Related Experiment Video
Updated: Jun 15, 2026

Spinal Sonography for Ultrasound-Guided Lumbar Neuraxial Anesthesia
Published on: January 31, 2025
Evidence basis for ultrasound-guided block characteristics: onset, quality, and duration
Spencer S Liu1, Justin Ngeow, Raymond S John
1Departments of Anesthesiology, Hospital for Special Surgery, Weill College of Medicine of Cornell University, New York, NY 10021, USA. liusp@hss.edu
Background And Objectives:
This systematic review summarizes existing evidence for superior onset, quality, and duration of block for ultrasound (US) guidance versus other techniques for nerve localization.
Methods:
MEDLINE was systematically searched from 1966 to September 2009 for randomized controlled trials (RCTs) comparing US guidance to another technique for peripheral nerve blocks.
Results:
Sixteen RCTs were identified for upper-extremity peripheral nerve blocks and 8 for lower extremity. Jadad scores for quality of RCT ranged from 1 to 5, with a median of 2. For upper-extremity blocks, 9 (60%) of 15 RCTs reported faster onset of block, 4 (25%) of 16 reported better quality of block, and 1 (17%) of 6 reported longer duration of block with US. Only 1 RCT reported that US was inferior in any outcome. For lower-extremity blocks, 5 (71%) of 7 RCTs reported faster onset, 5 (63%) of 8 reported better quality, and none of 3 RCTs reported longer duration of blocks. No RCTs reported that US was inferior in any outcome.
Conclusions:
There is level 1b evidence to make a grade A recommendation that US guidance provides a modest improvement in block onset and quality of peripheral nerve blocks. Ultrasound is rarely inferior to other techniques.
Related Concept Videos
Nondepolarizing (Competitive) Neuromuscular Blockers: Pharmacokinetics
Instead, they are transported by the blood to different tissues. Muscles with a greater blood supply (arteries) and blood flow receive more...
Local Anesthetics: Clinical Application as Intravenous Regional Anesthesia
One of the advantages of...
Depolarizing Blockers: Pharmocokinetics
Local Anesthetics: Clinical Application as Surface, Infiltration, and Conduction Block Anesthesia
Nondepolarizing (Competitive) Neuromuscular Blockers: Pharmacological Actions
Although all competitive neuromuscular blockers are designed...
Depolarizing Blockers: Mechanism of Action
Succinylcholine is the most commonly used depolarizing blocker. Chemically, it constitutes two molecules of acetylcholine joined together by an acetate methyl group. They act on the receptors in the same way as acetylcholine. Because succinylcholine...

