Purpose: To describes a technique of indwelling interscalene catheter placement and to evaluate its complications.
Methods: One hundred and twenty patients undergoing major shoulder surgery received interscalene nerve block (ISNB) and were studied in three groups. Group 1 ISNB using Winnie's technique; group 2 by Winnie's technique with nerve stimulator and group 3 by epidural needle and catheter technique with nerve stimulator. All patients received 20 mL bupivacaine 0.5% and group 3 patients received an additional bupivacaine 0.25% infusion. Diaphragmatic movements were measured sonographically on emergence from anesthesia. Complications were noted. A visual analogue scale (0-10) was used to assess pain four hours postoperatively.
Results: Mean ipsilateral diaphragmatic movements were 4+/-8, 14+/-11 and 18+/-8 mm (mean +/- SD) in groups 1, 2 and 3 respectively. This was less than contralateral movements in all three groups (P < 0.05). None of the patients in groups 2 and 3 reported postoperative pain. The block failed in 10% of group 1 patients. Complete ipsilateral phrenic nerve block occurred in 85% of the patients in group 1, 35% of group 2 and 20% of group 3 (P < 0.05). Ipsilateral recurrent laryngeal nerve paralysis occurred in 20% of the patients in group 1, 5% of group 2 and in none of the patients in group 3 (P < 0.05). Horner's syndrome was noted in group 1 (30%), group 2 (12%) but not in group 3. None of the catheters in group 3 patients dislodged after an average use of 2.8+/-2.1 days.
Conclusions: Indwelling catheter placement into the brachial plexus sheath as described in this communication was effective and associated with few complications.