Peripheral nerve blocks for ambulatory surgery

Local anesthetic delivery systems for the management of postoperative pain

Postoperative pain (POP) is a major clinical challenge. Local anesthetics (LAs), including amide-type LAs, ester-type LAs, and other potential ion-channel blockers, are emerging as drugs for POP management because of their effectiveness and affordability. However, LAs typically exhibit short durations of action and prolonging the duration by increasing their dosage or concentration may increase the risk of motor block or systemic local anesthetic toxicity. In addition, techniques using LAs, such as intrathecal infusion, require professional operation and are prone to catheter displacement, dislodgement, infection, and nerve damage. With the development of materials science and nanotechnology, various LAs delivery systems have been developed to compensate for these disadvantages. Numerous delivery systems have been designed to continuously release a safe dose in a single administration to ensure minimal systemic toxicity and prolong pain relief. LAs delivery systems can also be designed to control the duration and intensity of analgesia according to changes in the external trigger conditions, achieve on-demand analgesia, and significantly improve pain relief and patient satisfaction. In this review, we summarize POP pathways, animal models and methods for POP testing, and highlight LAs delivery systems for POP management. STATEMENT OF SIGNIFICANCE: Postoperative pain (POP) is a major clinical challenge. Local anesthetics (LAs) are emerging as drugs for POP management because of their effectiveness and affordability. However, they exhibit short durations and toxicity. Various LAs delivery systems have been developed to compensate for these disadvantages. They have been designed to continuously release a safe dose in a single administration to ensure minimal toxicity and prolong pain relief. LAs delivery systems can also be designed to control the duration and intensity of analgesia to achieve on-demand analgesia, and significantly improve pain relief and patient satisfaction. In this paper, we summarize POP pathways, animal models, and methods for POP testing and highlight LAs delivery systems for POP management.

Pain Management and Opioid Use with Long-Acting Peripheral Nerve Blocks for Hand Surgery: A Descriptive Study

Background

Peripheral nerve blocks (PNBs) are used in multiple surgical fields to provide a high level of regional pain relief with a favorable adverse effect profile. Peripheral nerve blocks aim to decrease overall perioperative pain and lower systemic analgesic requirements. Short-acting anesthetic agents are commonly given as single-injection PNBs for pain relief, typically lasting less than 24 hours. Liposomal bupivacaine is a newer anesthetic formulation lasting up to 72 hours as a single-injection PNB and may allow patients to recover postoperatively with a lower need for opioid analgesics.

Objectives

This study investigates peri- and postoperative pain and opioid use in patients receiving a long-acting brachial plexus PNB for hand surgery.

Methods

A retrospective review of patients who underwent a long-acting PNB using liposomal bupivacaine in the brachial plexus for minor hand operations was performed between July 2020 and May 2023 in Florida, USA. Patients were administered a ten-question survey regarding perioperative pain levels, post-operative symptoms, patient satisfaction, postoperative opioid use, and postoperative non-opioid analgesics.

Results

One hundred three patients, including 21 males and 82 females with an average age of 68.3 ± 15.8 years, completed a survey (34.2% response rate). Patients reported a considerable reduction in pain from 7.9 ± 2.2 out of ten before the PNB to 1.6 ± 1.8 in the perioperative period, 4.3 ± 2.7 in postoperative days zero to three, and 3.8 ± 2.4 in postoperative days four and five. Nerve block effects lasted a mean of 2.2 ± 2.0 days and patients reported a high level of satisfaction regarding their pain management plan with a score of 9.4 ± 1.4 out of ten. 20.4% of patients were prescribed opioids and 41.7% used NSAIDs postoperatively.

Conclusions

Liposomal bupivacaine PNBs effectively reduced peri- and postoperative pain with pain relief lasting 2.2 ± 2.0 days. Patients were highly satisfied with their pain management and there was a low rate of postoperative opioid prescription. Given these results, long-acting PNBs have the potential to significantly improve patient satisfaction, reduce anesthesia use, and reduce postoperative opioid prescription.

Can ultrasound-guided infraclavicular block be an alternative option for forearm reduction in the emergency department? A prospective randomized study

Objective

Ultrasound-guided infraclavicular nerve block (IB) has become a well-established method in several outpatient procedures; however, its use in emergency departments (EDs) remains limited. The aim of this study was to compare procedural sedation and anlagesia (PSA) and IB in the pain management for patients who underwent forearm fracture reduction in the ED.

Methods

This prospective randomized study included 60 patients aged 18 to 65 years, who visited the ED with forearm fractures. They were randomly divided into two groups: Group PSA (n=30) and Group IB (n=30). The pain scores of patients were evaluated before and during the procedure with the visual analog scale. Complications and patient and operator satisfaction levels were recorded.

Results

There was no difference between the two groups in terms of demographic characteristics. The median (interquartile range) pain scores observed during the procedures were significantly higher in Group PSA than in Group IB (4 [4–6] vs. 2 [0–2], respectively; P<0.001). Patient and operator satisfaction levels were significantly higher in Group IB (P<0.001). Oxygen desaturation was statistically higher in Group PSA than in Group IB (40.00% vs. 3.33%, respectively; P=0.002).

Conclusion

IB was an effective alternative for reducing pain and increasing patient satisfaction in ED patients undergoing forearm fracture reduction.

Perineural dexamethasone reduces rebound pain after ropivacaine single injection interscalene block for arthroscopic shoulder surgery: a randomized controlled trial

BACKGROUND AND OBJECTIVES

A single injection interscalene block (ISB) is a common regional analgesic technique in patients undergoing arthroscopic shoulder surgery. However, rebound pain after ISB resolution may reduce its overall benefit. Our primary aim was to assess whether perineural dexamethasone reduces the intensity and incidence of rebound pain in patients undergoing arthroscopic shoulder surgery under general anesthesia combined with a preoperative single injection ISB.

METHODS

The patients were randomly assigned to receive single injection ISB using either 0.5% ropivacaine (control) or 0.5% ropivacaine containing 5 mg of dexamethasone. The primary outcomes were the pain score difference before and after ISB resolution, and the incidence of rebound pain. The secondary outcomes were the onset and duration of rebound pain, the presence of sleep disturbances due to postoperative pain, the first time when an analgesic was requested, and pain scores at various predefined time points.

RESULTS

Pain increase following ISB resolution was lower in the dexamethasone group compared with the control group (4.5±2.4 and 6.9±2.2, respectively, p<0.001). The incidence of rebound pain was significantly lower in the dexamethasone group compared with the control group (37.1% and 82.9%, respectively, p<0.001). The controls experienced greater sleep disturbance during the postoperative period compared with those who received ISB with perineural dexamethasone.

CONCLUSIONS

Perineural dexamethasone added to ISB using ropivacaine led to a much smoother resolution of ISB, reflected in a significantly smaller increase in pain after block resolution, a lower incidence of rebound pain and a lower sleep disturbance during the first postoperative week.

TRIAL REGISTRATION NUMBER

Clinical Trial Registry of Korea (KCT0004418).

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

Low-concentration distal nerve blocks with 0.125% levobupivacaine versus systemic analgesia for ambulatory trapeziectomy performed under axillary block: a randomized controlled trial

BACKGROUND

Trapeziectomy is one of the most painful procedures in ambulatory surgery. This prospective randomized trial aimed to compare postoperative pain control using distal peripheral nerve blocks (dPNB) with a low concentration of a long-acting local anesthetic versus conventional systemic analgesia.

METHODS

Fifty-two patients undergoing trapeziectomy were randomized to receive levobupivacaine 0.125% 5 mL on radial and median nerves at the elbow (dNB group), or not to receive these blocks (control group). In both groups, surgery was performed under axillary block (mepivacaine 1% 20 mL) and the same analgesic regimen was prescribed at discharge. The primary outcome was postoperative pain at 24 and 48 hours after surgery and maximum pain score on the first and second postoperative day. Secondary outcomes were duration of dPNB, rescue analgesia requirements, opioid-related side effects, consumption and effectiveness of antiemetic therapy, and upper limb motor block.

RESULTS

Fifty patients were analyzed. Maximum pain intensity was moderate to severe (dPNB vs. control) in 33.3% vs. 92.3% (P=0.002) on the first day after surgery and 20.8% vs. 80.8% (P<0.001) on the second day. The average duration of analgesia after dPNB was 10 hours and no patient reported motor block. dPNB reduced rescue analgesia requirements and the incidence of postoperative nausea and vomiting (PONV).

CONCLUSIONS

dPNB on target nerves provided better analgesia than systemic analgesia after trapeziectomy performed under axillary block. Opioid consumption and the incidence of PONV were lower in the dPNB group.

Scrambler therapy for the treatment of neuropathic pain related to leukemia in a pediatric patient: A case report

RATIONALE

Cancer-related neuropathic pain often responds poorly to standard pain treatments. Scrambler therapy has relieved refractory chronic pain in several uncontrolled clinical trials.

PATIENT CONCERNS

An 11-year-old female patient was suffering from left groin and medial thigh pain after irradiation to the knee. The girl was diagnosed with precursor B-cell lymphoblastic leukemia 2 years ago. Extramedullary relapse of leukemia developed 1 month ago and pain had started. She was treated with oral medications, but she was continuously complaining of severe pain.

DIAGNOSIS

Neuropathic pain caused by obturator nerve involvement in leukemia.

INTERVENTION

Scrambler therapy.

OUTCOME

Pain reduction.

LESSONS

Scrambler therapy is noninvasive, is not associated with any complications, causes minimal discomfort during treatment, and is very effective in a pediatric patient with cancer-related neuropathic pain.

Ropivacaine versus levobupivacaine in peripheral nerve block: A PRISMA-compliant meta-analysis of randomized controlled trials

BACKGROUND

To determine which is more potent in peripheral nerve block between ropivacaine and levobupivacaine.

METHODS

A literature search was performed in the EMBASE, Medline, the Cochrane Library, and the Web of Science. The trials that were found were then evaluated for eligibility. The Cochrane Collaboration's Review Manager software was used to perform the meta-analyses.

RESULTS

Twelve studies including 556 patients were included for final analysis. No statistically significant difference was observed between the 2 drugs with respect to onset time of surgical anesthesia, onset time of sensory block, onset time of motor block, duration of motor block, and patients overall satisfaction. Levobupivacaine provided more long-term anesthesia (weighted mean difference [WMD], -2.94; 95% confidence interval [CI], -5.56 to -0.32; I = 93%) and significantly lower incidence of postoperative rescue analgesia (odds ratio [OR], 2.11; 95% CI 1.18-3.74; I = 21%) than ropivacaine. There was a trend toward greater duration of sensory block in the levobupivacaine group (WMD, -1.16; 95% CI, -1.89 to -0.43; I = 14%).

CONCLUSION

Levobupivacaine is more potent than ropivacaine in peripheral nerve block to some extent. Otherwise, more rigorous randomized control trials are required in the future.