Abstract ID: A09

Abstract Title: Effect of Posterior Lumbar Plexus Perineural Local Anesthetic Infusion on Postoperative Functional Ability Following Total Hip Arthroplasty

Poster Type: Discussion


ABSTRACT BODY

Introduction: Total hip arthroplasty (THA) results in significant functional impairment in the immediate postoperative period, primarily because of pain experienced with joint motion. Singelyn, et al, provided evidence that a perineural infusion via a “lumbar plexus” catheter following THA provides superior analgesia to IV opioids (1). Additional investigations have examined different aspects of this technique, such as the optimal insertion technique and infusion delivery regimen (2,3). However, currently no data reflect the potential effect of perineural infusion on postoperative functional mobility following THA. If perineural infusion improves patients’ postoperative ambulatory ability, this analgesic technique could increase patient independence, optimize postoperative rehabilitation, decrease the risk of thromboembolism, allow for earlier hospital discharge, and improve ultimate joint function (4). Therefore, we undertook this prospective pilot study to investigate the relationship between perineural infusion and ambulation ability following THA, and to help determine if a larger study is warranted.

Methods: Preoperatively, after IRB approval and informed consent, patients (n=10) had a psoas compartment catheter placed using a nerve stimulator and 10-15 cm, 18g insulated needle (Contiplex, B. Braun Medical, Bethlehem, PA, USA) as previously described (5). Intraoperatively, patients received a GA with sevoflurane/N2O/O2. Postoperatively, patients received ropivacaine 0.2% (basal 8 mL/h, bolus 4 mL, lockout 30 min) via the catheter through postoperative day 4 using a portable electronic infusion pump (Pain Pump II, Stryker Instruments, Kalamazoo, MI, USA). Patients received oral and/or IV opioids for pain uncontrolled with a ropivacaine bolus. Maximum ambulatory distance was measured during twice-daily physical therapy sessions. Pain scores were recorded using a 0-10 numeric rating pain scale (NRS; 0 = no pain, 10=worst imaginable pain).

Results: Figs. 1–2 (median values). All patients were able to make independent bed-to-bathroom transfers the day after surgery. No patient required IV opioids following PACU discharge (Table 1, median values).

Conclusions: Although data involving rehabilitation in the immediate postoperative period following THA has not been previously published, experience at our institution suggests that for patients receiving exclusively opioids for analgesia, the maximum ambulatory distance is 10-20 m in the first two days following surgery, and is accompanied by significant pain during mobilization. In this context, the data from this pilot study suggests that following THA, a posterior lumbar plexus perineural ropivacaine infusion is associated with an improvement in patients’ functional ability and analgesia during mobilization. However, this assertion requires confirmation with a randomized, double-blind, placebo-controlled trial.

References: (1) J Clin Anesth’99;11:550. (2) A&A’02;94:1606. (3) A&A’01;92:455. (4) Clin Orthop’03:193. (5) Anesthesiology’01;95:A38.

ATTACHED FILES

A09_Table 1.doc

A09_Table 2.doc



Reg Anesth Pain Med 2004; 29(2):A09