You should see a nice vertically-aligned segment of the portal vein pop into view; easily recognized by its bright hyperechoic borders and hepatopetal blood flow (which will look RED on colour doppler).

10/
Finally, we can look at other associated pathology.

In HF, we will often see other features such as bilateral simple pleural effusions; plus supportive cardiac findings.

In inflammatory/infectious causes, you may see unilateral consolidations, dynamic air bronchograms, shred signs, etc.

9/
B lines arising from pulmonary edema should be bilateral, symmetrical, and in a dependent gradient (ie. most prominent at the bases).

B lines from infectious/inflammatory pathologies, on the other hand, are often asymmetrical, non-gravitational, and may display skipped or spared areas.

7/
In contrast, with infectious/inflammatory pathologies, you will see B lines which are NOT homogenous throughout the interspace.

You may see all the B lines arising from a single point on the pleura; or even A lines throughout part of the interspace.

6/
Next, we can look at the distribution of B lines across the interspace.

Pleural fluid fills interlobular septae in a predictable and regular way; which generates B lines that are evenly spaced throughout the whole interspace.

5/
In contrast, B lines arising from an irregular, ragged, interrupted pleural line are more likely to be from infectious/inflammatory pathologies.

(If you want to know WHY this happens - check out the video above!👆)

4/
And there are several ultrasound features that we can use to tease apart these two types.

First: we can look at the pleural morphology.

B lines arising from a smooth, crisp, uniform pleural line are more likely to be from cardiogenic pulmonary edema.

9/
The transhepatic view - sometimes called the rescue view - is another great option for difficult cases ⛑️

This is found in the mid-axillary line in a coronal plane (for the long-axis). From your standard view of the kidney, fan or slide your probe anteriorly until the IVC pops into view.

8/
Next: don't forget your troubleshooting arsenal 🏹

The IVC can be tough, so it's worth having a couple tricks up your sleeve for challenging cases 🃏

For example - the phased array probe (vs the curvilinear) often nestles better into the subxiphoid space, giving you a better view.

6/
We also want to be wary of overcalling "IVC collapse" in the long-axis, especially if we're losing the clearly defined borders of the vessel with inspiration 📏

You may be seeing lateral translation of the IVC with respiration - it's moving out of your plane of view - rather than true collapse

5/
Thirdly: avoid assessing the IVC right at the diaphragm ❌

The diaphragm can either stent the IVC open or "pinch it" during respiration, which is not the same as true collapse.

Train your eye (ideally) a couple cm distal to the hepatic vein

4/
Next: beware the pitfalls of a single view!

This is an axiom that holds true for all of POCUS - always look in more than one view 👍

With the IVC, the short-axis provides a plethora of useful information; including shape/sphericity, which is arguably the most useful parameter of all