The purpose of this study is to quantify the total blood serum levels of bupivacaine in OrthoPAT® collected blood 2 hours and 5 hours postoperatively.

Hypothesis: Filtered blood from the OrthoPAT® autotransfusion system contains low or undetectable levels of bupivacaine hydrochloride (HCL). Reinfusion of collected blood from the OrthoPAT® device when used in conjunction with periarticular bupivicaine injections will not pose a bupivocaine toxicity risk to patients undergoing a total joint arthroplasty.

Total joint arthroplasty (TJA) is a commonly performed surgical procedure that can result in considerable postoperative pain which can limit social and functional recovery and a return to quality of life. Traditionally, pain control following TJA has been conducted with parenteral and oral narcotics. Recently, a number of studies have demonstrated the efficacy of multimodal analgesia following a variety of surgical procedures.1-2 These multimodal regimens vary and consist of any number of medications including narcotics, non-steroidal anti-inflammatories, anti-epileptics, and peripheral nerve blocks among others. These multimodal regimens have been associated with a reduction in the use of opioid analgesics, leading to fewer opioid-associated adverse events.3-5 One of the newest modalities introduced on the market is liposomal bupivacaine, trade name Exparel. The advertised advantage of liposomal bupivacaine compared with bupivacaine HCL is a longer duration of analgesia owing to gradual release from the liposomes. Liposomal bupivacaine is employed in a periarticular injection at the conclusion of TJAs to aid in post-operative pain control.

Patients receive a periarticular injection of liposomal bupivacaine intra-operatively during TJA. At the conclusion of the procedure, a specialized intra-articular drain (OrthoPAT®) is placed. The OrthoPAT® perioperative autotransfusion system collects the patient's blood in the immediate postoperative period and then allows for it to be transfused to the patient while on the floor.

A potential risk, although low, is the concern for bupivicaine toxicity. Toxicity from bupivicaine is associated with central nervous system issues (seizures) and cardiac toxicity. Toxicity is dose dependent and recommended levels should not exceed 400mg/24 hr period. With autotransfusion, there is a theoretical concern that blood, potentially with increased levels of bupivicaine, could be reinfused into the vascular system and create toxicity.

Inclusion Criteria:

• Patients undergoing primary total joint arthroplasty with use of periarticular bupivicaine and liposomal bupivicaine and OrthoPAT® auto reinfusion system.
• At least 18 years of age.

Exclusion Criteria:

• Allergy to bupivacaine.
• Allergy to epinephrine.
• Patients that are not presenting for a primary TJA
• Patients who are having a TJA without OrthoPAT® auto reinfusion system.
• Patients under age 18.

Patients presenting for total knee replacement

Patients that completed the study.

Hospital discharge following arthroplasty.