Local Versus Intravenous (IV) Regional Anesthesia
Limited evidence supports the use of local anesthesia rather than intravenous regional anesthesia (Bier block) because it might offer longer pain relief after carpal tunnel release; no evidence meeting our inclusion criteria was found comparing general anesthesia to either regional or local anesthesia for carpal tunnel surgery.

Rationale
There were two moderate quality studies comparing local anesthesia to intravenous regional anesthesia. Nabhan (2011) studied 43 patients randomized to receive either local anesthesia or intravenous regional anesthesia using prilocaine. Three patients in the intravenous regional anesthesia group and one patient in the local anesthesia group required supplementation with additional local infiltration at the surgery site. The tourniquet was inflated longer in the intravenous regional anesthesia group but the operating time was the same in both groups. There were no other differences between the groups.
 
Sorensen et al (2013) randomized 38 patients to have endoscopic carpal tunnel release under either local anesthesia with ropivicaine or intravenous regional anesthesia with mepivicaine. The group treated with local anesthesia had less pain at the end of the procedure as well as two hours after surgery was completed although pain during the procedure was equal in the two groups.