Efficacy of Low Dose Levobupivacaine (0.1%) for Axillary Plexus Block using Multiple Nerve Stimulation

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.

Parecoxib added to ropivacaine prolongs duration of axillary brachial plexus blockade and relieves postoperative pain

BACKGROUND

Cyclooxygenase (COX)-2 antagonist is widely used for intravenous postoperative pain relief. Recent studies reported COX-2 in the spinal dorsal horn could modulate spinal nociceptive processes. Epidural parecoxib in rats showed no neurotoxicity. These findings suggested applying a COX-2 antagonist directly to the central or peripheral nerve might provide better analgesia.

QUESTIONS/PURPOSES

We therefore determined: (1) whether the addition of parecoxib to ropivacaine injected locally on the nerve block affected the sensory and motor block times of the brachial plexus nerve block; and (2) whether parecoxib injected locally on the nerve or intravenously had a similar analgesic adjuvant effect.

METHODS

We conducted a randomized controlled trial from January 2009 to November 2010 with 150 patients scheduled for elective forearm surgery, using a multiple-nerve stimulation technique. Patients were randomly allocated into one of three groups: Group A (n = 50) received ropivacaine 0.25% alone on the brachial plexus nerve; Group B (n = 50) received ropivacaine together with 20 mg parecoxib locally on the nerve block; and Group C (n = 50) received 20 mg parecoxib intravenously. We recorded the duration of the sensory and motor blocks, and the most severe pain score during a 24-hour postoperative period.

RESULTS

Parecoxib added locally on the nerve block prolonged the motor and sensory block times compared with Group A. However, parecoxib injected intravenously had no such effect. Pain intensity scores in Group B were lower than those in Groups A and C.

CONCLUSIONS

Parecoxib added to ropivacaine locally on the nerve block prolonged the duration of the axillary brachial plexus blockade and relieved postoperative pain for patients having forearm orthopaedic surgery.

LEVEL OF EVIDENCE

Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Regional Anaesthesia for Bilateral Upper Limb Surgery: A Review of Challenges and Solutions

Regional anaesthesia for bilateral upper limb surgery can be challenging, yet surgeons are becoming increasingly interested in performing bilateral procedures at the same operation. Anaesthetists have traditionally avoided bilateral brachial plexus block due to concerns about local anaesthetic toxicity, phrenic nerve block and pneumothorax. We discuss these three concerns and review whether advances in ultrasound guidance and nerve catheter techniques should make us reconsider our options. A search of Medline and EMBASE from 1966 to January 2009 was conducted using multiple search terms to identify techniques of providing anaesthesia or analgesia for bilateral upper limb surgery and potential side-effects. Ultrasound imaging and nerve catheter techniques have led to a reduction in dose requirements for effective blocks without side-effects. Effective regional anaesthesia can be performed for bilateral surgery while remaining within recommended safe dose limits. Spacing blocks apart in time can further reduce potential toxicity issues, such that peak absorption rates for each block do not coincide. Since phrenic nerve block remains an issue even with low doses of local anaesthesia, bilateral interscalene blocks are still not recommended. Peripheral nerve blocks have excellent safety profiles and are ideal for ultrasound guidance. Regional anaesthesia can be a suitable option for bilateral upper limb surgery.