The effect of magnesium sulfate on motor and sensory axillary plexus blockade

The effect of adjuvants added to local anaesthetics for single-injection upper extremity peripheral regional anaesthesia: A systematic review with network meta-analysis of randomised trials

BACKGROUND

Peripheral regional anaesthesia is frequently used for upper extremity surgery. To prolong the duration of analgesia, adjuvants can be added to single-injection local anaesthetics. Despite attempts to compare several adjuvants in pairwise meta-analyses, a comprehensive comparison is still missing.

OBJECTIVE

The objective of this network meta-analysis was to determine the effectiveness of adjuvants in upper extremity peripheral nerve blocks.

DESIGN

A systematic review of randomised controlled trials with network meta-analyses.

DATA SOURCES

A literature search in Embase, CENTRAL, MEDLINE and Web of Science was performed up to March 2023.

ELIGIBILITY CRITERIA

Randomised trials comparing different adjuvants injected perineurally in peripheral upper extremity nerve blocks were eligible. Frequentist network meta-analysis was conducted using a random effects model with physiological saline as the comparator. The primary endpoint was the ratio of means (ROM) of the duration of analgesia.

RESULTS

The review included 242 randomised controlled trials with a total of 17 391 patients. Twenty-eight adjuvants were compared in the largest networks. Most network estimations consisted of a high proportion of direct evidence. Fourteen adjuvants increased the duration of analgesia significantly by the following factors, ROM [95% confidence interval (CI)]: dexamethasone 1.95 (1.79 to 2.13), buprenorphine 1.83 (1.51 to 2.24), butorphanol 1.84 (1.41 to 2.39), potassium chloride 1.89 (1.15 to 3.11), dexmedetomidine 1.70 (1.59 to 1.81), sufentanil 1.70 (1.27 to 2.29), ketorolac 1.68 (1.24 to 2.27), midazolam 1.55 (1.24 to 1.94), tramadol 1.52 (1.32 to 1.75), nalbuphine 1.50 (1.30 to 1.72), morphine 1.43 (1.09 to 1.88), magnesium sulfate 1.42 (1.20 to 1.67), clonidine 1.36 (1.24 to 1.50) and fentanyl 1.23 (1.08 to 1.40). Inconsistency in network meta-analysis was substantial. Overall side effect rates were low with all adjuvants.

CONCLUSION

The best interventions to prolong the duration of analgesia were dexamethasone, followed by dexmedetomidine, opioids, electrolytes, ketorolac and midazolam. There are general concerns about the quality of underlying studies and the risk of publication bias.

TRIAL REGISTRATION

PROSPERO 2018 CRD42018115722.

The Use of Magnesium Sulfate and Peripheral Nerve Blocks: An Updated Meta-analysis and Systematic Review

OBJECTIVES

With the popularization of ultrasound, nerve blocks have been widely implemented in current clinical practice. Although, they have seen limited success due to their shorter duration and suboptimal analgesia. Magnesium sulfate as a local anesthetic adjuvant for peripheral nerve blocks could enhance the effects of local anesthetics. However, previous investigations have not thoroughly investigated the analgesic efficacy of magnesium sulfate as an adjunct to local anesthetics for peripheral nerve blocks. Thus, we attempted to fill the gap in the existing literature by conducting a meta-analysis.

MATERIALS AND METHODS

We performed of a quantitative systematic review of randomized controlled trials published between May 30, 2011 and November 1, 2018. Inclusion criteria were: (1) magnesium sulfate used as adjuvant mixed with local anesthetic for nerve blockade, (2) complete articles and published abstracts of randomized controlled trials, (3) English language.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measures were time of onset, total duration of the sensory blockade, and Visual Analog Scale pain scores. The secondary outcomes were postoperative oral and intravenous analgesics consumption and the incidence of nausea and vomiting.

RESULTS

The 21 trials analyzed in this study included 1323 patients. Magnesium sulfate effectively prolonged the total duration of sensory blockade (mean difference [MD]=114.59 min, 95% confidence interval [CI]: 89.31-139.88), reducing Visual Analog Scale pain scores at 6 hours (MD=1.36 points, 95% CI: -2.09 to -0.63) and 12 hours (MD=1.54 points, 95% CI: -2.56 to -0.53) postsurgery. Magnesium sulfate also effectively reduced postoperative analgesic use within 24 hours postsurgery (standard MD=-2.06, 95% CI: -2.67 to -1.35). Furthermore, adjuvant magnesium sulfate significantly reduced the incidence of nausea and vomiting after transversus abdominis plane blockade (odds ratio: 0.39, 95% CI: 0.18-0.81).

CONCLUSION

Adjuvant magnesium sulfate enhanced the anesthetic effects of local anesthetics and improved postoperative analgesia following the perineural blockade.

The Effects of Magnesium Sulfate with Lidocaine for Infraclavicular Brachial Plexus Block for Upper Extremity Surgeries

Background  An addition of analgesic to anesthetic agents is likely to increase the effects of anesthesia and reduce associated adverse outcomes. Several adjuvants are studied in this regard. The aim of this study is to investigate the effects of adding a magnesium adjunct to lidocaine for the induction of infraclavicular block. Methods  Patients referred to Shohada Ashayer Hospital, Khorramabad, for wrist and hand surgery were enrolled in this study. The intervention/case group included patients who received 18 mL lidocaine (2%) + 2 mL magnesium sulfate (50%), 10 mL normal saline; control group: 18 mL lidocaine (2%) + 12 mL of normal saline. After the induction of ultrasound-guided infraclavicular block, parameters such as duration of reach with respect to complete sensory and motor block, hemodynamic parameters (hypotension and bradycardia), and postoperative pain, using visual analogue scale criteria, were measured. The obtained data were analyzed using a Bayesian path analysis model. Results  A total of 30 patients were included in each group. In the case group, sensory and motor block was achieved for 12.136 ± 4.96 and 13 ± 3.589 minutes more than those in the control group. The duration of sedation and immobilization was 2.57 ± 0.764 minute and 4.66 ± 0.909 minutes lengthier in the case group. Regarding the hemodynamic parameters, blood pressure was 0.217 ± 5.031 and 1.59 ± 5.14 units lower in the case group, immediately following the block and the surgery. Similarly, heart rate was 0.776 ± 4.548 and 0.39 ± 3.987 units higher in the case group, after 30 minutes and 2 hours of the procedure. A decrease in the pain was seen at 8, 10, and 12 hours after the surgery, as compared with the control group. An addition of magnesium to lidocaine for infraclavicular block resulted in a significantly longer sedation and immobilization period and decreased postoperative pain at 12 hours. Conclusion  Heart rate and blood pressure did not decrease significantly in the case group. It can be concluded that addition of magnesium sulfate to lidocaine can produce better anesthetic and analgesic outcomes with low-to-no adverse effects.

Comparison of Magnesium Sulfate and Ketamine with Ropivacaine in Supraclavicular Brachial Plexus Block: A Randomized Controlled Trial

Background:

Supraclavicular brachial plexus block offers good operating conditions with limited postoperative analgesia. Magnesium sulfate (MgSO₄) and ketamine block peripheral nociception mediated via N-methyl-D-aspartate receptors.

Aims:

The aim of this study was to evaluate the effect of MgSO₄ and ketamine on the duration of analgesia in brachial block.

Settings and Design:

This was a prospective, randomized, controlled double-blind study.

Materials and Methods:

One hundred and five adult patients were randomly divided into three groups: Group I = 27 mL of 0.5% ropivacaine; Group II = 27 mL of 0.5% ropivacaine + 250 mg MgSO₄; and Group II = 27 mL of 0.5% ropivacaine + 2 mg.kg⁻¹ ketamine. Normal saline was added to make a total volume of 30 mL. The onset and duration of the sensorimotor blockade, quality and duration of postoperative analgesia, and adverse effects were assessed.

Statistical Analysis:

Statistical analysis was performed using SPSS, version 17.0 software (SPSS, Inc., Chicago, IL, USA). Chi-square test was used for nonparametric and ANOVA for parametric data. Post hoc Student's paired t-test was applied wherever indicated. The results were expressed as mean and standard deviation or numbers (%). P < 0.05 was considered as statistically significant.

Results:

The duration of analgesia was significantly longer in Group II (8.78 ± 0.97 h) compared to Group I (6.76 ± 0.92 h; P < 0.001) and Group III (7.1 ± 0.89 h; P < 0.001). Intervention groups had lower postoperative visual analog scores at 8, 12, and 24 h compared to the control group. Sedation, nystagmus, and hallucinations were observed in Group III.

Conclusion:

The addition of MgSO₄ to ropivacaine in supraclavicular brachial plexus block significantly prolongs the duration of analgesia. MgSO₄ improves the quality of postoperative analgesia with lesser incidence of side effects when compared to ketamine.

The use of intravenous magnesium sulfate on postoperative analgesia in orthopedic surgery: A systematic review of randomized controlled trials

INTRODUCTION

The aim of this systematic review is to investigate the effects of perioperative intravenous administration of MgSO4 on postoperative pain, analgesic consumption and adverse effects in patients undergoing orthopedic surgery.

METHODS

Two investigators independently searched for articles on randomized controlled trials (RCTs) from 1998 to 2016 in Pubmed, Web of science and Google scholar. We evaluated clinical outcomes, comparing postoperative pain scores, cumulative analgesic consumption, time to first analgesia, and adverse effects between orthopedic surgery patients with and without the administration of MgSO4.

RESULTS

After screening 2350 articles, 11 RCTs (with a total sample size of 535 subjects) were included in this systematic review. Perioperative intravenous administered MgSO4 could reduce postoperative pain intensity compared with control in 6 trials (55%), but without significant difference in 5 trials (45%). With MgSO4 treatments, postoperative analgesic consumption was significantly reduced in 8 trials (73%), and without significant difference in 2 trials (18%). Two trials evaluated the time to first request of analgesic after surgery and showed prolong of 2.3 hours and 93 minutes respectively. MgSO4 group had less postoperative nausea (relative risk [RR] = 0.32, 95% confidence interval [CI] = 0.12-0.82, number needed to harm [NNH] = 8.8), vomiting (RR = 0.38, 95% CI = 0.15-0.92, NNH = 9.7), and shivering (RR = 0.31, 95% CI = 0.11-0.88, NNH = 5.2).

CONCLUSION

Perioperative intravenous administration of MgSO4 in orthopedic surgery could reduce postoperative analgesic consumption and adverse effects such as vomiting, nausea, and shivering. These trials do not provide convincing evidence of beneficial effects on postoperative pain intensity and the time to first analgesic request. More trials should be conducted for the roles of MgSO4 in pain management for orthopedic surgery. However, intravenous MgSO4 administration should be considered as a strategy to relieve postoperative pain in orthopedic surgery patients.

Does Adding Lidocaine to Intrathecal Bupivacaine Affect Hemodynamic Parameters during Hip Fracture Surgery?

BACKGROUND

Hip fracture is one of the most common problems in elderly that needs surgical repair. As, the majority of these patients have chronic diseases, they are at increased risk of peri-operative mortality and morbidity. The purpose of this study was to evaluate spinal anesthesia with bupivacaine vs bupivacaine in combination with lidocaine in terms of hemodynamic changes in patients undergoing hip fracture surgery.

METHODS

This double-blind clinical trial was conducted on 292 patients undergoing surgery for hip fracture under spinal anesthesia. Patients were allocated into two groups of B (10 mg of hyperbaric 0.5% Bupivacaine) and BL (5 mg hyperbaric Bupivacaine 0.5% plus 50 mg Lidocaine 5%). Sensory and motor block and hemodynamic changes were consecutively measured before spinal anesthesia (T0), immediately after spinal injection (T1), every 5 minutes for half an hour (T2- T7), and at 45 minutes (T8) and 60 minutes (T9) after injection.

RESULTS

Patients in the two groups were homogeneous in demographic characteristics including age, sex, BMI, ASA Class, baseline blood pressure and heart rate. The onsets of sensory and motor blocks in group BL were faster than group B (P=0.0001). Also, the durations of sensory and motor blocks in group B were significantly longer than group BL (P=0.0001). The BL group had a significantly lower systolic blood pressure in all periods (P<0.05). Although the heart rate in the BL group was lower than group B at all time points, this difference was only significant during T2-T3 (P=0.033 and P=0.0001, respectively). Group BL had significantly more episodes of hypotension, bradycardia, nausea and vomiting (P=0.0001, P=0.023, P=0.003, and P=0.033, respectively).

CONCLUSION

According to our findings, using Lidocaine 50 mg in combination with Bupivacaine 5 mg, compared with Bupivacaine 10 mg alone for spinal anesthesia in hip fracture fixation surgeries was associated with more hypotension and bradycardia. As a result, combination of Bupivacaine with Lidocaine at this dose is not recommended for induction of anesthesia in these patients.

An Evaluation of the Adding Magnesium Sulfate to Ropivacaine on Ultrasound-Guided Transverse Abdominis Plane Block After Abdominal Hysterectomy

Background

Post-hysterectomy pain is extremely annoying and using transverse abdominis plane (TAP) block can be a useful method to manage postoperative pain, but its duration of effect is challenging. Magnesium sulfate increases, in some cases, the effects of local anesthetics on the peripheral nerve blocks.

Objectives

The current study aimed at investigating the effects of adding magnesium sulfate to ropivacaine in the transverse abdominis plane block after hysterectomy.

Methods

The current randomized, double blind, clinical trial, to manage postoperative pain, was conducted on a total of 60 patients, 30 - 60 years old, ASA (American Society of Anesthesiologists) class I-II undergone elective abdominal hysterectomy candidates to receive ultrasound-guided bilateral transverse abdominis abdominis plane (TAP) blocks. Patients with coagulation disorders, infection, history of any addiction, sensitivity to the local anesthetics and magnesium sulfate were excluded. The subjects were equally allocated into two groups, the control group, ropivacaine plus normal saline (R), and the study group, ropivacaine plus magnesium sulfate (RM). The injection contained 19 mL ropivacaine 0.2% plus 1 mL normal saline in the group R, and 19 mL ropivacaine 0.2% plus 1 mL magnesium sulfate 50% in the RM group on each side. As well as the patients' characteristics, the level of pain score (visual analogue scale = VAS), rescue analgesic demand (diclofenac suppository), and possible adverse effects were evaluated at 1, 2, 6, 12, and 24 hours after the operation in the two groups.

Results

The mean pain scores of the patients at the first hour after surgery were 5.7 ± 0.9 and 5.9 ± 1.1 in R and RM groups, respectively. The scores reached 2.9 ± 0.5 and 2.7 ± 0.4 at the second hour after surgery (the first post-block measurement) and 3.1 ± 0.7 and 2.8 ± 0.7 within the next 24 hours, respectively. Although the pain scores were generally lower at all hours in the RM group, none was statistically significant. The rescue analgesic consumption gradually increased in the two groups, and it was less in the study group than in the control group in the first hours after the block (second hour after surgery); however, it was not statistically significant. No adverse effects were observed in the two groups.

Conclusions

Results of the current study suggested that the addition of magnesium sulfate to ropivacaine in TAP block does not affect the post-hysterectomy pain.

Comparison of Magnesium Sulfate and Dexmedetomidine as an Adjuvant to 0.5% Ropivacaine in Infraclavicular Brachial Plexus Block

Background:

Magnesium sulfate and dexmedetomidine were used as adjuvants to local anesthesia to improve the quality of regional anesthesia.

Aims:

The aim of this study is to evaluate and compare the effects of magnesium sulfate and dexmedetomidine when added to ropivacaine on the quality of infraclavicular brachial plexus block (BPB).

Settings and Design:

This was a prospective randomized double-blinded controlled study.

Patients and Methods:

A total of 105 adult patients undergoing surgery in hands, wrist, and forearm using infraclavicular BPB were randomly assigned into three groups. Ultrasound-guided infraclavicular BPB was performed using 35 ml ropivacaine 0.5% diluted with 4 ml normal saline 0.9%. Magnesium sulfate 150 mg and dexmedetomidine 100 μg were added in the magnesium sulfate group and dexmedetomidine group, respectively. Duration of analgesia, onset times and durations of sensory block (SB) and motor block (MB), patient's satisfaction, and complications were recorded.

Statistical Analysis:

Statistical software SPSS 16 was used for statistical analysis.

Results:

Dexmedetomidine and magnesium sulfate provided longer duration of analgesia and lesser consumption of postoperative rescue analgesia than the control group (P = 0. 000); dexmedetomidine provided the longest duration of analgesia versus control and magnesium sulfate groups (P = 0.000). Dexmedetomidine provided the quickest onset times and the longest durations of both SB and MB than control and magnesium sulfate groups (P = 0.000). Dexmedetomidine group had higher incidences of bradycardia and hypotension.

Conclusions:

Magnesium sulfate or dexmedetomidine is a useful adjuvant to ropivacaine for infraclavicular BPB in lengthening the duration of analgesia. Dexmedetomidine provided quicker onset and longer duration of both SB and MB and longer duration of analgesia with lesser consumption of postoperative rescue analgesia; however, it showed a higher incidence of intraoperative hypotension and bradycardia than magnesium sulfate.

A Comparison between Single and Double Tourniquet Technique in Distal Upper Limb Orthopedic Surgeries with Intravenous Regional Anesthesia

BACKGROUND

Several studies have put an effort to minimize the tourniquet pain and complications after conventional double tourniquet intravenous regional anesthesia (IVRA). We expressed in our hypothesis that an upper arm single wide tourniquet (ST) may serve a better clinical efficacy rather than the conventional upper arm double tourniquet (DT) in distal upper extremity surgeries.

METHODS

In this randomized controlled trial, 80 patients undergoing upper limb orthopedic surgeries were randomized into two groups. IVRA was administered using lidocaine in both groups. Tourniquet pain was recorded based on visual analogue scale (VAS). In case of pain (VAS>3) in the DT group, the proximal tourniquet was replaced with a distal tourniquet while fentanyl 50µg was injected in the ST group. The onset time of tourniquet pain, time to reach to maximum tourniquet pain and the amount of fentanyl consumption were compared between the two groups.

RESULTS

No significant difference was seen in demographic characteristics. The onset time of tourniquet pain (VAS=1) in the ST group (26.9±13.2 min) was longer than that of the DT group (13.8±4.8 min) (P<0.0001). The median of time to reach to maximum tourniquet pain (VAS>3) in DT and ST groups were 25 and 40 minutes, respectively; indicating that the patients in ST group reached to pain level at a significantly later time (P<0.0001). The total opioid consumption in the DT group (61 µg) was significantly lower than the ST group (102 µg) (P<0.0001); however, both groups were similar regarding fentanyl consumption before 40 minutes of surgeries.

CONCLUSION

It seems that in upper limb orthopedic surgeries with less than 40-minute duration, a single tourniquet may serve as a proper alternative opposed to the conventional double tourniquet technique.Level of evidence: II.

The Effect of Intravenous Magnesium Sulfate Versus Intravenous Sufentanil on the Duration of Analgesia and Postoperative Pain in Patients with Tibia Fracture

BACKGROUND

In the recent decades controlling postoperative pain has become a popular topic as it leads to the patients' wellbeing and improved life quality, while it reduces the costs for both patients and medical facilities.

OBJECTIVES

This study aimed at comparing intravenous magnesium sulfate versus intravenous sufentanil on the duration of analgesia and postoperative pain in patients undergoing tibia fracture surgery.

METHODS

This double blind clinical trial study was performed on 70 candidates of tibia fractures between the ages of 18 and 55 years with American society of anesthesiologists (ASA) class I and II. The patients were randomly divided to 2 groups, 1 receiving magnesium sulfate (M) and another receiving sufentanil (S). Both of the groups underwent spinal anesthesia with 10 mg bupivacaine 0.5%. One hour after ensuring the sensorimotor blockade, in the S group 0.1 µg/kg/hour and in the M group 8 mg/kg/hour was diluted in 1 liter of Ringer's solution and infused. In this study, full weakness of the lower limb was considered as the sign of sensorimotor blockade initiation. The postoperative pain intensity was measured using the Visual Analog Scale (VAS), 0, 1, 4, 8, 16, and 24 hours after the end of anesthesia duration. In case of VAS ≥ 3, the patients received 0.3 mg/kg pethidine, intravenously. At last, the time of requesting the first narcotic drug and the total usage of pethidine were recorded.

RESULTS AND CONCLUSIONS

Sufentanil was found to be more effective than magnesium sulfate in reducing postoperative pain and the time of first narcotics request was later in patients receiving sufentanil (P < 0.05).

The Effect of Magnesium Sulfate on Postoperative Pain in Upper Limb Surgeries by Supraclavicular Block Under Ultrasound Guidance

BACKGROUND

Previous studies have been conducted to evaluate the effect of different adjuvants on brachial plexus block.

OBJECTIVES

This study investigated the effect of adding magnesium sulfate to lidocaine on postoperative pain in upper limb surgeries by supraclavicular brachial plexus block under ultrasound guidance.

METHODS

This study was carried out on patients who were candidate for upper limb surgeries. This was a controlled double-blind study conducted on a number of 52 patients aged 18 - 75 years with ASA class I or II. The first group (M) received lidocaine 1% (4 mg/kg) plus fentanyl 50 micg and magnesium sulfate 20% (5 mL) while the second group (N) received lidocaine 1% (4 mg/kg) plus fentanyl 50 micg and normal saline (5 mL) to supraclavicular brachial plexus block under ultrasound guidance. Postoperative pain was evaluated by visual analog scale (VAS) until 24 hours. Sensory and motor blocks onset and duration, rescue analgesics, hemodynamic variables, and side effects were recorded for all the patients.

RESULTS

Postoperative VAS values at 24 hours were significantly lower in group M than group N (P < 0.0001). Sensory and Motor blocks onset and duration were statistically longer in group M than group N (P < 0.0001).

CONCLUSIONS

The addition of magnesium sulfate to lidocaine decreased the postoperative pain and increased the onset and duration of sensory and motor blocks in supraclavicular brachial plexus block under ultrasound guidance in upper limb surgeries.