IVC ultrasound: Difference between revisions
Kghaffarian (talk | contribs) (expanded background) |
Kghaffarian (talk | contribs) (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 | *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 | ||
* | *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