Tsui Test as a Predictor of Bupivacaine Consumption in Labour Epidurals

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00792311
Recruitment Status : Completed
First Posted : November 17, 2008
Last Update Posted : March 26, 2010
Information provided by:
Samuel Lunenfeld Research Institute, Mount Sinai Hospital

November 13, 2008
November 17, 2008
March 26, 2010
November 2008
August 2009   (Final data collection date for primary outcome measure)
Consumption of bupivacaine in mg/hour in the first 2 hours of epidural anesthesia [ Time Frame: 2 hours ]
Same as current
Complete list of historical versions of study NCT00792311 on Archive Site
  • Incidence of inadequate epidural block. [ Time Frame: 2 hours ]
  • Current (mA) needed to elicit motor response; 1. before test dose and 2. 5 minutes after test dose. [ Time Frame: 5 minutes ]
  • Contraction pattern elicited by the Tsui test at baseline and after test dose. [ Time Frame: 5 minutes ]
Same as current
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Tsui Test as a Predictor of Bupivacaine Consumption in Labour Epidurals
Tsui Test as a Predictor of Bupivacaine Consumption in Labour Epidurals
Low current electrical stimulation test, also called the Tsui test, has been used successfully to confirm the catheter location in the epidural space in various patient populations. The results of this study will show whether or not doing a Tsui test can predict inadequate epidural analgesia early in the course of placing the epidural, so that the appropriate measures could be applied immediately upon gathering unfavorable results.

Despite its very high success rate, the epidural technique remains a rather blind technique, and failures continue to occur. The incidence and reasons for failure are not well understood. The Tsui test is not routinely performed with each epidural catheter insertion, but rather it is used when there is suspicion about the catheter location.

In this study, the Tsui test will be performed twice during the epidural procedure, and bupivacaine consumption will be recorded for the first 2 hours.

Information gained from this study could have great impact in clinical practice, since the incidence of inadequate labor analgesia is still relatively high (10-20%), leading to maternal distress and disappointing labor experience.

Not Applicable
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Procedure: Tsui test
The stimulator is set at frequency of 1Hz with 200ms pulse width and the current output ranging from 0 to 20 mA. The current output will be carefully increased from zero until motor activity is detected up to a maximum of 20 mA.
Experimental: Tsui test
Tsui test administration.
Intervention: Procedure: Tsui test
Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
August 2009
August 2009   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Women over 18 years of age requesting an epidural for labor and delivery
  • Cervix dilated 0-5 cm and pain VAS>6
  • Able to communicate in English
  • Informed consent

Exclusion Criteria:

  • Refusal to provide written informed consent
  • Patients unable to communicate in English
  • Contraindication to regional anesthesia
  • Allergy or hypersensitivity to lidocaine, bupivacaine or fentanyl
  • Sedatives or opioids received prior to insertion of epidural catheter
  • Abnormal vertebral anatomy, such as previous spine surgery and scoliosis
  • Coexisting neurological disorders
  • Patients with implanted electronic devices
Sexes Eligible for Study: Female
18 Years to 50 Years   (Adult)
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Dr. Jose C.A. Carvalho, Mount Sinai Hospital
Samuel Lunenfeld Research Institute, Mount Sinai Hospital
Not Provided
Principal Investigator: Jose CA Carvalho, MD MOUNT SINAI HOSPITAL
Samuel Lunenfeld Research Institute, Mount Sinai Hospital
March 2010

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP