Comparing Post-Op Narcotic Usage in Patients Receiving Periarticular Exparel vs. Standard Periarticular Joint Inj

Phase 4

Completed

Interventions: Drug: (Bupivacaine Liposome Injectable Suspension)
Drug: Standard Preparation

Brief Summary: This study seeks to determine whether a new sustained-release local anesthetic solution (Exparel - Liposomal Bupivacaine) injected into the soft tissues around the joint after surgery will decrease opioid consumption and adverse events in opioid-tolerant patients presenting for total knee arthroplasty. The research hypothesis is that the Exparel (study) group will use less opioid in the first 48 hours post-operatively than the control group.

Detailed Description: Opioids have been prescribed with increasing frequency for non-acute, non-cancer pain in the last 15 years. Because of this, opioid tolerance in the general population has grown markedly, and opioid tolerant patients can be especially difficult to manage in the perioperative period. In general, they require much higher doses of opioids to obtain similar levels of pain-control compared to opioid-naïve patients and are susceptible to respiratory depression and other adverse events. This study seeks to determine whether a new sustained-release local anesthetic solution (Exparel - Liposomal Bupivacaine) injected into the soft tissues around the joint after surgery will decrease opioid consumption and adverse events in opioid-tolerant patients presenting for total knee arthroplasty.

Recruitment & Eligibility

Inclusion Criteria

Control group- received standard periarticular injection Research group- receives Exparel injection

Exclusion Criteria

Allergy to local Anesthetic
Pregnancy
Nursing mothers
Children<18 years of age
Renal impairment (GFR<60 mL/min/1.73 m^2
Hepatic impairment (active hepatitis, elevated AST or ALT, jaundice)
Any history of ventricular arrhythmia or supraventricular tachycardia, or myocardial infarction within the last six months.

Arm && Interventions

Group	Intervention	Description
EXPAREL® Bupivacaine Liposome Suspension	(Bupivacaine Liposome Injectable Suspension)	Instead of injecting the standard joint injection for a case of total knee arthroplasty, Exparel-Liposomal Bupivicaine will be administered at the end of the surgery. A new sustained-release local anesthetic solution (Bupivacaine Liposome Injectable Suspension) will be injected into the soft tissues around the join after surgery. Exparel is a novel-composition of bupivacine in which the drug is dissolved into liposomes which release it slowly over a period of 72 hours.
Standard periarticular joint injection	Standard Preparation	A standard joint injection of 100ml (Clonidine 80 mcg, Epinephrine 0.5mg, Ketorolac 30mg, Ropivacaine 246.25mg, and Sodium Chloride 0.9% 48.45 ml) will be injected into the soft tissues around the joint after surgery.

Primary Outcome Measures

Name	Time	Method
48 Hour Post-surgical Opioid Use	48 hours	A comparison of group means between the control group and study group with regards to 48 hour opioid use.

Secondary Outcome Measures

Name	Time	Method
Average Daily Patient Pain Score	Up to 48 hours	Examining the average daily patient pain score in comparison of standard knee injection post-operatively. The measure is the Visual-Analog-Scale (VAS) for subjective pain reporting. The minimum 0 (no pain) and the maximum is 10 (worst pain imagineable). There is only one measure in the scale (i.e. there are no subscales). Lower scores on the VAS scale equate to less pain and are therefore desirable.
Average Daily Opioid Use During Admission	Up to 48 hours	Opioid use will be monitored daily from the time of admission in comparison of standard knee injection post-operatively.
Recovery Room Opioid Use	Up to 48 hours	Post anesthesia care unit (recovery room) opioid use in total mg morphine IV equivalent in comparison of standard knee injection post-operatively.
Post-operative Complications	Up to 1 month	Examining the post-operative complication in comparison of standard knee injection post-operatively.