IVC ultrasound
Background
- Inferior vena cava ultrasound measurements
- >50% collapse correlates with CVP <8
- Unclear if able to use in intubated patients
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