Effects of catheter orifice configuration (triple-hole versus end-hole) in continuous infraclavicular brachial plexus block on analgesia after upper limb surgery.

BACKGROUND

The configuration of a nerve block catheter may affect the local anesthetic spread in epidural analgesia and continuous peripheral nerve blocks. This prospective and randomized study aims to compare the multi-orifice nerve block catheter with an end-hole catheter in ultrasound-guided continuous infraclavicular brachial plexus block (BPB) in terms of providing postoperative analgesia for the orthopedic upper limb surgery below the shoulder. The primary outcome measure was mean pain scores. Secondary outcome measures were the consumption of rescue analgesic and the amount of local anesthetics delivered by a Patient-Controlled Analgesia (PCA) device.

METHODS

A total of 58 adult patients who underwent orthopedic upper limb surgery below the shoulder were randomly assigned into two groups: group end-hole catheter (EHC) (n=31) and group multi-orifice catheter (MOC) (n=27). All patients received a single-shot infraclavicular BPB using 100 mg lidocaine 2% and 75 mg bupivacaine 0.5% administrated through a Tuohy needle. Then, a multi-orifice (triple-hole) nerve catheter was placed in the group MOC and an end-hole (one-hole) catheter in the group EHC at the same location. Bupivacaine 0.125% was infused through the catheters via PCA (infusion rate: 2 mlh-1, automated regular bolus: 5 mlh-1, patient-controlled bolus: 3 ml, lock-out time: 1 hour, 4 hours limit: 40 ml). Pain intensity was evaluated using a visual analogue scale (VAS).

RESULTS

Mean VAS scores were higher in group EHC than group MOC in the first postoperative day (p=0.001). Mean rescue analgesic consumption, the number of bolus demand on PCA, PCA bolus demand dose, and total PCA dose were higher in group EHC than group MOC during the first postoperative day (p<0.05).

CONCLUSION

It is concluded that the use of MHC is more effective than EHC for continuous infraclavicular brachial plexus blocks in providing postoperative pain relief during the first 24 hours.