WALANT for Smaller Hand Procedures — Almost There?

What’s the Claim?

A study of more than 650 patients undergoing either carpal tunnal release (CTR) or trigger finger release that compared “WALANT” surgery (wide-awake, local anesthetic, no tourniquet) to surgery with monitored anesthesia care (MAC, which included a tourniquet set to 250 mmHg and gentle sedation) found no differences in the risk of infection between the approaches. The setting used in both anesthetic approaches was a minor procedure room with what the authors described as “full sterility.” Follow-up occurred for all patients at 4 weeks; infections after that seem unlikely. About 2% of the patients who underwent surgery with MAC developed infections after CTR, and none developed infections after CTR using WALANT. There were no infections after trigger finger release in either group.

How’s It Stack Up?

The conversation about the safety of WALANT surgery is heating up. Concerns about infection have been more anecdotal than data-driven, and some concerns about contraindications to epinepherine injections (which are part of WALANT) in patients with certain cardiac, vascular, and hematologic conditions also have been raised. But COVID resulted in a surge of interest in WALANT because of resource constraints, and WALANT certainly has practical appeal in terms of lowering costs of delivering care in a surgicenter. The latest wave of studies on WALANT seem rather enthusiastic about it, but none has been large enough to be completely convincing on the main concern — infection. That will require a large-database study, most likely.

What’s Our Take?

Cautious optimism. Proving safety is difficult — it takes many more patients than the current study had. The authors claimed 80% power to detect a between-group difference in infection, but reading the fine print clarifies that the difference would have to be enormous: 6% versus 1%. I think we can agree that a sixfold increase in infection risk would be unacceptable, but so would a twofold increase, and our sample-size calculation found that a study of only 650 patients would very likely have missed a doubling of infection risk, had it been present. That said, there were no infections at all in the WALANT group, which is reassuring, and about 2% in the MAC group. Since WALANT is not likely to protect patients from infection, this difference is either a data point in the cloud of the 95% CI or a function of patient selection — perhaps choosing healthier patients for WALANT. We looked around for a convincingly large series on this topic and did not find one. In better news, there are several studies like this one, and all seem somewhat reassuring on the topic of infection. WALANT is unlikely to be for all patients anyway, and what’s known about it so far suggests it’s reasonable to try in patients who are willing, and in whom you have no concerns about using epinepherine.

Source

Rellán I, Bronenberg Victorica P, Fortuna Figueira SVK, Donndorff AG, De Carli P, Boretto JG. What Is the Infection Rate of Carpal Tunnel Syndrome and Trigger Finger Release Performed Under Wide-Awake Anesthesia? Hand (N Y). 2023;18:198-202.