Opioid-free anesthesia versus opioid-inclusive anesthesia for breast cancer surgery: a retrospective study

Dexmedetomidine as an Adjuvant to Nerve Block for Cancer Surgery: A Systematic Review and Meta-Analysis

Background/Objectives: Our understanding of dexmedetomidine, as an adjuvant to nerve blocks in cancer surgery, is characterized by a current lack of compelling evidence, and it remains unknown whether the potential benefits of use outweigh the risks. The aim of the study was to evaluate the benefit and safety profiles of dexmedetomidine as an adjuvant to nerve blocks in cancer surgery. Methods: Systematic searches were conducted in MEDLINE, ScienceDirect, Cochrane Library, Springer, medRxiv, and Scopus up to 17 May 2024. Risk ratios (RR) for binary outcomes and standardized mean differences (SMDs) for continuous outcomes were quantified. Results: Twenty studies were identified. In breast cancer surgery, the use of dexmedetomidine reduced 24 h total morphine consumption (SMD = -1.99 [95% CI -3.01 to -0.98], p = 0.0001, I2 = 91%, random effects) and prolonged the requirement for morphine rescue analgesia (SMD = 2.98 [95% CI 0.01 to 5.95], p = 0.05, I2 = 98%, random effects). In abdominal cancer surgery, the dexmedetomidine group had lower total sufentanil consumption (SMD = -1.34 [95% CI -2.29 to -0.40], p = 0.005, I2 = 84%, random effects). Dexmedetomidine reduced the VAS score and decreased postoperative nausea and vomiting (PONV). No studies using dexmedetomidine reported serious adverse events. Conclusions: Using dexmedetomidine as an adjuvant to nerve blocks in cancer surgery could lower the VAS pain score and prolong the regional anesthesia duration, which would lead to a decrease in total opioid consumption and possibly contribute to fewer PONV events. Furthermore, the reports of no serious adverse events indicate its good safety profile.

Ultrasound-Guided Regional Anesthesia Using a Mixture of Dexamethasone, Dexmedetomidine, and 0.2% Levobupivacaine for Bilateral Breast Cancer Surgery Under a Spontaneous Breathing Opioid-Free Anesthesia: A Case Report

Breast cancer is unfortunately the most common cancer in women, although survival rates have greatly increased in recent years. Breast surgery can be very aggressive and therefore highly painful, leading to high rates of acute postsurgical pain and chronic pain. In addition to general anesthesia (GA), ultrasound-guided regional anesthesia (RA) is sometimes performed to help reduce acute postoperative pain and consumption of opioids. Although effective, the main limitation of fascial plane blocks is that they require high volumes of local anesthetics, carrying the risk of local anesthetic systemic toxicity. In this article, we present the case of a 41-year-old woman, who refused GA and was successfully operated on for bilateral breast cancer, under a spontaneous breathing opioid-free sedation and ultrasound-guided RA, based on only 0.2% levobupivacaine with the addition of dexamethasone and dexmedetomidine as adjuvants. Despite this, postoperative analgesia lasted for more than 48 hours, and the patient did not require additional analgesia or opioids.

Effect of opioid-free anesthesia on the incidence of postoperative nausea and vomiting: A meta-analysis of randomized controlled studies

BACKGROUND

Research on opioid-free anesthesia has increased in recent years; however, it has never been determined whether it is more beneficial than opioid anesthesia. This meta-analysis was primarily used to assess the effect of opioid-free anesthesia compared with opioid anesthesia on the incidence of postoperative nausea and vomiting.

METHODS

We searched the electronic databases of PubMed, the Cochrane Library, Web of Science and Embase from 2014 to 2022 to identify relevant articles and extract relevant data. The incidence of postoperative nausea and vomiting, time to extubation, pain score at 24 hours postoperatively, and time to first postoperative rescue analgesia were compared between patients receiving opioid-free anesthesia and those receiving standard opioid anesthesia. Differences in the incidence of postoperative nausea and vomiting were evaluated using risk ratios (95% confidence interval [CI]). The significance of the differences was assessed using mean differences and 95% CI. The heterogeneity of the subject trials was evaluated using the I2 test. Statistical analysis was performed using the RevMan 5.4 software.

RESULTS

Fourteen randomized controlled trials, including 1354 participants, were evaluated in the meta-analysis. As seen in the forest plot, the OFA group had a lower risk of postoperative nausea and vomiting than the control group (risk ratios = 0.41, 95% CI: 0.33-0.51, P < .00001; n = 1354), and the meta-analysis also found that the OFA group had lower postoperative analgesia scores at 24 hours (P < .000001), but time to extubation (P = .14) and first postoperative resuscitation analgesia time (P < .54) were not significantly different.

CONCLUSIONS

Opioid-free anesthesia reduces the incidence of postoperative nausea and vomiting while providing adequate analgesia without interfering with postoperative awakening.

Role of Magnesium in the Intensive Care Unit and Immunomodulation: A Literature Review

Both the role and the importance of magnesium in clinical practice have grown considerably in recent years. Emerging evidence suggests an association between loss of magnesium homeostasis and increased mortality in the critical care setting. The underlying mechanism is still unclear, but an increasing number of in vivo and in vitro studies on magnesium's immunomodulating capabilities may shed some light on the matter. This review aims to discuss the evidence behind magnesium homeostasis in critically ill patients, and its link with intensive care unit mortality via a likely magnesium-induced dysregulation of the immune response. The underlying pathogenetic mechanisms, and their implications for clinical outcomes, are discussed. The available evidence strongly supports the crucial role of magnesium in immune system regulation and inflammatory response. The loss of magnesium homeostasis has been associated with an elevated risk of bacterial infections, exacerbated sepsis progression, and detrimental effects on the cardiac, respiratory, neurological, and renal systems, ultimately leading to increased mortality. However, magnesium supplementation has been shown to be beneficial in these conditions, highlighting the importance of maintaining adequate magnesium levels in the intensive care setting.

The efficacy and safety of an adapted opioid-free anesthesia regimen versus conventional general anesthesia in gynecological surgery for low-resource settings: a randomized pilot study

Introduction

There is scarce data on the safety and efficacy of opioid-free anesthesia (OFA), in resource-limited settings due to the non-availability of dexmedetomidine, the reference OFA agent. We aimed to demonstrate the feasibility, efficacy and safety of a practical OFA protocol not containing dexmedetomidine, adapted for low-resource environments in very painful surgeries like gynecological surgery.

Methods

We conducted a randomized pilot study on ASA I and II women undergoing elective gynecological surgery at a tertiary care hospital in Cameroon. Patients were matched in a ratio of 1:1 into an OFA and a conventional general anesthesia (CGA) group. The OFA protocol entailed the intravenous (IV) magnesium sulfate, lidocaine, ketamine, dexamethasone, propofol, and rocuronium, followed by isoflurane and a continuous infusion of a calibrated mixture of magnesium sulfate, ketamine and clonidine. The CGA protocol was IV dexamethasone, diazepam, fentanyl, propofol, and rocuronium, followed by isoflurane and reinjections of fentanyl propofol and a continuous infusion of normal saline as placebo. The primary endpoints were the success rate of OFA, isoflurane consumption and intraoperative anesthetic complications. The secondary endpoints were postoperative pain intensity, postoperative complications, patient satisfaction assessed using the QoR-40 questionnaire and the financial cost of anesthesia.

Results

We enrolled a total of 36 women undergoing gynecological surgery; 18 in the OFA group and 18 in the CGA group. The success rate of OFA was 100% with significant lesser consumption of isoflurane in the OFA group, no significant intraoperative complication and better intraoperative hemodynamic stability in the OFA group. Postoperatively, compared to the CGA group, the OFA group had statistically significantly less pain during the first 24 h, no morphine consumption for pain relief, had less hypoxemia during the first six hours, less paralytic ileus, less nausea and vomiting, no pruritus and better satisfaction. The mean financial cost of this adapted OFA protocol was statistically significant lesser than that of CGA.

Conclusion

This OFA regimen without dexmedetomidine for a low-resource setting has a promising success rate with few perioperative complications including mild intraoperative hemodynamic changes, decrease postoperative complications, pain, and opioid consumption in patients undergoing elective gynecology surgery.

Trial registration

This study was registered at clinicaltrials.gov on 03/02/2021 under the registration number NCT04737473.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01856-6.