Pregnancy
Conditions
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.
Interventions
OTHERObstetrical patients
Epidural waveform analysis as a confirmation of loss of Resistance
Sponsors
McGill University Health Centre/Research Institute of the McGill University Health Centre
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Success rate | 15 minutes | Success rate evaluated with sensory block to ice |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Epidural waveform analysis | Immediately after epidural catheter insertion | presence or absence of an epidural waveform measured through the epidural catheter right after insertion |
Countries
Canada
Outcome results
None listed