1. EREM Reduces Reliance on Parenteral Opioids and Pump Technology after Total Joint Arthroplasty Kishor Gandhi MD MPH, Kathleen Colfer MSN, RN-BC, Robert F Olszewski, Jr, BS, Steven Schaefer, BS, and Eugene Viscusi MD

2. Introduction:  Pain control is an important source of morbidity in the hospital setting  Effective control of postoperative pain reduce 1-4 :  Incidences of myocardial infarctions  Deep venous thrombosis  Pulmonary embolisms  Current treatment of pain control includes:  Epidural analgesia with continuous catheters  PCA’s that supply parenteral opioids upon patient needs 1 Liu et al Anesthesia and Analgesia 1995 82:1474-1506 2 Wu et al Anesthesia and Analgesia 2000 91:1232-1242 3 Beattle et al Anesthesia and Analgesia 2001 93: 853-858 4 Rodgers et al BMJ 2000 321:1493-1496

3. Introduction (Cont’d):  Extended-release Epidural Morphine (EREM) [DepoDur TM ]:  microscopic spherical particles with internal aqueous chambers that contain morphine  After a single injection in epidural space before surgery, the chambers degrade at physiologic conditions to release morphine slowly up to 48 hours  The delayed release of morphine provides adequate pain relief for patients until they are transitioned to oral analgesics  The purpose of this analysis:  Retrospectively evaluate post-operative pain and opioid requirements in patients who received EREM compared to controls with traditional modes of therapy

4. Methods:  Retrospective IRB approved analysis includes random selection of patients who underwent TJA from January-July 2007  Patients were chosen based on different postoperative analgesic modalities:  Total Hip Arthroplasty  EREM 7.5 mg  EREM 10 mg  Combined intrathecal Morphine PF with Fentanyl IV-PCA  Fentanyl IV-PCA  Total Knee Arthroplasty  EREM 10 mg  EREM 12.5 mg  Indwelling epidural catheter with 0.2% Ropivacaine and fentanyl IV-PCA  Single Injection femoral nerve block and fentanyl IV- PCA

5. Methods (cont’d):  Patient information was extracted from medical records and gathered in a database  Information included:  post-operative pain measured at multiple times during POD 0, 1, & 2;  need for oral opioids, parenteral opioids, or IV- PCA requirements for postoperative pain control  Primary outcomes measured include average pain score of patients on POD 0, 1, & 2 with different modes of post-operative pain control after TJA  Further analysis includes the proportion of patients who needed oral and parenteral opioids during postoperative day 0, 1, & 2  All opioids (oral and parenteral) converted to parenteral morphine (IV) equivalence  Statistical analysis was done with ANOVA with alpha=005 with two tailed distribution to compare means Bonferoni adjustments were conducted to allow for multiple comparisons between groups

6. Results: Figure 1: Post-operative opioid requirements in patients after Total Hip Arthroplasty Average Morphine Requirements (mg) Post-operative Pain Control Modality Average Morphine Requirements After Total Hip Arthroplasty (THA) Depodur 7.5 Depodur 10 IT Morphine PF - Fentanyl IV-PCA Fentanyl IV-PCA

7. Figure 2: Post-operative opioid requirements in patients after Total Knee Arthroplasty Average Morphine Requirements After Total Knee Arthroplasty (THA) Average Morphine Requirements (mg) Depodur 10 Depodur 10.0 Single Femoral Nerve Block + Fentanyl IV-PCA Indwelling Epidural Cathet with 0.2% Ropivicaine + Fentanyl IV-PCA Post-operative Pain Control Modality

8. Results: Table 1: Post-operative analgesic requirements of patients after Total Hip Arthroplasty

9. Results: Table 2: Post-operative analgesic requirements of patients after Total Knee Arthroplasty

10. Discussion:  Bonferoni adjustments in ANOVA showed the difference in average patient morphine requirements to be significantly less in the EREM groups (p<0.001) [Figure 1 & Table 1]  Average pain intensity after total hip arthroplasty was greater with traditional modes of post-operative pain control with intravenous PCA when compared to EREM 7.5mg and EREM 10mg (Table 1)  EREM 7.5 mg and EREM 10 mg were comparable for post-operative pain control after THA  Percentage of patients who required no opioid rescue after THA was high in EREM groups with minimal usage of pump technology  Patients after total knee arthroplasty had improved pain control and decreased supplemental opioid usage in EREM 10.0 mg and EREM 12.5 mg groups when compared to post-operative regimen with epidural and femoral nerve block  Bonferoni adjustments in ANOVA showed a significance difference in morphine requirements in EREM groups (p<0.01) on day 0 and day 1 when compared to the control groups (Figure 2 & Table 2)  The majority of patients receiving EREM after TKA required little supplemental opioids, usually managed with oral agents alone

11. Conclusion:  The majority of patients who received EREM for TJA had adequate pain control with minimal analgesic supplement Few patients required the addition of IV PCA  This study demonstrates potential ease-of-care benefits by eliminating analgesic therapies that rely on indwelling catheter and pump delivery  EREM 7.5 mg and EREM 10 mg was superior in total hip arthroplasty, while EREM 12.5 mg had higher efficacy in total knee arthroplasty

12. Limitations:  Limitations of this study include a small sample size  This was a retrospective analysis with can cause bias in:  Selection  Recording