Abstract ID: A45

Abstract Title: Analgesic Benefit of Femoral Nerve Block When Added Postoperatively to Morphine IVPCA in Patients Undergoing Total Knee Arthroplasty

Authors: Lasner H1, Claudio R2, Lakshman S3, Iwata T4
         St Luke's-Roosevelt Hospital Center New York NY US1, St Luke's-Roosevelt Hospital Center New York NY US2, St Luke's-Roosevelt Hospital Center New York NY US3, St Luke's-Roosevelt Hospital Center New York NY US4
Poster Type: Poster


ABSTRACT BODY

Introduction:
Femoral nerve blocks (FNB) have been increasingly used as an adjunct to intravenous opioids for pain management in patients undergoing total knee arthroplasty (TKA)1,2. Intravenous opioid use alone is commonly associated with incomplete pain relief and opiod-related side effects, which interfere with early rehabilitation and may lead to delayed recovery, prolonged hospitalization, and greater use of health-care resources.3,4,5 In this study, we specifically looked into the analgesic benefit of FNB when added postoperatively to intravenous patient controlled analgesia (IVPCA).

Materials and Methods:
All patients received neuraxial anesthesia for the surgery and IVPCA for postoperative pain management, Figure 1. Patients with pain ©ø 6 on a visual analog scale of 1-10 received a FNB (0.5% ropivacaine). PACU records of 35 patients having TKA were randomly selected for this analysis. The following main data was extracted: patient demographics, VAS scores and morphine consumption. The data was analyzed using descriptive statistics, Student t-test and t-tests for paired comparisons, where applicable.

Results:
Demographics of the patients are presented in Table 1. Five patients (14%) did not require adjunct intervention to the morphine IVPCA. Of note, these five patients tended to be older than those who required FNB (75 yrs ¡¾ 6.0 vs 66 yrs ¡¾ 9.5, p=0.06). The remaining 30 patients (86%) required FNB for adequate pain control. In the immediate postoperative period, morphine consumption prior to the FNB was noted to be 21.6 mg ¡¾ 11.0. The maximum VAS scores before and after the FNB in these patients were 8.2 ¡¾ 1.7 and 3.6 ¡¾ 2.6, respectively (p< 0.01).

Discussion:
The addition of FNB to IVPCA significantly improved analgesia in patients after TKA. Upon performance of FNB in the immediate postoperative period, the VAS scores substantially decreased in all patients; 60% of patients were left with only minor discomfort (VAS ¡Â 3). The analgesic benefit of FNB tended to be of greater value in younger patients. In conclusion, in patients undergoing TKA, the addition of FNB in the immediate postoperative period conferred a significant analgesic benefit to the IVPCA.

References:
1. Anesth Analg 2006 Jan;102(1):87-90.
2. Anesth Analg 2005 Dec;101(6):1824-9.
3. J of Bone and Joint Surgery 2005 Nov; 87A:63-70.
4. Anesthesiology 2005 Nov; 103(5): 1079-1088.
5. Reg Anesth Pain Med 2002 Nov-Dec;27(6):604-11.


ATTACHED FILES

A45_Figure 1 - Lasner.ppt

A45_Table 1 - Lasner.doc



Reg Anesth Pain Med 2005; 30(3):A45