Prospective RCT Lidocaine & Levobupivacaine on Block Dynamics After Subparaneural Popliteal Sciatic Nerve Block

Summary

Sciatic nerve block at the popliteal fossa is indicated for foot or ankle surgery, and the introduction of ultrasound guidance (USG) has improved the ease and accuracy of the performance of this block. Recent studies proved that subparaneural injection is associated with faster block onset, higher block success rate, and prolonged block duration suggesting subparaneural compartment of the sciatic nerve is a desirable site for local anaesthetic injection. Data from an ongoing trial in the investigator's institution comparing the block dynamics of subparaneural injection of 30ml 0.5% levobupivacaine (Chirocaine) above and below the bifurcation of the sciatic nerve at popliteal fossa has also shown that the time to 'readiness for surgery' was faster when the injection was performed below the bifurcation of the sciatic nerve. Lidocaine (Xylocaine) has a better pharmacokinetic and pharmacodynamics profile than levobupivacaine and is also widely used as local anaesthetic agent in clinical practice. Since there is no data comparing the block dynamics of lidocaine and levobupivacaine, this study aims to study and compare the block dynamics of lidocaine and levobupivacaine when given as a subparaneural injection below the bifurcation of the sciatic nerve at the popliteal fossa. In this study, the investigator hypothesizes that the use of lidocaine as the sole agent for this block will fasten the time to 'readiness for surgery' as compared to levobupivacaine when given as a subparaneural injection below the bifurcation of the sciatic nerve at the popliteal fossa.

Conditions

• Musculoskeletal Diseases or Conditions

Interventions

DRUG

0.5% Levobupivacaine

The plane where the sciatic nerve bifurcates will at first be identified by utlrasound. 22-gauge insulated nerve block needle will be inserted in the short axis (out-of-plane) of the ultrasound transducer, and advanced toward the cleavage between the common peroneal nerve and the tibial nerve, which is the easiest location for needle access into subparaneural compartment.Once the needle tip enters the subparaneural compartment 2-3 ml of normal saline will be injected (hydro-distension) to create a halo around both the common peroneal nerve and tibial nerve distally and the sciatic nerve proximally. The needle is then redirected to place its tip into the paraneural sheath of the common peroneal and tibial nerve through the same skin puncture and 15ml of study drug will be injected at each site (total 30ml).

DRUG

2% Xylocaine with adrenaline 1:200,000

The plane where the sciatic nerve bifurcates will at first be identified by utlrasound. 22-gauge insulated nerve block needle will be inserted in the short axis (out-of-plane) of the ultrasound transducer, and advanced toward the cleavage between the common peroneal nerve and the tibial nerve, which is the easiest location for needle access into subparaneural compartment.Once the needle tip enters the subparaneural compartment 2-3 ml of normal saline will be injected (hydro-distension) to create a halo around both the common peroneal nerve and tibial nerve distally and the sciatic nerve proximally. The needle is then redirected to place its tip into the paraneural sheath of the common peroneal and tibial nerve through the same skin puncture and 15ml of study drug will be injected at each site (total 30ml).

Sponsors & Collaborators

• Chinese University of Hong Kong

  lead OTHER

Principal Investigators

• Manoj K Karmakar, MD · Chinese University of Hong Kong

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-09-20

Primary Completion

2026-09-30

Completion

2026-09-30

Countries

• Hong Kong

Study Locations