Comparison of adjuvant therapy with midazolam, paracetamol, tramadol, or magnesium sulfate during intravenous regional anesthesia with ropivacaine: A randomized clinical trial.

Background: Intravenous (IV) regional anesthesia is an easy, safe, reliable, and efficient option for inducing anesthesia during surgeries but with tourniquet-related pain. This study aimed to evaluate midazolam, paracetamol, tramadol, and magnesium sulfate administration as adjuvants with ropivacaine on pain relief and hemodynamic changes in IV regional anesthesia.

Methods: A randomized, double-blind, placebo-controlled trial was conducted in subjects undergoing forearm surgery with IV regional anesthesia. The block randomization method was used to assign eligible participants to each of five study groups. Hemodynamic parameters were assessed before applying the tourniquet, at prespecified time points (5, 10, 15, and 20 min), then and every subsequent 10 min until surgery completion. A Visual Analog Scale was used to assess pain severity at baseline followed by every 15 min until completion of the surgery, and after tourniquet deflation every 30 min to 2 h, and at 6, 12, and 24 h postoperative. Data were analyzed using Chi-square and analysis of variance with repeated data testing.

Results: The shortest onset and the longest duration of sensory block were observed in the tramadol group and the shortest onset of motor block in the midazolam group (P < 0.001). Pain score was estimated to be significantly lower in the tramadol group at the time of tourniquet application and release, and 15 min to 12 h after tourniquet release (P < 0.05). In addition, the lowest dose of pethidine consumption was observed in the tramadol group (P < 0.001).

Conclusion: Tramadol appeared to be able to effectively relieve pain, shorten the onset of sensory block, prolong the duration of sensory block, and achieve the lowest consumption of pethidine.