Peripheral nerve blocks (PNBs) are increasingly used as a component of multimodal
analgesia and may be administered as a single injection (sPNB) or continuous infusion via a perineural
catheter (cPNB). We undertook a qualitative review focusing on sPNB and cPNB with regard to benefits, risks, and opportunities for optimizing patient care. Meta-analyses of randomized controlled trials have shown superior
pain control and reductions in
opioid consumption in patients receiving PNB compared with those receiving intravenous
opioids in a variety of upper and lower extremity
surgical procedures. cPNB has also been associated with a reduction in time to discharge readiness compared with sPNB. Risks of PNB, regardless of technique or block location, include vascular
puncture and
bleeding, nerve damage, and
local anesthetic systemic toxicity. Site-specific complications include quadriceps weakness in patients receiving femoral nerve block, and pleural
puncture or neuraxial blockade in patients receiving interscalene block. The major limitation of sPNB is the short (12-24 hours) duration of action. cPNB may be complicated by catheter obstruction, migration, and leakage of
local anesthetic as well as accidental removal of
catheters. Potential infectious complications of
catheters, although rare, include local
inflammation and
infection. Other considerations for ambulatory cPNB include appropriate patient selection, education, and need for 24/7 availability of a health care provider to address any complications. The ideal PNB technique would have a duration of action that is sufficiently long to address the most intense period of
postsurgical pain; should be associated with minimal risk of
infection, neurologic complications,
bleeding, and
local anesthetic systemic toxicity; and should be easy to perform, convenient for patients, and easy to manage in the postoperative period.