Characteristics of the Tsui Test and Pressure Waveform to Confirm Epidural Catheter Placement in Parturients With BMI ≥50 kg/m2
- Conditions
- Labor Pain
- Interventions
- Device: Tsui testDevice: epidural waveform analysis
- Registration Number
- NCT05361512
- Lead Sponsor
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital
- 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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 20
- Parturients with BMI≥50 kg/m2 requesting epidural labor analgesia or undergoing elective cesarean delivery
- contraindication to epidural anesthesia
- allergy or hypersensitivity to lidocaine, bupivacaine or fentanyl
- those with implanted electronic devices.
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Patients having an epidural placed for labour analgesia or anesthesia for cesarean delivery Tsui test Patients with BMI\>=50 who are having an epidural placed may take part in this study. Patients having an epidural placed for labour analgesia or anesthesia for cesarean delivery epidural waveform analysis Patients with BMI\>=50 who are having an epidural placed may take part in this study.
- Primary Outcome Measures
Name Time Method Tsui test motor response: questionnaire 15 minutes Tsui test motor response will be recorded as either: left, right or bilateral. Any increase in current requirement after the test dose will be recorded.
epidural waveform test (catheter) - questionnaire 15 minutes A positive epidural waveform test through the catheter, defined as the presence of a pulsatile waveform observed in synchrony with heart rate: yes or no.
- Secondary Outcome Measures
Name Time Method epidural waveform test (needle) - questionnaire 15 minutes A positive epidural waveform test though the needle, defined as the presence of a pulsatile waveform observed in synchrony with heart rate: yes or no
Tsui test motor response (before test dose): questionnaire 15 minutes Tsui test motor response will be recorded as either: left, right or bilateral.
Tsui test current threshold (baseline) 15 minutes Minimal electrical current required to produce a muscular contraction (mA) at baseline.
Tsui test current threshold (after test dose) 15 minutes Minimal electrical current required to produce a muscular contraction (mA) 5 minutes after the test dose.
Laterality of the Tsui test: questionnaire 15 minutes Laterality of the Tsui test, recorded as: unilateral right or left, or bilateral
Location of muscle group response to Tsui test: questionnaire 15 minutes Muscle group responding to the electrical stimulation: abdominal wall, thigh, lower leg, foot (left or right)
Need for catheter mobilization: questionnaire 15 minutes The need for catheter mobilization, including replacement (at any time after it is placed) will be documented as yes or no. The reason will also be recorded.
Trial Locations
- Locations (1)
Mount Sinai Hospital
🇨🇦Toronto, Ontario, Canada