Response Patterns to the Electric Stimulation of Epidural Catheters in Term Pregnant Women

Response Patterns to the Electric Stimulation of Epidural Catheters in Term Pregnant Women: A Randomized Controlled Trial of Uniport Versus Multiport Catheters.

Lumbar epidural analgesia is commonly used for labor pain relief due to its effectiveness and safety. Despite its very high success rate, the epidural technique remains a rather blind technique and failures continue to occur. The correct placement of an epidural catheter, however, remains a clinical problem, since there is no imaging technique that could be used at the bedside to determine the exact positioning of the catheter. The technique of a trans-catheter electric stimulation test (TCEST) has been successfully used to detect the proper epidural catheter location for pediatric, post-operative and laboring obstetric patients. The response to the TCEST with the uniport (single hole) epidural catheters has been well described. There is a growing body of evidence that multiport epidural catheters provide an advantage to uniport catheters, since additional ports likely allow for an enhanced distribution of the local anesthetic solution. This was shown to result in a lower incidence of inadequate analgesia, including unilateral sensory blockade and missed sensory segments. The characteristics of the TCEST response using a multiport catheter remain to be determined. The aim of this study is to compare the response patterns to the TCEST using a single port versus multiport wire reinforced epidural catheters. The hypothesis of this study is that the incidence of a bilateral response to the TCEST will be higher in the multiport catheter as compared to the uniport catheter.

Study Overview

• Status: Completed
• Conditions: Labor Pain
• Intervention / Treatment: Device: Trans-catheter electric stimulation test

Detailed Description

This will be a randomized double-blind controlled study. After recruitment of the patient, epidural anesthesia will be performed in the standard fashion employed in the investigators institution by a resident, fellow, or staff. Spinal ultrasound will be used prior to performing the epidural catheter insertion. Patients will be randomly allocated into two different groups to receive either a 19 gauge uniport catheter or a 19 gauge multiorifice catheter (Arrow Flextip plus, Arrow International Inc., Reading, PA). After securement of the catheter, the TCEST will be performed. The test will be repeated at 5 minutes, following a test dose, to determine the change in intensity of current required to elicit the motor response. Following the second testing, a loading dose of the standard anesthetic solution will be administered. The sensory level to ice will be tested at 20 minutes following injection of the loading dose of bupivacaine and fentanyl. The sensory level will be assessed from the sacral to the thoracic levels, bilaterally Failure of the epidural analgesia will be assessed, defined as no evidence of a sensory block to ice and absent pain relief. The need for catheter replacement will be determined within 2 hours of the completion of the loading dose.

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G1X5
      • Mount Sinai Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Women over 18 years of age requesting an epidural for labor and delivery
• Able to communicate in English
• Informed consent

Exclusion Criteria:

• Refusal to provide written informed consent
• Unable to communicate in English
• Allergy or hypersensitivity to lidocaine, bupivacaine or fentanyl
• Abnormal vertebral anatomy, including previous spine surgery and scoliosis
• Coexisting neurological disorders
• Implanted electronic devices

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Uniport catheter; 19 gauge uniport epidural catheter	Device: Trans-catheter electric stimulation test; Other Names: Tsui test
Active Comparator: Multiport catheter; 19 gauge multiorifice epidural catheter	Device: Trans-catheter electric stimulation test; Other Names: Tsui test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Motor response pattern	Motor response pattern to the electrical stimulation of the epidural catheter, either unilateral or bilateral	5 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Current (mA)	The current (mA) needed to elicit a motor response at control and at 5 minutes after the test dose	5 minutes
Sensory level	The sensory level to ice at 20 minutes following injection of the standard epidural loading dose. The sensory level will be assessed from the sacral to the thoracic levels, bilaterally	20 minutes
Epidural block failure	Failure of the epidural analgesia, defined as no evidence of a sensory block to ice and absent pain relief	20 minutes
Catheter replacement	Need for catheter replacement within 2 hours of the completion of the loading dose	2 hours

Collaborators and Investigators

• Sponsor: Samuel Lunenfeld Research Institute, Mount Sinai Hospital

Study record dates

Study Major Dates

• Study Start: November 1, 2014
• Primary Completion (Actual): January 1, 2015
• Study Completion (Actual): January 1, 2015

Study Registration Dates

• First Submitted: October 9, 2014
• First Submitted That Met QC Criteria: October 22, 2014
• First Posted (Estimate): October 24, 2014

Study Record Updates

• Last Update Posted (Estimate): February 19, 2015
• Last Update Submitted That Met QC Criteria: February 18, 2015
• Last Verified: February 1, 2015

More Information

Terms related to this study

• Keywords: Labour; Tsui Test; Epidural catheter
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Labor Pain
• Other Study ID Numbers: 14-05