Duration of Sciatic Nerve Block After Injection of Local Anesthetic In or Around the Nerve

University of Parma

Status and phase: Completed; Phase 4

Conditions: Postoperative Pain; Orthopedic Surgical Procedures

Treatments: Procedure: Patient-controlled postoperative analgesia; Drug: Mepivacaine; Procedure: Intraneural Injection for Subgluteal Sciatic Nerve Block; Procedure: Femoral Nerve Block; Procedure: Perineural Injection for Subgluteal Sciatic Nerve Block

Study type: Interventional

Funder types: Other

Identifiers

NCT01981291

ANEST-ORT-03

Details and patient eligibility

About

This study was designed to assess whether the injection of local anesthetic into the nerve (intraneural), as opposed to around it (perineural), leads to longer anesthesia and analgesia of the leg.

Some reports of accidental intraneural injection mention an extremely long duration. When different drugs and doses were evaluated in a clinical trial of intraneural injection, a longer-than-expected duration was reported.

The investigators will compare the two types of injection using the same drug, so as to determine if there is an actual difference in duration.

Full description

This randomized, controlled trial will investigate prospectively for differences in sensory and motor block duration after intra- or perineural injection of 1.5% (wt/vol) mepivacaine, a short-acting local anesthetic.

Enrollment: 120 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Undergoing non-emergent orthopedic procedure of knee, leg, foot with thigh tourniquet
• ASA Physical Status Class I-III
• Consenting to surgery under peripheral nerve block anesthesia (sciatic + femoral/saphenous block)

Exclusion criteria

• Unable to understand or communicate for the purpose of the study
• Exhibiting signs of neuropathy in the ipsilateral extremity
• Inability to satisfactorily image the sciatic nerve in the opinion of the attending anesthesiologist

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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120 participants in 2 patient groups

Perineural

Active Comparator group

Description:

Patients in this group will receive a perineural injection of mepivacaine for subgluteal sciatic nerve block, in addition to a femoral nerve block and patient-controlled postoperative analgesia.

Treatment:

Procedure: Perineural Injection for Subgluteal Sciatic Nerve Block

Procedure: Femoral Nerve Block

Drug: Mepivacaine

Procedure: Patient-controlled postoperative analgesia

Intraneural

Experimental group

Description:

Patients in this group will receive an intraneural injection of mepivacaine for subgluteal sciatic nerve block, in addition to a femoral nerve block and patient-controlled postoperative analgesia.

Treatment:

Procedure: Femoral Nerve Block

Drug: Mepivacaine

Procedure: Intraneural Injection for Subgluteal Sciatic Nerve Block

Procedure: Patient-controlled postoperative analgesia