Automated Boluses and Delayed-Start Timers Prolong Perineural Local Anesthetic Infusions and Analgesia Following Ankle and Wrist Orthopedic Surgery: A Case-Control Series

BACKGROUND: Continuous peripheral nerve blocks can be administered as continuous infusion, patient-controlled boluses, automated boluses, or a combination of these modalities. MATERIAL/METHODS: Ten patients undergoing either ankle (5) or distal radius (5) open reduction and internal fixation received single-injection ropivacaine sciatic nerve block or infraclavicular brachial plexus block and catheter. Infusion pumps were set to begin administering additional ropivacaine 6 h following the initial block as automated boluses supplemented with patient-controlled boluses. RESULTS: Patients had similar pain scores when compared to previously published controls; however, local anesthetic consumption was lower in the patients, resulting in increased infusion and analgesia duration by 1 or more days in each group. CONCLUSIONS: For infraclavicular and popliteal sciatic catheters, automated boluses may provide a longer duration of analgesia than continuous infusions following painful hand and ankle surgeries, respectively.