Regional anesthesia and pain medicine
-
Despite its popularity, ultrasound (US)-guided regional anesthesiology is associated with significant limitations. The latter can be attributed to either the US machine (ie, decreased ability to insonate deep neural structures, as well as the thoracic spine) or the operator. Shortcomings associated with the operator can be explained by errors in perception (ie, ambiguous criteria for needle/catheter tip-to-nerve proximity and subparaneural local anesthetic injection) or interpretation. ⋯ For continuous nerve blocks, combined US-neurostimulation may provide an objective end point (ie, an evoked motor response) for neural proximity and subparaneural positioning of the catheter tip. Finally, the solution to the plethora of nonvalidated US-guided blocks is both elegant and simple. New nerve blocks should answer a specific clinical need, and their first descriptions should take the form of an adequately powered, observer-blinded, randomized comparison against the established standard of care or, at the very least, a large case series (eg, a Brief Technical Report).
-
Reg Anesth Pain Med · Sep 2017
Case ReportsNeuralgic Amyotrophy Attributed Incorrectly to Block-Related Injury: Understanding Errors in Clinical Reasoning.
We report a case of misdiagnosed neuralgic amyotrophy (brachial plexus neuritis, Parsonage-Turner syndrome). Our primary objective is to review the scientific basis for errors in clinical reasoning. ⋯ Cognitive bias may lead to errors in clinical reasoning and consequent misdiagnosis. Temporal proximity may falsely implicate regional anesthesia as the causative agent.
-
Reg Anesth Pain Med · Sep 2017
Observational StudySerum Bupivacaine Concentration After Periarticular Injection With a Mixture of Liposomal Bupivacaine and Bupivacaine HCl During Total Knee Arthroplasty.
A relatively new technique to reduce postoperative pain for total knee arthroplasty is to inject a mixture of 266 mg of liposomal bupivacaine and 125 mg of 0.25% bupivacaine HCl with epinephrine 1:300,000 around the knee joint at the time of surgery. Currently, no publications report serum bupivacaine concentrations over time after periarticular injection of liposomal mixed with free bupivacaine. This information is important to ensure safe serum bupivacaine concentrations are maintained especially when considering supplemental or rescue peripheral nerve blocks. ⋯ Total serum concentrations of bupivacaine after periarticular administration of liposomal bupivacaine mixed with bupivacaine HCl remained below the described toxicity threshold (2.5 μg/mL) within the first 48 hours, and no patients demonstrated signs or symptoms of toxicity. However, peak serum concentration time was not achieved within the 48-hour interval. Additional studies are needed to describe the course of serum bupivacaine levels after 48 hours and to ascertain the risk of toxicity when combining this method of periarticular injection with peripheral nerve blocks.