Perineural Versus Systemic Dexamethasone in Front-Foot Surgery Under Ankle Block: A Randomized Double-Blind Study

Area of Science:

• Anesthesiology
• Pharmacology
• Orthopedic Surgery

Background:

• Dexamethasone is a commonly used adjuvant to prolong local anesthetic effects.
• The optimal administration route for dexamethasone in ankle blocks remains under investigation.
• Metatarsal osteotomy is a surgical procedure often requiring effective postoperative pain management.

Purpose of the Study:

• To compare the efficacy of perineural versus systemic dexamethasone as an adjuvant to ropivacaine in single-shot ankle blocks.
• To determine if perineural dexamethasone offers superior pain relief compared to intravenous administration after metatarsal osteotomy.
• To evaluate the duration of analgesia and rescue analgesic consumption in patients undergoing metatarsal osteotomy.

Main Methods:

• A prospective, double-blind, randomized study involving 100 patients undergoing metatarsal osteotomy.
• Patients received either perineural dexamethasone (4 mg) with systemic saline or intravenous dexamethasone (10 mg) with perineural saline, alongside ropivacaine ankle block.
• The primary endpoint was the duration of analgesia, measured by the time to first tramadol rescue analgesia.

Main Results:

• The duration of analgesia was similar between the intravenous dexamethasone (23.2 hours) and perineural dexamethasone (19 hours) groups (P = 0.4).
• Tramadol consumption in the first 48 hours was comparable between the groups (P = 0.59).
• Nausea or vomiting occurred in 8% of the intravenous dexamethasone group versus 24% of the perineural dexamethasone group (P = 0.03).

Conclusions:

• Perineural and systemic dexamethasone administration are equivalent for postoperative pain relief when used as an adjuvant to ropivacaine ankle block in front-foot surgery.
• Neither administration route demonstrated superiority in prolonging analgesia duration.
• Intravenous dexamethasone was associated with a lower incidence of nausea and vomiting.