Dexmedetomidine improves the outcome of a bupivacaine Brachial plexus axillary block : a prospective comparative study

Abstract EN

Objectives To evaluate the feasibility and outcome of upper limb orthopedic surgery under an axillary brachial plexus block using either bupivacaine alone or bupivacaine combined with dexmedetomidine (DEX).

Patients were divided into two equal groups (n = 25).

The patients in group B received 40 ml of 0.25% bupivacaine plus 1ml normal saline only and the patients in group D received a mixture of 40 ml of 0.25% bupivacaine plus 1ml DEX (100 mcg).

The four main nerves in the axilla (musculocutaneus, radial, median, and ulnar) were identified using neural stimulation by a 1mA current by a single injection.

Sensory block was assessed at 10-min intervals with an ice cube testing the skin areas supplied by the identified nerves, and the motor block was evaluated once at the end of the 30-min period.

Block performance data, duration of sensory and motor block, duration of analgesia, and pain severity at the time of request of rescue analgesia were rated using a 10-point visual analog scale (VAS).

Patient comfort during the anesthetic procedure was evaluated on a VAS 0–10 scale and surgeon’s satisfaction in terms of intraoperative anesthesia and analgesia and postoperative analgesia.

Results Axillary block yielded an overall success rate of 100%.

There was a nonsignificant difference between both groups in terms of the frequency of complete block, nerves that escaped block, block performance time, or motor block duration.

However, the latency time was significantly shorter and the duration of sensory block was significantly longer in group D compared with group B.

The mean VAS pain score was significantly lower with a significantly longer duration of postoperative analgesia in group D compared with group B.

Moreover, 16 patients did not request rescue analgesia until discharge and 29 patients requested it only once, with a significant difference in favor of group D.

The block performance in group D was highly satisfactory for both the patients and the surgical team, with a significantly higher mean satisfaction score compared with group B.

DEX added to bupivacaine for an axillary brachial plexus block shortened the onset time and prolonged the duration of the block and the duration of postoperative analgesia, and allowed upper limb orthopedic surgery to be managed as an outpatient procedure.