Single-Injection Distal Upper-Limb Anesthesia Provides appropriate Postoperative Pain Relief, Suggests Study

Traditional upper-limb anesthesia often carries risks such as pneumothorax from deep needles, or it requires multiple injections. To overcome these limitations, Dr. Revathi Nair and her team detailed a novel, superficial subdeltoid approach to provide a simpler and safer alternative.

Therefore, the retrospective study evaluated six adult patients with distal arm injuries who received a targeted 15 mL anesthetic injection of bupivacaine and dexamethasone. Excluding individuals with specific contraindications, the researchers primarily tracked the onset of surgical anesthesia, tourniquet tolerance, and postoperative pain-free duration.

Key Clinical Findings of the Study Includes:

• Complete Anesthetic Success: All six evaluated patients achieved profound anesthesia across the entire affected limb with a single injection, successfully avoiding the multiple needle passes conventionally required in standard axillary blocks.

• Consistent Tourniquet Tolerance: The proximal application of the block yielded comprehensive motor and sensory coverage before nerve divergence, thereby enabling universal tourniquet tolerance without the requirement for additional sedation.

• Extended Analgesic Duration: Patients experienced a highly substantial postoperative recovery window, with pain assessments revealing an average pain-free duration of exactly 17.3 hours.

• Exceptional Safety Profile: Procedural execution remained highly secure, demonstrating a complete absence of local anesthetic systemic toxicity (LAST), vascular punctures, or the pneumothorax risks generally associated with steeper infraclavicular approaches.

• Favourable Anatomical Validation: Cadaveric dissection firmly corroborated the sonographic observations, confirming that terminal nerves cluster into a proximal "nerve funnel" around the axillary artery at a highly accessible, superficial depth of 1.5 to 2.5 cm.

The results suggest that the ultrasound-guided subdeltoid brachial plexus block is a highly practical and clinically reliable method for managing upper-limb anesthesia, successfully providing extensive pain relief using a single targeted 15 mL injection.

Thus, the study concludes for emergency department and trauma clinicians, this relatively superficial technique might present a streamlined and anatomically straightforward option that facilitates rapid execution with minimal patient repositioning in high-acuity settings.

Although the current findings are inherently constrained by a limited sample size, a retrospective design, and reliance on a single experienced operator, they gently point toward a need for larger, multicenter prospective trials to robustly validate the technique's long-term safety, reproducibility, and comparative efficacy.

Reference

Nair R, Goyal A, Jain K, Aggarwal A. Subdeltoid ultrasound-guided brachial plexus block: A technical description with anatomical correlation and a preliminary case series. Indian J Anaesth 2026;70:857-60.