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Background and Aims Continuous peripheral nerve block (CPNB) is an effective technique for acute pain control with a low incidence of serious adverse events. However, failure is a recognised complication and not uncommon. This audit aims to establish the incidence of primary (inadequate insertion) and secondary failure (catheter displacement, disconnection, occlusion, leakage) at our institution.

Methods All patients receiving CPNB over a 3-month period (August to October 2022) at St George’s Hospital, UK, were identified. Information on their management was collected retrospectively from their electronic hospital records.

Results 120 episodes of CPNB in 103 patients were analysed. 65% (n=77) were chest wall catheters: 32% (n=38) paravertebral (PV); 21% (n=25) erector spinae plane (ESP) and 12% (n=14) serratus anterior plane (SAP). 27% (n=32) were sciatic. The remaining 10% (n=11) included intrapleural, femoral, rectus sheath and transversus abdominal plane (TAP) catheters. Mean catheter duration was 3.9 ± 2.3 days. Overall, 67% (n=80) remained until no longer clinically needed. However, 30% (n=36) were removed for other reasons. The majority of these, 75% (n=27), suffered problems of displacement, disconnection, occlusion or leakage (i.e. secondary failure). 14% (n=5) were removed for not being effective (primary failure); 6% (n=2) because of infection and 6% (n=2) for other reasons.

Conclusions The overall incidence of secondary, and potentially preventable, CPNB failure in our institution is 23% (n=27), which results in a significant burden of work for the treating clinicians and sub-optimal pain management for these patients. This is prompting renewed scrutiny of our processes, especially regarding the ongoing management of CPNB.