Clinical trial NCT05361512: Characteristics of the Tsui Test and Pressure Waveform to Confirm Epidural Catheter Placement in Parturients With BMI ≥50 kg/m2
Official title: Characteristics of the Tsui Test and Pressure Waveform to Confirm Epidural Catheter Placement in Parturients With BMI ≥50 kg/m2
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Labor Pain
Keywords: epidural catheter
epidural analgesia
cesarean section
Tsui test
epidural waveform
Lead sponsor: Samuel Lunenfeld Research Institute, Mount Sinai Hospital
Sponsor class: OTHER
First posted: 2022-05-04
Enrollment: 20
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 55
Standard ages: ADULT
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Parturients with BMI≥50 kg/m2 requesting epidural labor analgesia or undergoing elective cesarean delivery.

Brief summary: The prevalence of obesity has increased worldwide, and the anesthetic care of patients with obesity remains a challenge for providers despite advances. Obesity during pregnancy is a risk factor for hypertensive disorders, gestational diabetes, emergency cesarean section and higher prevalence of difficult airway. Neuraxial techniques should always be preferred in women with obesity, particularly in those with body mass index (BMI) ≥50 kg/m2, where complications can be magnified. It is estimated an overall epidural failure rate of 4.3% in patients with obesity and an epidural failure rate of 13.7% in those with BMI ≥50 kg/m2. Hence, a confirmatory test of epidural catheter placement should prove useful in this patient population. The epidural electrical stimulation test (EEST) and the epidural waveform analysis are tests described in the literature as confirmatory methods for accuracy of placement of the epidural catheter.

The Tsui test has been well studied in obstetric patients, including required threshold electric currents and muscle contraction patterns. However, these studies have been conducted in patients receiving lumbar epidural catheters. Furthermore, they have not specifically included women with obesity class 3, particularly those with BMI≥50 kg/m2. In a recent study conducted in our department, the investigators have observed that patients with BMI≥50 kg/m2 require placement of an epidural catheter at a low-thoracic or high lumbar interspace, to allow the provision of effective surgical anesthesia for cesarean delivery, which often requires a modified incision, either transverse supra-umbilical or infra-umbilical. There are only few studies with waveform confirmation in obstetric patients showing conflicting results and certainly no studies under the circumstances described above. Finally, the Tsui test and the epidural waveform analysis have never been compared in the obstetric population.

The investigators aim to describe the characteristics of the Tsui test and of the epidural waveform analysis in parturients with BMI≥50 kg/m2 receiving epidural catheter placement at T12-L1 for both labor analgesia or anesthesia for cesarean delivery

Detailed description: The Tsui test has been well studied in obstetric patients, including required threshold electric currents and muscle contraction patterns. However, these studies have been conducted in patients receiving lumbar epidural catheters. Furthermore, they have not specifically included women with obesity class 3, particularly those with BMI≥50 kg/m2. In a recent study conducted in our department, the investigators have observed that patients with BMI≥50 kg/m2 require placement of an epidural catheter at a low-thoracic or high lumbar interspace, to allow the provision of effective surgical anesthesia for cesarean delivery, which often requires a modified incision, either transverse supra-umbilical or infra-umbilical. There are only few studies with waveform confirmation in obstetric patients showing conflicting results and certainly no studies under the circumstances described above. Finally, the Tsui test and the epidural waveform analysis have never been compared in the obstetric population.

Eligibility criteria: Inclusion Criteria:

- Parturients with BMI≥50 kg/m2 requesting epidural labor analgesia or undergoing elective cesarean delivery

Exclusion Criteria:

* contraindication to epidural anesthesia
* allergy or hypersensitivity to lidocaine, bupivacaine or fentanyl
* those with implanted electronic devices.

Primary outcomes:
measure: Tsui test motor response: questionnaire
timeFrame: 15 minutes
measure: epidural waveform test (catheter) - questionnaire
timeFrame: 15 minutes
Secondary outcomes:
measure: epidural waveform test (needle) - questionnaire
timeFrame: 15 minutes
measure: Tsui test motor response (before test dose): questionnaire
timeFrame: 15 minutes
measure: Tsui test current threshold (baseline)
timeFrame: 15 minutes
measure: Tsui test current threshold (after test dose)
timeFrame: 15 minutes
measure: Laterality of the Tsui test: questionnaire
timeFrame: 15 minutes
measure: Location of muscle group response to Tsui test: questionnaire
timeFrame: 15 minutes
measure: Need for catheter mobilization: questionnaire
timeFrame: 15 minutes
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Mount Sinai Hospital
state: Ontario
Study officials:
affiliation: MOUNT SINAI HOSPITAL
name: Jose Carvalho, MD
role: PRINCIPAL_INVESTIGATOR
References: