Optimizing Local Anesthetic Concentration for Continuous Femoral Nerve Blocks

University of California San Diego

Status and phase: Completed; Phase 4

Conditions: Total Knee Arthroplasty; Knee Pain

Treatments: Drug: 0.1% and 0.4% perineural ropivicaine

Study type: Interventional

Funder types: Other

Identifiers

NCT00923598

Cleveland TKA Study

Details and patient eligibility

About

This is a randomized, observer-masked, controlled study. Subjects will be patients undergoing bilateral total knee arthroplasty (TKA). One side (left or right) will be randomized to one of two treatment groups: a postoperative ropivacaine concentration of 0.1% or 0.4%. The contralateral side will receive the other possible ropivacaine concentration of 0.1% or 0.4%. The basal rate and patient-controlled bolus volume will depend upon the treatment group, but the total dose of local anesthetic is the same for each. For the duration of the study, all patients will receive the current usual and customary analgesics for bilateral TKA patients. All patients will receive a ropivacaine perineural infusions initiated in the operating room and continued until at least the afternoon of postoperative day (POD) 2, as well as oral acetaminophen, a sustained-release oral opioid; and celecoxib. Rescue opioid and route of administration will be determined by pain severity using a Numeric Rating Scale of 0-10, with 0 equal to no pain and 10 being the worst imaginable pain.

Full description

The investigators propose to test the null hypothesis that differing concentrations of ropivacaine (0.1% vs. 0.4%) at an equal total dose has no impact on quadriceps muscle strength during a continuous femoral nerve block following total knee arthroplasty (TKA). These results will help define the optimal concentration of local anesthetic used for continuous peripheral nerve blocks.

Enrollment: 48 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Primary, bilateral TKA
• Age 18 years or older
• Postoperative analgesic pain includes bilateral continuous femoral nerve blocks

Exclusion criteria

• Chronic, high-dose opioid use
• History of opioid abuse
• Any neuro-muscular deficit of either femoral nerves and/or quadriceps muscles
• Pregnancy
• Incarceration

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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48 participants in 2 patient groups

1) 0.1% Ropivicaine on Right Leg

Active Comparator group

Description:

Patients will be randomized ot 0.1% Ropivicaine infusion on the right leg and therefore 0.4% Ropivicain in fusion for the left leg for pain due to bilateral TKA. The outcome measures will be measured on both legs, starting with the right leg each time. The infusion will last for the two days following surgery, that the patient is staying in the hospital.

Treatment:

Drug: 0.1% and 0.4% perineural ropivicaine

2) 0.4% Ropivicaine on Right Leg

Active Comparator group

Description:

Patients will be randomized ot 0.4% Ropivicaine infusion on the right leg and therefore 0.1% Ropivicain in fusion for the left leg for pain due to bilateral TKA. The outcome measures will be measured on both legs, starting with the right leg each time. The infusion will last for the two days following surgery, that the patient is staying in the hospital.

Treatment:

Drug: 0.1% and 0.4% perineural ropivicaine