 24 hrs after surgery.

Results

Both the consumption of rescue analgesics and the time to first flatus in the OFA group were significantly lower than those in the OBA group (P < 0.001 and P = 0.029, respectively). However, the time to LMA removal and the time to orientation recovery were significantly longer in the OFA group than in the OBA group (P < 0.001). In addition, the VAS scores at 2 hrs and 8 hrs after surgery and HR at laryngeal mask airway insertion in the OFA group were significantly lower than those in the OBA group (P = 0.002 and P = 0.001, and P =0.016, respectively).

Conclusion

OFA may be beneficial for patients undergoing LC in that it could decrease the dosage of postoperative analgesics and pain intensity and even shorten the time to first flatus after surgery.

Opioid Free Total Intravenous Anesthesia With Dexmedetomidine-Esketamine-Lidocaine for Patients Undergoing Lumpectomy

Background

The aim of the study was to evaluate the feasibility of the opioid-free anesthesia (OFA) technique with dexmedetomidine, esketamine, and lidocaine among patients diagnosed with benign breast mass and scheduled for lumpectomy.

Methods

We enrolled 80 female patients who were aged from 18 to 60 years, graded with American Society of Anesthesiologists physical status I or II, diagnosed with benign breast mass, and scheduled for lumpectomy. These patients were randomly treated with OFA or opioid-based anesthesia (OBA). Dexmedetomidine-esketamine-lidocaine and sufentanil-remifentanil were administered in OFA and OBA group, respectively. We mainly compared the analgesic efficacy of OFA and OBA technique, as well as intraoperative hemodynamics, the quality of recovery, and satisfaction score of patients.

Results

There was no significant difference between the two groups with regard to visual analogue scale (VAS) score at 2, 12, and 24 h after extubation. However, the time to first rescue analgesic was prolonged in OFA group than that in OFB group (6.18 ± 1.00 min vs. 7.40 ± 0.92 min, P = 0.000). Further, mean arterial pressure and heart rate at T0 (entering operating room), T1 (before anesthesia induction), T2 (immediately after intubation), T3, T4, and T5 (1, 5, and 10 min after surgical incision, respectively) were significantly higher in OFA group than that in OBA group. Incidence of hypotension and bradycardia was lower in OFA group. Consistently, fewer patients in OFA group consumed atropine (8% vs. 32%, P = 0.019) and ephedrine (5% vs. 38%, P = 0.001) compared to OBA group. Furthermore, patients in OFA group had a longer awakening time (7.14 ± 2.63 min vs. 4.54 ± 1.14 min, P = 0.000) and recovery time of orientation (11.76 ± 3.15 min vs. 6.92 ± 1.19 min, P = 0.000). Fewer patients in the OFA group experienced postoperative nausea and vomiting (PONV) (11% vs. 51%, P = 0.000) and consumed ondansetron (5% vs. 35%, P = 0.003) compared to OBA group. And patients in OFA group had a higher satisfaction score than those in OBA group (9 (8 - 9) vs. 7 (7 - 8), P = 0.000).

Conclusion

For patients undergoing lumpectomy, OFA technique with dexmedetomidine-esketamine-lidocaine showed a better postoperative analgesic efficacy, a more stable hemodynamics, and a lower incidence of PONV. However, such advantage of OFA technique should be weighed against a longer awakening time and recovery time of orientation in clinical practice.

Perioperative pain management in thoracic surgery: A survey of practices in Australia and New Zealand

There are few data on current trends in pain management for thoracic surgery in Australia and New Zealand. Several new regional analgesia techniques have been introduced for these operations in the past few years. Our survey aimed to assess current practice and perceptions towards various modalities of pain management for thoracic surgery among anaesthetists in Australia and New Zealand. A 22-question electronic survey was developed and distributed in 2020 with the assistance of the Australian and New Zealand College of Anaesthetists Cardiac Thoracic Vascular and Perfusion Special Interest Group. The survey focused on four key domains-demographics, general pain management, operative technique, and postoperative approach. Of the 696 invitations, 165 complete responses were obtained, for a response rate of 24%. Most respondents reported a trend away from the historical standard of thoracic epidural analgesia, with a preference towards non-neuraxial regional analgesia techniques. If representative of anaesthetists in Australia and New Zealand more widely, this trend may result in less exposure of junior anaesthetists to the insertion and management of thoracic epidurals, potentially resulting in reduced familiarity and confidence in the technique. Furthermore, it demonstrates a notable reliance on surgically or intraoperatively placed paravertebral catheters as the primary analgesic modality, and suggests the need for future studies assessing the optimal method of catheter insertion and perioperative management. It also gives some insight into the current opinion and practice of the respondents with regard to formalised enhanced recovery after surgery pathways, acute pain services, opioid-free anaesthesia, and current medication selection.

Feasibility of the pupillary pain index as a guide for depth of analgesia during opioid-sparing anesthesia with continuous infusion of dexmedetomidine

BACKGROUND

The pupillary dilation reflex (PDR) is an objective indicator of analgesic levels in anesthetized patients. Through measurement of the PDR during increasing tetanic stimulation (10-60 mA), it is possible to obtain the pupillary pain index (PPI), a score that assesses the level of analgesia.

OBJECTIVES

The depth of analgesia during opioid-sparing anesthesia (OSA) with continuous infusion of dexmedetomidine in addition to general anesthesia was assessed.

DESIGN

Observational prospective feasibility pilot study SETTING: This study was performed in the operating rooms of the Spedali Civili University-affiliated hospital of Brescia, Italy.

PATIENTS

Forty-five adults who underwent elective open (5-cm incision) surgery under general anesthesia (78% inhalation anesthesia), from Feb. 18th to Aug. 1st, 2019, were enrolled. Exclusion criteria were as follows: implanted pacemaker or ICD, ophthalmological comorbidities, chronic opioid use, peripheral neuropathy, other adjuvant drugs, epidural analgesia, or locoregional block.

MAIN OUTCOME MEASURES

The first aim was to verify the feasibility of applying a study protocol to evaluate the depth of analgesia during intraoperative dexmedetomidine administration using an instrumental pupillary evaluation. The secondary outcome was to evaluate appropriate analgesia, drug dosage, anesthesia depth, heart rate, blood pressure, transient side effects, postoperative nausea and vomiting (PONV), and pain numerical rating scale (NRS) score.

RESULTS

Thirty out of 50 patients (60%) treated with dexmedetomidine during the study period were included in the DEX group (8 males, age 42 ± 13 years, BMI 45 ± 8), and 15 other patients were included in the N-DEX group (8 males, age 62 ± 13 years, BMI 26 ± 6). Patients who underwent bariatric, abdominal, or plastic surgery were enrolled. At least 3 pupillary evaluations were taken for each patient. PPI ≤ 3 was observed in 97% of patients in the DEX group and 53% in the N-DEX group. Additionally, the DEX group received less than half the remifentanil dose than the N-DEX group (0.13 ± 0.07 vs 0.3 ± 0.11 mcg kg-1 min-1). The average dose of dexmedetomidine administered was 0.17 ± 0.08 mcg kg-1 h-1.

CONCLUSION

The feasibility of applying the protocol was verified. An OSA strategy involving dexmedetomidine may be associated with improved analgesic stability: a randomized controlled trial is necessary to verify this hypothesis.

TRIAL REGISTRATION

Trial.gov registration number: NCT05785273.

Prolonged continuous wound infusion of local anesthetic and steroid after major abdominal surgery to reduce opioid consumption: a randomized, double-blind trial

BACKGROUND

Continuous wound infusion (CWI) is effective for post-operative pain management, but the effect of prolonged infusions and the use of steroids in the infused mixture have never been addressed. We investigate the effect of prolonged CWI with ropivacaine 0.2% (R) over seven days and methylprednisolone (Mp) 1 mg/kg infused in the wound in the first 24 hours.

METHODS

This is a randomized, double blind, phase III trial (RCT) in major abdominal surgery with laparotomy. After a 24-hours pre-peritoneal CWI of R-Mp, patients were randomized to receive either R-Mp or placebo for the next 24 hours. Then, patient-controlled CWI with only ropivacaine 0.2% or placebo (according to the randomization group) was planned between 48 hours and seven days after surgery. Morphine equivalents at seven days were analyzed, together with any catheter- or drug-related side effect and PPSP at 3 months.

RESULTS

We enrolled 120 patients (63 in the CWI group, 57 in the placebo group). Prolonged CWI did not reduce opioid consumption in the first seven postoperative days (P=0.08). CWI was associated with reduced consumption of non-opioid analgesics (P=0.03). Most of the patients continued to require bolus in the surgical wound beyond 48 hours. PPSP prevalence was not different between groups.

CONCLUSIONS

Prolonged infusion with R-Mp is safe and effective but did not reduce opioid consumption in the seven days after surgery or PPSP prevalence.

Opioid-Free Anesthesia and Postoperative Outcomes in Cancer Surgery: A Systematic Review

BACKGROUND

Surgery is an essential component of the treatment of solid tumors, but the perioperative course can be complicated by different factors (including anesthesia). Opioid-free anesthesia (OFA) may mitigate adverse outcomes of opioid-based anesthesia (OBA), but major questions remain on the actual impact in terms of analgesia and the improvement of surgical outcomes. To address this issue, we present a systematic review to evaluate the efficacy of OFA compared to OBA in the specific subset of cancer patients undergoing surgery.

METHODS

following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA), we searched MEDLINE, Embase and the Cochrane CENTRAL Library to include randomized controlled trials (RCTs) on adults undergoing oncological surgery, comparing OFA and OBA up to March 2022. Additional papers were added from the reference lists of identified sources. Papers were manually reviewed by two independent authors to ascertain eligibility and subsequent inclusion in qualitative analysis.

RESULTS

only two studies were eligible according to inclusion criteria. It was not possible to perform any meta-analysis. The two studies included patients undergoing prostate and gynecologic surgery on 177 patients, with significant heterogeneity in the outcomes.

CONCLUSIONS

randomized controlled trial specifically addressed to cancer patients are lacking. A knowledge gap exists, neither confirming nor rejecting the capacity of OFA to improve early postoperative outcomes in cancer surgery. Long-term consequences on specific oncological outcomes are far from being elucidated. We expect a growing body of literature in the coming years. Further studies are required with homogeneous methodology and endpoints.

Is esketamine-based opioid-free anesthesia more superior for postoperative analgesia in obstructive sleep apnea patients undergoing bariatric surgery? A study protocol

INTRODUCTION

Opioid-free anesthesia (OFA) can certainly prevent nausea and vomiting after bariatric surgery (BS), but its postoperative analgesic effect is still controversial. Obstructive sleep apnea (OSA) is a prominent feature of morbid obesity in BS and accounts for a very high proportion, which significantly increases the difficulty of patients' airway management. Those patients will be more representative and highlight the advantages of OFA. It is not clear whether esketamine can play a more prominent role in OFA for postoperative analgesia. Therefore, this study aims to explore the postoperative analgesic effect of esketamine-based OFA on BS patients with OSA.

METHODS AND ANALYSIS

This single-center, prospective, randomized, controlled, single-blind study is planned to recruit 48 participants to undergo BS from May 2022 to April 2023. Patients will be randomly assigned to the OFA group and opioid-based anesthesia (OBA) group in a ratio of 1:1. The primary outcome is the Numeric Rating Scale (NRS) at different times postoperatively. Secondary outcomes include analgesic intake, the incidence and severity of postoperative nausea and vomiting (PONV), Leiden Surgical Rating Scale (L-SRS), postoperative agitation and chills, PACU stay time, EuroQol five-dimensional questionnaire (EQ-5D), length of hospital stay, intraoperative awareness, and hemodynamically unstable treatments.

DISCUSSION

The results of this study may explain the analgesic effect of esketamine-based OFA on patients undergoing BS combined with OSA, and provide evidence and insight for perioperative pain management.

ETHICS AND DISSEMINATION

This study is initiated by the Ethics Committee of The First Affiliated Hospital of Shandong First Medical University [YXLL-KY-2022(035)]. The trial results will be published in peer-reviewed journals and at conferences.

CLINICAL TRIAL REGISTRATION

[https://clinicaltrials.gov/ct2/show/NCT05386979], identifier [NCT05386979].

The Effect of Opioid-Free Anesthesia on the Quality of Recovery After Gynecological Laparoscopy: A Prospective Randomized Controlled Trial

Purpose

Opioid-free anesthesia (OFA) is an emerging technique that eliminates intraoperative use of opioids and is associated with lower postoperative opioid consumption and reduced adverse postoperative events. The present study investigated the effect of OFA on the quality of recovery in patients undergoing gynecological laparoscopy.

Patients and Methods

Seventy-five adult patients undergoing elective gynecological laparoscopy were randomly assigned to the OFA group with dexmedetomidine and lidocaine or the remifentanil-based anesthesia (RA) group with remifentanil. Patients, surgeons, and medical staff members providing postoperative care and assessing outcomes were blinded to group allocation. The anesthesiologist performing general anesthesia could not be blinded due to the different drug administration protocols by groups. The primary outcome was the quality of recovery measured using the Quality of Recovery-40 (QoR-40) questionnaire. Secondary outcomes were postoperative pain score, intraoperative and postoperative adverse events, and stress hormones levels.

Results

The patients in both groups had comparable baseline characteristics. The QoR-40 score on postoperative day 1 was significantly higher in the OFA group than in the RA group (155.9 ± 21.2 in the RA group vs 166.9 ± 17.8 in the OFA group; mean difference: −11.0, 95% confidence interval: −20.0, −2.0; p = 0.018). The visual analog scale score at 30 min after surgery was significantly lower in the OFA group than in the RA group (6.3 ± 2.3 in the RA group vs 4.1 ± 2.1 in the OFA group; p < 0.001). The incidences of nausea and shivering in the post-anesthetic care unit were also significantly lower in the OFA group (p = 0.014 and 0.025; respectively). Epinephrine levels were significantly lower in the OFA group (p = 0.002).

Conclusion

OFA significantly improved the quality of recovery in patients undergoing gynecological laparoscopy.

Opioid-free anesthesia compared to opioid anesthesia for laparoscopic radical colectomy with pain threshold index monitoring: a randomized controlled study

BACKGROUND

Few studies have investigated the depth of intraoperative analgesia with non-opioid anesthesia. This study evaluated whether opioid-free anesthesia can provide an effective analgesia-antinociception balance monitored by the / pain threshold index in laparoscopic radical colectomy.

METHODS

We enrolled 102 patients undergoing laparoscopic radical colectomy with general anesthesia. Participants were randomly allocated into two groups to receive opioid-free anesthesia (group OFA) with dexmedetomidine (loading dose with 0.6 μg·kg^-1 for 10 min and then 0.5 μg·kg^-1·h^-1 continuous infusion) and sevoflurane plus bilateral paravertebral blockade (0.2 μg·kg^-1 dexmedetomidine and 0.5% ropivacaine 15 ml per side) or opioid-based anesthesia (group OA) with remifentanil, sevoflurane, and bilateral paravertebral blockade (0.5% ropivacaine 15 ml per side). The primary outcome variable was pain intensity during the operation, as assessed by the pain threshold index with the multifunction combination monitor HXD- I. Results were analyzed using repeated measures analysis of variance and Student's t-test. The secondary outcomes were wavelet index, lactic levels, and blood glucose concentration during the operation. The visual analog scale (VAS), rescue analgesic consumption, and side-effects of opioids after surgery were further assessed.

RESULTS

One hundred and one patients were included in the analysis. Analysis revealed that the intraoperative pain threshold index readings were not significantly different between the groups from incision to the end of the operation (P = 0.06). Furthermore, similar changes in the brain wavelet index readings were observed in the OFA and OA groups. There was no statistical difference in VAS scores between the groups (P > 0.05); however, non-opioid anesthesia did reduce the rescue analgesic consumption after operation (P < 0.05). In the OFA group, the blood glucose levels increased by 20% compared to baseline and were significantly higher than those in the OA group (P < 0.001). The incidences of postoperative nausea and vomiting, urine retention, intestinal paralysis and pruritus were not significantly different from those in the OA group (P > 0.05).

CONCLUSIONS

This study suggests that compared to the opioid anesthesia regimen, our opioid-free anesthesia regimen achieved an equally effective intraoperative pain threshold index in laparoscopic radical colectomy. The incidence of opioid-related adverse reactions was not different between regimens, and intraoperative blood glucose levels were higher with opioid-free anesthesia.

TRIAL REGISTRATION

ChiCTR1900021223, 02/02/2019, Title: " Opioid-free anesthesia in laparoscopic surgery: a randomized controlled trial ". Website: hppts:// www.chictr.ogr.cn.

New Insights Into the Pharmacological Management of Postoperative Pain: A Narrative Review

Postoperative pain is prevalent and often undertreated. There is a risk that untreated or suboptimally treated postoperative pain may transition into chronic postoperative pain, which can be challenging to treat. Clinical guidelines recommend the use of multimodal analgesia, including non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, and, in some cases, opioids. NSAIDs are a broad class of drugs with different attributes such as cyclo-oxygenase (COX)-1 or COX-2 selectivity, onset of action, and analgesic potency. NSAIDs are associated with gastrointestinal and cardiovascular side effects and should be administered at the lowest effective dose for the shortest effective duration but can be effective in postoperative pain. The role of opioids in postoperative analgesia is long-standing but has recently come under scrutiny. Opioids are often used in multimodal analgesic combinations in such a way as to minimize the total consumption of opioids without sacrificing analgesic benefit. Special clinical considerations are required for surgical patients already on opioid regimens or with opioid use disorder. A particularly useful fixed-dose combination product for postoperative analgesia is dexketoprofen-tramadol, which confers safe and effective postoperative pain control and reduces the risk of persistent postoperative pain.

Research advances in the clinical application of esketamine

Esketamine is dextrorotatory ketamine, which is an enantiomer of ketamine. Compared with ketamine, it has the advantages of a fast metabolism, fewer side effects, and strong pharmacological effects, so it is more suitable for clinical use. Esketamine has a powerful analgesic effect and has little effect on breathing. It has a wide range of applications in the fields of pediatric anesthesia, conscious sedation anesthesia, and emergency analgesia. In addition, it is also used for pain that is difficult to relieve with conventional drugs and to prevent postoperative pain. Various routes of administration are also suitable for patients who need short-term analgesia and sedation. As a drug, esketamine inevitably brings some side effects when it is used clinically. In this article, by introducing the mechanism of action and pharmacological characteristics of esketamine, its clinical application is reviewed, and it provides a reference for the more reasonable and safe clinical application of esketamine.

Opioid-free anesthesia in oncologic surgery: the rules of the game

BACKGROUND

Opioids are frequently used in the postoperative period due to their analgesic properties. While these drugs reduce nociceptive somatic, visceral, and neuropathic pain, they may also lead to undesirable effects such as respiratory depression, urinary retention, nausea and vomiting, constipation, itching, opioid-induced hyperalgesia, tolerance, addiction, and immune system disorders. Anesthesiologists are in the critical position of finding balance between using opioids when they are necessary and implementing opioid-sparing strategies to avoid the known harmful effects. This article aims to give an overview of opioid-free anesthesia.

MAIN BODY

This paper presents an overview of opioid-free anesthesia and opioid-sparing anesthetic techniques. Pharmacological and non-pharmacological strategies are discussed, highlighting the possible advantages and drawbacks of each approach.

CONCLUSIONS

Choosing the best anesthetic protocol for a patient undergoing cancer surgery is not an easy task and the available literature provides no definitive answers. In our opinion, opioid-sparing strategies should always be implemented in routine practice and opioid-free anesthesia should be considered whenever possible. Non-pharmacological strategies such as patient education, while generally underrepresented in scientific literature, may warrant consideration in clinical practice.

Anesthesia and Cancer, Friend or Foe? A Narrative Review

Cancer remains the leading cause of death worldwide with close to 10 million deaths reported annually. Due to growth of the advanced age cohort in our population, it is predicted that the number of new cancer cases diagnosed between now until 2035 is to reach potentially 24 million individuals, a staggering increase in a relatively short time period. For many solid tumors, surgical resection along with chemotherapy is the best available approach to a potential cure which leads to almost 80% of cancer patients undergoing at least one surgical procedure during the course of their disease. During surgical intervention, the exposure to general anesthesia can be lengthy, complex and often involves various modalities resulting in an important question as to the role, if any, anesthesia may play in primary recurrence or metastatic conversion. Many components of the stress and inflammatory responses exhibited in the perioperative period can contribute to cancer growth and invasion. The agents used to induce and maintain general anesthesia have variable interactions with the immune and neuroendocrine systems and can influence the stress response during surgery. Thus, debating the best type of anesthesia that would help to attenuate sympathetic and/or pro-inflammatory responses while modulating cytokine release and transcription factors/oncogenes remains at the forefront. This may affect inducible cancer cell survival and migratory abilities not only intra-operatively, but also during the immediate post-operative phase of recovery. The ultimate question becomes how and whether the choice of anesthesia may influence the outcomes of cancer surgery with two major approaches being considered, i.e., regional and general anesthesia as well as the various hypnotics, analgesics and sympatholytics commonly used. In this review, we will address the latest information as to the role that anesthesia may play during cancer surgery with specific focus on primary recurrence and metastasis.

Opioid-free anesthesia compared to opioid anesthesia for lung cancer patients undergoing video-assisted thoracoscopic surgery: A randomized controlled study

BACKGROUND

Reducing intra-operative opioid consumption benefits patients by decreasing postoperative opioid-related adverse events. We assessed whether opioid-free anesthesia would provide effective analgesia-antinociception monitored by analgesia index in video-assisted thoracoscopic surgery.

METHODS

Patients (ASA Ⅰ-Ⅱ, 18-65 years old, BMI <30 kg m-2) scheduled to undergo video-assisted thoracoscopic surgery under general anesthesia were randomly allocated into two groups to receive opioid-free anesthesia (group OFA) with dexmedetomidine, sevoflurane plus thoracic paravertebral blockade or opioid-based anesthesia (group OA) with remifentanil, sevoflurane, and thoracic paravertebral blockade. The primary outcome variable was pain intensity during the operation, assessed by the depth of analgesia using the pain threshold index with the multifunction combination monitor HXD‑I. Secondary outcomes included depth of sedation monitoring by wavelet index and blood glucose concentration achieved from blood gas.

RESULTS

One hundred patients were randomized; 3 patients were excluded due to discontinued intervention and 97 included in the final analysis. Intraoperative pain threshold index readings were not significantly different between group OFA and group OA from arriving operation room to extubation (P = 0.86), while the brain wavelet index readings in group OFA were notably lower than those in group OA from before general anesthesia induction to recovery of double lungs ventilation (P <0.001). After beginning of operation, the blood glucose levels in group OFA increased compared with baseline blood glucose values (P < 0.001). The recovery time and extubation time in group OFA were significantly longer than those in group OA (P <0.007).

CONCLUSIONS

This study suggested that our OFA regimen achieved equally effective intraoperative pain threshold index compared to OA in video-assisted thoracoscopic surgery. Depth of sedation was significantly deeper and blood glucose levels were higher with OFA. Study's limitations and strict inclusion criteria may limit the external validity of the study, suggesting the need of further randomized trials on the topic. Trial registration: ChiCTR1800019479, Title: "Opioid-free anesthesia in video-assisted thoracoscopic surgery lobectomy".

A Global Survey on Opioid Stewardship Practices in Hospitals: A Cross-Sectional Pilot Study

Objective: The objectives of this study are to describe opioid stewardship practices in hospitals being implemented globally, in addition to investigating the attitudes and perceptions of health professionals regarding opioid stewardship in the hospital setting. Methods: A survey was developed by the research team to ask about participants’ attitudes and perceptions regarding opioid stewardship practices. The survey was piloted for performance by five independent third-party healthcare professionals prior to being made available online, being hosted using Research Electronic Data Capture software, with invitations distributed by the International Pharmaceutical Federation (FIP). Descriptive analyses were used to describe the features of the study, and responses obtained from the survey were further categorised into subgroups separating answers relating to attitudes and perceptions, and policies and regulations. Results: Overall, there were 50 respondents from 18 countries, representing an 8% response rate from the FIP hospital pharmacy section mailing list. In total, 33/50 (66%) participants agreed opioids are overused nationally, with 22/49 (45%) agreeing they are overused at their workplace. Furthermore, 32/50 (64%) agreed the opioid crisis is a significant problem nationally, and 44/50 (88%) agreed opioid stewardship would reduce problems associated with the opioid crisis. Policies to educate providers about safe opioid prescribing were uncommon, not exhibited in 26/46 (57%) of hospitals, with all EMR and SE Asia hospitals not displaying this policy. Policy for investigation of narcotic discrepancies was present in 34/46 (74%) of hospitals, and there was a policy for reporting discrepancies at 33/46 (72%) hospitals. Conclusion: In conclusion, healthcare professionals in the American region are more likely to perceive the opioid crisis as a problem, as opposed to those from the European region. Regardless of the presence or absence of a crisis, the implementation of further opioid education and stewardship practices are necessary globally and will contribute to safer prescribing and utilisation practices in hospitals.

Effects of the ultra-short-acting beta-blocker Esmolol infusion on cardiovascular parameters and quality of postoperative recovery in patients scheduled for elective plastic surgery

Background/Aim: Esmolol is an ultra-short-acting, easily titratable b-adrenergic receptor antagonist used for urgent treatment of hypertension and tachycardia in non-surgical and surgical settings. Aim of this clinical study was to investigate its cardiovascular effects and quality of the emergence from anaesthesia in patients scheduled for elective plastic surgery under general balanced anaesthesia. Methods: A total of 30 ASA I/II patients were randomised in two groups of similar demographic characteristics and baseline values of cardiovascular parameters. Esmolol group received esmolol dissolved in glucose 5 % as an intravenous infusion, 0.3 mg/kg/min during the first 5 min and at a rate of 0.1 mg/kg/ min thereafter. Control patients received the solvent only, at the same rate and volume. General balanced anaesthesia was induced with thiopentone sodium and fentanyl and maintained with nitrous oxide and oxygen. Neuromuscular relaxation was assured with pancuronium bromide and was antagonised at the end of operation with atropine and neostigmine. Systolic and diastolic blood pressure and heart rate were registered at all critical phases: (1) immediately prior to the induction (baseline value), (2) induction to anaesthesia, (3) tracheal intubation, (4) first skin incision, (5) surgical manipulation with organs, (6) suture of the surgical wound and (7) tracheal extubation. Drug consumption and quality of postoperative recovery were monitored. Results: In most of the critical phases of anaesthesia and operation, patients from the Esmolol group had significantly lower values of cardiovascular parameters than the patients from the Control group. Esmolol-treated patients needed less fentanyl, droperidol and pancuronium and had faster and smoother emergence from anaesthesia than the control patients. Conclusion: Esmolol improved haemodynamics and post-anaesthesia recovery in patients undergoing elective plastic surgery under general balanced anaesthesia.