Axillary Brachial Plexus Block for Olecranon Plating
Primary Recommendation
A pure ultrasound-guided axillary brachial plexus block is suitable and effective for both anesthesia and postoperative analgesia in olecranon fracture plating, provided you use a multiple-injection technique targeting all four terminal nerves and combine it with multimodal systemic analgesia. 1, 2
Technical Approach
Block Technique
Use ultrasound-guided multiple-injection technique targeting the musculocutaneous, median, radial, and ulnar nerves individually, as single-injection axillary blocks historically fail to provide reliable blockade in the musculocutaneous and radial territories 1
Inject 5-8 mL of local anesthetic around each of the four terminal nerves under direct ultrasound visualization, for a total volume of 20-35 mL 1
Choose long-acting local anesthetics such as ropivacaine 0.5% or bupivacaine 0.5% to provide extended postoperative analgesia lasting 12-18 hours 3
The axillary approach is the safest brachial plexus block option because it cannot cause pneumothorax or phrenic nerve blockade, making it ideal for outpatient surgery 1
Critical Anatomical Coverage
The axillary block reliably provides cutaneous anesthesia of the inner upper arm including the medial cutaneous nerve of arm and intercostobrachial nerve, which are essential for the posterior surgical approach to the olecranon 1
Success rates for axillary block in elbow surgery reach 89% when proper technique is used, which is actually superior to supraclavicular (78%) and interscalene (75%) approaches for this anatomical region 2
Blocks using paresthesia technique or nerve stimulator combined with ultrasound guidance achieve 94-95% success rates, compared to 81% with transarterial injection alone 2
Multimodal Systemic Analgesia Protocol
Pre-operative and Intra-operative Medications
Administer paracetamol (acetaminophen) 1000 mg IV pre-operatively or intra-operatively and continue every 6 hours postoperatively as the foundation of pain management 4
Give COX-2 inhibitors or NSAIDs (such as celecoxib or naproxen) pre-operatively unless contraindicated, and continue postoperatively on a scheduled basis rather than as-needed to maintain stable serum levels 4
Administer intravenous dexamethasone 8-10 mg intra-operatively to prolong the duration of the nerve block, reduce analgesic requirements, and provide anti-emetic effects 4, 3
Postoperative Opioid Strategy
Reserve opioids exclusively for breakthrough pain that is not controlled by the nerve block and non-opioid analgesics 4
Use the lowest effective opioid dose for the shortest duration, as opioid-sparing strategies reduce side effects including respiratory depression, nausea, and postoperative confusion 4, 5
In elderly patients over 55 years, reduce opioid doses by 20-25% per decade to account for altered pharmacokinetics and increased sensitivity 4
Monitoring and Sedation
Intra-operative Management
Provide minimal or no sedation during the block procedure and surgery to reduce the risk of respiratory depression and postoperative delirium, particularly in elderly patients 5, 6
If sedation is required, use cautious doses of midazolam or propofol, recognizing that elderly patients are more sensitive to these agents 4
Maintain continuous monitoring including pulse oximetry, ECG, and non-invasive blood pressure every 3-5 minutes throughout the procedure 4, 6
Supplemental Oxygen
- Always provide supplemental oxygen during the procedure, as intra-operative hypoxemia is common even with regional anesthesia 4
Alternative Strategies When Pure Axillary Block Is Insufficient
Conversion to General Anesthesia
If the axillary block fails or proves inadequate intra-operatively, convert to general anesthesia using reduced doses of induction agents 4, 6
Consider inhalational induction to preserve spontaneous ventilation and avoid the hemodynamic instability associated with rapid-sequence induction 4
Never combine spinal or general anesthesia simultaneously with the brachial plexus block, as this causes precipitous hypotension 5, 6
Continuous Catheter Technique
For complex olecranon plating procedures or patients at high risk for severe postoperative pain, consider placing a continuous axillary catheter for prolonged local anesthetic infusion 7
Continuous peripheral nerve blocks facilitate major operations on an outpatient basis and provide extended pain relief beyond single-injection techniques 7
This requires patient education, basic infusion pumps, and a mechanism for follow-up after discharge 7
Critical Pitfalls to Avoid
Do not use single-injection axillary technique, as it fails to reliably block the musculocutaneous and radial nerves, which are essential for olecranon surgery 1
Do not rely on transarterial injection alone, as it has only an 81% success rate compared to 94-95% with nerve stimulation or ultrasound-guided paresthesia techniques 2
Do not use opioids as the sole adjunct to regional anesthesia, as this creates extreme risk of respiratory depression and confusion without addressing the underlying need for multimodal analgesia 5, 6
Do not skip the medial cutaneous nerve of arm and intercostobrachial nerve, as these provide sensation to the posterior upper arm where the surgical incision and tourniquet are placed 1
Do not forget to verify coagulation status before performing the block in anticoagulated patients, though axillary blocks are safer than neuraxial techniques in this population 3, 6
Special Considerations for Elderly Patients
Elderly patients undergoing olecranon plating benefit particularly from regional anesthesia because it avoids airway manipulation and reduces postoperative confusion compared to general anesthesia 4
Peripheral nerve blocks reduce pain on movement, risk of acute confusional state, chest infection, and time to first mobilization in elderly trauma patients 4
The axillary approach is more amenable to ultrasound guidance and continuous catheter placement than proximal approaches, making it ideal for elderly patients who may need extended analgesia 4