Rad

Peak Systolic Velocity

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Peak Systolic Velocity

  • Definitions
  1. Peak Systolic Velocity (PSV)
    1. Doppler Ultrasound measurement of vessel flow
    2. Measures the tallest peaks (spikes of high flow) on waveform doppler
  • Indications
  1. Various uses in specialty, tertiary medicine
  2. Cardiac Arrest Resuscitation
    1. Evaluation of femoral artery PSV to determine if adequate perfusion in ROSC
  • Techqnique
  1. Select pulse wave doppler on the Ultrasound machine
  2. Position the Ultrasound probe
    1. Place linear probe over vessel of interest, with the vessel in cross-section (transverse)
    2. Two line paths intersect (lines drawn automatically by machine)
      1. One vertical
      2. One at 60 degrees
  3. Once positioned, press the pulse wave doppler button
    1. Begins recording a tracing of vessel pressure with intermittent spikes
  4. Freeze the image
    1. Using Ultrasound measurements to select Velocity (or Vel)
    2. Select the tallest waveform/spike
    3. Velocity (cm/s) will be displayed on screen
  • Interpretation
  1. Peak Systolic Velocity >20 cm/s correlates with systolic Blood Pressure >=60 mmHg