Effect of intravenous versus intraperitoneal magnesium sulfate on hemodynamic parameters and postoperative analgesia during laparoscopic sleeve gastrectomy-A prospective randomized study

Impact on Anesthetic Agent Consumption After Autonomic Neural Blockade as Part of a Combined Anesthesia Protocol: A Randomized Clinical Trial

BACKGROUND

The intraoperative autonomic neural blockade (ANB) was found safe and effective in controlling pain and associated symptoms and reducing analgesic consumption after laparoscopic sleeve gastrectomy (LSG). This study evaluated whether ANB performed at the outset of LSG reduces anesthetic consumption and promotes hemodynamic stability.

METHODS

This prospective, double-blinded, randomized trial involved patients undergoing LSG in 2 high-volume institutions. Patients were randomized to receive ANB either at the onset or the end of the procedure. The primary outcome measure was the consumption of remifentanil and sevoflurane. Secondary outcomes included Aldrete scale score differences in the recovery room and hemodynamic stability during the surgery.

RESULTS

In total, 80 patients (40 in the ANB at the onset group and 40 in the control group) were included for analysis. The consumption of remifentanil was significantly lower in the onset group compared to the control group (mean difference -0.04 mcg/kg/min, 95% confidence interval [CI], -0.06 to -0.02; P < .0001). There were no differences in the Aldrete scale scores between the 2 groups. Mean heart rate (HR) and mean arterial pressure (MAP) were also significantly less during surgery in the ANB at the onset group. No complications related to the ANB occurred.

CONCLUSIONS

Performing ANB at the onset of LSG is a safe and effective approach that reduces remifentanil consumption and promotes hemodynamic stability during the procedure. This technique holds promise for optimizing anesthesia management in LSG and other minimally invasive surgeries.

Effects and mechanisms of perioperative medications on the hypothalamic pituitary adrenal response to surgical injury: A narrative review

The adrenal gland is a vital endocrine organ, and adrenal steroid synthesis and secretion are closely regulated by the hypothalamic-pituitary-adrenal (HPA) axis in response to various stimuli. Surgery or trauma can activate the HPA axis and induce the secretion of cortisol. Different cortisol responses vary with the grade of surgery. Perioperative medications have the potential to decrease the cortisol level in the body, and both excessive and insufficient cortisol levels after surgery are disadvantageous. The effect of perioperative medications on the HPA response to surgery can be divided into three levels: "adrenal insufficiency (AI)", "stress response inhibition", and "uncertainty". The clinical presentation of AI includes fatigue, nausea, vomiting, abdominal pain, muscle cramps, hypotension, hypovolemic shock and prerenal failure, which may result in fatal consequences. Stress response inhibition can reduce postoperative complications, such as pain and cognitive dysfunction. This is protective to patients during perioperative and postoperative periods. The aim of the present review is to shed light on current evidence regarding the exact effects and mechanisms of perioperative medications on the HPA response to surgical injury and provide the applicable guidance on clinical anesthesia.

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.

Comparison of Two Dexmedetomidine Administration Strategies on the Incidence of Postoperative Respiratory Complications: A Retrospective, Inverse Probability of Treatment Weighted Study

Randomized controlled trials have shown a higher risk of postoperative hypoxemia and delayed extubation with opioid-free anesthesia (OFA), compared with opioid anesthesia. The practice of OFA is not standardized. The objective of this study is to investigate the association between the dexmedetomidine administration protocol used and the occurrence of postoperative respiratory complications. This work is a retrospective, propensity score-adjusted study (inverse probability of treatment weighting) conducted between January 2019 and September 2021 in a French tertiary care university hospital, including 180 adult patients undergoing major digestive surgery. Comparison of 2 anesthesia protocols: with a continuous intravenous maintenance dose of dexmedetomidine following a bolus (group B+M, n = 105) or with a bolus dose alone (group B, n = 75). The main outcome measure was a composite respiratory end point within 24 hours of surgery. There was no significant difference in the incidence of overall respiratory complications, as assessed by the primary end point. Nevertheless, there were more patients with postoperative hypercapnia in group B+M than in group B (16% vs 2.5%, P = .004). Patients in group B+M were extubated later than patients in group B (group B+M, median 40 minutes, IQR 20-74 minutes; group B, median 20 minutes, IQR 10-50 minutes; P = .004). Our study showed negative results for the primary end point. However, data on the increased risk of postoperative hypercapnia in patients receiving a maintenance dose of dexmedetomidine are new. Other prospective randomized studies with greater power are necessary to confirm these data and to make OFA safer, by reducing the prescribed doses of dexmedetomidine.

Analgesic Efficacy and Outcomes of Ultrasound-guided Erector Spinae Plane Block in Patients Undergoing Bariatric and Metabolic Surgeries: A Systematic Review

Erector spinae plane block (ESPB) has been used as an intervention for providing postoperative analgesia in patients undergoing bariatric and metabolic surgeries. After registering the protocol in PROSPERO, randomized controlled trials and nonrandomized observational studies were searched in various databases till July 2022. The primary outcome was 24-h opioid consumption; the secondary outcomes were intraoperative opioid use, pain scores, time to rescue analgesia, and complications. The risk of bias and Newcastle-Ottawa scale were used to assess the quality of evidence. From the 695 studies identified, 6 studies were selected for analysis. The 24-h opioid consumption was significantly lesser in ESPB group when compared to control (mean difference [MD]: -10.67; 95% confidence interval [CI]: -21.03, -0.31, I² = 99%). The intraoperative opioid consumption was significantly less in the ESPB group (MD: -17.75; 95% CI: -20.36, -15.13, I² = 31%). The time to rescue analgesia was significantly more in the ESPB group (MD: 114.36; CI: 90.42, 138.30, I² = 99%). Although pain scores were significantly less at 6 and 24 h in ESPB group (MD: -2.00, 95% CI: -2.49, -1.51; I² = 0% and MD: -0.48; 95% CI: -0.72, -0.24; I² = 48%), at zero and 12 h, the pain scores were comparable (MD: -1.53, 95% CI: -3.06, -0.00, I² = 97% and MD: -0.80; 95% CI: -1.80, 0.20, I² = 88%). Bilateral ESPB provides opioid-sparing analgesia and better pain scores when compared to control. These results should be interpreted with caution due to high heterogeneity among the included studies.

Effect of magnesium sulfate with ketamine infusions on intraoperative and postoperative analgesia in cancer breast surgeries: a randomized double-blind trial

BACKGROUND

Opioids are the cornerstone in managing postoperative pain; however, they have many side effects. Ketamine and Magnesium (Mg) are NMDA receptor antagonists used as adjuvant analgesics to decrease postoperative opioid consumption.

OBJECTIVE

We assumed that adding Mg to ketamine infusion can improve the intraoperative and postoperative analgesic efficacy of ketamine infusion alone in cancer breast surgeries.

METHODS

Ninety patients aged between 18 and 65 years and undergoing elective cancer breast surgery were included in this prospective randomized, double-blind study. Group K received ketamine 0.5.ßmg.kg^...1 bolus then 0.12.ßmg.kg^...1.h^...1 infusion for the first 24.ßhours postoperatively. Group KM: received ketamine 0.5.ßmg.kg^...1 and Mg sulfate 50.ßmg.kg^...1, then ketamine 0.12.ßmg.kg^...1.h^...1 and Mg sulfate 8.ßmg.kg^...1.h^...1 infusions for the first 24.ßhours postoperative. The primary outcome was the morphine consumption in the first 24.ßhours postoperative, while the secondary outcomes were: intraoperative fentanyl consumption, NRS, side effects, and chronic postoperative pain.

RESULTS

Group KM had less postoperative opioid consumption (14.12.ß...ß5.11.ßmg) than Group K (19.43.ß...ß6.8.ßmg). Also, Group KM had less intraoperative fentanyl consumption. Both groups were similar in postoperative NRS scores, the incidence of side effects related to opioids, and chronic neuropathic pain.

CONCLUSION

Adding Mg to ketamine infusion can safely improve intraoperative and postoperative analgesia with opioid-sparing effect in cancer breast surgery.

Paragastric Autonomic Neural Blockade to Prevent Early Visceral Pain and Associated Symptoms After Laparoscopic Sleeve Gastrectomy: a Randomized Clinical Trial

Background

Visceral pain (VP) following laparoscopic sleeve gastrectomy remains a substantial problem. VP is associated with autonomic symptoms, especially nausea and vomiting, and is unresponsive to traditional pain management algorithms aimed at alleviating somatic (incisional) pain. The present study was performed to evaluate the safety and effectiveness of laparoscopic paragastric autonomic neural blockade (PG-ANB) in managing the symptoms associated with VP following sleeve gastrectomy.

Study Design

This prospective, double-blinded, randomized clinical trial involved patients undergoing laparoscopic sleeve gastrectomy at two high-volume institutions. The patients were randomized to laparoscopic transversus abdominis plane block with or without PG-ANB. The primary outcome was patient-reported pain scores assessed at 1, 8, and 24 h postoperatively. The secondary outcome measures were analgesic requirements, nausea, vomiting, hiccups, and hemodynamic changes immediately after PG-ANB and postoperatively.

Results

In total, 145 patients (block group, n = 72; control group, n = 73) were included in the study. The heart rate and mean arterial pressure significantly decreased 10 min after PG-ANB. The visual analog scale score for pain was significantly lower in the PG-ANB than in the control group at 1 h postoperatively (p < 0.001) and 8 h postoperatively (p < 0.001). Vomiting, nausea, sialorrhea, and hiccups were significantly less prevalent in the PG-ANB group. Patients in the PG-ANB group received fewer cumulative doses of analgesics at 1 h postoperatively (p = 0.003) and 8 h postoperatively (p < 0.001). No differences between the groups were detected at 24 h (p = 0.298). No complications related to PG-ANB occurred.

Conclusion

PG-ANB safely and effectively reduces early VP, associated autonomic symptoms, and analgesic requirements after laparoscopic sleeve gastrectomy.

Graphical abstract

Enhanced recovery after bariatric surgery: an Italian consensus statement

Background

Enhanced recovery after bariatric surgery (ERABS) is an approach developed to improve outcomes in obese surgical patients. Unfortunately, it is not evenly implemented in Italy. The Italian Society for the Surgery of Obesity and Metabolic Diseases and the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care joined in drafting an official statement on ERABS.

Methods

To assess the effectiveness and safety of ERABS and to develop evidence-based recommendations with regard to pre-, intra-, and post-operative care for obese patients undergoing ERABS, a 13-member expert task force of surgeons and anesthesiologists from Italian certified IFSO center of excellence in bariatric surgery was established and a review of English-language papers conducted. Oxford 2011 Levels of Evidence and U.S. Preventive Services Task Force Grade Definitions were used to grade the level of evidence and the strength of recommendations, respectively. The supporting evidence and recommendations were reviewed and discussed by the entire group at meetings to achieve a final consensus.

Results

Compared to the conventional approach, ERABS reduces the length of hospital stay and does not heighten the risk of major post-operative complications, re-operations, and hospital re-admissions, nor does it increase the overall surgical costs. A total of 25 recommendations were proposed, covering pre-operative evaluation and care (7 items), intra-operative management (1 item, 11 sub-items), and post-operative care and discharge (6 items).

Conclusions

ERABS is an effective and safe approach. The recommendations allow the proper management of obese patients undergoing ERABS for a better outcome.

Analgesic and hemodynamic effects of intravenous infusion of magnesium sulphate versus dexmedetomidine in patients undergoing bilateral inguinal hernial surgeries under spinal anesthesia: a randomized controlled study

BACKGROUND

Spinal anesthesia is commonly employed during inguinal hernial surgeries. Its short duration may, however, be considered a limitation, especially for bilateral hernial repair. The aim of this research is to investigate the analgesic and hemodynamic effects of intravenous infusion of both MgSO₄ and dexmedetomidine on patients undergoing bilateral inguinal hernia surgeries under spinal anesthesia.

METHODS

This study was a prospective, randomized, double-blinded controlled trail. It included 60 male patients who had been scheduled for bilateral elective inguinal hernia surgery under spinal anesthesia at Kasr Al-Aini hospital. Patients were randomly allocated to one of three groups (n = 20 each) to receive 50 mL of 0.9% saline intravenous infusion of either dexmedetomidine 0.5 μg.kg^-1. h^-1 (Group D) or magnesium sulphate 15 mg.kg^-1. h^-1 (Group M) or normal saline (Group S). The primary outcome of this study was set as the total duration of analgesia. Secondary outcomes were set as the onset and duration of sensory and motor blockade, perioperative hemodynamics, and the total 24-hour postoperative morphine consumption.

RESULTS

Durations of sensory and motor blockades as well as durations of analgesia were all significantly longer among patients in Group D (mean 2.2, 3.5, 5.8 hours respectively) and Group M (mean 2.2, 3.3, 5.2 hours respectively), in comparison to Group S (mean 1.5, 2.7, 3.9 hours respectively). No significant differences were found in systolic or diastolic arterial blood pressure, heart rate oxygen saturation, cardiac output, or stroke volume among the study groups. Seven patients in Group D and four patients in Groups M and S developed hypotension.

CONCLUSION

Intravenous infusion of either dexmedetomidine or MgSO₄ with spinal anesthesia effectively improves the quality of spinal anesthesia and prolongs the duration of postoperative analgesia and decreases the 24-hour postoperative morphine consumption. Results also demonstrated that the use of dexmedetomidine resulted in a slightly longer duration of analgesia, whilst the use of MgSO₄ resulted in slightly better hemodynamic stability.

Comparison of three intraoperative analgesic strategies in laparoscopic bariatric surgery: a retrospective study of immediate postoperative outcomes

Introduction and objectives

Multimodal Analgesia (MMA) has shown promising results in postoperative outcomes across a broad spectrum of surgeries, including bariatric surgery. We compared the analgesic effect immediately after Laparoscopic Bariatric Surgery (LBS) of the combined effect of MMA and methadone against two techniques that were based mainly on the use of high-potency medium-acting opioids.

Methods

Two hundred seventy-one patients were retrospectively reviewed. The primary outcome was postoperative pain score > 3/10 measured by the Verbal Numeric Scale (VNS) during the Postanesthetic Care Unit (PACU) stay. The three protocols of intraoperative analgesia were: (P1) sufentanil at anesthetic induction followed by remifentanil infusion; (P2) sufentanil at induction followed by dexmedetomidine infusion; and (P3) remifentanil at induction followed by MMA including dexmedetomidine, magnesium, lidocaine, and methadone. Only P1 and P2 patients received morphine toward the end of surgery. Poisson regression was used to adjust confounding factors and calculate Prevalence Ratio (PR).

Results

Postoperative VNS > 3 was recorded in 135 (49.81%) patients, of which 93 (68.89%) were subjected to P1, 25 (18.56%) to P2, and 17 (12.59%) to P3. In the final adjusted model, both anesthetic techniques (P3) (PR = 0.10; 95% CI [0.03–0.28]), and (P2) (PR = 0.42%; 95% CI [0.20–0.90]) were associated with lower occurrence of VNS > 3, whereas age range 20–29 was associated to higher occurrence of VNS > 3 (PR = 3.21; 95% CI [1.22–8.44]) in PACU. Postoperative Nausea and Vomiting (PONV) was distributed as follows: (P1) 20.3%, (P2) 31.25% and (P3) 6.77%; (P3 < P1, P2; p < 0.05). Intraoperative hypotension occurred more often in P3 (39%) compared to P2 (20.31%) and P1 (17.46%) (p < 0.05).

Conclusion

MMA + methadone was associated with higher incidence of intraoperative hypotension and lower incidence of moderate/severe pain in PACU after LBS.

Beneficial Effects of Intravenous Magnesium Administration During Robotic Radical Prostatectomy: A Randomized Controlled Trial

INTRODUCTION

Robotic radical prostatectomy requires prolonged pneumoperitoneum and a steep Trendelenburg position. Magnesium can attenuate the stress response and hemodynamic perturbations. This study aimed to evaluate the effects of intravenous magnesium administration on hemodynamics and the stress response in patients undergoing robotic radical prostatectomy.

METHODS

In this prospective, double-blind, randomized controlled study, 52 patients undergoing robotic radical prostatectomy were randomized into two groups: 26 in the magnesium group and 26 in the control group. The patients in the magnesium group received magnesium sulfate 50 mg/kg intravenously, followed by infusion at a rate of 10 mg/kg/h during surgery. The patients in the control group received an equal volume of 0.9% saline. The primary outcomes were the changes in heart rate and mean arterial pressure (MAP) during surgery. The serum stress hormones (adrenocorticotropic hormone, cortisol, epinephrine, and norepinephrine) were also measured.

RESULTS

MAP showed a significant intergroup difference over time (P_group*time = 0.017); it increased significantly at 5 min after Trendelenburg position in the control group and decreased significantly at 30 min after Trendelenburg position in the magnesium group. The intergroup difference in the change in cortisol concentrations was significant over time (P_group*time = 0.006). The cortisol concentration decreased significantly from baseline to 24 h after surgery in the magnesium group but did not change significantly in the control group. The requirement for intraoperative remifentanil was 35% lower in the magnesium group (P = 0.011), and the severity of postoperative pain at 30 min and 6 h after surgery was also lower in the magnesium group (P = 0.024 and P = 0.015).

CONCLUSION

There is a possibility that intravenous magnesium administration during robotic radical prostatectomy reduces the increases in arterial pressure, cortisol concentrations, opioid requirements, and postoperative pain.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02833038.

Magnesium and Pain

In terms of antinociceptive action, the main mode of action of magnesium involves its antagonist action at the N-methyl-d-aspartate (NMDA) receptor, which prevents central sensitization and attenuates preexisting pain hypersensitivity. Given the pivotal function of NMDA receptors in pain transduction, magnesium has been investigated in a variety of pain conditions. The oral and parenteral administration of magnesium via the intravenous, intrathecal, or epidural route may alleviate pain and perioperative anesthetic and analgesic requirements. These beneficial effects of magnesium therapy have also been reported in patients with neuropathic pain, such as malignancy-related neurologic symptoms, diabetic neuropathy, postherpetic neuralgia, and chemotherapy-induced peripheral neuropathy. In addition, magnesium treatment is reportedly able to alleviate fibromyalgia, dysmenorrhea, headaches, and acute migraine attacks. Although magnesium plays an evolving role in pain management, better understanding of the mechanism underlying its antinociceptive action and additional clinical studies is required to clarify its role as an adjuvant analgesic.

A Practical Approach to Acute Postoperative Pain Management in Chronic Pain Patients

In the United States, more than 100 million people suffer from chronic pain. Among patients presenting for surgery, about one in four have chronic pain. Acute perioperative pain management in this population is challenging because many patients with chronic pain require long-term opioids for the management of this pain, which may result in tolerance, physical dependence, addiction, and opioid-induced hyperalgesia. These challenges are compounded by the ongoing opioid epidemic that has resulted in calls for a reduction in opioid use, with a concurrent increase in the number of patients with chronic opioid exposure presenting for surgery. This article aims to summarize practical considerations for acute postoperative pain management in patients with chronic pain conditions. A patient-centered acute pain management plan, including nonopioid analgesics, regional anesthesia, and careful selection of opioid medications, can lead to adequate analgesia and satisfaction with care. Also, a meticulous rotation from one opioid to another may decrease opioid requirement, increase analgesic effectiveness, and improve satisfaction with care.

The Impact of Perioperative Use of a Statin-Magnesium Combination on Opioid Consumption in Patients Who Underwent Cardiac Surgery: A Retrospective Study with Propensity-Score Matching

Both statins and magnesium are associated with NMDA receptors and anti-inflammatory effect. Peripheral NMDA receptors are known to be involved in inflammation-induced pain. This study aimed to investigate the impact of perioperative use of a statin–magnesium combination on opioid consumption in patients who underwent cardiac surgery. This was a retrospective study of 542 patients who underwent cardiac surgery. The patients were divided into two groups according to statin use: the statin–magnesium group (n=375) and the magnesium-only group (n=167). Patients in the magnesium-only group received only perioperative magnesium, but no statins, to prevent atrial fibrillation following cardiac surgery. After propensity-score matching, 228 patients (n=114 in each group) were analyzed to investigate opioid consumption, visual analogue scale (VAS) pain scores over a 72-h period, and pain outcomes according to the duration of statin treatment (<1 or ≥1 yr). The consumed opioid volume was significantly smaller in statin–magnesium group than the magnesium-only group, both before (p=0.010) and after matching (p=0.017). The statin–magnesium combination did not significantly reduce the VAS pain scores compared with magnesium alone. Although the statin–magnesium combination did not significantly reduce the pain intensity compared with magnesium alone, the combination therapy was effective in reducing opioid consumption after surgery.

Perioperative care of the obese patient

Background

Obesity has become an increasing problem worldwide during the past few decades. Hence, surgeons and anaesthetists will care for an increasing number of obese patients in the foreseeable future, and should be prepared to provide optimal management for these individuals. This review provides an update of recent evidence regarding perioperative strategies for obese patients.

Methods

A search for papers on the perioperative care of obese patients (English language only) was performed in July 2019 using the PubMed, Scopus, Web of Science and Cochrane Library electronic databases. The review focused on the results of RCTs, although observational studies, meta-analyses, reviews, guidelines and other reports discussing the perioperative care of obese patients were also considered. When data from obese patients were not available, relevant data from non-obese populations were used.

Results and conclusion

Obese patients require comprehensive preoperative evaluation. Experienced medical teams, appropriate equipment and monitoring, careful anaesthetic management, and an adequate perioperative ventilation strategy may improve postoperative outcomes. Additional perioperative precautions are necessary in patients with severe morbid obesity, metabolic syndrome, untreated or severe obstructive sleep apnoea syndrome, or obesity hypoventilation syndrome; patients receiving home ventilatory support or postoperative opioid therapy; and obese patients undergoing open operations, long procedures or revisional surgery.