POCUS in Shock
immediate assessment
Point-of-care ultrasound (POCUS) in shock: a focused, qualitative bedside scan of heart, IVC and lungs to categorize the shock and guide immediate management; not a diagnostic echocardiogram (1).
Use it when hypotension or shock is undifferentiated, or to confirm a working diagnosis before committing to fluids, pressors, or a procedure.
First pass, under 2 minutes: pump (cardiac, subcostal or parasternal), tank (inferior vena cava, IVC), lungs (bilateral anterior fields). Correlate every finding with vitals and exam; never interpret in isolation.
do not let scanning delay care
- Do not delay fluid resuscitation, antibiotics, or vasopressors to obtain images.
- Alarming first-pass finding (pericardial effusion with RV collapse, dilated RV with septal flattening): treat the working diagnosis and escalate while you gather more views; do not wait for a complete study.
define & classify
Map findings to pump, tank, pipes (RUSH) (2) or fluid, form, function, filling (SHoC) (3): the goal is a shock pattern, not a formal diagnosis. Left ventricle (LV) and right ventricle (RV) size anchor the cardiac pattern; right atrium (RA) collapse marks tamponade physiology.
| pattern | cardiac (pump) | IVC / lung (tank) |
|---|---|---|
| Hypovolemic | Hyperdynamic, small LV cavity, walls nearly touching in systole (kissing walls) | IVC thin and collapsing, clear lungs |
| Cardiogenic | Dilated LV, poor global contractility | IVC often plethoric, B-lines (pulmonary edema) |
| Obstructive, pulmonary embolism (PE) | Dilated RV, RV ≥ LV, septal flattening (D-sign) | IVC plethoric, lungs usually clear |
| Obstructive, tamponade | Pericardial effusion, RV diastolic collapse, RA systolic collapse | IVC plethoric, minimal respiratory variation |
| Distributive (septic) | Hyperdynamic LV, chambers normal or small, no effusion | IVC variable, no B-lines |
Pipes (aorta, DVT) complete RUSH but are outside this page; scan them when ruptured aneurysm or massive PE is on the differential.
initial management
This section is the scan itself, performed in sequence so nothing is missed.
probe positions
- 1, parasternal: left sternal border, 3rd to 4th intercostal space.
- 2, apical: left 5th intercostal space, anterior axillary line, over the heart apex.
- 3, subxiphoid / subcostal: just below the xiphoid, probe flat on the abdomen and angled cephalad for the cardiac view; rotate roughly 90° toward the right shoulder for the IVC long axis.
cardiac (pump)
- Parasternal or subcostal view (subcostal is the fallback when supine, ventilated, or poorly positioned), qualitative squeeze only, you are not calculating an ejection fraction.
- Compare RV size to LV size in the same view, RV approaching or exceeding LV size is abnormal.
- Scan for a pericardial effusion and note any chamber collapse.
IVC (tank)
- Subcostal long axis, roughly 2 cm distal to the RA-IVC junction: plethoric and non-collapsing (diameter > 2.1 cm, collapse < 50%) suggests high right-sided filling pressure (4), thin and fully collapsing suggests the opposite. One data point only, see pitfalls below.
lungs
- Bilateral anterior chest points, confirm lung sliding first (rules against pneumothorax there). Diffuse B-lines favor a cardiogenic or fluid-overload component, clear fields with a hyperdynamic heart favor distributive or hypovolemic (5).
reassess
- Re-scan IVC and lung fields after each 500 mL crystalloid bolus, within 5 to 10 minutes of it running in.
- New or worsening bilateral B-lines during fluid resuscitation = stop signal (FALLS-protocol logic) (5): endpoint for further fluid; reassess the shock category.
- Re-image the heart after starting or titrating a vasopressor or inotrope: contractility and RV size change quickly. See vasopressors and inotropes.
advanced management
fluid responsiveness
serial CCUS to guide therapy
- SCCM 2024 focused update: serial critical care ultrasonography (CCUS), not a single snapshot, to guide septic shock, cardiogenic shock and volume management (7); trend the same views over hours as pressors and fluid balance change.
when the picture stays unclear
- Discordant findings, a limited study, or persistent shock despite a “reassuring” scan: request a formal comprehensive echocardiogram; do not keep re-scanning.
troubleshooting
can’t get an adequate window
- Reposition (left lateral decubitus helps parasternal/apical views), try an adjacent space, or adjust depth and gain before assuming there is no window.
- Switch to the subcostal window if dressings, lines, or body habitus block the parasternal approach.
- If still non-diagnostic, say so. Do not force an interpretation, escalate for a formal study instead.
pattern to action
- RV ≥ LV with septal flattening (D-sign) → suspect massive/submassive PE → escalate, work up per the PE pathway, involve ICU/cardiology early.
- Pericardial effusion with RV diastolic and RA systolic collapse, plethoric IVC (8) → tamponade physiology → emergent pericardiocentesis; do not wait for a formal echo.
- Small hyperdynamic LV, kissing walls, collapsing thin IVC → hypovolemia → fluid bolus, reassess.
- Dilated LV, poor contractility, plethoric IVC, B-lines → cardiogenic component → fluid cautiously if at all, consider inotrope, see cardiogenic shock.
- Hyperdynamic LV, no effusion, no B-lines, clinical picture fits infection → distributive (septic) most likely → treat per the sepsis pathway, see shock.
escalation / ICU
call ICU / cardiology urgently for
- Tamponade physiology on bedside echo, this needs emergent pericardiocentesis.
- New RV dilation with septal flattening in a hemodynamically unstable patient, concerning for massive or submassive PE.
- Poor LV contractility with ongoing hemodynamic compromise despite initial measures, for inotrope titration or mechanical support evaluation.
- Any finding you are not confident interpreting in a patient who is unstable, ask before you act on it.
- Discordant POCUS findings and clinical trajectory, get a formal echocardiogram urgently rather than re-scanning repeatedly yourself.
pearls & pitfalls
- Focused bedside tool for a trained user, not a substitute for comprehensive echocardiography: order one whenever diagnosis or management hinges on the finding, or you are not confident in what you see.
- A normal RV does not exclude PE: sensitivity for right heart strain falls with smaller or peripheral clots. High clinical suspicion: pursue the PE workup regardless.
- A preserved-looking LV squeeze does not exclude cardiogenic shock: right heart failure, severe valvular disease, arrhythmia and diastolic dysfunction can all drive it with a normal-looking LV.
- A single IVC measurement weakly predicts fluid responsiveness, especially when spontaneously breathing or on low-tidal-volume / assisted ventilation; confounded by right heart dysfunction, intra-abdominal hypertension and technique. One data point, not a test.
- A technically difficult study (obesity, dressings, bowel gas, ventilator) can look falsely reassuring or alarming: low threshold to call it non-diagnostic.
sources
dosing above follows international guidance. Verify against the current Kuwait / MOH or hospital protocol where locally sensitive.
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Last updated · September 2026