Abstract

Objective: in Chile, the availability of certain presentations of local anesthetics has been compromised recently. In a recent study, our group demonstrated that bupivacaine 0,5% is like lidocaine 2% in terms of cutaneous block latency and injection pain upon injection when used for subcutaneous infiltration. In the present study, implementing a similar methodology, we compared bupivacaine 0,5% with bupivacaine 0,25% and bupivacaine 0,5% with levobupivacaine 0,5% in subcutaneous infiltrations. Materials and Methods: Two series of ten volunteers were studied sequentially. In the first series, each volunteer was injected with 3 ml of levobupivacaine 0,5% or bupivacaine 0,25% in each forearm. According to the results of this series, in the second series, it was decided to compare bupivacaine 0,5% with levobupivacaine 0,5%, following the same methodology. Puncture pain, injection pain, latency to pinprick and cold sensory block, and duration of sensory blockade were evaluated. Results: In the first series of patients, bupivacaine 0,25% presented a significantly longer latency than bupivacaine 0,5%, 60[10-105]seconds vs. 90[30-180]seconds, respectively, but without clinical or statistical significant differences in terms of pain upon infiltration. Subsequently, bupivacaine 0,5% and levobupivacaine 0,5% showed no differences in block latency, 45[30-150]seconds vs. 60[30-60]seconds, respectively, although with a statistically significant increased pain upon infiltration with levobupivacaine. In all study groups, the skin block lasted more than 8 hours. Conclusion: Bupivacaine 0,5% and levobupivacaine 0,5% represent valid alternatives for a “wheal” type subcutaneous infiltration providing short and similar latency times. Future studies should determine whether these findings in skin block are consistent with analgesia in procedures using subcutaneous wheals with these drugs.