1. A Retrospective Study Comparing Liposomal Bupivacaine versus Traditional Modalities on Post-operative Length of Stay LT Kyleigh Hupfl, PharmD 1 1 Naval Medical Center San Diego, San Diego, CA BACKGROUND Cardiothoracic surgical incisions are commonly recognized as some of the most painful surgical procedures with post-procedural pain aggravated by continuous motion of the chest wall during breathing. Effective management of acute post-cardiothoracic surgical pain is imperative to reduce pulmonary complications. Due to their proven efficacy, opioids are frequently utilized as the main component of postsurgical analgesic regimens. However, they are also associated with a variety of potentially severe opioid related adverse events including respiratory depression, nausea and vomiting, and reduced gastrointestinal motility which may negatively impact recovery time and increase length of stay. Liposomal bupivacaine is a long-acting formulation of bupivacaine that utilizes liposomal drug delivery technology. After a single injection into the surgical site the active ingredient is released via diffusion over an extended period of time. Clinical studies involving a variety of surgical settings have shown a single dose of liposomal bupivacaine administered intraoperatively can provide effective analgesia for up to 72 hours. Currently, there is no clinical evidence regarding the use of liposomal bupivacaine in invasive, painful procedures, such as cardiothoracic incisions, with respect to its effect on length of stay. The Naval Medical Center San Diego (NMCSD) approved the utilization of liposomal bupivacaine in cardiothoracic surgery in 2012. This study was designed to assess effect of liposomal bupivacaine on post-operative length of stay and opioid consumption when used as part of a comprehensive pain management strategy in cardiothoracic surgery. Evaluate the effect of liposomal bupivacaine on length of stay in post-cardiothoracic surgery patients receiving liposomal bupivacaine versus traditional pain management regimens Primary Endpoint: Post-operative length of stay (LOS) in days Secondary Endpoints: Opioid consumption 72 hours post-operative in mg of oral morphine equivalents (ME mg) OBJECTIVES METHODS This retrospective cohort study was conducted as a chart review of patients 18 years and older who underwent invasive cardiothoracic surgery between January 2012 and January 2015. Those who received liposomal bupivacaine perioperatively were compared to a control group for the primary outcome of postoperative length of stay in days measured from surgery end time to discharge. Statistical Analysis: A minimum of 96 patients per group were required to detect a 1 day difference in post-operative length of stay between the experimental and control groups with an α = 0.05 and power of 80%. The primary and secondary endpoints were evaluated using Wilcoxan Rank-Sum test. RESULTS Table 1. Baseline Characteristics DISCLOSURE LT Kyleigh B. Hupfl declares no conflicts of interest, real or apparent, and no financial interests in any company, product, or service mentioned in this poster, including grants, employment,gifts, stock holdings, and honoraria. DISCUSSION CONCLUSION Post-operative pain management requires a multimodal approach LipoB does not appear to have LOS or opioid consumption benefit over traditional approaches in invasive cardiothoracic surgeries Cost benefit analysis should be completed to determine if continued use is warranted Future Plans Potential to expand groups in effort to better match for incision type A prospective study on the use of LipoB in minimally invasive General Surgery is being planned at NMCSD Cost comparison of LipoB vs. patient controlled delivery via specialized pump REFERENCES 1.Apfelbaum JL. Practice guidelines for acute pain management in the perioperative setting: an updated report by the American Society of Anesthesiologists Task Force on Acute Pain Management. Anesthesiology. 2012; 116:248–273. 2.McGuire L, Heffner K, Glaser R, et al. Pain and wound healing in surgical patients. Ann Behav Med. 2006; 31:165–172. 3.Hughes R, Gao F. Pain control for thoracotomy. Contin Educ Anaesth Crit Care Pain. 2005; 5(2):56-60. 4.Oderda GM, Evans RS, Lloyd J, et al. Cost of opioid-related adverse drug events in surgical patients. J Pain Symptom Manage. 2003;25(3): 276–283. 5.Oderda GM, Said Q, Evans RS, et al. Opioid-related adverse drug events in surgical hospitalizations: impact on costs and length of stay. Ann Pharmacother. 2007;41(3):400–406. 6.Exparel® (bupivacaine liposome injectable suspension) [package insert]. Parsippany, NJ: Pacira Pharmaceuticals, Inc; 2011.Gorfine SR, Onel E, Patou G, et al. Bupivacaine extended release liposome injection for prolonged postsurgical analgesia in patients undergoing hemorrhoidectomy: a multicenter, randomized, double-blind, placebo-controlled trial. Dis Colon Rectum. 2011;54:1552–1559. NMCSD IRB Approval was obtained. Strengths of this study include the control group, the large sample size with a total of 200 patients, assessment of objective measures. Otherwise, limitations include its retrospective nature, groups not being matched for incision type, and significant difference in surgeon utilizing LipoB vs. control which may have led to other confounding variables such as more aggressive pain management. Table 2. Surgical Characteristics Fig. 1. Primary endpoint: Post-operative length of stay in days Fig. 2. Secondary endpoint: Post-operative opioid consumption (ME mg) * * p-value < 0.05