4-drug nerve block versus plain local anesthetic for knee and hip arthroplasty analgesia in veterans

Conditions: Pain

Summary: after total joint replacement, early hospital discharge to home (with patients capable of continuing a home-based rehabilitation program) is a cost- effective management strategy. this project will use improved local anesthetic nerve block techniques to enhance technical capability and clinical practice by (i) reducing pain and other morbidities during recovery, (ii) improving weight-bearing achievement during in-hospital physical therapy to allow for earlier return home, and (iii) continued rehabilitation as an outpatient at home when feasible (versus in an extended care facility).

patients will have spinal anesthesia for their hip or knee replacement surgery. they will also receive the nerve blocks described above

Eligibility criteria:
inclusion criteria: 1. age between 18 and 85, and undergoing a total knee or hip replacement. 2. fluent in english, decision competent, willing and able to provide written informed consent, and able to complete the study's schedule of assessments. 3. able to walk \>3m without an assisting device. 4. have a bmi ≤ 40 kg/m2. exclusion criteria: 1. current participation in another orthopedic/physical therapy/rehab/anesthesiology interventional clinical trial. 2. are at significant behavioral risks or have refractory major psychiatric disorders. 3. revision surgery on the same extremity. 4. have an american surgical association (asa) physical status classification of 4 or higher. 5. have been diagnosed with clinically significant neuropathy with its origins in either diabetes or other causes; have neuromuscular disease that would influence data collection. 6. have a surgically-fused lumbar spine, or a spinal cord simulator, or other condition that would contraindicate or prohibit the conduct of spinal anesthesia. 7. at significant risk for postoperative substance abuse, or immediate-postoperative substance abuse withdrawal symptoms (alcohol, cocaine, enrolled in methadone or buprenorphine opioid withdrawal programs, etc.) previous or current use of marijuana will not be an exclusion for study enrollment. 8. are undergoing total knee arthroplasty (tka)/total hip arthroplasty (tha) for a tumor. 9. have contraindications (e.g., anaphylaxis) to any of the study drugs. 10. have a systemic fungal infection. 11. have a known hypersensitivity to bupivacaine hydrochloride or to any local anesthetic of the amide-type or to other components of bupivacaine hydrochloride solutions. 12. have a known or suspected buprenorphine hypersensitivity (not including nausea and/or vomiting). 13. have a gastro-intestinal (gi) obstruction. 14. have paralytic ileus. 15. pregnant women 16. have had a kidney or liver transplant. veterans will not be excluded from participation based on smoking status, diagnosis of obstructive sleep apnea, or baseline monitored consumption of therapeutic opioids for documented medical indications; instead, these variables will be codified and quantified for subsequent covariate statistical analysis.

Keywords: analgesia, buprenorphine clonidine dexamethasone bupivacaine nerve block