RUSH — Undifferentiated ShockRUSH

Where to put the probe

Window

Heart (subxiphoid, PLAX, A4C), then IVC, lungs and FAST windows, then aorta and femoral veins

Marker

Per view — cardiac convention for the heart, HEAD for IVC, lungs and flanks, RIGHT for the aorta and vessels in transverse

probe

phased + linear

preset

cardiac / abdominal / vascular

depth

per view

Pump, tank, pipes

1. Pump: subxiphoid or PLAX first. Is there an effusion with collapse? Is the LV squeezing hard, normally or poorly? Is the RV bigger than the LV? Three answers in one view.
2. Tank: the IVC for size and collapse, then both lungs for B-lines, sliding and effusion, then the FAST flanks for free fluid. Fullness, leakiness and compromise of the tank.
3. Pipes: the abdominal aorta from diaphragm to bifurcation, then two-point compression of the common femoral and popliteal veins for DVT.
4. Put it together using the table below, then treat the most lethal reversible cause first and rescan after every intervention.

What you are looking at

Pump — the heart

Effusion and tamponade, global LV function, RV size. See the subcostal, PLAX, PSAX and A4C views.

Tank — the IVC

Small and collapsing means an empty tank; large and fixed means a full or obstructed one. See the IVC view.

Tank — the lungs

B-lines mean a leaking tank, absent sliding a tension pneumothorax, an effusion another place fluid has gone. See the lung views.

Tank — free fluid

FAST windows for blood or other fluid that has left the circulation. See the eFAST view.

Pipes — the aorta

An aneurysm in a hypotensive patient is a ruptured aneurysm. See the aorta view.

Pipes — the femoral veins

A non-compressible common femoral or popliteal vein supports PE as the obstructive cause.

Putting it together

Don’t be fooled — pitfalls

• Mixed shock is commonSeptic patients bleed, cardiac patients get septic. One abnormal finding does not close the differential; weigh the whole picture.
• The IVC is a filling-pressure gauge, not a fluid-responsiveness testA small IVC supports giving fluid; a large one does not prove the patient is full. Judge the response to a bolus by rescanning.
• Sepsis can look cardiogenicSeptic cardiomyopathy produces a poorly contracting LV; a hyperdynamic LV early on does not exclude sepsis either.
• Negative FAST, negative aorta, still bleedingRetroperitoneal, pelvic, thoracic and external bleeding escape the protocol. Hypovolemic physiology without a visible source is still hypovolemic.
• The order is a teaching orderIf the story screams tamponade, start there. The pump–tank–pipes sequence stops you forgetting steps; it does not override clinical priority.

Bad image? Fix it

• No cardiac windowTry all three cardiac windows before giving up; the subcostal view works in most supine, ventilated patients.
• Cannot assess the IVCUse the lungs and the heart instead: B-lines and a plethoric right heart tell you the tank is full without the IVC.
• Vein will not compressConfirm the probe is perpendicular and pressure is enough to dimple the artery; a real DVT stays round under pressure that deforms the artery.
• The exam is taking too longAnswer the single most lethal question first (tamponade, tension pneumothorax, ruptured aneurysm), act, then complete the rest.

So what — what the finding changes

• Empty tank, hyperdynamic pumpGive volume or blood and find the leak: aorta, FAST windows, chest, external, GI tract.
• Failing pump, full tankHold fluids; inotropes or vasopressors, treat the cause (ACS, arrhythmia, valve), and escalate to formal echo.
• Obstructive patternDrain the pericardium, decompress the chest, or treat the clot — each is a specific, time-critical intervention.
• Vigorous pump, normal tank, hypotensionDistributive physiology: cultures, antibiotics, vasopressors and source control while you keep rescanning.

Related views

Keep going