The diameter of the IVC should be measured at end-expiration 1-3 cm before it merges with the RA just proximal to the hepatic vein
Measurement is done on a 2D image or on an M-mode scan
Video showing the IVC target view
Starting from the sub-costal short axis view of the IVC and abdominal aorta followed by counterclockwise rotation of the transducer until a long axis view of the IVC is present on the screen
– The reference diameter is the largest diameter
– Measure as perpendicular to the vessel walls as possible
– Measure at end-expiration
The target view is the IVC long axis image corresponding to the scanning plane indicated on the torso in the picture
As the IVC transects the liver, liver tissue will appear both in the near and far fields
By convention, the orientation marker in cardiac ultrasound is directed cranially
The structures identified in FATE position 1, IVC view
Identify:
– Liver
– RA: Right atrium
– IVC: Inferior vena cava
– Lung tissue
To avoid mistaking the abdominal aorta for the IVC:
1) Identify the entry point of the IVC into the RA
2) Pulsation of the vessel will more likely suggest aortic imaging
In radiology and emergency medicine it is general practice to display the IVC as a mirror image
Notice the orientation marker (yellow “V”) is now on the left side of the screen
Familiarize yourself with both ways of presentation
The probe is placed on the skin subcostally
The OM is orientated cranially
The OI is on the right side of the screen
The right atrium will be displayed to the right and the IVC to the left and the liver on top of the screen
By convention, in cardiac ultrasound the orientation indicator is placed on the right side of the screen
Image obtained from the subcostal 4 chamber view
– Hold the transducer as a screwdriver, prone
– Place it subcostally, slightly to the right of the midline
– OM should be directed towards the patient’s left
– To achieve the correct anatomical alignment, rotate the transducer approx. 20
Memorize the target IVC image before beginning the examination
A schematic drawing of IVC is found at the upper left corner of the extended views on the FATE card
Download the FATE-card here: https://test.usabcd.org/fate-card
Inferior vena cava is another useful view obtained from position 1
The view is suitable for a quick evaluation of:
– IVC dimension
– IVC dynamics with respiration
– Placement of umbilical catheter in neonates
– IVC dynamics for the optimization of fluid responsiveness
