Impact of opioid-free anaesthesia on postoperative nausea, vomiting and pain after gynaecological laparoscopy - A randomised controlled trial

Opioid-free anesthesia with esketamine-dexmedetomidine versus opioid-based anesthesia with propofol-remifentanil in shoulder arthroscopy: a randomized controlled trial

BACKGROUND

OFA (Opioid-free anesthesia) has the potential to reduce the occurrence of opioid-related adverse events and enhance postoperative recovery. Our research aimed to investigate whether OFA, combining esketamine and dexmedetomidine, could serve as an alternative protocol to traditional OBA (opioid-based anesthesia) in shoulder arthroscopy, particularly in terms of reducing PONV (postoperative nausea and vomiting).

METHODS

A total of 60 patients treated with shoulder arthroscopy from September 2021 to September 2022 were recruited. Patients were randomly assigned to the OBA group (n = 30) and OFA group (n = 30), receiving propofol-remifentanil TIVA (total intravenous anesthesia) and esketamine-dexmedetomidine intravenous anesthesia, respectively. Both groups received ultrasound-guided ISBPB(interscalene brachial plexus block)for postoperative analgesia.

RESULTS

The incidence of PONV on the first postoperative day in the ward (13.3% vs. 40%, P < 0.05) was significantly lower in the OFA group than in the OBA group. Moreover, the severity of PONV was less severe in the OFA group than in the OBA group in PACU (post-anesthesia care unit) (0 [0, 0] vs. 0 [0, 3], P<0.05 ) and in the ward 24 h postoperatively ( 0 [0, 0] vs. 0 [0, 2.25], P<0.05). Additionally, the OFA group experienced a significantly shorter length of stay in the PACU compared to the OBA group (39.4 ± 6.76 min vs. 48.7 ± 7.90 min, P < 0.001).

CONCLUSIONS

Compared to the OBA with propofol-remifentanil, the OFA with esketamine- dexmedetomidine proved to be feasible for shoulder arthroscopy, resulting in a reduced incidence of PONV and a shorter duration of stay in the PACU.

TRIAL REGISTRATION

The Chinese Clinical Trial Registry (No: ChiCTR2100047355), 12/06/2021.

Opioid-free general anesthesia: considerations, techniques, and limitations

PURPOSE OF REVIEW

To discuss the role of opioids during general anesthesia and examine their advantages and risks in the context of clinical practice. We define opioid-free anesthesia (OFA) as the absolute avoidance of intraoperative opioids.

RECENT FINDINGS

In most minimally invasive and short-duration procedures, nonopioid analgesics, analgesic adjuvants, and local/regional analgesia can significantly spare the amount of intraoperative opioid needed. OFA should be considered in the context of tailoring to a specific patient and procedure, not as a universal approach. Strategies considered for OFA involve several adjuncts with low therapeutic range, requiring continuous infusions and resources, with potential for delayed recovery or other side effects, including increased short-term and long-term pain. No evidence indicates that OFA leads to decreased long-term opioid-related harms.

SUMMARY

Complete avoidance of intraoperative opioids remains questionable, as it does not necessarily ensure avoidance of postoperative opioids. Multimodal analgesia including local/regional anesthesia may allow OFA for selected, minimally invasive surgeries, but further research is necessary in surgeries with high postoperative opioid requirements. Until there is definitive evidence regarding procedure and patient-specific combinations as well as the dose and duration of administration of adjunct agents, it is imperative to practice opioid-sparing approach in the intraoperative period.

Comparison of opioid-free and opioid-inclusive propofol anaesthesia for thyroid and parathyroid surgery: a randomised controlled trial

BACKGROUND

Postoperative nausea and vomiting occur frequently following thyroid and parathyroid surgery and are associated with worse patient outcomes. We hypothesised that opioid-free propofol anaesthesia would reduce the incidence of postoperative nausea and vomiting compared with opioid-inclusive propofol anaesthesia in patients undergoing these procedures.

METHODS

We conducted a randomised, double-blinded controlled trial in adult patients scheduled to undergo thyroid and parathyroid surgery at two medical centres in mainland China. Patients were allocated randomly (1:1, stratified by sex and trial site) to an opioid-free anaesthesia group (esketamine, lidocaine, dexmedetomidine and propofol) or an opioid-inclusive group (sufentanil and propofol). Propofol infusions were titrated to bispectral index 45-55. Patients received prophylaxis for nausea and vomiting using dexamethasone and ondansetron and multimodal analgesia with paracetamol and flurbiprofen axetil. The primary outcome was the incidence of postoperative nausea and vomiting in the first 48 h after surgery.

RESULTS

We assessed 557 patients for eligibility and 394 completed this trial. The incidence of postoperative nausea and vomiting in the first postoperative 48 h was lower in the opioid-free anaesthesia group (10/197, 5%) compared with opioid-inclusive group (47/197, 24%) (OR (95%CI) 0.17 (0.08-0.35), p < 0.001), yielding a number needed to treat of 5.3. Additionally, opioid-free propofol anaesthesia was associated with a reduced need for rescue anti-emetics, lower rates of hypotension and desaturation after tracheal extubation, and higher patient satisfaction. Time to tracheal extubation was prolonged slightly in the opioid-free group. The two groups had similar postoperative pain scores and 30-day outcomes.

DISCUSSION

Opioid-free propofol anaesthesia reduced postoperative nausea and vomiting in patients undergoing thyroid and parathyroid surgery. An opioid-free anaesthetic regimen can optimise anaesthetic care during thyroid and parathyroid surgery.

Mapping Theme Trends and Research Frontiers in Dexmedetomidine Over Past Decade: A Bibliometric Analysis

Background

Dexmedetomidine, an α2-adrenergic receptor (α2-AR) agonist, is extensively used in clinical and animal studies owing to its sedative, analgesic, and anxiolytic effects. The diverse range of research domains associated with dexmedetomidine poses challenges in defining pivotal research directions. Therefore, this study aimed to conduct a qualitative and quantitative bibliometric study in the field of dexmedetomidine over the past decade to establish current research trends and emerging frontiers.

Methods

Relevant publications in the field of dexmedetomidine between 2014 and 2023 were extracted from the Web of Science Core Collection database. The bibliometric analysis, incorporating statistical and visual analyses, was conducted using CiteSpace (6.1.R6) and R (4.3.1).

Results

The present study encompassed a total of 5,482 publications, exhibiting a consistent upward trend over the past decade. The United States and its institutions had the highest centrality. Ji, Fuhai, and Ebert, Thomas J. were identified as the most productive author and the most cited author, respectively. As anticipated, the most cited journal was Anesthesiology. Moreover, cluster analysis of cited references and co-occurrence of keywords revealed that recent studies were primarily focused on sedation, delirium, and opioid-free anesthesia. Finally, a timeline view of keywords clusters and keywords burst demonstrated that primary research frontiers were stress response, neuroinflammation, delirium, opioid-free anesthesia, peripheral nerve block, and complications.

Conclusion

Current research trends and directions are focused on sedation, delirium, and opioid-free anesthesia, as evidenced by our results. The frontier of future research is anticipated to encompass basic investigations into dexmedetomidine, including stress response and neuroinflammation, as well as clinical studies focusing on delirium, opioid-free anesthesia, peripheral nerve block, and associated complications.

Esketamine: Less Drowsiness, More Analgesia

Racemic ketamine is a 1:1 mixture of 2 enantiomers that turn light in opposite direction: Dextrorotatory esketamine is approximately 4 times more affine for the N-methyl-D-aspartate (NMDA) receptor than levorotatory arketamine, which may explain why esketamine is about twice as potent as an analgesic and anesthetic as the racemate. Esketamine has attracted renewed interest in view of the opioid crisis, racemic ketamine's abuse, and esketamine's approval for expanded use. We evaluated the anesthesia literature concerning mental, cardiovascular, cerebral, and antinociceptive effects of esketamine published in English between 1980 and 2022. The review shows that esketamine and racemic ketamine are not "the same" at clinically equivalent analgesic and anesthetic dose: Psychomimetic effects seem to be essentially related to NMDA receptor blockade and esketamine is not devoid of unwanted mental impact. However, it probably involves less cholinergic inhibition. Cognitive disturbances during arousal, awakening, and recovery from the drug are less, and less pronounced with esketamine. The drug allows for an approximately 50% dose reduction in anesthesia and analgesia which goes along with a higher clearance and shorter recovery time as compared to racemic ketamine. In comparison of esketamine with placebo, esketamine shows cardiocirculatory stabilizing and neuroprotective effects which can be seen in anesthesia induction, cardiac surgery, and analgesia and sedation in brain injury. Evidence of esketamine's antinociceptive efficacy is inconsistent, although a recent meta-analysis reports improved pain relief after surgery in a study with short observation time. To better define esketamine's place, direct head-to-head comparison with the racemate at equi-analgesic/anesthetic dose is warranted.

Balanced opioid-free anesthesia with lidocaine and esketamine versus balanced anesthesia with sufentanil for gynecological endoscopic surgery: a randomized controlled trial

In this randomized controlled trial, 74 patients scheduled for gynecological laparoscopic surgery (American Society of Anesthesiologists grade I/II) were enrolled and randomly divided into two study groups: (i) Group C (control), received sufentanil (0.3 μg/kg) and saline, followed by sufentanil (0.1 μg/kg∙h) and saline; and (ii) Group F (OFA), received esketamine (0.15 mg/kg) and lidocaine (2 mg/kg), followed by esketamine (0.1 mg/kg∙h) and lidocaine (1.5 mg/kg∙h). The primary outcome was the 48-h time-weighted average (TWA) of postoperative pain scores. Secondary outcomes included time to extubation, adverse effects, and postoperative sedation score, pain scores at different time points, analgesic consumption at 48 h, and gastrointestinal functional recovery. The 48-h TWAs of pain scores were 1.32 (0.78) (95% CI 1.06-1.58) and 1.09 (0.70) (95% CI 0.87-1.33) for Groups F and C, respectively. The estimated difference between Groups F and C was - 0.23 (95% CI - 0.58 - 0.12; P = 0.195). No differences were found in any of the secondary outcomes and no severe adverse effects were observed in either group. Balanced OFA with lidocaine and esketamine achieved similar effects to balanced anesthesia with sufentanil in patients undergoing elective gynecological laparoscopic surgery, without severe adverse effects.Clinical Trial Registration: ChiCTR2300067951, www.chictr.org.cn 01 February, 2023.

Dose-response study of propofol combined with two different doses of esketamine for laryngeal mask airway insertion in women undergoing hysteroscopy

Objective

To prospectively determine the median effective dose (ED50) of propofol for inhibiting a response to laryngeal mask airway (LMA) insertion when combined with different doses of esketamine in female patients.

Methods

A total of 58 female patients (aged 20-60 years, ASAⅠ-Ⅱ) scheduled for elective hysteroscopy were enrolled and randomly divided into 2 groups, one of which was administered 0.2 mg/kg of esketamine (K1 group, n = 28) and the other 0.3 mg/kg of esketamine (K2 group, n = 30). The 2 groups received the corresponding doses of esketamine intravenously, followed by an intravenous injection of propofol (injection time was 30 s). The initial dose of propofol was 2 mg/kg, and the dose ratio of propofol in the adjacent patients was 0.9. If a positive reaction occurred due to LMA insertion, the dose ratio in the next patient was increased by 1 gradient; if not, the dose ratio was decreased by 1 gradient. The ED50, 95 % effective dose (ED95) and 95 % confidence interval (CI) of propofol for inhibiting a response to LMA insertion in the 2 esketamine groups were calculated using probit analysis.

Results

The ED50 of propofol for inhibiting a response to LMA insertion in female patients was 1.95 mg/kg (95 % CI, 1.82-2.08 mg/kg) in the K1 group and 1.60 mg/kg (95 % CI, 1.18-1.83 mg/kg) in the K2 group. The ED95 of propofol for inhibiting a response to LMA insertion in female patients was 2.22 mg/kg (95 % CI, 2.09-2.86 mg/kg) in the K1 group and 2.15 mg/kg (95 % CI, 1.88-3.09 mg/kg) in the K2 group.

Conclusion

Propofol combined with 0.3 mg/kg of esketamine has low ED50 and ED95 effective doses for inhibiting an LMA insertion response in female patients undergoing hysteroscopy and surgery. There were no significant adverse effects, but the additional dose of propofol and airway pressure were significantly higher than those in the group administered 0.2 mg/kg of esketamine. Based on the results, we recommend the combination of propofol with 0.2 mg/kg esketamine for optimal conditions during LMA insertion in women undergoing hysteroscopy.

Effect of S-Ketamine on Postoperative Nausea and Vomiting in Patients Undergoing Video-Assisted Thoracic Surgery: A Randomized Controlled Trial

Purpose

Postoperative nausea and vomiting (PONV) frequently occur in patients after surgery. In this study, the authors investigated whether perioperative S-ketamine infusion could decrease the incidence of PONV in patients undergoing video-assisted thoracoscopic surgery (VATS) lobectomy.

Patients and Methods

This prospective, randomized, double-blinded, controlled study was conducted a total of 420 patients from September 2021 to May 2023 at Xuzhou Central Hospital in China, who underwent elective VATS lobectomy under general anesthesia with tracheal intubation. The patients were randomly assigned to either the S-ketamine group or the control group. The S-ketamine group received a bolus injection of 0.5 mg/kg S-ketamine and an intraoperative continuous infusion of S-ketamine at a rate of 0.25 mg/kg/h. The control group received an equivalent volume of saline. All patients were equipped with patient-controlled intravenous analgesia (PCIA), with a continuous infusion rate of 0.03 mg/kg/h S-ketamine in the S-ketamine group or 0.03 μg/kg/h sufentanil in the control group. The primary outcome was the incidence of PONV. Secondary outcomes included perioperative opioid consumption, hemodynamics, postoperative pain, and adverse events.

Results

The incidence of PONV in the S-ketamine group (9.7%) was significantly lower than in the control group (30.5%). Analysis of perioperative opioid usage revealed that remifentanil usage was 40.0% lower in the S-ketamine group compared to the control group (1414.8 μg vs 2358.2 μg), while sufentanil consumption was 75.2% lower (33.1 μg vs 133.6 μg). The S-ketamine group demonstrated better maintenance of hemodynamic stability. Additionally, the visual analogue scale (VAS) scores on postoperative day 1 (POD-1) and postoperative day 3 (POD-3) were significantly lower in the S-ketamine group. Finally, no statistically significant difference in other postoperative adverse reactions was observed between the two groups.

Conclusion

The results of this trial indicate that perioperative S-ketamine infusion can effectively reduce the incidence of PONV in patients undergoing VATS lobectomy.

[Opioid-free anesthesia : Wrong track or meaningful exit from the era of opioid-based analgesia?]

The limitations and disadvantages of opioids in anesthesia are very well known but the advantages combined with a lack of effective alternatives even now still prevents refraining from using opioids as part of an adequate pain therapy. For decades, pain research has had the declared goal of replacing opioids with new substances which have no serious side effects; however, currently this goal seems to be a long way off. Due to the media coverage of the "opioid crisis" in North America, the use of opioids for pain management is also increasingly being questioned by the patients. Measures to contain this crisis are only slowly taking effect in view of the increasing number of deaths, which is why the triggers are still being sought. The perioperative administration of opioids is not only a possible gateway to addiction and abuse but it can also cause outcome-relevant complications, such as respiratory depression, postoperative nausea and vomiting and an increase in postoperative pain. Therefore, these considerations gave rise to the idea of an opioid-free anesthesia (OFA), i.e., opioids are not administered as part of anesthesia to carry out surgical procedures. Although this idea may make sense at first glance, a rapid introduction of this concept appears to be risky as it entails significant changes for the entire anesthesiological management. Based on relatively robust data from clinical studies, this concept can now be evaluated and discussed not only emotionally but also objectively. This review article presents arguments for or against the complete avoidance of intraoperative or even perioperative opioids. The current conditions in Germany are primarily taken into account, so that the perioperative pain therapy is transferable to the established standards. The results from current clinical studies on the implementation of an opioid-free anesthesia are summarized and discussed.

Efficacy of Intravenous Administration of Esketamine in Preventing and Treating Rebound Pain After Thoracic Paravertebral Nerve Block: A Prospective Randomized, Double-Blind, Placebo-Controlled Trial

Purpose

Investigating the efficacy of intraoperative fractionated intravenous esketamine in the prevention of rebound pain after cessation of thoracic paravertebral nerve blockade.

Methods

One hundred and twenty patients who underwent elective thoracoscopic lobectomy were selected for the study and were randomly divided into two groups, the esketamine group was given 0.5 mg/kg and 0.3 mg/kg of esketamine at the induction of anaesthesia and 30 minutes before the end of the operation, respectively, and the control group was given an equal amount of saline. The incidence of rebound pain (RP) 7 days after surgery and postoperative recovery were compared between the two groups.

Results

The NRS pain scores at 24 and 48 hours postoperatively in the esketamine group were significantly lower than those in the control group (P < 0.05). The incidence of postoperative rebound pain was significantly lower in the esketamine group than in the control group (P < 0.05). The consumption of sufentanil was less in the esketamine group in the postoperative 48 hours (P < 0.05). Postoperative recovery was compared between the two groups and the difference was not statistically significant.

Conclusion

Intravenous esketamine reduces postoperative pain scores, decreases the incidence of rebound pain after cessation of thoracic paravertebral block, and reduces opioid consumption.

Remifentanil is Superior to Propofol for Treating Emergence Agitation in Adults After General Anesthesia

Background

Emergence agitation (EA) is one of the most common complications in clinical general anesthesia during recovery in adults. Remifentanil and propofol can reduce the incidence of EA, but with no randomized controlled trial to evaluate their effectiveness for treating EA. This study aims to compare the effectiveness of remifentanil and propofol for treating EA following general anesthesia.

Patients and methods

Among 152 randomized patients with a mean of 49.5 years, and 99 (65.1%) of them being male, 149 were divided into two groups for subsequent analysis. The remifentanil group (Group R, n = 74) received a 0.5μg kg-1 remifentanil infusion followed by a 0.05μg kg-1 min-1 infusion until 15 minutes, after the onset of agitation. The propofol group (Group P, n = 75) received a 1mg kg-1 propofol infusion once agitation occurred. Emergence agitation was assessed using the Riker Sedation Agitation Score, with a score of ≥5 defining emergence agitation. During the post-anesthesia care unit (PACU), the recurrence of emergence agitation, time to extubation, and discharge from PACU were evaluated.

Results

The incidence of reoccurring emergence agitation was lower in Group R (29.7%) compared with Group P (49.3%), with an odds ratio of 0.44 (95% CI 0.22-0.85; P=0.014). The time to extubation was shorter in Group R (mean 12min, range 8-15 min) compared with Group P (mean 17min, range 13-21 min) (P<0.001), as was the time discharge from the PACU (mean 30.5 min, range 25-40 min) vs Group P (mean 37.5 min, range 31-50 min) (P=0.001).

Conclusion

Treatment of emergence agitation in adults with remifentanil infusion is more effective than propofol, with a shorter time to extubation and discharge from PACU.

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).

Effect of opioid-free anesthesia on postoperative nausea and vomiting after gynecological surgery: a systematic review and meta-analysis

Background: Postoperative nausea and vomiting (PONV) is a common complication, that can reduce patient satisfaction and may lead to serious consequences, such as wound dehiscence. Many strategies have been proposed to prevent PONV; however, it remains common, especially in high-risk surgeries such as gynecological surgery. In recent years, opioid-free anesthesia has been widely studied because it minimizes adverse reactions of opioids, such as nausea, vomiting, and itching; however, conclusions have been inconsistent. Therefore, we conducted this meta-analysis to investigate the effects of opioid-free anesthesia on PONV in patients undergoing gynecological surgery. Methods: A systematic search of the PubMed, Web of Science, Cochrane Library, and Embase databases, from inception to 28 August 2023, was performed. Keywords and other free terms were used with Boolean operators (OR and, AND) to combine searches. This review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Results: Six studies involving 514 patients who underwent gynecological surgery were included. The forest plot revealed that the incidence of PONV (risk ratio = 0.52; p < 0.00001) and consumption of postoperative antiemetics use (risk ratio = 0.64; p = 0.03) were significantly lower in the opioid-free anesthesia group. In addition, opioid-free anesthesia improved the quality of recovery (mean difference = 4.69; p < 0.0001). However, there were no significant differences in postoperative pain scores (mean difference = 0.05; p = 0.85), analgesic use (risk ratio = 1.09; p = 0.65), and the time of extubation (mean difference = -0.89; p = 0.09) between the opioid-free anesthesia and control groups. Conclusion: OFA reduces PONV and the use of antiemetic drugs. In addition, it improves the quality of postoperative recovery. However, OFA can not reduce the postoperative pain scores, analgesic use and the time of extubation. Due to the strength of the evidence, we cannot support OFA as an ideal anesthesia method in gynecological surgery, and the implementation of anesthesia strategies should be case-by-case. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=462044], identifier [CRD42023462044].

Effect of ultrasound-guided femoral nerve block with dexmedetomidine and ropivacaine on postoperative analgesia in patients undergoing total knee arthroplasty: a randomized controlled trial

Background

Dexmedetomidine, a potent and highly selective α2-adrenoreceptor agonist, has become a popular adjuvant to local anesthetics. This study was designed to investigate the effect of dexmedetomidine with ropivacaine for femoral nerve block on postoperative analgesia after total knee arthroplasty.

Methods

Forty-six patients after total knee arthroplasty received ultrasound-guided femoral nerve block with either 0.3% ropivacaine alone (group R) or 0.3% ropivacaine with 0.5 μg/kg dexmedetomidine (group RD). Total 24-h sufentanil consumption, visual analogue scale (VAS) pain scores, frequency of patient-controlled analgesia (PCA) pressed, Ramsay sedation score, the incidence of bradycardia and hypotension, and incidence of postoperative nausea and vomiting (PONV) were recorded.

Results

Compared to group R, the total 24-h sufentanil consumption was significantly reduced (110.76 ± 11.56 vs. 99.09 ± 13.31; P<0.05), the VAS scores were lower at 10 and 12 h postoperatively [3(2-3) vs. 2(1-2) and 3(2-3) vs. 2(1-3), respectively; P<0.05], the frequency of PCA pressed was lower at 8-12 and 12-16-h time intervals [(5(3-6) vs. 2(1-3) and 4(3-4) vs. 2(1-3), respectively; P<0.05]. However, there were no differences in Ramsay's sedation score and the incidence of PONV. Also, no patient experienced bradycardia and hypotension.

Conclusions

0.5 μg/kg dexmedetomidine with 0.3% ropivacaine for femoral nerve block significantly decreased the total 24-h sufentanil consumption, prolonged and enhanced the analgesic efficacy of ropivacaine, without clinically relevant cardiovascular depression or over-sedation in patients undergoing total knee arthroplasty.

The efficacy and safety of opioid-free anesthesia combined with ultrasound-guided intermediate cervical plexus block vs. opioid-based anesthesia in thyroid surgery-a randomized controlled trial

PURPOSE

In the context of the current comfort medicine and enhanced recovery after surgery, there is a demand for a new anesthesia method to reduce adverse reactions and accelerate recovery after surgery. This randomized controlled trial aimed to compare the efficacy and safety between opioid-free anesthesia (OFA) combined with ultrasound-guided intermediate cervical plexus block (ICPB) and opioid-based anesthesia in patients after thyroid surgery.

METHODS

In this study, 75 patients scheduled for thyroid surgery under general anesthesia were randomly allocated into two groups. The primary outcome included the incidence of nausea within 24 h after surgery. The main secondary outcomes included the incidence of vomiting and the visual analog score (VAS) scores within 24 h after surgery as well as the quality of recovery 40 questionnaires (QoR-40) scores 24 h after surgery.

RESULTS

In the OFA group, the incidence of postoperative nausea was 6.1%, compared to 39.4% in the control group (p = 0.001). No patient presented with postoperative vomiting in the OFA group, while 15.2% of patients suffered from postoperative vomiting in the control group (p = 0.063). The VAS scores of patients in the postanesthetic care unit (PACU) and 2 h, 4 h, and 6 h after surgery were lower in the OFA group, and the difference is statistically significant. Besides, the VAS scores of patients at rest (p = 1.000) and during swallowing (p = 1.000) 24 h after surgery were comparable.

CONCLUSION

Compared with opioid-based anesthesia, the OFA combined with the ultrasound-guided ICPB can better improve patients' postoperative recovery, reduce nausea, and decrease pain scores.

TRIAL REGISTRATION

Chinese Clinical Trial Regisrty, ChiCTR2200056344, https://www.chictr.org.cn.

Impact of Opioid-Free Anesthesia on Postoperative Quality of Recovery in Patients After Laparoscopic Cholecystectomy-A Randomized Controlled Trial

Purpose

Opioid analgesics may delay discharge and affect postoperative quality of recovery because of their significant adverse effects, such as hyperalgesia, postoperative nausea and vomiting (PONV), shivering and urine retention. We aimed to compare the quality of postoperative recovery (QoR) between patients undergoing laparoscopic cholecystectomy surgeries with opioid-free anesthesia (OFA) and those with opioid-based anesthesia (OA).

Patients and Methods

80 adult patients undergoing laparoscopic cholecystectomy were randomly allocated to an opioid-free anesthesia group (Group OFA) or an opioid-based anesthesia group (Group OA). The primary outcome was the quality of postoperative recovery using QoR-15 scale on postoperative day 1 (POD 1) and 2 (POD 2). The secondary outcomes included the incidence of opioid-related adverse symptoms, perioperative hemodynamic data, duration of post-anesthesia care unit (PACU) stay and duration of extubation, and the incidences of hypotension and bradycardia.

Results

A statistically significant difference in total QoR-15 was observed between the two groups on POD 1 and POD 2 (91.00 (90.00, 92.00) vs 113.00 (108.25, 115.00), 106.00 (104.00, 112.00) vs 133.00 (130.00, 135.00), P < 0.001). The incidence of opioid-related symptoms was significantly different between the two groups on POD 1 (P < 0.05). There were between-group differences in systolic blood pressure (SBP) and diastolic blood pressure (DBP) at T3 (P < 0.001). There was also a significant difference in the incidence of hypotension between the two groups (P = 0.001). However, there were no significant differences in the duration of PACU stay, duration of extubation and the incidence of bradycardia (P > 0.05). There was no difference in heart rate between the two groups at all observed time points, either (P > 0.05).

Conclusion

We concluded that the quality of recovery of patients receiving OFA was superior to those receiving OA after laparoscopic cholecystectomy.

The ED50 and ED95 of esketamine for preventing early postoperative pain in patients undergoing laparoscopic cholecystectomy: a prospective, double-blinded trial

BACKGROUND

This study aims to estimate the safety, efficacy, and median effective dose (ED50) of esketamine for preventing early postoperative pain in patients undergoing laparoscopic cholecystectomy.

METHODS

54 patients undergoing laparoscopic cholecystectomy were prospectively randomized into two groups (group C and group E). Different doses of esketamine were intravenously administered before the skin incision in Group E. The patients in group C received the same dose of saline at the same time. General population characteristics were recorded. The median effective dose (ED50) and 95% effective dose (ED95) were calculated using Dixon's up-and-down method. Hemodynamic parameters were monitored, and pain intensity was assessed using a visual analog scale. We also recorded the condition of anesthesia recovery period and postoperative adverse reactions.

RESULTS

The ED50 of esketamine for preventing early postoperative pain was 0.301 mg/kg (95%CI: 0.265-0.342 mg/kg), and the ED95 was 0.379 mg/kg (95%CI: 0.340-0.618 mg/kg), calculated by probability unit regression. Heart rate (HR) was significantly lower in the esketamine group compared to the control at the skin incision (p < 0.05). The total VAS score at resting was significantly lower in the esketamine group compared to the control group during the awakening period (p < 0.05). There was no significant difference between the two groups regarding the incidence of adverse reactions (p > 0.05).

CONCLUSIONS

In this study, esketamine can prevent early postoperative pain effectively. The ED50 and ED95 of esketamine for controlling early postoperative pain were 0.301 mg/kg and 0.379 mg/kg, respectively.

TRIAL REGISTRATION

ChiCTR2200066663, 13/12/2022.

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.

Effect of raw electroencephalogram-guided anesthesia administration on postoperative outcomes in elderly patients undergoing abdominal major surgery: a randomized controlled trial

BACKGROUND

EEG monitoring techniques are receiving increasing clinical attention as a common method of reflecting the depth of sedation in the perioperative period. The influence of depth of sedation indices such as the bispectral index (BIS) generated by the processed electroencephalogram (pEEG) machine to guide the management of anesthetic depth of sedation on postoperative outcome remains controversial. This research was designed to decide whether an anesthetic agent exposure determined by raw electroencephalogram (rEEG) can influence anesthetic management and cause different EEG patterns and affect various patient outcomes.

METHODS

A total of 141 participants aged ≥ 60 years undergoing abdominal major surgery were randomized to rEEG-guided anesthesia or routine care group. The rEEG-guided anesthesia group had propofol titrated to keep the rEEG waveform at the C-D sedation depth during surgery, while in the routine care group the anesthetist was masked to the patient's rEEG waveform and guided the anesthetic management only through clinical experience. The primary outcome was the presence of postoperative complications, the secondary outcomes included intraoperative anesthetic management and different EEG patterns.

RESULTS

There were no statistically significant differences in the occurrence of postoperative respiratory, circulatory, neurological and gastrointestinal complications. Further EEG analysis revealed that lower frontal alpha power was significantly associated with a higher incidence of POD, and that rEEG-guidance not only reduced the duration of deeper anesthesia in patients with lower frontal alpha power, but also allowed patients with higher frontal alpha power to receive deeper and more appropriate depths of anesthesia than in the routine care group.

CONCLUSIONS

In elderly patients undergoing major abdominal surgery, rEEG-guided anesthesia did not reduce the incidence of postoperative respiratory, circulatory, neurological and gastrointestinal complications. rEEG-guided anesthesia management reduced the duration of intraoperative BS in patients and the duration of over-deep sedation in patients with lower frontal alpha waves under anesthesia, and there was a strong association between lower frontal alpha power under anesthesia and the development of POD. rEEG-guided anesthesia may improve the prognosis of patients with vulnerable brains by improving the early identification of frail elderly patients and providing them with a more effective individualized anesthetic managements.

Opioid-Free Versus Opioid-Based Anesthesia on Postoperative Pain After Thoracoscopic Surgery: The Use of Intravenous and Epidural Esketamine

BACKGROUND

The effectiveness and safety of opioid-free anesthesia (OFA) regimens in distinct types of surgeries remain controversial. In this study, we investigated whether OFA could reduce the occurrence of chronic postoperative pain in patients receiving video-assisted thoracoscopic surgery (VATS).

METHODS

We conducted a 2-center, randomized, controlled trial from September 2021 to January 2022. A total of 162 lung tumor patients scheduled to undergo VATS were randomly divided into an opioid-based anesthesia (OA) group and an OFA group. The OA group received general anesthesia combined with thoracic epidural block using morphine, while the OFA group received general anesthesia combined with thoracic epidural block using esketamine. Patient-controlled epidural analgesia (PCEA) was used after surgery (ropivacaine and morphine for the OA group versus ropivacaine and esketamine for the OFA group). The primary end point was chronic pain rates at 3 months after VATS, which were analyzed using a logistic regression model. The secondary end points were chronic pain rates at 6 months, acute pain rates at 24 hours and 48 hours postoperatively, postoperative side effects, and perioperative variables.

RESULTS

The final analysis included 159 patients. Acute postoperative pain at 24 hours occurred in 0 of the 79 (0%) patients in the OA group and 10 of the 80 (17.5%) patients in the OFA group (odds ratio, 52.14; 95% confidence interval [CI], 6.47-420.10; P < .001). Acute postoperative pain at 48 hours occurred in 3 of the 79 (3.8%) patients in the OA group and 2 of the 80 (2.5%) patients in the OFA group (odds ratio, 2.07; 95% CI, 0.99-4.32; P = .053). In this study, none of the patients had moderate or severe pain in either group at 3 and 6 months postsurgically. Mild chronic postoperative pain at 3 months occurred in 27 of the 79 (34.2%) patients in the OA group and 14 of the 80 (17.5%) patients in the OFA group (odds ratio, 3.52; 95% CI, 1.49-8.31; P = .004). At 6 months, mild chronic pain still occurred in 23 of the 79 (29.1%) patients in the OA group and 9 of the 80 (11.3%) patients in the OFA group (odds ratio, 5.55; 95% CI, 2.01-15.33; P = .001). In addition, the OFA group included fewer patients with side effects, including nausea, vomiting, and pruritus, within 48 hours after surgery.

CONCLUSIONS

Replacement of opioids by esketamine, intraoperatively as intravenous injection and epidural infusion and postoperatively as epidural infusion, reduces the incidence of mild chronic postoperative pain and side effects in patients after VATS.

Effects of opioid-free total intravenous anesthesia on postoperative nausea and vomiting after treatments of lower extremity wounds: protocol for a randomized double-blind crossover trial

BACKGROUND

Postoperative nausea and vomiting (PONV) are common after general anesthesia and surgery. This study aims to compare the effects of total intravenous opioid-free anesthesia (OFA) with conventional opioid-based anesthesia (OBA) on PONV in patients following treatments for wounds of lower extremities.

METHODS

This randomized, double-blind, crossover trial will include a total of 72 adult patients scheduled for at least two separate surgical treatments of lower extremity wounds under general anesthesia. Patients will be randomized to 1 of 2 anesthesia sequences of OFA and OBA. Patients in sequence 1 will receive OFA in the first treatment procedure and OBA in the second procedure, while patients in sequence 2 will receive the two anesthesia regimens in the reverse order. The washout period is at least 5 days. OFA will be delivered with intravenous esketamine, lidocaine, dexmedetomidine, and propofol. OBA will be delivered with intravenous sufentanil and propofol. The primary endpoint is the incidence of PONV within the first 48 h postoperatively. The secondary endpoints are the severity of PONV, antiemetic rescue therapy, postoperative pain scores, the worst pain, need for rescue analgesia, postoperative sedation, hypotension, bradycardia, hypertension, tachycardia, hypoxemia, psychotomimetic or dissociative effects, time to extubation, and length of postanesthesia care unit stay. Patients who complete two surgical procedures with designated anesthesia regimens will be included in the final analyses.

DISCUSSION

This crossover trial will determine whether total intravenous OFA reduces PONV in patients following treatments for lower extremity wounds. The results of this trial will also represent an important step to understand the benefits and possible risks of OFA in surgical patients.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200061511).

The effect of opioid-free anaesthesia on the quality of recovery after endoscopic sinus surgery: A multicentre randomised controlled trial

BACKGROUND

It remains to be determined whether opioid-free anaesthesia (OFA) is consistently effective for different types of surgery.

OBJECTIVES

The current study hypothesised that OFA could effectively inhibit intraoperative nociceptive responses, reduce side effects associated with opioid use, and improve the quality of recovery (QoR) in endoscopic sinus surgery (ESS).

DESIGN

A multicentre randomised controlled study.

SETTING

Seven hospitals participated in this multicentre trial from May 2021 to December 2021.

PATIENTS

Of the 978 screened patients who were scheduled for elective ESS, 800 patients underwent randomisation, and 773 patients were included in the analysis; 388 patients in the OFA group and 385 patients in the opioid anaesthesia group.

INTERVENTIONS

The OFA group received balanced anaesthesia with dexmedetomidine, lidocaine, propofol and sevoflurane; the opioid anaesthesia group received opioid-based balanced anaesthesia using sufentanil, remifentanil, propofol and sevoflurane.

OUTCOME MEASURES

The primary outcome was 24-h postoperative QoR as evaluated by the Quality of Recovery-40 questionnaire. The key secondary outcomes were episodes of postoperative pain and postoperative nausea and vomiting (PONV).

RESULTS

A significant difference (P = 0.0014) in the total score of 24-h postoperative Quality of Recovery-40 was found between the OFA group, median [interquartile range], 191 [185 to 196] and the opioid anaesthesia group (194 [187 to 197]). There were significant differences between the opioid anaesthesia group and the OFA group in the numerical rating scale score for pain after surgery at 30 min (P  = 0.0017), 1 h (P  = 0.0052), 2 h (P  = 0.0079) and 24 h (P = 0.0303). The difference in the area under the curve of pain scale scores between the OFA group (24.2 [3.0 to 47.5]) and the opioid anaesthesia group (11.5 [1.0 to 39.0]) was significant (P = 0.0042). PONV occurred in 58 of 385 patients (15.1%) in the opioid anaesthesia group compared with 27 of 388 patients (7.0%) in the OFA group, suggesting the incidence of PONV in the OFA group was significantly lower than in the opioid anaesthesia group (P  = 0.0021).

CONCLUSION

OFA can provide good intraoperative analgesia and postoperative recovery quality as effectively as conventional opioid anaesthesia in patients undergoing ESS. OFA can be an alternative option in the pain management of ESS.

TRIAL REGISTRATION

The study was registered at the Chinese Clinical Trial Registry (ChiCTR2100046158; registry URL: http://www.chictr.org.cn/enIndex.aspx.).

General anesthesia with S-ketamine improves the early recovery and cognitive function in patients undergoing modified radical mastectomy: a prospective randomized controlled trial

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common postoperative disorder that is frequently observed after general anesthesia, which seriously threatens the quality of patients' life. Existing studies have demonstrated that S-ketamine plays an important role in improving neuroinflammation. This trial aimed to explore the effects of S-ketamine on quality of recovery and cognitive function in patients following modified radical mastectomy (MRM).

METHODS

Ninety patients aged 45 to 70 years with ASA grades of I or II, who underwent MRM, were selected. Patients were randomly assigned to the S-ketamine or control group. In the S-ketamine group, patients were induced with S-ketamine instead of sufentanil and maintained with S-ketamine and remifentanil. In the control group, patients were induced with sufentanil and maintained with remifentanil. The primary outcome was the Mini-Mental State Examination (MMSE) and Quality of Recovery-15 (QoR-15) score. Secondary outcomes including visual analog scale (VAS) score, cumulative propofol and opioids consumption, post anesthesia care unit (PACU) recovery time, occurrence of remedial analgesia, postoperative nausea and vomiting (PONV), other adverse events, as well as patient satisfaction.

RESULTS

The global QoR-15 scores at postoperative day 1 (POD1) were significantly higher in the S-ketamine group than in the control group (124 [119.5-128.0] vs. 119 [114.0-123.5], P = 0.002), with a median difference of 5 points (95% confidence interval [CI] [-8 to -2]). Similarly, the global QoR-15 scores at postoperative day 2 (POD2) in the S-ketamine group were significantly higher than in the control group (140.0 [133.0-145.0] vs. 132.0 [126.5-141.5], P = 0.004). In addition, among the five subcomponents of the 15-item scale, S-ketamine group had a higher score in terms of physical comfort, pain, and emotional state both at POD1 and POD2. In terms of MMSE score, S-ketamine could promote the recovery of postoperative cognitive function at POD1, but not at POD2. Furthermore, the consumption of opioids, VAS score, and remedial analgesia in the S-ketamine group decreased significantly.

CONCLUSIONS

Collectively, our findings support that general anesthesia with S-ketamine as a potential strategy showed high safety and could not only improve the quality of recovery mainly through improving pain, physical comfort, and emotional state but also promote the recovery of cognitive function on POD1 in patients undergoing MRM.

TRIAL REGISTRATION

The study was registered in the Chinese Clinical Trial Registry (registration No:ChiCTR2200057226, Date of registration: 04/03/2022).

Acupuncture combined with ondansetron for prevention of postoperative nausea and vomiting in high-risk patients undergoing laparoscopic gynaecological surgery: A randomised controlled trial

BACKGROUND

Consensus guidelines recommend the use of multiple antiemetics as prophylaxis in patients at high risk of postoperative nausea and vomiting (PONV), but the evidence regarding combining acupuncture and antiemetics as a multimodal approach was of very low quality.

OBJECTIVE

This study aimed to assess the effect of combinations of acupuncture with ondansetron versus ondansetron alone for PONV prophylaxis in women at a high risk.

METHODS

This parallel, randomised controlled trial was conducted in a tertiary hospital in China. Patients who had three or four PONV risk factors on the Apfel simplified risk score, undergoing elective laparoscopic gynaecological surgery for benign pathology, were recruited. Patients in the combination group received two sessions of acupuncture treatment and 8 mg intravenous ondansetron, whereas those in the ondansetron group received ondansetron alone. The primary outcome was the incidence of PONV within 24 h postoperatively. Secondary outcomes included the incidence of postoperative nausea, postoperative vomiting, adverse events etc. RESULTS: Between January and July 2021, a total of 212 women were recruited, 91 patients in the combination group and 93 patients in the ondansetron group were included in the modified intention-to-treat analysis. In the first 24 h postoperatively, 44.0% of the patients in the combination group and 60.2% of the patients in the ondansetron group experienced nausea, vomiting, or both (difference, -16.3% [95% CI, -30.5 to -2.0]; risk ratio, 0.73 [95% CI, 0.55-0.97]; p = 0.03). However, the results of the secondary outcomes showed that compared to ondansetron alone, acupuncture together with ondansetron was only effective in reducing nausea but did not have a significant impact on vomiting. The incidence of adverse events was similar between the groups.

CONCLUSION

Acupuncture combined with ondansetron as a multimodal prophylaxis approach is more effective than ondansetron alone in preventing postoperative nausea in high-risk patients.

A Novel Opioid-Sparing Analgesia Following Thoracoscopic Surgery: A Non-Inferiority Trial

Purpose

This randomized, non-inferiority study aimed to observe the feasibility of opioid-sparing analgesia based on modified intercostal nerve block (MINB) following thoracoscopic surgery.

Patients and Methods

60 patients scheduled for single-port thoracoscopic lobectomy were randomized to the intervention group or control group. After MINB was performed in both groups at the end of the surgery, the intervention group received patient controlled-intravenous analgesia (PCIA) of dexmedetomidine 0.05 µg/kg/h for 72 h after surgery, and the control group received conventional PCIA of sufentanil 3 µg/kg for 72 h. The primary outcome was a visual analog scale (VAS) on coughing 24 h after surgery. Secondary outcomes included the time to first analgesic request, pressing times of PCIA, time to first flatus, and hospital stay.

Results

There was no difference in the cough-VAS at 24 h (median [interquartile range]) between the intervention group [3 (2-4)] and control group [3 (2-4), P = 0.36]. The median difference (95% CI) in the cough-VAS at 24 h was [0 (0 to 1), P = 0.36]. There was no significant difference in the time to first analgesic request, pressing times of PCIA, and hospital stay between groups (P > 0.05). A significant decrease in time to first flatus was observed in the intervention group (P < 0.01).

Conclusion

Opioid-sparing analgesia provided safe and analogous postoperative analgesia with a shortened time to first flatus, compared with sufentanil-based analgesia in thoracoscopic surgery. This might be a novel method recommended for thoracoscopic surgery.

Opioid-Free Anesthesia for Open Radical Cystectomy Is Feasible and Accelerates Return of Bowel Function: A Matched Cohort Study

The aim of this study was to evaluate the feasibility of opioid-free anesthesia (OFA) in open radical cystectomy (ORC) with urinary diversion and to assess the impact on recovery of gastrointestinal function. We hypothesized that OFA would lead to earlier recovery of bowel function. A total of 44 patients who underwent standardized ORC were divided into two groups (OFA group vs. control group). In both groups, patients received epidural analgesia (OFA group: bupivacaine 0.25%, control group: bupivacaine 0.1%, fentanyl 2 mcg/mL, and epinephrine 2 mcg/mL). The primary endpoint was time to first defecation. Secondary endpoints were incidence of postoperative ileus (POI) and incidence of postoperative nausea and vomiting (PONV). The median time to first defecation was 62.5 h [45.8-80.8] in the OFA group and 118.5 h [82.6-142.3] (p < 0.001) in the control group. With regard to POI (OFA group: 1/22 patients (4.5%); control group: 2/22 (9.1%)) and PONV (OFA group: 5/22 patients (22.7%); control group: 10/22 (45.5%)), trends but no significant results were found (p = 0.99 and p = 0.203, respectively). OFA appears to be feasible in ORC and to improve postoperative functional gastrointestinal recovery by halving the time to first defecation compared with standard fentanyl-based intraoperative anesthesia.

Effects of Ketamine Infusion on Breathing and Encephalography in Spontaneously Breathing ICU Patients

BACKGROUND

Preclinical studies suggest that ketamine stimulates breathing. We investigated whether adding a ketamine infusion at low and high doses to propofol sedation improves inspiratory flow and enhances sedation in spontaneously breathing critically ill patients.

METHODS

In this prospective interventional study, twelve intubated, spontaneously breathing patients received ketamine infusions at 5 mcg/kg/min, followed by 10 mcg/kg/min for 1 h each. Airway flow, pressure, and esophageal pressure were recorded during a spontaneous breathing trial (SBT) at baseline, and during the SBT conducted at the end of each ketamine infusion regimen. SBT consisted of one-minute breathing with zero end-expiratory pressure and no pressure support. Changes in inspiratory flow at the pre-specified time points were assessed as the primary outcome. Ketamine-induced change in beta-gamma electroencephalogram power was the key secondary endpoint. We also analyzed changes in other ventilatory parameters respiratory timing, and resistive and elastic inspiratory work of breathing.

RESULTS

Ketamine infusion of 5 and 10 mcg/kg/min increased inspiratory flow (median, IQR) from 0.36 (0.29-0.46) L/s at baseline to 0.47 (0.32-0.57) L/s and 0.44 (0.33-0.58) L/s, respectively (p = .013). Resistive work of breathing decreased from 0.4 (0.1-0.6) J/l at baseline to 0.2 (0.1-0.3) J/l after ketamine 10 mcg/kg/min (p = .042), while elastic work of breathing remained unchanged. Electroencephalogram beta-gamma power (19-44 Hz) increased compared to baseline (p < .01).

CONCLUSIONS

In intubated, spontaneously breathing patients receiving a constant rate of propofol, ketamine increased inspiratory flow, reduced inspiratory work of breathing, and was associated with an "activated" electroencephalographic pattern. These characteristics might facilitate weaning from mechanical ventilation.

Postoperative/postdischarge nausea and vomiting: evidence-based prevention and treatment

PURPOSE OF REVIEW

Postoperative/postdischarge nausea and vomiting (PONV/PDNV) remains a relevant issue in perioperative care. Especially in outpatient surgery, PONV can prevent discharge or lead to unplanned readmission.

RECENT FINDINGS

Evidence on prophylaxis and treatment of PONV is growing, but implementation remains poor.

SUMMARY

A liberal, universal PONV management is now endorsed by the guidelines. Specific evidence concerning prevention and (at-home) treatment of PDNV is still scarce.

Application of opioid-free general anesthesia for gynecological laparoscopic surgery under ERAS protocol: a non-inferiority randomized controlled trial

BACKGROUND

Enhanced recovery after surgery (ERAS) is now widely used in various surgical fields including gynecological laparoscopic surgery, but the advantages of opioid-free anesthesia (OFA) in gynecological laparoscopic surgery under ERAS protocol are inexact.

AIMS

This study aims to assess the effectiveness and feasibility of OFA technique versus traditional opioid-based anesthesia (OA) technique in gynecological laparoscopic surgery under ERAS.

METHODS

Adult female patients aged 18 ~ 65 years old undergoing gynecological laparoscopic surgery were randomly divided into OFA group (Group OFA, n = 39) with esketamine and dexmedetomidine or OA group (Group OA, n = 38) with sufentanil and remifentanil. All patients adopted ERAS protocol. The primary outcome was the area under the curve (AUC) of Visual Analogue Scale (VAS) scores (AUC_VAS) postoperatively. Secondary outcomes included intraoperative hemodynamic variables, awakening and orientation recovery times, number of postoperative rescue analgesia required, incidence of postoperative nausea and vomiting (PONV) and Pittsburgh Sleep Quality Index (PSQI) perioperatively.

RESULTS

AUC_VAS was (Group OFA, 16.72 ± 2.50) vs (Group OA, 15.99 ± 2.72) (p = 0.223). No difference was found in the number of rescue analgesia required (p = 0.352). There were no between-group differences in mean arterial pressure (MAP) and heart rate (HR) (p = 0.211 and 0.659, respectively) except MAP at time of surgical incision immediately [(Group OFA, 84.38 ± 11.08) vs. (Group OA, 79.00 ± 8.92), p = 0.022]. Times of awakening and orientation recovery in group OFA (14.54 ± 4.22 and 20.69 ± 4.92, respectively) were both longer than which in group OA (12.63 ± 3.59 and 18.45 ± 4.08, respectively) (p = 0.036 and 0.033, respectively). The incidence of PONV in group OFA (10.1%) was lower than that in group OA (28.9%) significantly (p = 0.027). The postoperative PSQI was lower than the preoperative one in group OFA (p = 0.013).

CONCLUSION

In gynecological laparoscopic surgery under ERAS protocol, OFA technique is non-inferior to OA technique in analgesic effect and intraoperative anesthesia stability. Although awakening and orientation recovery times were prolonged compared to OA, OFA had lower incidence of PONV and improved postoperative sleep quality.

TRIAL REGISTRATION

ChiCTR2100052761, 05/11/2021.

Opioid-free anesthesia for postoperative recovery after video-assisted thoracic surgery: A prospective, randomized controlled trial

Purpose

Opioid-based anesthesia is a traditional form of anesthesia that has a significant analgesic effect; however, it can cause nausea, vomiting, delirium, and other side effects. Opioid-free anesthesia with dexmedetomidine and lidocaine has attracted widespread attention. This study aimed to compare the effects of opioid-free and opioid-based anesthesia (OFA and OBA, respectively) on postoperative recovery in patients who had undergone video-assisted thoracic surgery.

Methods

Eighty patients undergoing video-assisted thoracic surgery were assigned to receive either opioid-free anesthesia (OFA group) or opioid-based anesthesia (OBA group) according to random grouping. The primary outcome of the study was the quality of recovery-40 scores (QoR-40) 24 h postoperatively. The secondary outcome measure was numerical rating scale (NRS) scores at different times 48 h postoperatively. In addition to these measurements, other related parameters were recorded.

Results

Patients who received opioid-free anesthesia had higher QoR-40 scores (169.1 ± 5.1 vs. 166.8 ± 4.4, p = 0.034), and the differences were mainly reflected in their comfort and emotional state; however, the difference between the two groups was less than the minimal clinically important difference of 6.3. We also found that the NRS scores were lower in the OFA group than in the OBA group at 0.5 h (both p < 0.05) and 1 h (both p < 0.05) postoperatively and the cumulative 0-24 h postoperative dosage of sufentanil in the OBA group was higher than that in the OFA group (p = 0.030). There were no significant differences in postoperative nausea and vomiting (PONV) (p = 0.159). No surgical or block complications were observed between the groups.

Conclusion

Opioid-free analgesia potentially increased the postoperative recovery in patients who underwent video-assisted thoracic surgery.

Trial registration

The study protocol was registered in the Chinese Clinical Trial Register under the number ChiCTR2100045344 (http://www.chictr.org.cn/showproj.aspx?proj=125033) on April 13, 2021.

Effect of balanced opioid-free anaesthesia on postoperative nausea and vomiting after video-assisted thoracoscopic lung resection: protocol for a randomised controlled trial

INTRODUCTION

Opioid-free anaesthesia (OFA) may reduce opioid-related side effects such as postoperative nausea and vomiting (PONV) and hyperalgesia. This study aims to investigate the effects of balanced OFA on PONV and pain outcomes in patients undergoing video-assisted thoracoscopic surgery (VATS).

METHODS AND ANALYSIS

This randomised controlled trial will be conducted at the First Affiliated Hospital of Soochow University in Suzhou, China. A total of 120 adults scheduled for VATS lung resection will be randomly assigned with a 1:1 ratio to either an OFA group or a control group, stratified by sex (n=60 in each group). Patients will receive balanced anaesthesia with esketamine, dexmedetomidine and sevoflurane (the OFA group), or sufentanil and sevoflurane (the control group). All patients will receive PONV prophylaxis with intraoperative dexamethasone and ondansetron. Multimodal analgesia consists of intraoperative flurbiprofen axetil, ropivacaine infiltration at the end of surgery and postoperative patient-controlled sufentanil. The primary outcome is the incidence of PONV within 48 hours after surgery. Secondary outcomes are nausea, vomiting, need for antiemetic therapy, pain scores at rest and while coughing, postoperative sufentanil consumption, need for rescue analgesia, length of post-anaesthesia care unit stay, length of postoperative hospital stay, and 30-day and 90-day post-surgical pain and mortality. Safety outcomes are hypotension, bradycardia, hypertension, tachycardia, interventions for haemodynamic events, level of sedation, headache, dizziness, nightmare and hallucination. All analyses will be performed in the modified intention-to-treat population.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Ethics Committee of the First Affiliated Hospital of Soochow University (2022-042). All patients will provide written informed consent. The results of this study will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2200059710).

Low-dose naloxone for prophylaxis of sufentanil-induced choking and postoperative nausea and vomiting

Sufentanil, a potent opioid, serves as the first option for perioperative analgesia owing to its analgesic effect, long duration and stable hemodynamics, whereas its side effects frequently blunt its application. The intravenous (IV) injection of sufentanil during anesthesia induction has high incidence of choking or bucking reaction, which is defined as sufentanil-induced cough (SIC). Moreover, postoperative nausea and vomiting (PONV) is a common and stressful complication, which is also related to the usage of opioid. High incidence of PONV is reported in the patients with SIC. Hence, we sought to determine whether naloxone, an opioid antagonist, at low dose would decrease the incidences of SIC and PONV. 216 female patients undergoing gynecological laparoscopic operation (<2 h) under general anesthesia were recruited in this study, and randomly assigned into two groups: Group N (patients receiving naloxone and Group C (patients receiving vehicle). Sufentanil (0.5 μg/kg within 5 s) was given in anesthesia induction, and low-dose naloxone (1.25 μg/kg) or identical vehicle was initially injected 5 min prior to induction, with the incidence and severity of SIC estimated. Subsequently, naloxone or vehicle was continuously infused at the rate of 0.5 μg/kg/h in the initiation of operation until the end of the operation, and the transverse abdominal fascia block (TAP) was performed for postoperative analgesia. The PONV profiles such as incidence and the severity, grading, and the frequencies of antiemetic usage within 24 h were evaluated, with VAS scores and remedial measures for analgesia during the first 24 h postoperatively were recorded. Our results revealed that one bolus of low-dose naloxone prior to the induction significantly mitigated the incidence of SIC, and intraoperative continuous infusion of low-dose naloxone reduced the incidence and the severity of PONV, so that the postoperative VAS scores and further remedial analgesia were not altered. These results not only provide clinical solutions for prophylaxis of SIC and PONV, but also suggests that opioids may act as a key role in both SIC and PONV, whereas opioid antagonist may hit two tasks with one stone. Moreover, further investigations are required to address the underlying mechanism of SIC and PONV. Clinical Trial Registration: [www.chictr.org.cn], identifier [ChiCTR2200064865].

Opioid-reduced anesthesia based on esketamine in gynecological day surgery: a randomized double-blind controlled study

Background

Opioid-reduced anesthesia may accelerate postoperative rehabilitation by reducing opioid-related side effects. The objective was to investigate the feasibility of opioid-reduced general anesthesia based on esketamine and to observe postoperative nausea and vomiting (PONV), postoperative pain, hemodynamics and other adverse reactions in gynecological day surgery compared with the traditional opioid-based anesthesia program.

Method

This study was conducted as a prospective parallel-group randomized controlled trial. A total of 141 adult women undergoing gynecological day surgery were included. Patients were randomly assigned to receive traditional opioid-based anesthesia (Group C) with alfentanil, or opioid-reduced anesthesia (a moderate-opioid group (Group MO) and low-opioid group (Group LO) with esketamine and alfentanil). For anesthesia induction, the three groups received 20, 20, 10 μg/kg alfentanil respectively and Group LO received an additional 0.2 mg/kg esketamine. For maintenance of anesthesia, the patients in Group C received 40 μg/kg/h alfentanil, and those in Group MO and Group LO received 0.5 mg/kg/h esketamine.

Results

Patients in the three groups had comparable clinical and surgical data. A total of 33.3% of patients in Group C, 18.4% of patients in Group MO and 43.2% of patients in Group LO met the primary endpoint (p = 0.033), and the incidence of nausea within 24 hours after surgery in Group MO was lower than in Group LO (p < 0.05). The extubation time, median length of stay in the hospital after surgery and visual analog scale (VAS) of postoperative pain were equivalent in the three groups. The frequencies of adverse hemodynamic events in the MO 1(0, 2) and LO 0(0, 1) groups were significantly decreased (p < 0.05). Compared with Group C, the median length of stay in the postanesthesia care unit (PACU) in Group LO was increased, 60.0 (36.25, 88.75) vs. 42.5 (25, 73.75) minutes (p < 0.05).

Conclusions

Opioid-reduced anesthesia based on esketamine is feasible and provides effective analgesia for patients. Esketamine provided a positive analgesic effect and the opioid-reduced groups showed more stable hemodynamics. However, less or no use of opioids did not result in a more comfortable prognosis.

Trial registration

This study was registered at Chictr.org.cn (NO. ChiCTR2100053153); November 13, 2021.

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.

Opioid-free total intravenous anesthesia for thyroid and parathyroid surgery: Protocol for a randomized, double-blind, controlled trial

Background

Opioid-free anesthesia (OFA) may improve postoperative outcomes by reducing opioid-related adverse effects. This study aims to evaluate the effects of OFA on postoperative nausea and vomiting (PONV), postoperative pain, and 30-day outcomes after thyroid and parathyroid surgery.

Methods

This two-center, randomized, double-blind, controlled trial will include 400 adult patients scheduled for thyroid and parathyroid surgery. Patients will be randomly assigned, 1:1 and stratified by sex and site, to an OFA group (esketamine, lidocaine, and dexmedetomidine) or a control group (opioid-based anesthesia with sufentanil). All patients will receive propofol-based total intravenous anesthesia and PONV prophylaxis with dexamethasone and ondansetron. The primary outcome is the incidence of PONV (defined as experiencing any event of nausea, retching, or vomiting) during the first 48 h postoperatively. The secondary outcomes include the severity of PONV, antiemetic rescue therapy, pain scores at rest and while coughing, need for rescue analgesia, perioperative adverse effects related to anesthetics or analgesics (hypotension, bradycardia, hypertension, tachycardia, desaturation, dizziness, headache, hallucination, and nightmare), time to extubation, length of post-anesthesia care unit stay, length of postoperative hospital stay, patient satisfaction, and a composite of 30-day major adverse events (myocardial infarction, cardiac arrest, cerebrovascular accident, coma, acute renal failure, pulmonary embolism, sepsis, septic shock, deep neck space infection, reintubation, reoperation, blood transfusion, failure to wean off ventilator, and death). Analyses will be performed in the modified intention-to-treat population.

Discussion

We hypothesize that our OFA regimen reduces PONV after thyroid and parathyroid surgery. We will also investigate whether OFA leads to improvements in postoperative pain and major adverse events. Our results will offer evidence for optimizing anesthesia regimens in patients who undergo thyroid and parathyroid surgical procedures.

Clinical trial registration

http://www.chictr.org.cn, identifier: ChiCTR2200059656.

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.

Impact of Opioid-Free Anesthesia on Analgesia and Recovery Following Bariatric Surgery: a Meta-Analysis of Randomized Controlled Studies

This meta-analysis aimed at exploring the impact of opioid-free anesthesia (OFA) on pain score and opioid consumption in patients undergoing bariatric surgery (BS). Literature search identified eight eligible trials. Forest plot revealed a significantly lower pain score (mean difference (MD) =  - 0.96, p = 0.0002; 318 patients), but not morphine consumption (MD =  - 5.85 mg, p = 0.1; 318 patients) at postoperative 24 h in patients with OFA than in those without. Pooled analysis also showed a lower pain score (p = 0.002), morphine consumption (p = 0.0003) in the postanesthetic care unit, and risk of postoperative nausea/vomiting (p = 0.0003) in the OFA group compared to the controls. In conclusion, this meta-analysis demonstrated that opioid-free anesthesia improved pain outcomes immediately and at 24 h after surgery without a beneficial impact on opioid consumption at postoperative 24 h. KEY POINTS: • Roles of opioid-free anesthesia (OFA) in bariatric surgery (BS) were investigated. • Outcomes included postoperative pain score, opioid use, and nausea/vomiting risk. • OFA was associated with lower 24-h pain score but not opioid consumption. • Lower pain score and opioid consumption were noted in the postanesthetic care unit. • OFA correlated with a lower risk of postoperative nausea/vomiting.

An Opioid-Sparing Strategy for Laparoscopic Sleeve Gastrectomy: A Retrospective Matched Case-Controlled Study in China

Background: Opioid-sparing anesthesia may enhance postoperative recovery by reducing opioid-related side effects. The present study was to evaluate the effect of an opioid-sparing strategy in bariatric surgery.

Methods: This study was conducted as a retrospective matched case-controlled (1:1) study. A total of 44 patients receiving either an opioid-based approach (OBA group) or an opioid-sparing strategy (OSA group) who under laparoscopic sleeve gastrectomy were included between May 2017 and October 2020. The primary outcome was the postoperative hospital length of stay (PLOS). Secondary outcomes were the hospital costs, operative opioid consumption, time to recovery, postoperative pain score at rest and rescue antiemetic administered in the PACU.

Results: The clinical demographic and operative data in both groups were comparable. There were no significant differences between the two groups in the PLOS (OSA vs. OBA: 6.18 ± 0.23 days vs. 6.73 ± 0.39 days, p = 0.24). Compared to the OBA group, opioid consumption in the OSA group was significantly decreased (48.79 ± 4.85 OMEs vs. 10.57 ± 0.77 OMEs, p < 0.001). There were no significant differences in the hospital costs, time to recovery, and rescue antiemetic administered, the incidence of intravenous opioids and vasopressor use in the PACU.

Conclusion: The opioid-sparing anesthesia for laparoscopic sleeve gastrectomy was feasible but did not decrease the PLOS.

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

Background

Breast cancer surgery is usually managed using opioid-inclusive anesthesia (OIA), although opioids are associated with several adverse events, including nausea, vomiting, and constipation. Multimodal opioid-free anesthesia (OFA) has been introduced to reduce the incidence of these side effects. In this single-center retrospective study, we investigated whether ketamine, combined with magnesium and clonidine, could effectively control postoperative pain in patients undergoing quadrantectomy, while reducing postoperative nausea and vomiting (PONV).

Results

A total of 89 patients submitted to quadrantectomy were included and divided into an OFA group (38 patients) and an OIA group (51 patients) according to the received anesthetic technique. Analgesia in the OIA group was based on an intraoperative infusion of remifentanil, and analgesia in the OFA consisted of an intraoperative infusion of ketamine and magnesium sulfate. Postoperative pain in both groups was managed with nonsteroidal anti-inflammatory drugs (NSAIDs) and paracetamol. Postoperative pain, assessed with the numeric rating scale (NRS), requirements for additional analgesics, the incidence of PONV, and patient satisfaction evaluated using a QoR-40 questionnaire were compared between the two groups. Levels of pain at 30 min and 6, 12, and 24 h after surgery; number of paracetamol rescue doses; and the incidence of PONV were lower in the OFA group (p <0.05). Patient satisfaction was comparable in the two groups.

Conclusions

A combination of ketamine, magnesium, and clonidine could be more effective than opioid-based analgesia in reducing postoperative pain and lowering PONV occurrence after quadrantectomy for breast cancer.