Motor-Sparing Femoral Nerve Block Dose

Minimum Effective Concentration of Bupivacaine for Motor-Sparing Femoral Nerve Block

Status

Terminated

Phases

Phase 4

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02909257

Enrollment

Registered

2016-09-21

Start date

2016-09-30

Completion date

2017-12-31

Last updated

2020-05-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Knee Injuries, Osteoarthritis, Knee

Brief summary

Femoral nerve blocks are commonly used to provide pain control for total knee replacement, anterior cruciate ligament (ACL) reconstruction. Commonly employed local anesthetic concentrations result in motor block of the quadriceps and constitute an inherent risk factor for patient fall. The aim of this study is to determine the minimum effective concentration of bupivacaine in 90 % of patients (MEC90) required for a motor-sparing, successful sensory block of the femoral nerve.

Detailed description

With the approval of Ethics Committee of the University of Chile Clinical Hospital, approximately 60 patients undergoing ACL repair or TKR will be recruited. All blocks will be conducted preoperatively in an induction room.Dose assignation will be done using an up-and-down sequential method, where the dose of each subsequent patient depends on the response of the previous patient, called the Biased Coin Design. The assignment of each subsequent concentration will be based on the response of the previous patient.As soon as we recruit 45 patients with random dose assignment, we will terminate the enrollment procedure. The injectate will be prepared and administered by a research assistant using syringes connected to the block needle. The operator and the patient will be blinded to the concentration injected.

Interventions

DRUGSame Bupivacaine Concentration

patient is exposed to the same concentration than previously successful one

DRUGLower Bupivacaine Concentration

patient is exposed to a lower concentration than previously successful one

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

SUPPORTIVE_CARE

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 75 Years

Healthy volunteers

Inclusion criteria

* Age between 18 and 75 years * American Society of Anesthesiologists classification 1-3 * Body mass index between 20 and 35

Exclusion criteria

* Adults who are unable to give their own consent * Pre-existing neuropathy (assessed by history and physical examination) * Coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. platelets≤ 100, International Normalized Ratio≥ 1.4 or partial prothrombin time ≥ 50) * Renal failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. creatinine ≥ 100) * Hepatic failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. transaminases ≥ 100) * Allergy to LA * Pregnancy * Prior surgery in the inguinal region * Chronic pain syndromes requiring opioid intake at home

Design outcomes

Primary

Measure	Time frame
Minimum Bupivacaine Analgesic concentration preserving quadriceps strength analgesia	5 months

Countries

Chile

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026