DOS BULLETIN - Dansk Ortopædisk Selskab

2010-378_DOS nr. 3 2010 29/09/10 10:08 Side 137
Local infiltration analgesia for acute pain relief in hip
arthroplasty: Do we need it? A randomized, doubleblind,
placebo-controlled trial in 120 patients
Troels H. Lunn, Henrik Husted, Søren Solgaard Kristian Stahl Otte,
Anne Grete Kjersgaard, Henrik Kehlet
Arthroplasty Section, Department of Orthopaedics, Hvidovre Hospital,
Denmark; Hip Clinic, Hørsholm Hospital, Department of
Orthopaedics, Hillerød Hospital, Denmark;
Section for Surgical Pathophysiology, Rigshospitalet
Background: High-volume local infiltration analgesia (LIA) is widely applied
as part of a multimodal pain management strategy in total hip arthroplasty
(THA). However, methodological problems hinder exact interpretation of previous
trials, and the evidence for LIA in THA is questionable.
Purpose: We aimed to evaluate if intraoperative high-volume LIA, in addition
to a multimodal oral analgesic regime, would further reduce acute postoperative
pain after THA.
Methods: Ethics committee approval was granted. One hundred twenty patients
scheduled for unilateral, primary THA using spinal anaesthesia were included
in this randomized, double-blind, placebo- controlled trial receiving high-volume
(150 ml) infiltration with ropivacaine 0.2% with epinephrine (10µg ml-1)
or saline 0.9% in the wound intraoperatively. The multimodal oral analgesic
regime was instituted preoperatively and consisted of slow release acetaminophen
2g, celecoxib 400mg and gabapentin 600mg. Rescue analgesic consisted
of oral oxycodone. The primary endpoint was pain during walking (5 meters) up
to 8h after surgery. Secondary endpoints were pain at rest, pain upon 45° flexion
of the hip with straight leg and cumulated consumption of oxycodone. Pain
was assessed repeatedly the first 8h after surgery using the 100mm visual analog
scale. Non-parametric statistics with post hoc Bonferroni correction for
repeated measures was applied.
Findings: Pain scores were low for all pain assessments (median around 20
mm) and did not differ between the ropivacaine and the placebo group (p>0.05).
Consumption of rescue oxycodone and summarized (added) pain scores (2-8h)
did not differ between groups (p>0.05).
Conclusion: This study demonstrated that a multimodal oral analgesic regime
with gabapentin, celecoxib and acetaminophen caused low acute postoperative
pain following THA, and LIA did not further improve analgesia. Positive results
reported in previous trials may be due to a systemic analgesic effect of NSAID
added to the LIA-mixture (but not in the control group). We cannot rule out that
LIA may have an analgesic effect with a less comprehensive oral regime or in
selected patients (high pain responders).
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