Effect of tramadol as an adjuvant to local anesthetics for brachial plexus block: A systematic review and meta-analysis

Role of tramadol as an adjuvant in ultrasound-guided serratus anterior muscle block for modified radical mastectomy - A randomized control trial

Background and Aims

Modified radical mastectomy (MRM) is associated with significant acute post-operative pain that may progress to chronic pain syndromes in 25-60% of patients. Serratus anterior muscle (SAM) block has proved to be an excellent analgesic option in patients undergoing MRM. Although many adjuvants have been utilized for the prolongation of analgesia, the role of tramadol in SAM has not been studied as yet. We hypothesize that the addition of tramadol to ropivacaine for SAM block may reduce morphine consumption in the post-operative period in patients undergoing elective MRM surgeries. The primary aim of the study was to compare cumulative post-operative morphine consumption over 24 h in patients receiving SAM block with or without tramadol. The secondary aims were to observe adverse events related to the procedure or medications. The other parameters recorded were non-invasive blood pressure (NIBP), pulse rate, respiratory rate, and nausea or vomiting.

Material and Methods

Patients scheduled to undergo MRM were randomly allocated by block randomization into two groups. The study group (Group T) received a SAM block with 0.25% ropivacaine (18 ml) with tramadol 100 mg while the control group (Group P) received a SAM block with 18 ml of 0.25% ropivacaine and 2 ml of saline. Patients were assessed for pain scores, analgesic requirement, time to first analgesic request, hemodynamic variables, and any side-effects at 30 min, 1 h, 4 h, 8 h, 12 h, and 24 h post-operatively.

Results

Cumulative morphine consumption over 24 h in the post-operative period was less in the group T (3.06 ± 1.53 mg vs 4.34 ± 1.53 mg; P 0.001). Time to the first analgesic requirement was more in group T (10.44 ± 5.04 h vs 6.11 ± 2.73 h; P < 0.001). Pain scores were significantly lower in the group T at all time points.

Conclusion

Tramadol, when used as an adjuvant to ropivacaine for SAM block reduces post-operative pain scores in the first 24 h and prolongs the time of first morphine requirement.

Intraoperative and Postoperative Effects of Dexmedetomidine and Tramadol Added as an Adjuvant to Bupivacaine in Transversus Abdominis Plane Block

Background: We aimed to evaluate the intraoperative hemodynamics, opioid consumption, muscle relaxant use, postoperative analgesic effects, and possible adverse effects (such as nausea and vomiting) of dexmedetomidine and tramadol added as adjuvants to bupivacaine in the transversus abdominis plane block (TAP block) to provide postoperative analgesia. Materials and Methods: This was a prospective, randomized, controlled trial on patients who underwent laparoscopic cholecystectomy. After obtaining ethical approval at the Van Yuzuncu Yil University and written informed consent, this investigation was registered with ClinicalTrials.gov (NCT05905757). The study was conducted with 67 patients with ASA I-II physical status, aged 20-60 years, of either sex who were scheduled for an elective laparoscopic cholecystectomy under general anesthesia. Exclusion criteria were the patient's refusal, ASA III and above, a history of allergy to the study drugs, patients with severe systemic diseases, pregnancy, psychiatric illness, seizure disorder, and those who had taken any form of analgesics in the last 24 h. The patients were equally randomized into one of two groups: Group T (TAP Block group) and Group D (Dexmedetomidin group). Standard general anesthesia was administered. After intubation, Group T (Bupivacaine + adjuvant tramadol) = solutions containing 0.250% bupivacaine 15 mL + adjuvant 1.5 mg/kg (100 mg maximum) tramadol 25 mL and Group D (Bupivacaine + adjuvant dexmedetomidine) = solutions containing 0.250% bupivacaine 15 mL + 0.5 mcg/kg and (50 mcg maximum) dexmedetomidine 25 mL; in total, 40 mL and 20 mL was applied to groups T and D, respectively. A bilateral subcostal TAP block was performed by the same anesthesiologist. Intraoperative vital signs, an additional dose of opioid and muscle relaxant requirements, complications, postoperative side effects (nausea, vomiting), postoperative analgesic requirement, mobilization times, and the zero-hour mark (patients with modified Aldrete scores of 9 and above were recorded as 0 h), the third-hour, and sixth-hour visual analog scale (VAS) scores were recorded. The main outcome measurements were the effect on pain scores and analgesic consumption within the first 6 h postoperatively, postoperative nausea and vomiting (PONV), and time to ambulation. The secondary aim was to evaluate intraoperative effects (on hemodynamics and opioid and muscle relaxant consumption). Results: It was observed that dexmedetomidine and tramadol did not have superiority over each other in terms of postoperative analgesia time, analgesic consumption, side effect profile, and mobilization times (p > 0.05). However, more stable hemodynamics were observed with dexmedetomidine as an adjuvant. Conclusions: We think that the use of adjuvant dexmedetomidine in the preoperative TAP block procedure will provide more stable intraoperative hemodynamic results compared with the use of tramadol. We believe that our study will be a guide for new studies conducted with different doses and larger numbers of participants.

Peripheral nerve block adjuncts: which medication to choose? A narrative review of the current literature

Enhancing the effect of peripheral nerve blockade by adding other classes of medications has long history of trial and error. Studies have identified multiple potentially beneficial adjuncts that work to either speed the onset of analgesia or prolong its duration. The benefits of these adjuncts must be weighed against the risks of systemic negative side effects. To date, the most commonly used adjuncts, and ones with the most robust scientific efficacy are, dexamethasone, dexmedetomidine and buprenorphine. This narrative review will discuss several classes of local anesthetic adjuncts and provide evidence for the clinical efficacy and side effect profile of the most commonly studied medications.

Superior Laryngeal Nerve Block Response Rates in 54 Neurogenic Cough Patients

OBJECTIVE

Neurogenic cough related to hypersensitivity of the internal branch of the superior laryngeal nerve (SLN) is often treated with neuromodulating medications, which can cause considerable side effects. An alternative therapy is steroid and local anesthetic injection of the SLN ("SLN block"), initially proposed to benefit those with lateralizing symptoms (tenderness over the thyrohyoid membrane or unilateral cough source). Our objectives are to determine if SLN block produces subjective symptomatic improvements and if repeat injections further improve symptoms, and evaluate clinical factors potentially predictive of response.

METHODS

Retrospective chart review of 54 patients receiving SLN blocks at a tertiary medical academic center from January 2010 to June 2020. Medical history and anticipated predictors of positive response, including stigmata of laryngeal hypersensitivity, were recorded. Outcomes included symptomatic response, number of injections required, and side effects. Response was defined subjectively by asking patients whether the injection was beneficial and objectively by using CSI scores.

RESULTS

Fifty-four patients met the inclusion criteria. Thirty-eight patients (70.4%) endorsed improvement. No variables were identified as positive predictors of response. Thirty-two of the 38 (84.2%) endorsed improvement after one injection. Six of 15 (40%) patients who failed the first injection had positive response to the second. No significant side effects were reported.

CONCLUSION

No localizing symptoms, specific cough features, or aspects of the medical history helped predict response, suggesting that a broader range of patients may be offered the intervention. The majority of patients reported symptomatic improvement and repeat injections may benefit patients with initial nonresponse.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2647-2653, 2023.

Effect of Intramuscular Tramadol on the Duration of Clinically Relevant Sciatic Nerve Blockade in Patients Undergoing Calcaneal Fracture Fixation: A Randomized Controlled Trial

BACKGROUND

Calcaneal fracture fixation can generate severe postoperative pain and analgesia can be supported by a sciatic nerve block. However, following resolution of the sensory blockade, rebound pain may ensue. The aim of this study was to assess whether an incidental finding of two patients with an extension of the sciatic nerve block beyond 24 h following 100 mg of intramuscular tramadol administration could be confirmed.

METHODS

Thirty-seven patients scheduled for a calcaneal intramedullary fixation (Calcanail^®) were randomly divided into two groups. The tramadol group (n = 19) received a sciatic nerve block with 20 mL of 0.25% bupivacaine and a concomitant dose of 100 mg of intramuscular tramadol, while the control group (n = 18) received an identical sciatic nerve block with concomitant injection of normal saline (placebo). All patients had a spinal anesthesia with light sedation for the procedure. The time to first analgesic request defined as appearance of any pain (NRS > 0) was assessed as the primary endpoint with a clinically relevant expected result of at least 50% elongation in sensory blockade.

RESULTS

The median time to first analgesic request from time of blockade in the tramadol group was 670 min compared with 578 min in the control group. The result was clinically not relevant and statistically not significant (p = 0.17). No statistical difference could be demonstrated in the time to first opioid request, although a trend for opioid sparing in the tramadol group could be seen. Total morphine consumption in the first 24 h was also statistically insignificant (the tramadol group 0.066 mg kg^-1 compared with 0.125 mg kg^-1 in the control group). In conclusion, intramuscular tramadol does not extend the duration of analgesia of a sciatic nerve block following a calcaneal fracture fixation beyond 2 h and an opioid sparing effect could not be demonstrated in this trial.

Effect of Fentanyl as an Adjuvant to Brachial Plexus Block for Upper Extremity Surgeries: A Systematic Review and Meta-Analysis of RCTs

Objective. To assess if the addition of fentanyl to brachial plexus block has an impact on anesthetic outcomes and complication rates in patients undergoing upper extremity surgeries. Methods. We explore the PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar databases for all randomized controlled trials (RCTs) comparing adjuvant fentanyl with placebo/no drug for patients undergoing upper extremity surgery under brachial plexus block. Outcomes assessed were onset, duration of sensory and motor anesthesia, complications, and postoperative analgesia scores. Meta-analysis was conducted utilizing a random-effects model. The risk of bias was assessed using the Cochrane Collaboration’s risk of bias assessment tool 2. Certainty of evidence was assessed using GRADE. Subgroup analysis was conducted depending upon the approach of brachial plexus block and type of local anesthetic. Results. Twelve RCTs with 660 patients were included. Addition of fentanyl had no effect on onset of sensory anesthesia (11 studies; MD: 0.48; 95% CI: −1.81, 0.85; I2 = 96%; $p=0.48$ ) but significantly shortened onset of motor anesthesia (8 studies; MD: −2.36; 95% CI: −3.99, −0.74; I2 = 96%; $p=0.48$ ). Duration of sensory anesthesia (9 studies; MD: 82.81; 95% CI: 41.81, 123.81; I2 = 99%; $p<0.0001$ ) and motor anesthesia (7 studies; MD: 93.41; 95% CI: 42.35, 144.46; I2 = 99%; $p=0.0003$ ) was significantly increased with addition of fentanyl. The certainty of evidence-based on GRADE was deemed to be moderate for both onset and duration of anesthesia. The incidence of overall complications (nausea/vomiting and pruritis) was significantly higher in the fentanyl group (7 studies; OR: 2.14; 95% CI: 1.04, 4.40; I2 = 8%; $p=0.04$ ) but with low certainty of evidence. Conclusions. Adjuvant fentanyl with brachial plexus block improves the onset of motor anesthesia but not sensory anesthesia. The duration of both sensory and motor anesthesia is significantly prolonged with fentanyl by around 83–93 minutes. However, clinicians should be aware that complications such as nausea/vomiting and pruritis are increased twofold with the addition of the drug. Current evidence is limited risk of bias in the RCTs and high heterogeneity in the meta-analyses.

New Serotonin-Norepinephrine Reuptake Inhibitors and Their Anesthetic and Analgesic Considerations

Serotonin-norepinephrine reuptake inhibitors (SNRIs) inhibit the presynaptic neuronal uptake of serotonin and norepinephrine and prolong the effects of the monoamines in the synaptic cleft within the central nervous system, leading to increased postsynaptic receptor activation and neuronal activities. Serotonin-norepinephrine reuptake inhibitors can have multiple clinical indications, including as the first-line agents for the management of depression and anxiety, and as analgesics in the treatment of chronic pain. The effects of reuptake inhibition of norepinephrine and serotonin are often dose-dependent and agent-dependent. There are five FDA-approved serotonin-norepinephrine reuptake inhibitors (desvenlafaxine, duloxetine, levomilnacipran, milnacipran and sibutramine) currently being marketed in the United States. As the COVID-19 pandemic significantly increased the incidence and prevalence of anxiety and depression across the country, there are significantly increased prescriptions of these medications perioperatively. Thus, anesthesiologists are more likely than ever to have patients administered with these agents and scheduled for elective or emergency surgical procedures. A thorough understanding of these commonly prescribed serotonin-norepinephrine reuptake inhibitors and their interactions with commonly utilized anesthetic agents is paramount. There are two potentially increased risks related to the continuation of SNRIs through the perioperative period: intraoperative bleeding and serotonin syndrome. SNRIs have some off-label uses, more new indications, and ever-increasing new applications in perioperative practice. This article aims to review the commonly prescribed serotonin-norepinephrine reuptake inhibitors and the current clinical evidence regarding their considerations in perioperative anesthesia and analgesia.

Adjuvant Drugs for Peripheral Nerve Blocks: The Role of Alpha-2 Agonists, Dexamethasone, Midazolam, and Non-steroidal Anti-inflammatory Drugs

Adjuvant drugs for peripheral nerve blocks are a promising solution to acute postoperative pain and the transition to chronic pain treatment. Peripheral nerve blocks (PNB) are used in the brachial plexus, lumbar plexus, femoral nerve, sciatic nerve, and many other anatomic locations for site-specific pain relief. However, the duration of action of a PNB is limited without an adjuvant drug. The use of non-opioid adjuvant drugs for single-shot peripheral nerve blocks (sPNB), such as alpha-2 agonists, dexamethasone, midazolam, and non-steroidal anti-inflammatory drugs, can extend the duration of local anesthetics and reduce the dose-dependent adverse effects of local anesthetics. Tramadol is a weak opioid that acts as a central analgesic. It can block voltage-dependent sodium and potassium channels, cause serotonin release, and inhibit norepinephrine reuptake and can also be used as an adjuvant in PNBs. However, tramadol's effectiveness and safety as an adjuvant to local anesthetic for PNB are inconsistent. The effects of the adjuvants on neurotoxicity must be further evaluated with further studies to delineate the safety in their use in PNB. Further research needs to be done. However, the use of adjuvants in PNB can be a way to help control postoperative pain.

The Effect of Dexmedetomidine in Combination with Bupivacaine on Sensory and Motor Block Time and Pain Score in Supraclavicular Block

Background

Brachial plexus block is frequently recommended for upper limb surgeries. Many drugs have been used as adjuvants to prolong the duration of the block. This study aimed to assess the effect of dexmedetomidine with bupivacaine combination and only bupivacaine on sensory and motor block duration time, pain score, and hemodynamic variations in the supraclavicular block in upper extremity orthopedic surgery.

Methods

This prospective, double-blind clinical trial study was conducted on 60 patients, 20 to 60 years old. Patients were candidates for upper extremity orthopedic surgeries. The sensory and motor block were evaluated by using the pinprick method and the modified Bromage scale. The postoperative pain was assessed by utilizing a visual analog scale.

Results

The mean onset time of sensory and motor block in patients receiving only bupivacaine was, respectively, 31.03 ± 9.65 min and 24.66 ± 9.2 min, and in the dexmedetomidine receiving group, it was about 21.36 ± 8.34 min and 15.93 ± 6.36 minutes. The changes in heart rate and mean arterial blood pressure were similar in both groups. The duration of sensory and motor block and the time of the first analgesia request in the intervention group were longer. Postoperative pain was lower in the intervention group for 24 hours (P = 0.001).

Conclusion

Dexmedetomidine plus bupivacaine reduced the onset time of sense and motor blocks and increased numbness and immobility duration. Also, dexmedetomidine reduced postoperative pain significantly with the use of bupivacaine for supraclavicular blocks. Trial Registration. IRCT, IRCT20160430027677N15. Registered 05/28/2019, https://www.irct.ir/trial/39463.

Addition of 100 mg of Tramadol to 40 mL of 0.5% Ropivacaine for Interscalene Brachial Plexus Block Improves Postoperative Analgesia in Patients Undergoing Shoulder Surgeries as Compared to Ropivacaine Alone-A Randomized Controlled Study

Background and objectives: Brachial plexus block is commonly used in shoulder surgery, as it provides satisfactory surgical conditions and adequate postoperative pain control. However, there are contradictory reports regarding the addition of tramadol to the injected regional anesthetic solution. We performed a prospective randomized study to evaluate the effectiveness of tramadol as an adjuvant to ropivacaine during interscalene brachial plexus block and assess its impact on the opioid consumption and the early postoperative pain in patients that underwent shoulder surgery. Materials and Methods: Eighty patients scheduled for elective shoulder surgery and anesthesia via interscalene brachial plexus block were randomly divided into two groups. In group A (n = 40), a solution of 40 mL of ropivacaine 0.5% and 2 mL (100 mg) of tramadol was administered during the brachial plexus block, while in group B (n = 40), a solution of 40 mL of ropivacaine 0.5% and 2 mL NaCl 0.9% (placebo) was administered. The effectiveness and duration of sensory and motor blocks were recorded in both groups. The sensory block was assessed recording the loss of sensation to pin prick test over the skin distribution of the axillary, radial, and musculocutaneous nerves. The motor block was assessed using the modified 3-point Bromage score (0–2 points). Cumulative morphine consumption and pain, using the Visual Analog Scale (VAS), were evaluated in both groups at 2, 4, 8, and 24 h after surgery. Results: Sensory block onset was achieved earlier in group A than in group B (5.21 ± 3.15 minutes (min) vs. 7.1 ± 4.51 min, p = 0.029). The motor block onset was similar between the two groups (13.08 ± 6.23 min vs. 13.28 ± 6.59 min; p = 0.932). The duration of the sensory block was longer in group A as compared to group B (13 ± 2.3 h vs. 12 ± 2.8 h; p = 0.013). The duration of the motor block did not present any difference between the groups (10 ± 2.2 h vs. 10 ± 2.8 h; p = 0.308). Differences in morphine administration were not significant at 2, 4, and 8 h, however, morphine consumption was found to be decreased in group A 24 h postoperatively A (p = 0.04). The values of VAS were similar at 2, 4, and 8 h, however, they were lower in group A at 24 h (p < 0.013). Conclusions: Combined regional administration of tramadol and ropivacaine during interscalene brachial plexus block improves the time of onset and the duration of the sensory block, while it is associated with reduced morphine consumption during the first 24 h after shoulder surgery.

Neuroanesthesiology Update

We provide a synopsis of innovative research, recurring themes, and novel experimental findings pertinent to the care of neurosurgical patients and critically ill patients with neurological diseases. We cover the following broad topics: general neurosurgery, spine surgery, stroke, traumatic brain injury, monitoring, and anesthetic neurotoxicity.

Tramadol prescription patterns in patients followed by general practitioners and orthopedists in Germany in the year 2015

OBJECTIVES

The aim of this study was to analyze tramadol prescription patterns in acute pain patients followed by general practitioners and orthopedists in Germany.

METHODS

This study included patients ≥18 years diagnosed with acute pain who received at least one tramadol prescription each in one of 1,129 general or 179 orthopedic practices in Germany between January and December 2015 (index date). Patients were excluded if they had received a prescription for another analgesic in the year prior to the index date, had a follow-up of less than 15 months after the index date, or were prescribed tramadol for a period of more than three months. The main outcome of this retrospective study was the share of patients receiving tramadol in combination therapy. Combination therapy was defined as the prescription of tramadol in conjunction with at least one other analgesic during the same medical visit.

RESULTS

The present study included a total of 8,766 individuals. Overall, 1,492 (22.0%) of tramadol patients seen by general practitioners and 370 (18.7%) of those seen by orthopedists received tramadol in combination with other analgesics. Although this proportion was similar throughout the different subgroups in orthopedic practices, it was considerably higher in patients >80 years and in those with private health insurance coverage in general practices.

CONCLUSIONS

Approximately one of five tramadol patients was prescribed tramadol in combination therapy. Further research is needed to gain a better understanding of the demographic and clinical factors that have an effect on tramadol prescription patterns in Germany.