Conditions: Post Surgical Pain
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 89
Healthy volunteers: no

Brief summary:
When used in conjunction with a local anesthetic, dexamethasone may prolong both the sensory and motor effects of high supraclavicular brachial plexus nerve block (SBP) in arthroscopic shoulder surgery. This study seeks to determine if there is a relationship between the duration of sensory and motor blockade in supraclavicular brachial plexus nerve blocks (SBP) when combined with increasing doses of dexamethasone.

Detailed description:
The exact mechanism of dexamethasone on peripheral nerve block is unclear. The current theory is that the effect is not dose related, while only 4mg and 8mg doses were studied. Our hypothesis is that the dose differences at 1mg, 2mg, or 4mg, does not have significant effect on the duration of analgesia. Therefore, we are not considering any patients to receive suboptimal dosing of preservative free dexamethasone in this study.

Arms:
arm 1: Bupivacaine 0.25% mixed with 1ml normal saline (placebo/control group) arm 2: Bupivacaine 0.25% mixed with 1mg preservative free dexamethasone (1ml) arm 3: Bupivacaine 0.25% mixed with 2mg preservative free dexamethasone (1ml) arm 4: Bupivacaine 0.25% mixed with 4mg preservative free dexamethasone (1ml

Interventions: intervention 1: Bupivacaine 0.25% intervention 2: Dexamethasone intervention 3: normal saline
Intervention descriptions: intervention 1: None intervention 2: None intervention 3: placebo

Protocol document: