The Impact of Ultrasound-Guided Spinal Anesthesia

NCT ID: NCT07327801

Last Updated: 2026-01-08

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 136 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-02-01
• Study Completion Date: 2025-07-30

Brief Summary

Neuraxial anesthesia is a commonly employed technique for subumbilical surgical procedures due to its effectiveness and safety profile. The advent of ultrasound technology has introduced the possibility of visualizing anatomical landmarks in real time, thereby facilitating more accurate and potentially safer subarachnoid punctures. This study aims to compare conventional spinal anesthesia, based on palpation, with ultrasound-guided spinal anesthesia, focusing on procedural ease and overall facilitation.

it's a prospective, single-center, randomized, single-blind study. We included patients aged 18 years or older, classified as ASA I or II, scheduled for elective surgery, and who provided written informed consent. Exclusion criteria included failed subarachnoid puncture, conversion to general anesthesia, or the occurrence of major intraoperative complications such as vasovagal episodes or cardiac rhythm disturbances. Participants were randomly assigned, based on a randomization table, into two groups: Group1 (traditional technique), in which spinal anesthesia was performed using the conventional palpation-based method for space localization; and Group2 (ultrasound-guided technique), in which spinal anesthesia was performed under real-time ultrasound guidance. The primary outcome was the total procedure time, measured in seconds from the end of skin antisepsis to the initiation of subarachnoid injection. Secondary outcomes included the number of puncture attempts, the number of needle redirections within the same interspace, the occurrence of procedural incidents, and postoperative complaints such as radicular pain, osseous contact pain, intraoperative paresthesias, and traumatic punctures.

Conditions

Ultrasound Guidance; Spinal Anesthesia; Procedural Performance; Conventional Palpation Technique

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Conventional spinal anesthesia

The operator began by palpating the posterior superior iliac spines to mentally determine the Tuffier's line, which roughly corresponds to the L4-L5 intervertebral space. The spinous processes were then palpated to precisely locate the targeted intervertebral space. The needle was subsequently inserted until cerebrospinal fluid return was obtained, and the anesthetic agent was administered slowly

Group Type: ACTIVE_COMPARATOR

Conventional spinal anesthesia

Intervention Type: DEVICE

The spinous processes were then palpated to precisely locate the targeted intervertebral space

Ultrasound-guided spinal anesthesia

The operator set up the sterile equipment, which included an ultrasound machine equipped with a low-frequency convex probe (2-5 MHz). The probe, previously disinfected, was covered with a sterile sheath containing sterile coupling gel.

First, the transducer was positioned in a paramedian sagittal plane, placed 1-2 cm lateral to the spinous processes. The sacrum was identified as a flat, hyperechoic structure producing a marked acoustic shadow, serving as the starting landmark for identifying successive lumbar intervertebral spaces. By gradually sliding the transducer cephalad, the vertebral laminae appeared as hyperechoic lines alternating with their posterior acoustic shadows. The interlaminar spaces, located between two adjacent laminae, form true acoustic windows that allow visualization of the underlying neuraxial structures.

The exploration continued until the intervertebral space deemed optimal for puncture was identified. The probe was then switched to a midline posit

Group Type: ACTIVE_COMPARATOR

Ultrasound-guided spinal anesthesia

Intervention Type: DEVICE

A combined sequence was used, beginning with a longitudinal paramedian scan, followed by a 90-degree rotation to obtain a transverse interspinous view. This allowed for the identification of the spinal canal, after which the puncture was performed using dynamic, out-of-plane guidance

Interventions

Conventional spinal anesthesia

The spinous processes were then palpated to precisely locate the targeted intervertebral space

Intervention Type: DEVICE

Ultrasound-guided spinal anesthesia

A combined sequence was used, beginning with a longitudinal paramedian scan, followed by a 90-degree rotation to obtain a transverse interspinous view. This allowed for the identification of the spinal canal, after which the puncture was performed using dynamic, out-of-plane guidance

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Patients aged 18 years or older.
• Classified as American Society of Anesthesiologists (ASA) physical status I or II.
• Scheduled for elective surgery under spinal anesthesia.
• Provided written informed consent.

Exclusion Criteria

• Failed subarachnoid puncture.
• Conversion to general anesthesia.
• Occurrence of major intraoperative complications (e.g., vasovagal episodes, cardiac rhythm disturbances).

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Military Hospital of Tunis

OTHER

Sponsor Role: lead

Responsible Party

askrihaythem

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Military Hospital of Tunis

Tunis, , Tunisia

Countries

Tunisia

Other Identifiers

54/2024/clpp/militaryhosptunis

Identifier Type: -

Identifier Source: org_study_id