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Reliability of Waveform Analysis as an Adjunct to Loss of Resistance for Obstetrical Epidural Blocks

Not Applicable
Completed
Conditions
Pregnancy
Interventions
Other: Obstetrical patients
Registration Number
NCT02793596
Lead Sponsor
McGill University Health Centre/Research Institute of the McGill University Health Centre
Brief Summary

In this study, we will set out to confirm the reliability of epidural waveform analysis (EWA) as an adjunct to loss of resistance for obstetrical epidural blocks.

Detailed Description

After loss of resistance, 5 mL of normal saline will be injected through the epidural needle; the latter will then be connected to a pressure transducer (leveled with the heart) using a rigid tubing. A pressure recording of the epidural waveform will be saved for future assessment by a blinded observer.

After the recording of the waveform, the rigid tubing will be disconnected from the epidural needle. A 4 mL bolus of lidocaine 2% with epinephrine 5 µg/mL will be injected through the latter. An epidural catheter will be advanced 3-4 cm past the tip of the needle inside the epidural space. The needle will then be removed and the catheter secured to the skin in the usual fashion.

Fifteen minutes after the injection of the local anesthetic bolus, a blinded observer will apply ice to the T1-L5 dermatomes and assess the epidural block.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
100
Inclusion Criteria

-American Society of Anesthesiologists classification 1-3

Exclusion Criteria
  • adults who are unable to give their own consent
  • coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie platelets ≤ 100, International Normalized Ratio ≥ 1.4 or prothrombin time ≥ 50)
  • renal failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie creatinine ≥ 100)
  • hepatic failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie transaminases ≥ 100)
  • allergy to local anesthetic
  • prior surgery in the lumbar spine

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Obstetrical patientsObstetrical patientsObstetrical patients requiring epidural analgesia for delivery
Primary Outcome Measures
NameTimeMethod
Success rate15 minutes

Success rate evaluated with sensory block to ice

Secondary Outcome Measures
NameTimeMethod
Epidural waveform analysisImmediately after epidural catheter insertion

presence or absence of an epidural waveform measured through the epidural catheter right after insertion

Trial Locations

Locations (1)

Royal Victoria Hospital

🇨🇦

Montreal, Quebec, Canada

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