Does Ultrasound Increase the First-pass Success of Epidural Space Identification in Obese Parturients

Does Preprocedural Ultrasound Exam of Lumbar Spine Increase the First-pass Success Rate of Epidural Space Identification Among Obese Parturients: A Randomized Controlled Open Trial

Obesity is associated with difficulties in epidural space catheterization. The investigators want to prove that a pre-procedural ultrasound exam of lumbar spine increase the first-pass success rate of the epidural space identification among obese parturients.

Study Overview

• Status: Completed
• Conditions: Epidural; Anesthesia
• Intervention / Treatment: Device: Preprocedural ultrasound exam of lumbar spine

Detailed Description

This study was a randomized controlled open trial with two parallel groups.

Study was conducted in only one center : the maternity of University Hospital of Caen (Normandy, France)

Written informed consent was obtained from eligible subjects after the pre-anesthetic interview in the 8th month of pregnancy.

Operators were medical interns or residents in anesthesiology. Before inclusion, they all spent an individual interview in the aim to practice ultrasound exam of lumbar spine.

Eligible subjects were full-term parturients with pre-pregnancy BMI ≥ 30 kg/m2 undergoing vaginal delivery and receiving epidural labor analgesia. Exclusion criteria were usual contraindications for neuraxial anesthesia, marked spinal deformity, previous spinal surgery and emergency context.

The study subjects were randomly assigned to palpation or ultrasound using sealed opaque envelopes containing group allocation.

Standard monitors were applied and patients were positioned sitting during landmark identification and throughout the anesthetic procedure.

In control group, needle-puncture site was determinate by the conventional technique of cutaneous palpation. Conventional palpation of the anatomical landmarks was performed and the intercristal line (Tuffier) was assumed to cross the spine at L4 spinous process or L3-L4 interspace. The skin was marked with horizontal and vertical lines at the L3-L4 and L2-L3 interspaces.

In experimental group, ultrasound exam of lumbar spine allowed to determinate the puncture site. A systematic approach described by Balki [1] was performed, using a portative ultrasound device with a 5-2 MHz curved array probe (Samsung HM70A, Samsung medical France, St-Ouen, France).

The epidural space was located using a midline approach with loss of resistance (saline solution) using and 18-gauge Tuohy needle. After successful identification of the epidural space, a 20-gauge multiorifice epidural catheter was inserted through the Tuohy needle up to 5 cm into the epidural space.The epidural analgesia protocol was PCEA (Patient Controled Epidural Analgesia) using subsequent admixture : lévo-bupivacaïne (0,625 mg/ml), sufentanil (0,02 µ/ml), clonidine (37 µg/ml).

The primary outcome was the rate of successful epidural space identification at the first needle pass (one skin puncture without redirection).

Secondary outcomes are described further.

Early procedural complications and delivery modalities (C-section, forceps) were notified.

An interview was planned 48 hours after the procedure for each parturient in the aim to assess the maternal satisfaction and detect late procedure complications.

Assuming α = 0.05 and β = 0.2 (80% power) risks and using the χ2 test, 28 patients were required in each group.

• Study Type: Interventional
• Enrollment (Actual): 56
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Caen, France, 14000
    • University hospital of Côte de Nacre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: ADULT; OLDER_ADULT; CHILD
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Full-term parturients (≥ 37 weeks of amenorrhea)
• With pre-pregnancy BMI ≥ 30 kg/m2
• Admit for a vaginal delivery
• Receiving labour epidural analgesia

Exclusion Criteria:

• Usual contraindications for neuraxial anesthesia (thrombocytopenia, coagulopathy, uncorrected hypovolemia, infected puncture site, intracranial hypertension)
• Emergency maternal and foetal cases
• Twin pregnancy
• Marked spinal deformity ou previous spinal surgery
• Refusal to participate

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
NO_INTERVENTION: palpation; Usual method to determinate needle puncture site
EXPERIMENTAL: Ultrasound; Ultrasound preprocedural exam used to determinate needle puncture site	Device: Preprocedural ultrasound exam of lumbar spine; Preprocedural ultrasound exam of lumbar spine used to determinate needle puncture site

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Success of the epidural space identification at the first needle pass	Succes rate of the epidural space identification at the first needle pass (first skin puncture and without needle redirection) for each group	Baseline up to 1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Success of the epidural space identification at the first skin puncture	Success rate of the epidural space identification at the first needle pass (first skin puncture with at least one redirection) for each group	Baseline up to 1 hour
Number of skin punctures	Number of skin punctures per parturient	Baseline up to 1 hour
Number of needle redirections	Number of needle redirections per parturient	Baseline up to 1 hour
Number of intervertebral space punctured	Number of intervertebral space punctured per parturient	Baseline up to 1 hour
Duration of the epidural procedure	Duration of the epidural procedure in seconds, measured from the first skin puncture to the test dose	Baseline up to 1 hour
Early Failed of the epidural analgesia	Early Failed epidural analgesia, defined by the epidural analgesia remplacement within 30 minutes	30 minutes after the end of the procedure
Verbal Rating Scale	Verbal Rating Scale (VRS) of pain measured after the epidural procedure : from 0 (no itch) to 10 (worst imaginable itch)	30 minutes and 120 minutes after the epidural procedure
Accidental Dural puncture	Occurence of accidental dural puncture during the epidural procedure	Baseline up to 1 hour
Post dural puncture headache	Occurence of Post dural puncture headache after the epidural procedure	48 hours after the epidural procedure
Quality of epidural analgesia	Maternal perception of epidural analgesia quality during the labour : from 1 (very bad) to 5 (excellent)	48 hours after the epidural procedure
Maternal perception of the duration of the epidural procedure	Maternal perception of epidural procedure duration : from 1(very short) to 5 (very long)	48 hours after the epidural procedure

Collaborators and Investigators

• Sponsor: University Hospital, Caen
• Investigators: Principal Investigator: Lise-Amelie ZERAJIC, MD, Anesthesiologist Intensivist Physician

Publications and helpful links

General Publications

• Balki M. Locating the epidural space in obstetric patients-ultrasound a useful tool: continuing professional development. Can J Anaesth. 2010 Dec;57(12):1111-26. doi: 10.1007/s12630-010-9397-y. Epub 2010 Nov 11. English, French.

Study record dates

Study Major Dates

• Study Start (ACTUAL): April 6, 2019
• Primary Completion (ACTUAL): April 8, 2019
• Study Completion (ACTUAL): February 28, 2020

Study Registration Dates

• First Submitted: March 29, 2020
• First Submitted That Met QC Criteria: April 17, 2020
• First Posted (ACTUAL): April 20, 2020

Study Record Updates

• Last Update Posted (ACTUAL): May 5, 2020
• Last Update Submitted That Met QC Criteria: May 4, 2020
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Keywords: ultrasound; obesity; epidural analgesia; vaginal delivery
• Other Study ID Numbers: 2018-A02752-53

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No