Difference between revisions of "IVC ultrasound"

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== References ==
 
== References ==
 
Dawson, M. Mallin, M. Introduction To Bedside Ultrasound: Volumes 1 and 2.Emergency Ultrasound Solutions. 2012 Inkling File
 
Dawson, M. Mallin, M. Introduction To Bedside Ultrasound: Volumes 1 and 2.Emergency Ultrasound Solutions. 2012 Inkling File
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[[Category:Cards]] [[Category:Rads]]
 
[[Category:Cards]] [[Category:Rads]]

Revision as of 14:55, 7 March 2015

Background

  • Though contriversal, IVC measurement by ultrasound can estimate volume status and fluid responsiveness
    • There is moderate evidence to support that IVC diameter is consistently low in hypovolemia vs euvolemia[1]
    • It is suggested that IVC change can estimate fluid responsiveness with a Sn 0.78 and Sp 0.86[2]
  • 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 or estimation can be made in 2D with IVC in longitudinal axis

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

References

Dawson, M. Mallin, M. Introduction To Bedside Ultrasound: Volumes 1 and 2.Emergency Ultrasound Solutions. 2012 Inkling File

  1. Dipti A, et al. Role of inferior vena cava diameter in assessment of volume status: a meta-analysis. AJEM. 2012; 30:1414-1419.
  2. Zhang Z, et al. Ultrasonographic measurement of the respiratory variation in the inferior vena cava diameter is predictive of fluid responsiveness in critically ill patients: systematic review and meta-analysis. Ultrasound Med Biol. 2014. May; 40(5):845-53.