Opioid-Free Anesthesia in Bariatric Surgery: a Propensity Score-Matched Analysis

Effect of an opioid-free anesthetic on postoperative opioid consumption after laparoscopic bariatric surgery: a prospective, single-blinded, randomized controlled trial

INTRODUCTION

Opioid administration has the benefit of providing perioperative analgesia but is also associated with adverse effects. Opioid-free anesthesia (OFA) may reduce postoperative opioid consumption and adverse effects after laparoscopic bariatric surgery. In this randomized controlled study, we hypothesized that an opioid-free anesthetic using lidocaine, ketamine, and dexmedetomidine would result in a clinically significant reduction in 24-hour postoperative opioid consumption when compared with an opioid-inclusive technique.

METHODS

Subjects presenting for laparoscopic or robotic bariatric surgery were randomized in a 1:1 ratio to receive either standard opioid-inclusive anesthesia (group A: control) or OFA (group B: OFA). The primary outcome was opioid consumption in the first 24 hours postoperatively in oral morphine equivalents (OMEs). Secondary outcomes included postoperative pain scores, patient-reported incidence of opioid-related adverse effects, hospital length of stay, patient satisfaction, and ongoing opioid use at 1 and 3 months after hospital discharge.

RESULTS

181 subjects, 86 from the control group and 95 from the OFA group, completed the study per protocol. Analysis of the primary outcome showed no significant difference in total opioid consumption at 24 hours between the two treatment groups (control: 52 OMEs vs OFA: 55 OMEs, p=0.49). No secondary outcomes showed statistically significant differences between groups.

CONCLUSIONS

This study demonstrates that an OFA protocol using dexmedetomidine, ketamine, and lidocaine for laparoscopic or robotic bariatric surgery was not associated with a reduction in 24-hour postoperative opioid consumption when compared with an opioid-inclusive technique using fentanyl.

Effect of opioid-free versus opioid-based strategies during multimodal anaesthesia on postoperative morphine consumption after bariatric surgery: a randomised double-blind clinical trial

Background

The efficacy and safety of opioid-free anaesthesia during bariatric surgery remain debated, particularly when administering multimodal analgesia. As multimodal analgesia has become the standard of care in many centres, we aimed to determine if such a strategy coupled with either dexmedetomidine (opioid-free anaesthesia) or remifentanil with a morphine transition (opioid-based anaesthesia), would reduce postoperative morphine requirements and opioid-related adverse events.

Methods

In this prospective double-blind study, 172 class III obese patients having laparoscopic gastric bypass surgery were randomly allocated to receive either sevoflurane-dexmedetomidine anaesthesia with a continuous infusion of lidocaine and ketamine (opioid-free group) or sevoflurane-remifentanil anaesthesia with a morphine transition (opioid-based group). Both groups received at anaesthesia induction a bolus of magnesium, lidocaine, ketamine, paracetamol, diclofenac, and dexamethasone. The primary outcome was 24-h postoperative morphine consumption. Secondary outcomes included postoperative quality of recovery (QoR40), incidence of hypoxaemia, bradycardia, and postoperative nausea and vomiting (PONV).

Results

Eighty-six patients were recruited in each group (predominantly women, 70% had obstructive sleep apnoea). There was no significant difference in postoperative morphine consumption (median [inter-quartile range]: 16 [13-26] vs 15 [10-24] mg, P=0.183). The QoR40 up to postoperative day 30 did not differ between groups, but PONV was less frequent in the opioid-free group (37% vs 59%, P=0.005). Hypoxaemia and bradycardia were not different between groups.

Conclusions

During bariatric surgery, a multimodal opioid-free anaesthesia technique did not decrease postoperative morphine consumption when compared with a multimodal opioid-based strategy. Quality of recovery did not differ between groups although the incidence of PONV was less in the opioid-free group.

Clinical trial registration

NCT05004519.

Laparoscopic-Assisted Transversus Abdominis Plane (TAP) Block Versus Port-Site Infiltration with Local Anesthetics in Bariatric Surgery: a Double-Blind Randomized Controlled Trial

BACKGROUND

The transversus abdominis plane (TAP) block has shown great potential usefulness in the management of postoperative pain; however, there is lacking evidence regarding its use in bariatric surgery. This randomized double-blind trial was aimed at comparing the effectiveness of the TAP block and port-site infiltration (PSI) in patients undergoing bariatric surgery.

METHODS

We included patients ≥ 18 years old undergoing bariatric surgery. From July 2020 to July 2021, all eligible patients were randomized to receive either laparoscopic-assisted TAP block or PSI. Demographic and clinical data were collected and analyzed.

RESULTS

During the study period, we included 113 patients. Fifty-one were allocated to the TAP block group and 62 to the PSI group. The mean age was 47.9 ± 11.2 years, 88 (77.9%) patients were female, and mean BMI was 40.5 ± 5.9 kg/m2. Operative time was 110 ± 42 min vs. 114 ± 41 min in the TAP block and PSI groups (p = 0.658). At 24 h after surgery, pain on the VAS was 2.5 ± 2.6 vs. 2.3 ± 2.1 (p = 0.661). No significant difference between the groups was noted at 3, 6, 12, and 18 h. Also, opioid and antiemetic consumption, the length of stay (3.4 ± 1.5 days vs. 3.2 ± 1.1 days, p = 0.392), and satisfaction score (154 ± 10 pts vs. 154 ± 16 pts, p = 0.828) were similar in the two groups.

CONCLUSIONS

Patients undergoing bariatric surgery and receiving either the TAP block or the PSI had similar postoperative pain, nausea, length of stay, and satisfaction. As PSI is technically easier and more reproducible, it might be the first choice for postoperative multimodal analgesia in bariatric surgery.

Comparison between multimodal and intraoperative opioid free anesthesia for laparoscopic sleeve gastrectomy: a prospective, randomized study

Anesthesia for laparoscopic sleeve gastrectomy and perioperative management remains a challenge. Several clinical studies indicate that opioid-free anesthesia (OFA) may be beneficial, but there is no consensus on the most optimal anesthesia technique in clinical practice. The aim of our study was to assess the potential benefits and risks of intraoperative OFA compared to multimodal analgesia (MMA) with remifentanil infusion. In a prospective, randomized study, we analyzed 59 patients' data. Primary outcome measures were oxycodone consumption and reported pain scores (numerical rating scale, NRS) at 1, 6, 12, and 24th hours after surgery. Postoperative sedation on the Ramsay scale, nausea and vomiting on the PONV impact scale, desaturation episodes, pruritus, hemodynamic parameters, and hospital stay duration were also documented and compared. There were no significant differences in NRS scores or total 24-h oxycodone requirements. In the first postoperative hour, OFA group patients needed an average of 4.6 mg of oxycodone while the MMA group 7.72 mg (p = 0.008, p < 0.05 statistically significant). The PONV impact scale was significantly lower in the OFA group only in the first hour after the operation (p = 0.006). Patients in the OFA group required higher doses of ephedrine 23.67 versus 15.69 mg (p = 0.039) and more intravenous fluids 1160 versus 925.86 ml (p = 0.007). The mode of anesthesia did not affect the pain scores or the total dose of oxycodone in the first 24 postoperative hours. Only in the first postoperative hour were an opioid-sparing effect and reduction of PONV incidence seen in the OFA group when compared with remifentanil-based anesthesia. However, patients in the OFA group showed significantly greater hemodynamic lability necessitating higher vasopressor doses and more fluid volume.

Comparison of the Efficacy of Opioid-Free Anesthesia With Conventional Opioid-Based Anesthesia for Nasal Surgeries - A Prospective Randomized Parallel Arm Triple-Blinded Study

Introduction In the setting of nasal surgeries, the use of opioid-free anesthesia involving the use of dexmedetomidine, and lignocaine is being investigated as a potential alternative to opioids. This combination of drugs provides sympatholysis, pain relief, and sedative properties, thereby aiming at reducing the negative effects commonly associated with opioid usage. The objective of this study is to evaluate and compare the effectiveness of opioid-free anesthesia using dexmedetomidine and lignocaine versus conventional opioid anesthesia with fentanyl for nasal surgeries. The comparison will be based on the primary outcome of postoperative visual analog scale (VAS) scores. Secondary outcomes assessed were the amount of rescue analgesic consumption, intraoperative sevoflurane usage, intraoperative blood loss, hemodynamic stability, postoperative nausea and vomiting (PONV) scores, and postoperative Ramsay Sedation Scores. Methods A triple-blind, prospective, randomized, parallel arm study in which 48 patients planned for elective nasal surgery were allocated randomly to one of two groups. In the study, the population labeled as Group D, comprising 24 participants, received dexmedetomidine at a dosage of 1 mcg.kg^-1 via intravenous infusion lasting for a duration of 10 minutes prior to the induction of anesthesia. This was followed by a continuous infusion of 0.6 mcg.kg^-1 h^-1 throughout the intraoperative period, and intravenous Lignocaine 1.5 mg.kg^-1 was administered three minutes prior to induction, subsequently an intraoperative infusion of 1.5 mg.kg^-1 h^-1. In Group F, consisting of 24 participants, intravenous fentanyl of 2 mcg.kg^-1 was administered three minutes before the induction. This was subsequently followed by a fentanyl infusion of 0.5 mcg.kg^-1h^-1 in the intraoperative period. Results The study findings indicate that Group D had considerably lower postoperative VAS scores from 30 minutes to two hours compared to Group F (p<0.05). The utilization of sevoflurane during the intraoperative period was comparatively reduced in Group D in order to achieve the desired bispectral index (BIS) range of 40-60 (p<0.01). Mean intraoperative blood loss was also lower in Group D (85 ml) compared to Group F (115 ml )(p<0.01). Additionally, Group D had significantly lower rescue analgesic consumption and lower incidence of PONV up to 60 minutes compared to Group F (P-value <0.01). A statistically significant difference was observed between Group D and Group F in terms of lower mean values of both mean arterial pressure (MAP) and heart rate in Group D (p<0.01). The results indicate that the postoperative sedation scores within the first two hours were significantly greater in Group D compared to Group F (p<0.01). Conclusion The usage of opioid-free anesthesia has been found to be superior to a traditional opioid-based approach in various aspects, including the provision of sufficient pain relief after surgery, maintenance of stable hemodynamics during the operation, and reduction in occurrences of postoperative nausea and vomiting.

Use of sugammadex is associated with reduced incidence and severity of postoperative nausea and vomiting in adult patients with obesity undergoing laparoscopic bariatric surgery: a post-hoc analysis

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common but troublesome complication in patients who undergo laparoscopic bariatric surgery (LBS). Whether sugammadex use is related to the persistent decrease in the occurrence of PONV during postoperative inpatient hospitalization, which is critical for the rehabilitation of patients after LBS, remains unknown.

METHODS

The study was based on a randomized controlled trial conducted in an accredited bariatric centre. A total of 205 patients who underwent LBS were included in the analysis. Univariate analysis and multivariable logistic regression model were used to identify the significant variables related to PONV. Then propensity score matching and inverse probability of treatment weighting (IPTW) were employed to compare outcomes between the sugammadex and neostigmine groups. The primary outcome was the incidence of PONV within 48 h after LBS. The secondary endpoints included the severity of PONV, time to first flatus, need for rescue antiemetic therapy, and water intake.

RESULTS

The incidence of PONV was 43.4% (89/205) within the first 48 h after LBS. In multivariable analysis, sugammadex use (OR 0.03, 95% CI 0.01-0.09, P < 0.001) was an independent protective factor of PONV. After IPTW adjustment, sugammadex use was associated with lower incidence of PONV (OR 0.54, 95% CI 0.48-0.61, P < 0.001), postoperative nausea (PON) (OR 0.77, 95% CI 0.67-0.88, P < 0.001), and postoperative vomiting (POV) (OR 0.60, 95% CI 0.53-0.68, P < 0.001) within postoperative 48 h. The severity of PON as well as the incidence and severity of POV within the first 24 h were also lower in the sugammadex group (all P < 0.05). Reduced need for rescue antiemetic therapy within the first 24 h, increased water intake for both periods, and earlier first passage of flatus were observed in the sugammadex group (all P < 0.05).

CONCLUSIONS

Compared with neostigmine, sugammadex can reduce the incidence and severity of PONV, increase postoperative water intake, and shorten the time to first flatus in bariatric patients during postoperative inpatient hospitalization, which may play a pivotal role in enhanced recovery.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2100052418, http://www.chictr.org.cn/showprojen.aspx?proj=134893 , date of registration: October 25, 2021).

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.