What is the most appropriate brachial plexus block technique for a 56-year-old female undergoing wide resection of the humerus due to high-grade spindle cell sarcoma?

Brachial Plexus Block Selection for Humeral Resection in High-Grade Spindle Cell Sarcoma

For wide resection of the humerus in this 56-year-old female with high-grade spindle cell sarcoma, the supraclavicular brachial plexus block is the optimal choice, providing complete anesthesia of the entire upper extremity with the most consistent and time-efficient coverage of all humeral regions required for this extensive oncologic resection. 1, 2

Supraclavicular Block: The Preferred Approach

The supraclavicular approach targets the brachial plexus at its most compact anatomical arrangement in the supraclavicular fossa, where trunks and divisions are tightly clustered, making it ideal for humeral shaft surgery. 2, 3

Key Advantages for This Case:

• Provides complete anesthesia of the entire upper extremity in the most consistent, time-efficient manner of any brachial plexus technique 2
• Achieves 92% success rate compared to 56-86% for axillary blocks 4
• Significantly reduced total anesthesia-related time compared to infraclavicular approach 1
• Ensures reliable coverage of all humeral regions (proximal, mid-shaft, and distal) required for wide oncologic resection 5, 3
• High success rate for ulnar and musculocutaneous nerve blockade, which can be missed with other approaches 3

Technical Considerations:

• Ultrasound guidance is mandatory to visualize pleura and reduce pneumothorax risk (historically the main concern with this approach) 6, 3
• Use nerve stimulation with minimal threshold of 0.9 mA 5
• Multiinjection intracluster technique reduces complications without increasing performance time 1
• Ropivacaine 0.75% at 20-30 mL provides 11.4-14.4 hours of anesthesia 4, 1

Infraclavicular Block: Second-Line Alternative

The infraclavicular approach is a reasonable alternative but offers no superiority for this specific case. 1, 5

Characteristics:

• Requires significantly more needle passes and injection numbers compared to supraclavicular approach 1
• Provides longest block duration (beneficial for postoperative analgesia) 1
• Most effective for maintaining continuous catheter placement if extended postoperative analgesia is planned 2
• Double-stimulation technique (targeting lateral and posterior cords) is optimal 5
• Ropivacaine 7.5 mg/mL at 30 mL (225 mg) via subclavian perivascular approach provides 11.4-14.4 hours anesthesia 4

When to Consider:

• If continuous catheter technique is planned for extended postoperative pain management in this oncologic case 2
• Patient positioning constraints make supraclavicular access difficult 5

Axillary Block: Inadequate for This Surgery

The axillary approach is inappropriate for humeral resection as it is most effective only for surgical procedures distal to the elbow. 2

Critical Limitations:

• Significantly lower success rate (56-86%) compared to supraclavicular (92%) 4
• Poorest nerve visibility among all approaches 1
• Requires triple-stimulation technique (musculocutaneous, median, radial nerves) for optimal efficacy 5
• Median onset ranges from 10-45 minutes depending on nerve distribution 4
• Inadequate proximal humeral coverage for wide resection surgery 2, 5

Only Appropriate For:

• Forearm and hand surgery 2
• Patients where supraclavicular/infraclavicular approaches are contraindicated 6

Interscalene Block: Contraindicated for This Case

Interscalene block is specifically designed for shoulder and proximal humerus surgery but provides inadequate coverage of mid-shaft and distal humerus required for wide resection. 7, 2

Why It Fails for Humeral Resection:

• Designed for rotator cuff repair and shoulder arthroplasty, not extensive humeral resection 7
• Incomplete blockade of inferior trunk (C8-T1), resulting in poor ulnar nerve coverage 2, 5
• Inadequate anesthesia for mid-shaft and distal humeral regions 2
• Highest risk of complications: needle positioned near centroneuraxis and cerebral arteries 2
• Symptomatic diaphragmatic paralysis is more common 6

Only Appropriate For:

• Isolated shoulder surgery (rotator cuff repair, shoulder arthroplasty) 7
• Proximal humeral procedures not extending beyond surgical neck 2

COVID-19 Era Considerations

If performing regional anesthesia during pandemic conditions or in immunocompromised patients (relevant given oncologic surgery): 7

• Supraclavicular and infraclavicular blocks are preferred over interscalene to minimize respiratory compromise 7
• Axillary or infraclavicular approaches preferred over supraclavicular if respiratory function preservation is critical 7
• Ultrasound guidance mandatory to reduce local anesthetic systemic toxicity risk 7

Adjunctive Recommendations

Pharmacologic Enhancement:

• Single-dose IV dexamethasone increases analgesic duration of brachial plexus block and provides anti-emetic effects 7
• Multimodal analgesia with paracetamol and NSAIDs should be administered pre-operatively 7
• Opioids reserved as rescue analgesia 7

Critical Pitfall to Avoid:

Never perform regional anesthesia before the patient has been evaluated by the specialized sarcoma multidisciplinary team, as this is a high-grade spindle cell sarcoma requiring coordinated oncologic management. 8, 9 The anesthetic plan must be integrated with the surgical oncology team's approach to ensure optimal positioning, tourniquet use, and potential for limb salvage versus amputation. 7