Ultrasound Versus Palpation for Epidural Catheterization

Study Overview
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Brief Summary
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The study will assess the benefit of using spinal ultrasound before epidural catheter insertion compared to the conventional palpation technique in women undergoing cesarean section.

Detailed Description
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The study will compare the ultrasound-assisted and the conventional palpation techniques for epidural catheterization as a component of combined spinal-epidural anesthesia for cesarean section. Participants will be randomly assigned into 2 equal groups. In the ultrasound group: Preprocedure lumbar spinal ultrasound will be performed before epidural catheterization. In the palpation group: Conventional technique of landmark palpation will be used.

Official Title
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Comparison Between Ultrasound-assisted and Conventional Palpation Techniques for Epidural Catheterization Before Cesarean Section

Conditions
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Epidural Anesthesia, Spinal Ultrasound

Intervention / Treatment
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* Procedure: Double-space combined spinal-epidural anesthesia
* Radiation: Preprocedure spinal ultrasound
* Radiation: Sham ultrasound procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists class I or II. Full term parturients scheduled for elective cesarean delivery under combined spinal-epidural anesthesia. Exclusion Criteria: Body mass index ≥ 35 kg/m2. Patients having any contraindication to neuraxial anesthesia (Refusal of the procedure, Coagulopathy, Uncorrected hypovolemia, Increased intracranial pressure, Local skin infection). Marked spinal deformity or previous spinal surgery. Unpalpable anatomical landmarks. Emergent situations.

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Palpation<br>Double-space combined spinal-epidural anesthesia, Sham ultrasound procedure | Procedure: Double-space combined spinal-epidural anesthesia<br>* Epidural space identification in Lumbar 2-3 or 3-4 space using loss of resistance to air technique with 18-gauge Tuohy needle, then threading a 20-gauge multi-orifice epidural catheter 4-5 cm into the epidural space. Spinal anesthesia administration in an appropriate lower intervertebral space with intrathecal bupivacaine 12.5 mg and fentanyl 10 mcg through a 27-gauge spinal needle.<br>Radiation: Sham ultrasound procedure<br>* Applying the ultrasound probe on the patient's back while the ultrasound machine is on the freeze position.Then skin markings relying on landmark palpation are made identifying 2 intervertebral spaces.<br>|
| Experimental: Ultrasound<br>Double-space combined spinal-epidural anesthesia, Preprocedure spinal ultrasound | Procedure: Double-space combined spinal-epidural anesthesia<br>* Epidural space identification in Lumbar 2-3 or 3-4 space using loss of resistance to air technique with 18-gauge Tuohy needle, then threading a 20-gauge multi-orifice epidural catheter 4-5 cm into the epidural space. Spinal anesthesia administration in an appropriate lower intervertebral space with intrathecal bupivacaine 12.5 mg and fentanyl 10 mcg through a 27-gauge spinal needle.<br>Radiation: Preprocedure spinal ultrasound<br>* Lumbar spinal ultrasound using the 2-5 MHz curved probe, performed in both the longitudinal and transverse planes for identification of the appropriate intervertebral spce, estimation of the depth to the epidural space, and noting the proper angle for subsequent needle insertion. Then skin markings relying on the ultrasound procedure are made identifying 2 intervertebral spaces.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of successful epidural catheterization at the first needle pass | Needle pass includes any forward advancement of the Tuohy needle. | 24 hours after delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of successful epidural catheterization at the first skin puncture | Skin puncture includes any separate skin puncture by the Tuohy needle. | 24 hours after delivery | 
| Number of needle passes required for successful epidural catheterization |  | 24 hours after delivery | 
| Number of skin punctures required for successful epidural catheterization |  | 24 hours after delivery | 
| Time of the epidural catheterization procedure | From the initial Tuohy needle insertion through the skin to the completion of the threading of the epidural catheter. | 24 hours after delivery | 
| Patient satisfaction (5-point scale) | 5-point scale | 24 hours after delivery | 
| Rate of Inadvertent dural puncture |  | 24 hours after delivery | 
| Rate of Inadvertent vascular puncture |  | 24 hours after delivery | 
| Rate of Failed block | Complete failure of epidural catheter after 2 doses of epidural injection of 10 ml bupivacaine 0.25% and fentanyl 20 mcg administered 20 min apart. | At the first request of analgesia | 
| Unilateral / Patchy block (Assessed by pinprick) | Assessed by pinprick after 20 min of epidural injection of 10 ml bupivacaine 0.25% and fentanyl 20 mcg | At the first request of analgesia | 
| Rate of Back pain |  | 24 hours after delivery |