Difference between revisions of "IVC ultrasound"

(expanded background)
(clarified techniques, added info about mmode)
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==Technique==
 
==Technique==
*Use phased array probe
+
*Use curvilinear (abdominal) probe or phased array (cardiac) probe
*In subxyphoid cardiac view (epigastric), fan probe inferiorly to view the IVC draining into the right atrium
+
*In subxyphoid cardiac view (epigastric), fan probe laterally to view the IVC draining into the right atrium
 
**may start with subxyphoid view, place right atrium in center of screen and rotate probe 90 degrees clockwise to find IVC
 
**may start with subxyphoid view, place right atrium in center of screen and rotate probe 90 degrees clockwise to find IVC
*In the RUQ, slide the probe posteriorly to view the IVC draining into the right atrium
+
*use M-mode to measure IVC collapse during inspiration
  
 
==Measurements==
 
==Measurements==

Revision as of 23:06, 5 March 2015

Background

  • Inferior vena cava measurement by ultrasound to estimate volume status
  • Measure both absolute diameter of IVC and percent collapse during inspiration of spontaneously breathing patients
  • can use as a dynamic assessment after intervention (giving fluids)
  • Unclear if applicable to intubated patients

Technique

  • Use curvilinear (abdominal) probe or phased array (cardiac) probe
  • In subxyphoid cardiac view (epigastric), fan probe laterally to view the IVC draining into the right atrium
    • may start with subxyphoid view, place right atrium in center of screen and rotate probe 90 degrees clockwise to find IVC
  • use M-mode to measure IVC collapse during inspiration

Measurements

IVC  % Collapse during inspiration^ CVP
<1.5cm >50% 0-5
1.5-2.5cm >50% 5-10
1.5-2.5cm <50% 10-15
>2.5cm Little phasicity 15-20

^Measure ~2cm from IVC/RA junction

  • Can ask patient to sniff or valsalva to evaluate collapse

See Also