Continuous Regional Anesthesia: A Practical Review of Perineural and Fascial Plane Catheters, Clinical Evidence, and Troubleshooting

Continuous regional anesthesia (CRA) can extend postoperative analgesia beyond the duration of single-injection blocks and may reduce reliance on systemic opioids. The expanding use of perineural and fascial plane catheters has broadened the clinical applications of catheter-based regional analgesia across a wide range of surgical settings. However, successful CRA requires appropriate patient and catheter selection, accurate catheter placement, effective local anesthetic delivery, securement, monitoring, and timely recognition of catheter failure or complications. This review provides a practical overview of contemporary perineural and fascial plane catheter techniques and summarizes the available clinical evidence for their use in upper- and lower-limb, thoracic, cardiac, and abdominal surgery. Catheter-through-needle and catheter-over-needle systems, catheter tip configurations, pumps and delivery systems, and continuous, programmed intermittent, and patient-controlled infusion strategies are discussed. Practical aspects of ultrasound-guided catheter insertion, catheter-tip confirmation, fixation, and prevention of catheter migration are also reviewed. Current evidence suggests that continuous catheter techniques can improve postoperative analgesia and reduce opioid requirements in selected procedures, although the magnitude and consistency of benefit vary according to the surgical population, anatomical target, catheter technique, and comparator. Local anesthetic selection, concentration, infusion rate, cumulative dose, catheter location, and patient-specific risk factors should be considered to balance analgesic efficacy against motor impairment and local anesthetic systemic toxicity. Particular attention is required in patients with increased susceptibility to toxicity and when bilateral or multiple catheters are used. Catheter failure may result from inadequate dosing or spread, catheter malposition or migration, mechanical dysfunction, or pain outside the expected block distribution. A structured approach incorporating clinical assessment, catheter-site inspection, delivery-system evaluation, and ultrasound-guided assessment of injectate spread may identify reversible causes of inadequate analgesia. A stepwise troubleshooting algorithm is presented to guide catheter optimization, rescue interventions, replacement, or removal. In conclusion, effective CRA requires integration of appropriate catheter technology, individualized dosing, secure fixation, systematic monitoring, and structured troubleshooting.