427 - Impact of Local Administration of Liposomal Bupivacaine for Analgesia...

#427 Impact of Local Administration of Liposomal Bupivacaine for Analgesia in Post-operative Neurosurgery Patients: A Retrospective Chart Review

Value and Outcomes in Spine Surgery

Poster Presented by: A. Cannestra

Author(s):

A. Cannestra (1,2)
B. Ryan (3)
C. Vynanek (3)
S. Gandhi (3)

(1) Lyerly Neurosurgery, Jacksonville, FL, United States
(2) University of Hawaii, John A Burns School of Medicine, Deparment of Surgery, Honolulu, HI, United States
(3) Baptist Medical Center, Pharmacy, Jacksonville, FL, United States

Abstract

Introduction: Liposomal bupivacaine (LB) is a local anesthetic FDA approved for hemorrhoidectomies/bunionectomies and has also been shown beneficial for post-operative pain control in joint replacement patients. We performed a retrospective chart review to evaluate the use of LB compared to patient controlled analgesia (PCA) in post-operative lumbar fusion patients.

Methods: All patients undergoing lumbar fusions surgeries who received LB (June 2015 to January 2016) were included as a retrospective chart review. The control group was patients undergoing lumbar fusion surgeries who were treated with Dilaudid PCA (June 2010 to May 2015). PO and PRN IV opiates remained part of the multimodal regimen in both groups. Patients were matched based on surgeon, procedure, age and opiate tolerance. Because physical therapy mobilization begins when pain scores are less than or equal to five, the primary endpoint was time to a sustained pain score of five or less. Secondary endpoints included total post-operative opiates used, length of stay (LOS) and discharge destination. A paired t-test was used to analyze the primary endpoint as well as total opiates used and LOS. McNemar's test was used to compare the proportion of patients achieving discharge to home versus rehabilitation.

Results: 41 LB patients were identified and two were excluded (due to multiple surgeries). 39 LB patients were included in the analysis and matched with thirty-nine historical controls. The mean time to a sustained pain score of 5 or less was 7.2 hours in the LB group and 9.1 hours in the PCA group (Figure 1, p = 0.26). The mean mg of morphine equivalents used was 247 in the LB group vs. 480.85 in the PCA group (Figure 2, p = 0.002). Mean LOS was 2.8 days in the LB group vs. 3.3 days in the historical control group (p = 0.1). There was no statistically significant difference in the discharge destination between the two groups using McNemar's test (p = 0.42).

Conclusions: Although not statistically significant, there may be a small difference in favor of LB in the time needed to achieve a sustained pain score of 5 or less in post-operative lumbar fusion patients. This could be due to its different mechanism of action, administration prior to the onset of pain, or duration of action as compared to PCA's. No PCA's were needed in the LB group. The LB group also required statistically-significant less post-operative opiate use compared to controls (p = 0.002). The opiate-sparing effect of this approach may result in reduced hospital costs as there is a substantial cost of PCA's implementation. LB's may also reduce sedation and improve time to mobilization while minimizing the use of anti-opiate side-effect medications such as antihistamines, antiemetics or antidiarrheals. While there was no statistically significant difference between the groups with respect to LOS or discharge destination, the LB seemed to demonstrate a shorter LOS and possibly greater proportion of patients discharged to home. The study is limited by its small sample size and the unblinded nature of the study. Additionally, LOS data may be confounded by the three-night inpatient stay requirement for Medicare patients.