A comparison of stimulation patterns in axillary block: part 2.
OBJECTIVE
Radial plus musculocutaneous nerve stimulation may have a predominant role in the success of an axillary block, producing more extensive anesthesia of the upper limb than median plus musculocutaneous nerve stimulation. However, no comparison has been made with ulnar plus musculocutaneous nerve stimulation. We compared the extent of both sensory and motor block after ulnar plus musculocutaneous nerve stimulation or radial plus musculocutaneous nerve stimulation.


METHODS
Sixty patients were randomly assigned to receive an axillary block using either radial plus musculocutaneous or ulnar plus musculocutaneous nerve stimulation with 40 mL plain 1.5% mepivacaine. Patients were assessed for sensory block by the pinprick method at 5 and 20 minutes.


RESULTS
No statistically significant differences were found in the rates of anesthesia at 20 minutes in the cutaneous nerve distributions of the upper limb between radial plus musculocutaneous and ulnar plus musculocutaneous nerve stimulation except for the following nerves: radial (90% and 63.3%, respectively), medial cutaneous of the forearm (83.3% and 100%, respectively), and medial cutaneous of the arm (73.3% and 93.3%, respectively). Global sensory score (minimum: 0; maximum: 12 points) at 20 minutes was significantly higher after radial plus musculocutaneous than after ulnar plus musculocutaneous nerve stimulation: 12 (11-13) and 11 (10-12), respectively. The rates of median nerve blockade were 50% and 53%, respectively.


CONCLUSIONS
Radial plus musculocutaneous nerve stimulation produced more extensive anesthesia of the upper limb than did ulnar plus musculocutaneous nerve stimulation. However, there is not an optimal combination of 2 responses in axillary brachial plexus block.
Rodríguez
Jaime
J
Department of Anesthesiology, Hospital Clínico, Universitario de Santiago, Santiago de Compostela, Spain. jaime_rodríguez_garcia@yahoo.es
Taboada
Manuel
M
Valiño
Cristina
C
Bárcena
María
M
Alvarez
Julián
J
D000779:Anesthetics, Local / Q000008:administration & dosage / Q000494:pharmacology; D001365:Axilla / Q000294:innervation* / Q000601:surgery; D005260:Female; D006801:Humans; D007267:Injections; D008297:Male; D008619:Mepivacaine / Q000008:administration & dosage / Q000494:pharmacology; D008875:Middle Aged; D009046:Motor Neurons / Q000187:drug effects; D009138:Musculocutaneous Nerve / Q000187:drug effects; D009407:Nerve Block / Q000379:methods; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects; D011826:Radial Nerve / Q000187:drug effects; D004561:Transcutaneous Electric Nerve Stimulation; D014459:Ulnar Nerve / Q000187:drug effects
D000779:Anesthetics, Local; D008619:Mepivacaine