Is outpatient continuous regional analgesia more effective and equally safe than single-shot peripheral nerve blocks after ambulatory orthopedic surgery?

Introduction: Continuous regional analgesia is an established technique for effective postoperative pain treatment, particularly after orthopedic surgical procedures. Even if it has been increasingly applied to the outpatient setting as well, many anesthesiologists are still reluctant to discharge patients with a perineural catheter in place. Aim of this review was to clarify the evidences about safety and effectiveness of outpatient continuous peripheral nerve blocks.

Evidence Acquisition: A systematic review of all prospective, randomized, double-blinded, placebo-controlled trials of the last 20 years on outpatient continuous peripheral nerve blocks after ambulatory orthopedic surgery was performed, using both PubMed and OVID databases were. Study quality was assessed using the modified Jadad Scale. Primary outcomes were pain at 24 and 48 hours and morphine consumption.

Evidence Synthesis: Five studies matched the inclusion criteria and were considered of good quality to be included in the review process. All these studies consistently showed a better pain control both at rest and during movement within the first postoperative day, leading to a reduced opioid consumption in patients treated with outpatient continuous regional analgesia. However, only three studies showed these advantages to be sustained longer than the first 24 hours postoperatively. No severe complications were reported.

Conclusions: High-quality evidences about outpatient regional analgesia are scarce. Considering the advantages of continuous peripheral nerve blocks in the inpatient setting more prospective studies assessing also functional recovery are needed to further implement these techniques in the ambulatory setting.