Abstract ID: A35
Abstract Title: EVALUATION OF A NOVEL, ENCAPSULATED FORMULATION OF EPIDURAL MORPHINE FOR PAIN CONTROL AFTER ELECTIVE KNEE ARTHROPLASTY
Poster Type: Poster
ABSTRACT BODY
Introduction: Effective control of postoperative pain promotes mobilization that can facilitate earlier discharge after total knee arthroplasty. The use of epidural analgesia following total knee arthroplasty can provide good pain control and a shortened recovery time. This randomized, double-blind study compared the analgesic efficacy of DepoMorphine, a single-dose, long-acting (up to 48 hours), encapsulated formulation of epidural morphine, with intravenous (IV) patient-controlled analgesia (PCA) morphine following knee arthroplasty.
Methods: Before surgery, patients received epidural injection of DepoMorphine 20 mg (n=51) or 30 mg (n=61), or of sham epidural (IV PCA morphine group; n=56).
DepoMorphine: Patients received IV hydromorphone at first request for pain medication; after analgesia was adequate, patients had access to a placebo PCA pump. If pain control was still inadequate, patients received an increased placebo PCA and bolus IV hydromorphone injections.
IV PCA morphine: Patients received IV morphine at first request for pain medication; after analgesia was adequate, patients had access to an IV PCA morphine pump. If pain control was still inadequate, patients received an increased IV PCA morphine and a bolus IV placebo injection.
Assessments: Recalled pain intensity was the primary efficacy end point; at 4, 8, 12, 24, 30, 48 hours post-dose, patients were asked, "How much pain have you had since your last pain assessment?" This measure, as well as current pain intensity scores were rated on a 100-mm visual analog scale (VAS) 0–100). Additional assessments included postoperative opioid usage (IV morphine-mg equivalents), time to first postoperative opioid use, patient ratings of medication, and safety.
Results: Over the 48-hour period, mean (±SD) recalled pain intensity scores were lower with DepoMorphine 30 mg (32±19) than IV PCA morphine (39±19; P=.0286). DepoMorphine patients used less supplemental opioids during the 48-hour study period, as well as from 0 to 24 hours and 24 to 48 hours postoperatively (Table 1). All IV PCA morphine patients required supplemental opioids. However, DepoMorphine eliminated the need for supplemental opioids in some patients at 24 hours (20 mg: 14%; 30 mg: 28%; P=.0041 and P<.0001 vs IV PCA morphine, respectively) and 48 hours (20 mg: 8%; 30 mg: 16%; P=.0294 and P=.0019 vs IV PCA morphine, respectively). Despite lower use of postoperative opioids, DepoMorphine-treated patients had better mean VAS scores with activity and at rest compared with the IV PCA group (Figures 1 and 2). At 24 hours post-dose, significantly more patients had "good/very good" ratings of pain control in the DepoMorphine 20 mg (73%) and 30 mg (81%) groups compared with the IV PCA group (53%, P=.0328 and P=.0018 vs IV PCA morphine, respectively).
DepoMorphine was well tolerated, with a side-effect profile consistent with opioid therapy. The incidence of pruritus was higher in the pooled DepoMorphine (20+30 mg) group versus the IV PCA morphine group (57% vs 16%; P<.0001).
Conclusions: Following knee arthroplasty, DepoMorphine provided safe, effective analgesia over 48 hours.
This study was supported by SkyePharma, Inc.; abstract by Endo Pharmaceuticals with Accel Healthcare's editorial assistance.
ATTACHED FILES
A35_Table 1 and Figure captions.doc
A35_Fig 1.tif
A35_Fig 2.tif
Reg Anesth Pain Med 2004; 29(2):A35