Epidural Waveform Analysis for Thoracic Epidural Blocks

Summary

Epidural waveform analysis (EWA) provides a simple confirmatory adjunct for loss-of-resistance (LOR): when the needle/catheter tip is correctly positioned inside the epidural space, pressure measurement results in a pulsatile waveform. Epidural waveform analysis can be carried out through the tip of the needle or the catheter. In this randomized trial, the objective is to compare epidural waveform analysis through the needle (EWA-N) and through the catheter (EWA-C) for thoracic epidural blocks.

Conditions

• Surgical Procedure, Unspecified

Interventions

DEVICE

EWA through the needle

In the EWA-N group, 5 mL of normal saline are injected through the epidural needle after the occurrence of loss-of-resistance (LOR). The needle is connected to the pressure transducer. A satisfactory endpoint is defined as the presence of waveforms synchronized with arterial pulsations. In the absence of pulsatile waveforms, the operator injects an additional 2.5 mL-bolus of normal saline through the epidural needle and reconnects the latter to the pressure transducer. If no waveforms are detected after the second injection, the operator removes the needle and reattempts the epidural block at a different intervertebral level. A maximum of 3 levels is permitted: if waveforms are still absent at the third level, the operator simply accepts LOR as the technical endpoint.

DEVICE

EWA through the catheter

In the EWA-C group, the epidural catheter is advanced 5 cm beyond the needle tip after the occurrence of LOR. Subsequently, the operator injects 5 mL of normal saline through the catheter and the latter is connected to the pressure transducer via the sterile, rigid extension tubing. A satisfactory endpoint is defined as the presence of waveforms. In the absence of pulsatile waveforms, the operator injects an additional 2.5 mL-bolus of saline through the catheter and reconnects the latter to the pressure transducer. If no waveforms are detected after the second injection are still absent at the third level, the operator simply accepts this position for catheter placement (intent-to-treat analysis).

Sponsors & Collaborators

• Ramathibodi Hospital

  collaborator OTHER

• University of Chile

  collaborator OTHER

• McGill University Health Centre/Research Institute of the McGill University Health Centre

  lead OTHER

Principal Investigators

• De Q Tran, MD, FRCPC · McGill University Health Centre/Research Institute of the McGill University Health Centre

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2018-07-30

Primary Completion

2019-01-30

Completion

2019-02-02

Countries

• Chile
• Thailand

Study Locations