Ketamine and Magnesium: a Successful Combination for Bariatric Surgery

Non-Opioid Analgesics and Adjuvants after Surgery in Adults with Obesity: Systematic Review with Network Meta-Analysis of Randomized Controlled Trials

Background/Objectives: Managing postoperative pain in patients with obesity is challenging. Although using a combination of pain relief methods is recommended for these patients, the true effectiveness of various intravenous non-opioid analgesics and adjuvants in multimodal anesthesia needs to be better defined. Methods: A systematic review and network meta-analysis was performed to evaluate the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, ketamine, α-2 agonists, lidocaine, magnesium, and oral gabapentinoids in adult surgical patients with obesity. The analysis aimed to compare these treatments to a placebo/no treatment or alternative analgesics, with a primary focus on postoperative pain and secondary endpoints including rescue analgesia, postoperative nausea and vomiting (PONV), and recovery quality. English-language randomized controlled trials across PubMed, Scopus, Web of Science, CINAHL, and EMBASE were considered. Quality and evidence certainty were assessed with the RoB 2 tool and GRADE, and data was analyzed with R software. Results: NSAIDs, along with acetaminophen, lidocaine, α-2 agonists, ketamine, and oral gabapentinoids, effectively reduce early postoperative pain. NSAIDs, particularly ibuprofen, as well as acetaminophen, ketamine, and lidocaine, also show benefits in later postoperative stages. Intravenous non-opioid analgesics and adjuvants show some degree of benefit in reducing PONV and the need for rescue analgesic therapy when using α-2 agonists alone or combined with oral gabapentinoids, notably decreasing the likelihood of PONV. Ketamine, lidocaine, and α-2 agonists are shown to enhance postoperative recovery and care quality. Conclusions: Intravenous non-opioid analgesics and adjuvants are valuable in multimodal anesthesia for pain management in adult surgical patients suffering from obesity.

Impact of Perioperative Ketamine on Postoperative Bariatric Surgery Opioid Use and Length of Stay

SETTINGS

Postoperative pain management is an ever-growing challenge with the rise of the opioid crisis. Ketamine is an NMDA channel blocker, considered an alternative to perioperative opioid use; small concentrations are safe. Objective: The primary objective of this study was to evaluate the impact of perioperative ketamine administration on postoperative opioid use and the length of hospital stay in bariatric patients.

METHODS

Four hundred (366) charts were retrospectively reviewed; of those, 187 received ketamine and were placed in the Ketamine group, 179 received standard-of-care pain management and were part of the No-Ketamine group. Data was collected using medical databases from July 2020 to January 2021.

RESULTS

A greater length of stay was recorded in the No-Ketamine group (45.67±20.6 hours) when compared with the Ketamine group (40.6±14.3 hours); P <0.05. The Ketamine group had a mean MME of 17.5±16.5 whereas the No-Ketamine had a mean MME of 22.3±17.7, P <0.05.

CONCLUSIONS

Ketamine may be a feasible alternative to reduce opioid use and hospital length of stay. We believe that ketamine can be an important contribution to ERABS pathways, being responsible for improved outcomes after bariatric/metabolic surgical procedures.

Ketamine as a component of multimodal analgesia for pain management in bariatric surgery: A systematic review and meta-analysis of randomized controlled trials

Introduction

Anaesthesia in morbidly obese people is challenging with a high dose of opioid consumption. This systematic review and meta-analysis of randomised controlled trials (RCTs) summaries evidence comparing ketamine to placebo for pain management after bariatric surgery.

Methods

We used PRISMA 2020 and AMSTAR 2 guidelines to conduct this study. The random-effects model was adopted using Review Manager Version 5.3 for pooled estimates.

Results

Seven RCTs published between 2009 and 2021 were eligible, including a total of 412 patients (202 patients in the ketamine group and 210 patients in the control group). In the ketamine group total opioid consumption during the first 24 h postoperatively was reduced (mean difference, MD = −5.89; 95% CI [-10.39, −1.38], p = 0.01), lower pain score at 4 h (MD = −0.81; 95% CI [-1.52, −0.10], p = 0.03), pain score at 8 h (MD = −1.00; 95% CI [-1.21, −0.79], p < 0.01), and shorter hospital stay (MD = −0.10; 95% CI [-0.20, −0.01], p = 0.03). There was no significant difference between the two groups regarding duration of anaesthesia (MD = −3.42; 95% CI [-8.62, 1.82], p = 0.20), or sedation score (MD = −0.02; 95% CI [-0.21, 0.17], p = 0.84). As concern the postoperative complications, risks of postoperative nausea and vomiting(OR = 0.75; 95% CI [0.27, 2.04], p = 0.56), hallucinations (OR = 5.47; 95% CI [0.26, 117.23], p = 0.28), dizziness (OR = 1.05; 95% CI [0.14, 7.78], p = 0.96), and euphoria (OR = 5.77; 95% CI [0.65, 51.52], p = 0.12) were not different between the two groups either.

Conclusion

Ketamine could be an effective and safe technique for pain management following bariatric surgery. It reduces opioid consumption, postoperative pain, and hospital stay.

RegistrationThis review was registered in PROSPERO (CRD42022296484).

•

This study comparing ketamine infusion or bolus with placebo when used with morphine, paracetamol or tramadol for pain management following bariatric surgery demonstrated that:

•

Ketamine was associated with lower opioid consumption during the 24 h postoperatively.

•

Ketamine decreased VAS scores at H4 and H8, and shorten the hospital stay.

•

Ketamine ensure a similar duration of anaesthesia, postoperative sedation scores, PONV, and postoperative complications rate (hallucinations, headache, euphoria and dizziness).