So take a look at this:
I’m sure most experienced bedside sonographers come across this all the time. For those who are starting out, and until now have just been looking at size and variation, take a second to look at the flow. You can actually see the flow stop and start, which tells you your cardiac output is bad. It could be bad because of the RV, the LV, the pericardium, the tension pneumothorax, anything, but it’s bad. So just in case you were only gonna look at the IVC, keep looking! You will find something abnormal downstream, perhaps that you can do something about (not fluids, though).
I have seen this disappear and clear up with – when possible – correction of the problem, back to the normally anechoic IVC we usually see.
ps note there is also a mirror artifact in the right lower portion of the field, making it look as though there are two beating hearts.