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

NCT07549776 | Completed

• 1 other identifier: 0107-DG-0080-OEAIDE-I
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Spinal anesthesia is the most commonly used anesthetic technique for cesarean section. However, in obese parturients, identification of the optimal puncture site using anatomical landmark palpation can be challenging because of altered anatomy. Preprocedural ultrasound has been proposed as a tool to improve localization of the puncture site and facilitate neuraxial access. This is a prospective comparative study included 100 obese parturients undergoing cesarean section under spinal anesthesia. Participants were allocated to one of two comparison groups according to the puncture site localization technique: a preprocedural ultrasound group and an anatomical landmark palpation group. The primary outcome is the first-attempt success rate, defined as successful cerebrospinal fluid return after the first needle insertion without needle redirection or a new skin puncture. Secondary outcomes include the number of puncture attempts, needle redirections, need for rescue interventions, incidence of paresthesia and vascular puncture during the procedure, and procedural times.

Conditions

Obesity; Cesarean Section

Keywords

Ultrasonography; Spinal anesthesia; Cesarean section; Obesity; Neuraxial anesthesia

Outcome Measures

Primary Outcomes (1)

• First-attempt success rate of spinal anesthesia

  Successful cerebrospinal fluid return after the first needle insertion without redirection.

  During the spinal anesthesia procedure

Secondary Outcomes (7)

• Number of puncture attempts

  During the spinal anesthesia procedure

• Number of needle redirections

  During the spinal anesthesia procedure

• Need for rescue intervention

  During the spinal anesthesia procedure

• Incidence of paresthesia

  During the spinal anesthesia procedure

• Incidence of vascular puncture

  During the spinal anesthesia procedure

Study Arms (2)

Ultrasound-guided group

ACTIVE COMPARATOR

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

Procedure: Ultrasound-guided preprocedural marking

Landmark-based group

ACTIVE COMPARATOR

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

Procedure: Landmark-based palpation

Interventions

Ultrasound-guided preprocedural marking PROCEDURE

Preprocedural ultrasound is used to identify and mark the optimal puncture site before spinal anesthesia.

Ultrasound-guided group

Landmark-based palpation PROCEDURE

The puncture site is identified using anatomical landmark palpation before spinal anesthesia.

Landmark-based group

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

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

Sponsors & Collaborators

• Instituto Nacional Materno Perinatal, Peru: lead

Study Sites (1)

National Maternal and Perinatal Institute

Lima, Lima Province, 15001, Peru

Location

Related Publications (4)

• Khoo AK, Huynh A, Pelecanos A, Eley VA. Does preprocedural ultrasound prior to lumbar neuraxial anesthesia or analgesia increase first-pass success in adults with obesity? A systematic review. Health Sci Rep. 2024 Nov 6;7(11):e70039. doi: 10.1002/hsr2.70039. eCollection 2024 Nov.

  PMID: 39507679 BACKGROUND

• Zhang Y, Peng M, Wei J, Huang J, Ma W, Li Y. Comparison of ultrasound-guided and traditional localisation in intraspinal anesthesia: a systematic review and network meta-analysis. BMJ Open. 2023 Nov 2;13(11):e071253. doi: 10.1136/bmjopen-2022-071253.

  PMID: 37918920 BACKGROUND

• Li M, Ni X, Xu Z, Shen F, Song Y, Li Q, Liu Z. Ultrasound-Assisted Technology Versus the Conventional Landmark Location Method in Spinal Anesthesia for Cesarean Delivery in Obese Parturients: A Randomized Controlled Trial. Anesth Analg. 2019 Jul;129(1):155-161. doi: 10.1213/ANE.0000000000003795.

  PMID: 30234528 BACKGROUND

• Perlas A, Chaparro LE, Chin KJ. Lumbar Neuraxial Ultrasound for Spinal and Epidural Anesthesia: A Systematic Review and Meta-Analysis. Reg Anesth Pain Med. 2016 Mar-Apr;41(2):251-60. doi: 10.1097/AAP.0000000000000184.

  PMID: 25493689 BACKGROUND

MeSH Terms

Conditions

Obesity

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Eddisson R Quispe Pilco, MD

  National Maternal and Perinatal Institute

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Masking Details: Due to the nature of the intervention, blinding of the operators was not feasible.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Staff Anesthesiologist, Department of Anesthesia

Model Details: Participants were prospectively allocated to one of two comparison groups according to the puncture site localization technique (preprocedural ultrasound marking or anatomical landmark palpation) before spinal anesthesia.

Study Record Dates

• First Submitted: April 9, 2026
• First Posted: April 24, 2026
• Study Start: July 1, 2025
• Primary Completion: January 1, 2026
• Study Completion: January 1, 2026
• Last Updated: July 7, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: Beginning 3 months after publication and ending 12 months after publication
• Access Criteria: Access will be granted to researchers who provide a methodologically sound proposal. Proposals should be directed to the corresponding author via email. Data will be shared after approval of the proposal and signing of a data access agreement.

Locations

PE (1)