What is the recommended anesthesia approach for a 56-year-old female with high-grade spindle cell sarcoma undergoing wide resection of the humerus?

Recommended Anesthesia Approach for Humeral Sarcoma Resection

For a 56-year-old female undergoing wide resection of high-grade spindle cell sarcoma of the humerus, the recommended approach is combined supraclavicular brachial plexus block with general anesthesia, as this provides superior intraoperative conditions, complete airway protection, and effective postoperative analgesia for 12-18 hours. 1

Primary Anesthetic Technique

The supraclavicular approach is specifically indicated for mid-shaft humeral surgery, as it provides complete coverage from mid-humerus distally, which is essential for wide resection procedures. 2 The interscalene block should be avoided because it is designed for shoulder and proximal humerus only and provides inadequate coverage of mid-shaft and distal humerus required for wide resection. 3

• General anesthesia must be combined with the regional block for major oncologic resections to ensure complete patient immobility and airway protection during this complex procedure. 1
• The combined technique reduces the dose of hypnotic agents required for induction, which is particularly important in this 56-year-old patient, as elderly patients require lower doses and have longer onset times. 1

Key Studies Supporting Supraclavicular Block for Humeral Surgery

Study 1: Brachial Plexus Blocks Review (2007)

A comprehensive systematic review of randomized controlled trials published in the Canadian Journal of Anaesthesia evaluated all established approaches to brachial plexus anesthesia. 4 This review found that:

• For surgery at or below the mid-humerus, supraclavicular blocks provide effective surgical anesthesia with decreased performance time compared to other approaches. 4
• The supraclavicular approach provides more complete anesthesia of the brachial plexus compared to other techniques. 4
• Nerve stimulation with a minimal threshold of 0.9 mA is specifically recommended for supraclavicular blocks to ensure proper nerve localization. 4

Study 2: Ultrasound-Guided Selective Trunk Block (2020)

A case report published in A&A Practice described ultrasound-guided selective trunk block for intramedullary nailing of a pathological humeral fracture, demonstrating that:

• None of the classical single brachial plexus block techniques can reliably produce surgical anesthesia of the whole upper extremity from shoulder to hand. 5
• The selective trunk block technique, which involves individually identifying and blocking the three trunks of the brachial plexus with two separate injections, successfully produced surgical anesthesia of the entire upper extremity. 5
• This approach is viable when complete upper extremity anesthesia is required, providing coverage except for the intercostobrachial nerve (T2) territory. 5

Critical Safety Considerations

Local Anesthetic Toxicity Risk

• Ropivacaine plasma concentrations may approach the threshold for central nervous system toxicity after administration of 300 mg for brachial plexus block, requiring careful dose adjustment. 6
• Supraclavicular brachial plexus blocks are associated with a higher frequency of serious adverse reactions regardless of the local anesthetic used, necessitating heightened vigilance. 6
• Injections must be made slowly and incrementally with frequent aspirations before and during injection to avoid intravascular injection, as an intravascular injection is still possible even if aspirations for blood are negative. 6

Age-Related Precautions

• This 56-year-old patient is at higher risk of preventable peripheral nerve injuries during prolonged surgery, including brachial plexus injury from prolonged lateral neck flexion. 1
• Debilitated and elderly patients should receive reduced doses of local anesthetics commensurate with their age and physical condition, as tolerance to elevated blood levels varies. 6
• All probable sites of nerve injury must be comprehensively padded before surgery and assessed every 30 minutes throughout the procedure. 1

Postoperative Analgesia Strategy

• The supraclavicular block provides excellent postoperative analgesia for 12-18 hours, and regional catheter placement should be considered for extended postoperative analgesia. 1
• Multimodal analgesia must be planned, including scheduled acetaminophen and NSAIDs with age-adjusted and renal function-adjusted doses. 1
• Single-dose IV dexamethasone increases the analgesic duration of brachial plexus block and provides anti-emetic effects, with opioids reserved as rescue analgesia only. 3

Oncologic Considerations

• High-grade spindle cell sarcomas require aggressive surgical management with wide margins, and the anesthetic plan must not compromise surgical goals. 1
• Complete tumor resection is the cornerstone of curative treatment for high-grade bone sarcomas, as these tumors have metastasis rates of at least 50%. 7
• Regional anesthesia should not be performed before the patient has been evaluated by the specialized sarcoma multidisciplinary team, as this high-grade spindle cell sarcoma requires coordinated oncologic management. 3

Monitoring Requirements

• Resuscitative equipment, oxygen, and resuscitative drugs must be immediately available, as the safe use of local anesthetics depends on proper dosage, correct technique, and readiness for emergencies. 6
• Careful and constant monitoring of cardiovascular and respiratory vital signs and the patient's state of consciousness must be performed after each local anesthetic injection. 6
• Early warning signs of central nervous system toxicity include restlessness, anxiety, light-headedness, numbness and tingling of the mouth and lips, metallic taste, tinnitus, dizziness, and blurred vision. 6