The Effect of Buffered Lidocaine in Local Anesthesia: A Prospective, Randomized, Double-Blind Study

PurposeOpen carpal tunnel decompression under local anesthesia is routinely done by many surgeons. However, patients complain of pain during the injection of local anesthesia. This prospective, double-blind, randomized study was to compare the pain visual analog scale (VAS) scores of local anesthesia using lidocaine with and without sodium bicarbonate in patients with bilateral carpal tunnel syndrome.MethodsTwenty-five patients underwent bilateral simultaneous carpal tunnel decompression. All had topical anesthetic cream applied on the palm and wrist before the lidocaine block. In a randomized manner, half of the hands were blocked with nonbuffered lidocaine and half were blocked with buffered lidocaine. Pain was evaluated on a VAS score.ResultsThe mean pain VAS score in the hand with buffered lidocaine was 4.6 ± 1.5 and 6.5 ± 1.5 for the hand with nonbuffered lidocaine. After adjustment for individual threshold of the pain, the mean pain VAS score changed into 4.6 ± 1.3 with buffered lidocaine and 6.6 ± 1.7 without buffered lidocaine.ConclusionsIn open carpal tunnel surgery, the use of buffered lidocaine for local anesthesia reduces the anesthetic pain effectively.Type of study/level of evidenceTherapeutic I.