"Ultrasound vs. Landmark Technique for Spinal Anesthesia in Obese Women Undergoing Cesarean Section"

NCT07601542 | Completed

• 1 other identifier: 5294
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate whether the ultrasound-assisted technique improves the accuracy and safety of spinal anesthesia compared to the traditional landmark technique in obese women undergoing a cesarean section. The main questions it aims to answer are: Does the ultrasound-assisted technique reduce the number of needle attempts required for successful spinal anesthesia? Does the ultrasound-assisted technique decrease the incidence of post-dural puncture headache (PDPH) and chronic low back pain at the needle insertion site? Does the ultrasound-assisted technique reduce procedure time compared to the landmark technique? Participants will: Receive spinal anesthesia using either the ultrasound-assisted technique or the traditional landmark technique for cesarean section. Be monitored for the number of needle attempts, procedure time, and any post-operative complications such as PDPH or low back pain. Follow up for three months after the procedure to assess any long-term effects, including chronic low back pain and quality of life.

Conditions

Cesarean Section; Obese Parturient; Ultrasound Guided Subarachnoid Block

Keywords

Obese parturient; Cesarean Section; Subarachnoid block

Outcome Measures

Primary Outcomes (1)

• Number of Needle Attempts for Successful Subarachnoid Block

  his is the key measure in your study, as it directly assesses the effectiveness of the two anesthesia techniques (ultrasound-assisted vs. landmark-guided) in achieving successful spinal anesthesia. Fewer needle attempts would indicate a higher success rate and a more efficient technique, making it the most critical outcome for evaluating the interventions.

  During the procedure, until successful spinal needle placement

Secondary Outcomes (5)

• Needle Insertion Site Accuracy in landmark technique group

  Immediately after transferring the participants in the recovery room

• Procedure Duration in minutes

  During procedure

• Incidence of Post-Dural Puncture Headache (PDPH)

  Postoperative period (up to 72 hours)

• Chronic Low Back Pain at Needle Insertion Site

  3 months post-procedure

• Impact of Chronic Low Back Pain on Quality of Life

  3 months post-procedure

Study Arms (2)

Group A: Landmark-Guided Spinal Anesthesia

ACTIVE COMPARATOR

In this arm, participants will receive subarachnoid block using the traditional landmark technique for spinal anesthesia. The L3-L4 or L4-L5 intervertebral space will be identified by palpating the iliac crests to locate Tuffier's line, and the spinal needle will be inserted based on these bony landmarks. The anesthetic agents administered will be 0.5% hyperbaric bupivacaine (10 mg) and 25 μg fentanyl (0.5 mL). The procedure will be performed by experienced anesthesiologists.

Procedure: Landmark-Guided Spinal Anesthesia

Group B: Ultrasound-Assisted Spinal Anesthesia

EXPERIMENTAL

In this arm, participants will receive subarachnoid block using the ultrasound-assisted technique. A low-frequency (2-5 MHz) curvilinear probe will be used to visualize the lumbar spine and identify the intervertebral space. The correct intervertebral space (L3-L4 or L4-L5) will be identified using real-time ultrasound imaging. The anesthetic agents administered will be 0.5% hyperbaric bupivacaine (10 mg) and 25 μg fentanyl (0.5 mL). This procedure will also be performed by experienced anesthesiologists with expertise in neuraxial ultrasound.

Procedure: Ultrasound-Assisted Spinal Anesthesia

Interventions

Landmark-Guided Spinal Anesthesia PROCEDURE

This intervention involves the use of traditional anatomical landmarks to locate the correct intervertebral space for performing subarachnoid block (SAB). The anesthesiologist identifies the L3-L4 or L4-L5 intervertebral space by palpating the iliac crests and using Tuffier's line as a reference. A 25G Quincke needle is used for SAB, and 0.5% hyperbaric bupivacaine with 25 μg fentanyl is administered. This technique is the standard approach used in many clinical settings for spinal anesthesia.

Group A: Landmark-Guided Spinal Anesthesia

Ultrasound-Assisted Spinal Anesthesia PROCEDURE

This intervention utilizes ultrasound guidance to identify the correct intervertebral space for performing subarachnoid block (SAB). A low-frequency (2-5 MHz) curvilinear ultrasound probe is used to visualize the lumbar spine in real-time, ensuring precise identification of the L3-L4 or L4-L5 intervertebral space. The anesthesiologist places the needle based on ultrasound images that show the anatomical structures, such as the spinous processes and interlaminar spaces. The same anesthetic agents (0.5% hyperbaric bupivacaine and 25 μg fentanyl) are administered through a 25G Quincke needle for SAB.

Group B: Ultrasound-Assisted Spinal Anesthesia

Eligibility Criteria

• Sex: female
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Elective caesarean section
• ASA physical status: Ⅱ
• Obese parturient (BMI ≥ 30.1 kg/m²)

You may not qualify if:

• Allergic to local anaesthetic (0.5% Bupivacaine hydrochloride with 8% Dextrose and 2 % Lidocaine hydrochloride USP)
• Preexisting neurological deficit by clinical examination
• Any contraindication to SAB
• History of scoliosis or spinal instrumentation
• Allergy to ultrasound transmission gel

Sponsors & Collaborators

• Bangladesh Medical University: lead

Study Sites (1)

Bangladesh Medical University

Dhaka, 1000, Bangladesh

Location

Related Publications (12)

• Wattanaruangkowit P, Lakchayapakorn K. The position of the lumbar vertebrae in relation to the intercrestal line. J Med Assoc Thai. 2010 Nov;93(11):1294-300.

  PMID: 21114209 BACKGROUND

• Srinivasan KK, Leo AM, Iohom G, Loughnane F, Lee PJ. Pre-procedure ultrasound-guided paramedian spinal anaesthesia at L5-S1: Is this better than landmark-guided midline approach? A randomised controlled trial. Indian J Anaesth. 2018 Jan;62(1):53-60. doi: 10.4103/ija.IJA_448_17.

  PMID: 29416151 BACKGROUND

• Sahin T, Balaban O, Sahin L, Solak M, Toker K. A randomized controlled trial of preinsertion ultrasound guidance for spinal anaesthesia in pregnancy: outcomes among obese and lean parturients: ultrasound for spinal anesthesia in pregnancy. J Anesth. 2014 Jun;28(3):413-9. doi: 10.1007/s00540-013-1726-1. Epub 2013 Oct 20.

  PMID: 24141882 BACKGROUND

• Kurdi MS, Agrawal P, Thakkar P, Arora D, Barde SM, Eswaran K. Recent advancements in regional anaesthesia. Indian J Anaesth. 2023 Jan;67(1):63-70. doi: 10.4103/ija.ija_1021_22. Epub 2023 Jan 21.

  PMID: 36970484 BACKGROUND

• Khan MA, Gupta M, Sharma S, Kasaudhan S. A comparative study of ultrasound assisted versus landmark technique for combined spinal-epidural anaesthesia in patients undergoing lower limb orthopaedic surgery. Indian J Anaesth. 2022 Apr;66(4):272-277. doi: 10.4103/ija.ija_775_21. Epub 2022 Apr 20.

  PMID: 35663223 BACKGROUND

• Gayathri B, Swetha Ramani CK, Urkavalan K, Pushparani A, Rajendran A. Comparison of the time taken for subarachnoid block using ultrasound-guided method versus landmark technique for cesarean section - A randomized controlled study. J Anaesthesiol Clin Pharmacol. 2021 Apr-Jun;37(2):205-209. doi: 10.4103/joacp.JOACP_35_20. Epub 2021 Jul 15.

  PMID: 34349367 BACKGROUND

• Forozeshfard M, Jahan E, Amirsadat J, Ghorbani R. Incidence and Factors Contributing to Low Back Pain in the Nonobstetrical Patients Operated Under Spinal Anesthesia: A Prospective 1-Year Follow-Up Study. J Perianesth Nurs. 2020 Feb;35(1):34-37. doi: 10.1016/j.jopan.2019.06.008. Epub 2019 Oct 18.

  PMID: 31635919 BACKGROUND

• Bhardwaj D, Thakur L, Sharma S, Rana S, Gupta B, Sharma C. Comparative evaluation of three techniques for paramedian subarachnoid block: Point-of-care preprocedural ultrasound assisted, real-time ultrasound guided and landmark based. Indian J Anaesth. 2022 Mar;66(Suppl 2):S102-S107. doi: 10.4103/ija.ija_373_21. Epub 2022 Mar 25.

  PMID: 35601040 BACKGROUND

• Betran AP, Ye J, Moller AB, Zhang J, Gulmezoglu AM, Torloni MR. The Increasing Trend in Caesarean Section Rates: Global, Regional and National Estimates: 1990-2014. PLoS One. 2016 Feb 5;11(2):e0148343. doi: 10.1371/journal.pone.0148343. eCollection 2016.

  PMID: 26849801 BACKGROUND

• Bajwa SJ, Bajwa SK. Anaesthetic challenges and management during pregnancy: Strategies revisited. Anesth Essays Res. 2013 May-Aug;7(2):160-7. doi: 10.4103/0259-1162.118945.

  PMID: 25885826 BACKGROUND

• At A, So O. Failed spinal anaesthesia for caesarean section. J West Afr Coll Surg. 2011 Oct;1(4):1-17.

  PMID: 25452968 BACKGROUND

• Ansari T, Yousef A, El Gamassy A, Fayez M. Ultrasound-guided spinal anaesthesia in obstetrics: is there an advantage over the landmark technique in patients with easily palpable spines? Int J Obstet Anesth. 2014 Aug;23(3):213-6. doi: 10.1016/j.ijoa.2014.03.001. Epub 2014 Mar 12.

  PMID: 24768303 BACKGROUND

Related Links

• Related Info

Study Officials

• AKM Akhtaruzzaman, MD

  Bangladesh Medical University

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: May 8, 2026
• First Posted: May 22, 2026
• Study Start: February 1, 2025
• Primary Completion: August 30, 2025
• Study Completion: November 30, 2025
• Last Updated: May 22, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

BA (1)