Ultrasound Regional Flashcards
Advantages
- ability to see __ and __ of LA
- ability to measure __ to the nerves
- __ onset of sensory loss
- __ volume of LA
- no discomfort of __ __
Location and spread Distance Faster Less Nerve stim
USG resulted in __ procedure time, and __ block duration
Shorter, longer
Ultrasound frequencies between __-__ __
Higher number means __ __ lower number means __ __
2-15 MHz
Finer resolution, greater depth
Acoustic impedance
Resistance of tissue to absorption of ultrasound
Differences in this create reflective interfaces
Reflection occurs when what, depends on what
Ultrasound strikes 2 diff media
Texture of surface
Reverberation occurs with what
Multiple reflections from closely spaced interfaces
Absorption
Conversion of ultrasound energy to other forms of energy
Depth, measured in what
Distance away from probe, cm
Scattering
When sound wave strikes small irregular shaped structures and causes artifact
Shadowing
Reduction of ultrasound energy lying below solid objects
Echogenicity
Ability to reflect or transmit ultrasound waves in context to surrounding tissue
Anechoic
Doppler what Bart stands for
Black on screen
Detects blood flow, blue away red towards
Mode: penetrating means what, resolution means what
Depth control
- increased depth does what to image
- try to use what
Deep, superficial
Reduces width
Most superficial setting
Gain control
Adjusts what of signal
__ or __ image
Too much amplifies __
Amplification
Brighter or darker
Artifact
Color gain does what
Increase or reduce color artifact for identifying vessels
