Tips and Tricks
- A small amount of local anesthetic is extremely useful in an awake patient to mitigate the pain caused by needle puncture and sheath placement
- Spasmolytic cocktail is typically composed of two vasodilators and heparin
- 200-400 mcg of nitroglycerin
- 2.5-5.0 mg of verapamil
- 2,000 units of heparin
- Verapamil is acidic and will cause uncomfortable feeling, thus needs to be diluted before injecting
- Heparin dose can be adjusted depending on the purpose of the angiography
- When injecting the anesthetics, make sure all the air in the syringe is purged out, as subcutaneous air could severely interfere with the ultrasound imaging and obscure the artery.
- When injecting a spasmolytic cocktail into an awake patient, make sure to inform the patient and hold the patient's arm in place to prevent sudden movement of the arm due to discomfort.
Ultrasound-Guided Radial Artery Puncture
A: Frequently, there is an accompanying vein (red arrow) running alongside the radial artery (yellow arrowhead).
B: Applying gentle pressure on the wrist will cause the vein to collapse, while the artery remains full with pulsations. Observe the slight "upward shift" of both the collapsed vein and the artery (closer to the skin).
The aberrant right subclavian artery/lusorian artery (red arrow) which can be easily ascertained on CTA neck, is considered a relative contraindication for radial access. Yellow arrow: right CCA. Blue arrow: left CCA. Green arrow: left subclavian artery. Orange arrow: right VA. Pink star: esophagus. White diamond: trachea. (Unfortunately, this is not an ideal study due to the suboptimal timing and contrast contamination in the adjacent veins.)
Radial Access via Aberrant Right Subclavian Artery | neuroangio.org ↩︎