Prolonged Popliteal Fossa Nerve Blockade (Prolonged Pop)

Phase 1

Completed

Brief Summary: This study looks at addition of medications to the local anesthetic for the nerve blockade.

Detailed Description: Following major foot and ankle surgery patients complain of severe pain. Currently, Hospital for Special Surgery (HSS) usually uses nerve blocks (injections of local anesthetic near nerves supplying the lower leg) to help manage pain after this type of surgery. Patients also receive additional pain pills, including narcotics as needed. This study looks at addition of medications to the local anesthetic for the nerve blockade. The investigators hope that these medications (dexamethasone and buprenorphine) will prolong the pain relief from the nerve block. There are 3 groups in the study. One group is a control, and receives usual therapy: nerve block + pain pills. This is typically what the patient would receive as standard care if they were not in the study. One group uses a nerve block with additives (+ pain pills). One group gets a nerve block (local anesthetic only) + pain pills + intravenous buprenorphine - this is meant to see if the buprenorphine acts directly on the nerve that was blocked, or indirectly acts on the brain.

Patients will be followed while in the hospital, and contacted by telephone and/or email after discharge for 2-3 days. Patients will be asked about their pain levels and the duration of their block. The investigators will enroll 90 patients.

Recruitment & Eligibility

Inclusion Criteria

Patients of Dr. Levine or Dr. Roberts at Hospital for Special Surgery
Patients aged 18-75
Patients scheduled for discharge from HSS after foot or ankle surgery
A single-injection popliteal fossa nerve block is judged appropriate
Surgery confined to foot and ankle (no iliac crest bone graft planned - iliac aspirate is not an exclusion criterion)

Exclusion Criteria

< 18 and > 75
Surgery that will cause pain at sites outside the distal lower extremity (e.g. iliac crest bone graft)
Bilateral surgery
Chronic pain (defined as regular use of opioid analgesics for > 3 months)
Chronic use of steroids (defined as regular use of steroids for > 3 months)
Contraindication to performance of the popliteal fossa nerve block with 30 cc 0.25% bupivacaine (e.g. alleged bupivacaine sensitivity, low body weight, etc.)
Contraindications to dexamethasone or buprenorphine (e.g. allergy, insulin dependent diabetes mellitus, etc.)
Patients who have been diagnosed with altered pain perception or have lack of sensation
Inability of the patient to describe postoperative pain (e.g. psychiatric disorder, dementia)
Non-English speaking patients (the questionnaire is in English, and translations would have to be separately validated)

Arm && Interventions

Group	Intervention	Description
NB with Dex + Bup in block.	Buprenorphine	Dexamethasone (4 mg) Buprenorphine (150 mcg)
Control NB + IV Dex + IV Bup	Dexamethasone	IV Dexamethasone (4 mg) + IV Buprenorphine (150 mcg)
Control NB + IV Dex + IV Bup	Buprenorphine	IV Dexamethasone (4 mg) + IV Buprenorphine (150 mcg)
Control NB + IV Dex	Dexamethasone	IV Dexamethasone (4 mg)
NB with Dex + Bup in block.	Dexamethasone	Dexamethasone (4 mg) Buprenorphine (150 mcg)

Primary Outcome Measures

Name	Time	Method
Numeric Rating Scale (NRS) Pain Score With Movement	24 hours after the popliteal block is given	Pain with movement at 24 hours from the nerve block (0-10; 0 = no pain, 10 = worst possible pain)

Secondary Outcome Measures

Name	Time	Method
Block Duration	24 hours and 48 hours after the popliteal block is given	When did the nerve block entirely wear off?
Numeric Rating Scale (NRS) Pain Score at Rest	24 hours after the popliteal block is given	Pain at rest at 24 hours from the nerve block (0-10; 0 = no pain, 10 = worst possible pain)
Median Time to Requiring Oral Opioids	24 hours after the popliteal block is given	Did patient have pain requiring oral opioids?