Epidural Waveform Analysis for Thoracic Epidural Blocks

Not Applicable

Completed

• Conditions: Surgical Procedure, Unspecified
• Interventions: Device: EWA through the catheter; Device: EWA through the needle

• Registration Number: NCT03603574
• Lead Sponsor: McGill University Health Centre/Research Institute of the McGill University Health Centre

Brief 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.

Detailed Description

The epidural space is most commonly identified with loss-of-resistance (LOR). Though sensitive Epidural waveform analysis (EWA) provides a simple confirmatory adjunct for LOR. When the needle (or catheter) is correctly positioned inside the epidural space, pressure measurement at its tip results in a pulsatile waveform synchronized with arterial pulsations Currently, there exist two different methods for EWA. Since local anesthetic (LA) is administered through the catheter, pressure transduction through its tip ensures that it is properly positioned inside the epidural space prior to LA injection. Alternately, EWA can be performed through the needle prior to blind advancement of the epidural catheter.

Thus, in this randomized trial, the aim is to compare epidural waveform analysis through the needle (EWA-N) and through the catheter (EWA-C) for thoracic epidural blocks. The hypothesis is that, compared to EWA-C, EWA-N will result in a shorter performance time.

Study Timeline

• Study First Submitted: 2018-06-25
• Study First Submitted QC: 2018-07-19
• Study First Posted: 2018-07-27
• Study Start: 2018-07-30
• Primary Completion: 2019-01-30
• Status Verified: 2019-02
• Study Completion: 2019-02-02
• Last Update Submitted: 2019-02-04
• Last Update Posted: 2019-02-06

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 120

Inclusion Criteria

• age between 18 and 80 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
• coagulopathy
• renal failure
• hepatic failure
• allergy to local anesthetic
• pregnancy
• prior surgery in the thoracic spine

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
EWA through the catheter	EWA through the catheter	EWA through the catheter 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 synchronized with arterial pulsations.
EWA through the needle	EWA through the needle	EWA through the needle group, 5 mL of normal saline are injected through the epidural needle after the occurrence of LOR. The needle is subsequently connected to the pressure transducer (leveled with the heart) via the sterile, rigid extension tubing. A satisfactory endpoint is defined as the presence of waveforms synchronized with arterial pulsations.

Primary Outcome Measures

Name	Time	Method
Performance time of block	From skin infiltration until local anesthetic administration through the needle or catheter, up to 60 minutes	temporal interval in minutes between skin infiltration and local anesthetic administration through the epidural catheter (after obtaining a satisfactory waveform either through the needle or through the catheter depending on randomized group assignment).

Secondary Outcome Measures

Name	Time	Method
Procedural pain during epidural block assessed by the numeric rating scale	From the performance of the epidural block until induction of general anesthesia, up to 2 hours	pain in the back of the patient, related to the performance of the epidural block, using a numeric rating scale from 0 to 10 points (0=no pain and 10= worst imaginable pain)
Incidence of successful epidural block	15 minutes after the administration of local anesthetic through the epidural catheter	bilateral block to ice in at least 2 dermatomes
Local anesthetic consumption	once a day from the arrival at PACU or until catheter removal, up to 5 days	amount of local anesthetic consumed
Postoperative pain related to surgical incision assessed by the numeric rating scale	twice a day from the arrival at PACU or until catheter removal, up to 5 days	pain at rest and upon deep breathing/coughing, measured using a numeric rating scale from 0 to 10 points ((0=no pain and 10= worst imaginable pain)
Breakthrough opioid consumption (if required)	once a day from the arrival at PACU or until catheter removal, up to 5 days	amount of opioids consumed
Incidence of adverse events	Once a day from catheter insertion until removal, up to 5 days	side effects related to the performance of the epidural block (eg, dural/vascular puncture, paresthesia) or breakthrough opioids (nausea, vomiting, pruritus, somnolence, respiratory depression)

Trial Locations

Locations (2)

Ramathibodi Hospital; 🇹🇭 Bangkok, Thailand

Hospital Clínico Universidad de Chile; 🇨🇱 Santiago, RM, Chile