Ultrasound-guided Versus Landmark-based Spinal Anesthesia in Obese Parturients Undergoing Cesarean Section (USLMCSEOB)

Instituto Nacional Materno Perinatal, Peru

Status: Completed

Conditions: Cesarean Section; Obesity

Treatments: Procedure: Landmark-based palpation; Procedure: Ultrasound-guided preprocedural marking

Study type: Interventional

Funder types: Other

Identifiers

NCT07549776

0107-DG-0080-OEAIDE-I

Details and patient eligibility

About

Spinal anesthesia is the most commonly used technique for cesarean section. However, in obese parturients, identification of the optimal puncture site using anatomical landmark palpation can be challenging due to altered anatomy. Ultrasound has been proposed as a tool to improve localization of the puncture site.

This study is a prospective randomized controlled trial including 100 obese parturients undergoing cesarean section under spinal anesthesia. Participants are randomly assigned to one of two groups: an ultrasound group, in which the puncture site is identified using preprocedural ultrasound, and a landmark group, in which the puncture site is determined using anatomical landmark palpation.

The primary outcome is the first-attempt success rate. Secondary outcomes include the number of attempts, needle redirections, need for rescue interventions, incidence of adverse events during puncture, and procedural times.

Full description

This prospective randomized controlled trial aims to evaluate the effectiveness of preprocedural ultrasound-guided marking compared with the conventional landmark palpation technique for spinal anesthesia in obese parturients undergoing cesarean section.

A total of 100 parturients with a body mass index (BMI) ≥ 30 kg/m² are randomly assigned to either the ultrasound group or the landmark group. In the ultrasound group, the puncture site is identified using preprocedural ultrasound to determine the optimal intervertebral space and needle insertion trajectory. In the landmark group, the puncture site is determined using anatomical landmarks.

The primary outcome is the first-attempt success rate, defined as successful cerebrospinal fluid return without needle redirection. Secondary outcomes include the number of puncture attempts, needle redirections, need for rescue interventions, incidence of adverse events (paresthesia and vascular puncture), and procedural times (site identification time, puncture time, and total procedural time).

This study aims to determine whether ultrasound guidance improves the performance and safety of spinal anesthesia in obese parturients.

Enrollment: 100 patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age ≥ 18 years
• Pregnant women undergoing cesarean section
• Body mass index (BMI) ≥ 30 kg/m² at the time of cesarean section
• Scheduled for cesarean section under spinal anesthesia

Exclusion criteria

• Congenital spinal deformities
• History of spinal surgery
• Coagulopathy
• Infection at the puncture site
• Allergy to local anesthetics
• Emergency cesarean section (NICE category 1)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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100 participants in 2 patient groups

Ultrasound-guided group

Active Comparator group

Description:

Preprocedural ultrasound was used to identify and mark the optimal puncture site in obese parturients undergoing cesarean section (n = 50).

Treatment:

Procedure: Ultrasound-guided preprocedural marking

Landmark-based group

Active Comparator group

Description:

The puncture site was identified using anatomical landmark palpation in obese parturients undergoing cesarean section (n = 50)

Treatment:

Procedure: Landmark-based palpation