Pre-procedural Ultrasound Techniques Versus Conventional Landmark Technique of Spinal Anesthesia in Elderly Patients

Summary

Traditionally, spinal anesthesia is performed using the palpation of bony landmark to identify the level and point of entry of the spinal needle. Recently, ultrasound imaging has become an increasingly popular procedure among anesthesiologists to guide neuraxial blockade. Most of the studies on pre-procedural ultrasound-guided neuraxial techniques are limited to a midline approach using a transverse median views. The parasagittal oblique view consistently offers better ultrasound view of the neuraxis compared to the transverse median view. However, it is still not evident whether these superior parasagittal oblique views will lead to an easier paramedian needle insertion. In the literature, there are no studies directly comparing the US-guided paramedian approach using the parasagittal oblique (PSO) view, the US-guided midline approach using the transverse median view, and the conventional landmark midline approach to perform spinal anesthesia in the elderly patients, in particular for the teaching of novice anesthesia residents.

Conditions

• Anesthesia

Interventions

OTHER

Landmark technique

The site of needle insertion will be determined via manual palpation. A line joining the superior aspect of the iliac crests posteriorly (Tuffier's line') will be used as a surface landmark for the L4 vertebral body. The midline will be established by palpation of the tips of the spinous processes, and the site of needle insertion will be marked on the patient's skin. The interspace that appears widest, based on manual palpation, will be chosen for the first attempt. If the first attempt is unsuccessful, further attempts can be made at the same interspace or another interspace.

OTHER

Ultrasound-guided paramedian technique

The transducer will be applied in the parasagittal plane and the intervertebral levels will be identified by counting upwards from the sacrum (continuous hyperechoic line). The probe will then be angled obliquely to obtain a PSO view. The locations of the interlaminar spaces will be identified by visualizing the ligamentum flavum-dura mater complex and the posterior aspect of the vertebral body. The angulation at which the ligamentum flavum-dura mater complex and posterior vertebral body are best visualized will be considered the optimal angle for needle insertion and clearly communicated to the operator. The interlaminar space will be centered on the ultrasound screen and a skin marker will be used to make a mark on the patient's back at the middle of the ultrasound probe.

OTHER

Ultrasound-guided midline technique

The transducer will be applied in the parasagittal plane, and after identification of the intervertebral levels, the probe will be rotated 90 degree to obtain the TM view. The transducer is moved in a cephalad-caudad direction between the spinous processes of L2 and L5 vertebra. The probe will be tilted slightly up and down to ensure a sufficient echogenic window at the selected intervertebral space. A skin marker will be used to make a mark on the patient's back at the middle of the ultrasound probe. The angle at which the ligamentum flavum-dura mater complex and the posterior aspect of the vertebral body are best visualized will be noted

Sponsors & Collaborators

• American University of Beirut Medical Center

  lead OTHER

Principal Investigators

• Sahar Siddik-Sayyid, MD · American University of Beirut Medical Center

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

60 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2015-11-30

Primary Completion

2018-01-31

Completion

2018-01-31

Countries

• Lebanon

Study Locations