A Randomized, Prospective, Double-Blind Trial Comparing 3% Chloroprocaine Followed by 0.5% Bupivacaine to 2% Lidocaine Followed by 0.5% Bupivacaine for Interscalene Brachial Plexus Block

A randomised trial comparing block characteristics of a mixture versus sequential injections of lignocaine and ropivacaine for supraclavicular brachial plexus nerve block in patients undergoing upper limb surgery

Background and Aim

There is no consensus on the appropriate use of mixtures of local anaesthetic drugs in various combinations for nerve blocks. We intended to compare short-acting lignocaine and long-acting ropivacaine as a mixture versus undiluted sequential injections on block characteristics of ultrasound-guided (USG) supraclavicular brachial plexus block for upper limb surgeries.

Methods

A double-blinded randomised study was conducted on 64 adult patients scheduled for upper limb surgery who received 15 mL each of 2% lignocaine with adrenaline and 0.75% ropivacaine as a 1:1 mixture in the mixed group (Group M) or sequential injections in the sequential group (Group S) by using a USG technique. The primary outcome was the percentage of participants with complete four nerve sensory blocks at 10 minutes post block injection. Secondary outcomes were sensory and motor block characteristics till 30 minutes, total duration of analgesia, sensory and motor block, and complications.

Results

Demographic characteristics and time taken for the procedure were similar. The percentage of participants with a complete four-nerve sensory block at 10 minutes was higher in Group S (69%) versus Group M (41%) (P = 0.04). Complete sensory and motor block rates were similar at 30 minutes. The block procedure time, total duration of analgesia, and sensory and motor block were similar in both groups. There were no major complications.

Conclusion

Sequential lignocaine-ropivacaine, compared to the mixed injection technique, has a higher initial rate of sensory and motor block onset with a similar total block duration.

Superior Trunk Block Catheter and 2% Chloroprocaine as a Phrenic Sparing Approach for Awake Arthroscopic Acromioclavicular Joint Surgery: A Case Report

Regional anaesthesia for shoulder surgery remains challenging in patients with pre-existing respiratory comorbidities. Various alternative phrenic sparing techniques have been described in the literature, but to our knowledge, none have explored the benefits of using short-acting local anaesthetics in combination to achieve surgical anaesthesia for awake surgery. This case report describes the successful use of the superior trunk block catheter, a relative phrenic sparing shoulder nerve block, and 2% chloroprocaine, a short-acting local anaesthetic, to provide surgical anaesthesia for awake shoulder surgery in a patient with severe respiratory disease.

What Is the Risk of Postoperative Neurologic Symptoms After Regional Anesthesia in Upper Extremity Surgery? A Systematic Review and Meta-analysis of Randomized Trials

BACKGROUND

The risk of neurologic symptoms after regional anesthesia in orthopaedic surgery is estimated to approach 3%, with long-term deficits affecting 2 to 4 per 10,000 patients. However, current estimates are derived from large retrospective or observational studies that are subject to important systemic biases. Therefore, to harness the highest quality data and overcome the challenge of small numbers of participants in individual randomized trials, we undertook this systematic review and meta-analysis of contemporary randomized trials.

QUESTIONS/PURPOSES

In this systematic review and meta-analysis of randomized trials we asked: (1) What is the aggregate pessimistic and optimistic risk of postoperative neurologic symptoms after regional anesthesia in upper extremity surgery? (2) What block locations have the highest and lowest risk of postoperative neurologic symptoms? (3) What is the timing of occurrence of postoperative neurologic symptoms (in days) after surgery?

METHODS

We searched Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews, Web of Science, Scopus, and PubMed for randomized controlled trials (RCTs) published between 2008 and 2019 that prospectively evaluated postoperative neurologic symptoms after peripheral nerve blocks in operative procedures. Based on the Grading of Recommendations, Assessment, Development, and Evaluation guidance for using the Risk of Bias in Non-Randomized Studies of Interventions tool, most trials registered a global rating of a low-to-intermediate risk of bias. A total of 12,532 participants in 143 trials were analyzed. Data were pooled and interpreted using two approaches to calculate the aggregate risk of postoperative neurologic symptoms: first according to the occurrence of each neurologic symptom, such that all reported symptoms were considered mutually exclusive (pessimistic estimate), and second according to the occurrence of any neurologic symptom for each participant, such that all reported symptoms were considered mutually inclusive (optimistic estimate).

RESULTS

At any time postoperatively, the aggregate pessimistic and optimistic risks of postoperative neurologic symptoms were 7% (915 of 12,532 [95% CI 7% to 8%]) and 6% (775 of 12,532 [95% CI 6% to 7%]), respectively. Interscalene block was associated with the highest risk (13% [661 of 5101] [95% CI 12% to 14%]) and axillary block the lowest (3% [88 of 3026] [95% CI 2% to 4%]). Of all symptom occurrences, 73% (724 of 998) were reported between 0 and 7 days, 24% (243 of 998) between 7 and 90 days, and 3% (30 of 998) between 90 and 180 days. Among the 31 occurrences reported at 90 days or beyond, all involved sensory deficits and four involved motor deficits, three of which ultimately resolved.

CONCLUSION

When assessed prospectively in randomized trials, the aggregate risk of postoperative neurologic symptoms associated with peripheral nerve block in upper extremity surgery was approximately 7%, which is greater than previous estimates described in large retrospective and observational trials. Most occurrences were reported within the first week and were associated with an interscalene block. Few occurrences were reported after 90 days, and they primarily involved sensory deficits. Although these findings cannot inform causation, they can help inform risk discussions and clinical decisions, as well as bolster our understanding of the evolution of postoperative neurologic symptoms after regional anesthesia in upper extremity surgery. Future prospective trials examining the risks of neurologic symptoms should aim to standardize descriptions of symptoms, timing of evaluation, classification of severity, and diagnostic methods.

LEVEL OF EVIDENCE

Level I, therapeutic study.

Comparative Study of Intravenous Dexmedetomidine Sedation With Perineural Dexmedetomidine on Supraclavicular Approach Brachial Plexus Block in Upper Limb Orthopaedic Surgery

Background

Dexmedetomidine is being used as an adjuvant analgesic, both as intravenous (IV) and intrathecal infusion. The role of perineural (P) dexmedetomidine has evoked attention recently. The aim of this study was to compare the effect of IV dexmedetomidine and P dexmedetomidine as an adjunct to supraclavicular brachial plexus block in upper limb orthopaedic surgery. 

Methods

Patients were randomly divided into two equal groups (n=20). Group I (IV dexmedetomidine) received dexmedetomidine 1 mcg/kg IV as loading dose over 10 minutes, followed by continuous infusion of dexmedetomidine 0.4 mcg/kg/hr IV. Group P (P dexmedetomidine) received dexmedetomidine at 1 mcg/kg perineurally. After adequate motor response with the aid of peripheral nerve stimulator a supraclavicular block with 40 ml solution containing 5 mg/kg lignocaine (2%) with adrenaline (1:200,000) and 2 mg/kg of bupivacaine (0.5%) was injected to both the groups. Group P also received dexmedetomidine perineurally with block. Onset and duration of sensory and motor block, Ramsay sedation score, hemodynamic parameters, and postoperative analgesia requirement were assessed along with side effects. The data obtained were recorded as mean ± SD, ranges, numbers, and ratios. Results were analyzed using the chi-square test, the Mann-Whitney test for non-parametric data, and an unpaired ‘t’-test for parametric data. Statistical analysis was carried out using the SPSS (version 10, 2002; SPSS Inc., Chicago, IL, USA) for Windows statistical package. P value less than 0.05 was considered statistically significant. 

Results

Mean onset of sensory block was earlier in group I than in group P (p<0.05) although mean onset of motor block was not significantly different (p>0.05). Duration of sensory and motor blockade was longer in group I (p<0.05). Patients in group I demonstrated lower pulse rate and lower systolic and diastolic blood pressures throughout the period with comparable SpO₂ values. There was no difference in intraoperative Ramsay sedation scores in both groups, but postoperative Ramsay sedation scores at 9, 12, and 15 hours were better in group I (p<0.05). The average time to rescue analgesia (visual analogue scale >4) was higher in group I (p>0.05).

Conclusion

IV dexmedetomidine produced early onset of sensory block, longer duration of sensory and motor block, and longer duration of analgesia as compared with P dexmedetomidine as an adjuvant to supraclavicular block with 5 mg/kg lignocaine (2%) and 2 mg/kg bupivacaine (0.5%) in upper limb orthopaedic surgeries.

Bilateral Brachial Plexus Block Using Chloroprocaine For Surgery Of Bilateral Radial Fractures

We report a case of a 41-year-old male with anticipated difficult airway undergoing a repair of a bilateral radial fracture under bilateral sequential brachial plexus block. Anesthesiologists are reluctant to perform bilateral blocks because of the fear of complications like diaphragmatic paralysis, local anesthetic (LA) toxicity, and pneumothorax. We advise that with the correct application of LA pharmacokinetics, careful patient selection and usage of ultrasound, bilateral blocks can be done safely. We used chloroprocaine as an LA in one of the blocks to reduce the dose required for the more toxic LAs. chloroprocaine’s fast metabolism also helped us to prevent the overlapping of peak plasma concentration of different LAs. To our knowledge, this is the first reported case in the literature where chloroprocaine was used for bilateral brachial plexus block.

Surgical Treatment of Distal Radius Fractures under the Ultrasound-Guided Brachial Plexus Block Performed by Surgeons

Background: The upper limb surgery under the ultrasound-guided brachial plexus block is becoming popular due to its safety, effectiveness, and convenience. However, the uneven distribution of anesthesiologists become a social problem. Ultrasound-guided brachial plexus block by surgeons has been widespread especially in hand surgeons. We report the surgical treatment of distal radius fractures under the ultrasound-guided brachial plexus block performed by surgeons in our hospital. Methods: The subjects were 101 patients (41 males and 60 females, average age 61.6 years) who underwent surgery for distal radius fractures under ultrasound-guided brachial plexus block administered by orthopedists at our university or related facilities between January 2014 and June 2016. Brachial plexus block was administered through the supraclavicular approach. The time from initiation of anesthesia to initiation of surgery, mean operative time, the presence or absence of additional anesthesia (local infiltration anesthesia, intravenous anesthesia, and general anesthesia), and complications were evaluated. Results: The mean time from brachial plexus block to initiation of surgery was 35.7 (20-68) minutes, and the mean operative time was 90.5 (35-217) minutes. Surgery was completed with brachial plexus block alone in 62 patients (61.4%), and additional anesthesia was necessary in 39 patients (38.6%). Furthermore, general anesthesia was employed in 6 patients (5.9%). No serious complications occurred. Conclusions: According to our results, the operation could be completed with brachial plexus block alone and additional local infiltration anesthesia or intravenous anesthesia in 94.1% (95 cases). However, 6 cases (5.9%) shifted to general anesthesia. Although it needs training, we consider that hand surgery including distal radius fractures treatment under the ultrasound-guided brachial plexus block is possible. On the other hand, cooperation or a cooperative system with anesthesiologists is necessary for surgeons to administer this anesthesia.