POCUS & CCE

Protocol Overview

Indications: hypotension/shock, respiratory failure. Phased array probe, cardiac mode. Left lateral decubitus when feasible.

7 required views PLAX ×2 · PSAX ×1 · A4C ×1 · SC4C ×1 · IVC ×2

PLAX — Parasternal Long Axis ▼

View 1 — PLAX "Deep" Shot (depth ≥18 cm)

Purpose: Evaluate for left pleural effusion posterior to the descending thoracic aorta
Increase depth to ≥18 cm to visualize far field beyond the heart
Critical distinction: Pleural effusion = anechoic collection posterior to descending aorta; pericardial effusion tracks anterior to descending aorta

Do not miss a left pleural effusion by using shallow depth only

View 2 — PLAX "Shallow" Shot (depth just beyond thoracic aorta)

Probe: Left sternal border, 3rd–4th ICS, marker → right shoulder
2D: RV (anterior), IVS, LV cavity, MV leaflets, LVOT, AV, aortic root, LA, descending aorta (posterior)
Assess: LV size and systolic function (visual EF), RV size, MV and AV leaflet motion, pericardial effusion

PSAX — Parasternal Short Axis ▼

View 3 — PSAX at Papillary Muscle Level

From PLAX: rotate 90° clockwise, marker → left shoulder
2D: circular LV with anterolateral and posteromedial papillary muscles
Assess: RWMA (all coronary territories represented at this level), LV systolic function (fractional area change)
D-sign / septal flattening: flattening in diastole → RV volume overload; in systole → RV pressure overload
Fan superiorly → AV level (morphology, RVOT); fan inferiorly → apex (apical wall motion)

Best single view for RV pressure vs volume overload All coronary territories visible at papillary muscle level

Apical ▼

View 4 — Apical 4-Chamber (A4C)

Probe: cardiac apex (5th ICS, midaxillary line or PMI), marker → 4–5 o'clock; left lateral decubitus ideal
2D: LV (left of screen), RV (right), LA, RA, MV, TV, IAS, IVS
Ensure LV is not foreshortened — apex should taper to an ellipsoid, not appear rounded
Assess: LV systolic function (visual EF), RV:LV ratio (>0.6 = dilated; >1.0 = severely dilated), RWMA, pericardial effusion

Subcostal ▼

View 5 — Subcostal 4-Chamber (SC4C)

Probe: subxiphoid, nearly flat; marker → patient's left (3 o'clock); patient supine, knees bent
Liver as acoustic window; RV nearest transducer
Best view for pericardial effusion — fluid between myocardium and pericardium, distinct from liver and pleural fluid
Assess: global biventricular function, interatrial septum
Backup when parasternal/apical windows poor (COPD, MV, surgical dressings, post-sternotomy)

View 6 — IVC Long Axis

From SC4C: rotate 90° CCW, marker → patient's head (12 o'clock), angle slightly rightward
Landmark: hepatic vein confluence entering IVC near RA
Measure IVC diameter ~2 cm from RA junction
Assess collapsibility (spontaneous breathing) or distensibility (mechanically ventilated)
⚠ Multiple confounders limit interpretation — see Reference tab for full caveat list

Interpret with caution post-bypass and in right heart failure

View 7 — IVC Short Axis

From IVC long axis: rotate 90° — IVC in cross-section as it enters RA
Confirms IVC vs aorta; assess for thrombus in IVC lumen

Interpretation Summary ▼

Post-Cardiac Surgery Considerations

Pericardial effusion post-cardiac surgery often loculated — subcostal alone may miss posterior/lateral collections
Mediastinal air and drains might limit POCUS views

Protocol Overview

6 required zones, bilateral. Label clips with zone code. Probe: linear (superficial) or curvilinear (effusion, deeper structures).

6 required views (L1, L2, L3, R1, R2, R3) Linear probe — sliding, A/B-lines Curvilinear — effusion, consolidation

Left Hemithorax ▼

L1 — Left Anterior Lung Zone ▼

L1 — Left Anterior Lung Zone

Probe: mid-clavicular line, 1st–3rd ICS
Assess: lung sliding (present/absent), A-lines, B-lines

L2 — Left Lateral Lung Zone ▼

L2 — Left Lateral Lung Zone

Probe: anterior axillary line, 3rd–5th ICS
Assess: lung sliding, A-lines, B-lines

L3 — Left Posterolateral Lung Zone ▼

L3 — Left Posterolateral Lung Zone

Probe: mid-to-posterior axillary line, 5th–7th ICS
Assess: pleural effusion, consolidation, atelectasis
>90% sensitivity for pleural effusion at posterolateral zone

Right Hemithorax ▼

R1 — Right Anterior Lung Zone ▼

R1 — Right Anterior Lung Zone

Probe: mid-clavicular line, 1st–3rd ICS
Assess: lung sliding, A-lines, B-lines (same as L1)

R2 — Right Lateral Lung Zone ▼

R2 — Right Lateral Lung Zone

Probe: anterior axillary line, 3rd–5th ICS
Assess: same as R1

R3 — Right Posterolateral Lung Zone ▼

R3 — Right Posterolateral Lung Zone

Probe: mid-to-posterior axillary line, 5th–7th ICS
Assess: pleural effusion, consolidation, atelectasis (same as L3)

Pattern Recognition ▼

Pattern Recognition

Lung sliding present + A-lines → normal aeration (or COPD/asthma with air trapping)
B-lines (≥3 per field, bilateral) → interstitial syndrome (pulmonary edema, ARDS, interstitial pneumonia)
Absent lung sliding + A-lines + lung point → pneumothorax (lung point is pathognomonic)
Consolidation → tissue-like pattern ± air bronchograms; dynamic air bronchograms = pneumonia; static = atelectasis
Pleural effusion → anechoic dependent collection; assess for septations (complex/exudative effusion)
Seashore sign (M-mode) → normal sliding; barcode/stratosphere sign → no sliding → pneumothorax

Protocol Overview

Indications: shock, respiratory failure, trauma. Curvilinear probe. Lung views (eFAST extension) use linear or curvilinear probe.

5 required views Label "RUQ" vs "LUQ" — spleen and liver can look similar

FAST & Renal-GU (5 Required Views) ▼

View 1 — Right Upper Quadrant (RUQ) / Morrison's Pouch ▼

View 1 — Right Upper Quadrant (RUQ) / Morrison's Pouch

Probe: right flank, coronal plane (marker cephalad), probe between rib interspaces
Visualize: hepatorenal recess (Morrison's pouch), right diaphragm, right pleural space
Fan through: assess for free fluid between liver and kidney, hemothorax above diaphragm
Free fluid: anechoic collection in hepatorenal space; even a thin sliver = significant volume
Label: "RUQ"

Most sensitive abdominal region — free fluid detected here first in supine patients

Views 2 & 3 — Left Upper Quadrant (LUQ) / Splenorenal ×2 ▼

Views 2 & 3 — Left Upper Quadrant (LUQ) / Splenorenal ×2

Probe: left posterior flank, more posterior than RUQ; probe between rib interspaces, marker cephalad
Visualize: splenorenal recess, left diaphragm, left pleural space
Fan through: free fluid between spleen and kidney, left hemothorax
Splenodiaphragmatic space (between spleen and diaphragm) is more sensitive for detecting free fluid than the splenorenal space — fan superiorly to assess
Obtain 2 clips (standard protocol) to ensure adequate coverage
Label: "LUQ"

Left side is harder — probe must be more posterior and superior than RUQ

Views 4 & 5 — Pelvis / Bladder ×2 ▼

Views 4 & 5 — Pelvis / Bladder ×2

Probe: suprapubic, marker toward patient's right for transverse view; rotate 90° for sagittal
Bladder as acoustic window (fill with fluid if empty for better visualization)
Transverse: assess for free fluid lateral to bladder, in pouch of Douglas (females) or rectovesical pouch (males)
Sagittal: posterior to bladder in dependent pelvis
Obtain both transverse and sagittal clips

eFAST Extension — Bilateral Anterior Lung Views ▼

eFAST Extension — Bilateral Anterior Lung Views

Anterior chest, 2nd ICS midclavicular line bilaterally
Pneumothorax: absent lung sliding + absent B-lines + A-lines present → lung point confirms
Hemothorax: anechoic collection above diaphragm in RUQ/LUQ views (fan superiorly)

Key Findings ▼

Key Findings

Positive FAST + hemodynamic instability → OR Sensitivity 69–98%; negative does not exclude injury; serial exams increase yield

Protocol Overview

Linear high-frequency probe. 5 required compression sites per leg, 1 optional. Compress in transverse plane — normal vein collapses completely; thrombosed vein does not. Record each site with and without compression.

10 required views (5 per leg) +2 optional (adductor canal ×2) Label laterality at minimum ("LEFT" / "RIGHT")

Femoral Region (bilateral) ▼

Point 1 — Common Femoral Vein (CFV) ▼

Point 1 — Common Femoral Vein (CFV)

Probe transverse at inguinal ligament
Identify CFV (medial) and CFA (lateral)
Compress: complete collapse = normal; non-compressible = DVT

Label: L CFV / R CFV

Point 2 — CFV at Greater Saphenous Vein (GSV) Junction ▼

Point 2 — CFV at Greater Saphenous Vein (GSV) Junction

Slide probe slightly distally to saphenofemoral junction
Identify GSV entering CFV — "Mickey Mouse sign": CFV, CFA, and GSV visible in transverse
Compress at this level

Label: L GSV / R GSV

Point 3 — CFV at Lateral Perforator Vein ▼

Point 3 — CFV at Lateral Perforator Vein

Continue distally; identify lateral perforator vein entering CFV
Can be difficult to visualize but usually obtainable
Compress at this level

Label: L perf / R perf

Point 4 — Femoral Vein (FV) — Mid-Thigh ▼

Point 4 — Femoral Vein (FV) — Mid-Thigh

Continue distally into mid-thigh; FV runs deep to sartorius muscle alongside the SFA
Previously called "superficial femoral vein" — misnomer, it is a deep vein
This is the segment missed by 2-point protocols; SRU recommends compression here to avoid false negatives
Compress at this level

Label: L FV / R FV Most commonly missed segment in 2-point protocols

Popliteal Region (bilateral) ▼

Point 5 — Popliteal Vein ▼

Point 5 — Popliteal Vein

Patient: knee slightly flexed (pillow under knee or frog-leg position)
Probe transverse in popliteal fossa
Identify popliteal vein (superficial) and popliteal artery (deep, pulsatile)
Compress; fan through to trifurcation of calf veins

Label: L pop / R pop

Optional ▼

Point 6 — Adductor Canal (Optional) ▼

Point 6 — Adductor Canal (Optional)

Probe transverse at distal medial thigh
FV within adductor canal (between sartorius and adductor muscles)
Compress at this level
Perform when clinical suspicion is high despite negative proximal exam

Calf vein assessment: defer to formal duplex in vascular lab

Technique & Interpretation ▼

Technique & Interpretation

Normal: vein fully compressible with direct transducer pressure in transverse plane
DVT: non-compressible lumen — partial or complete; echogenic thrombus may be visible
Augmentation (Doppler): squeeze distal calf — increased venous flow; absence suggests proximal obstruction
Negative exam but ongoing suspicion: complete duplex Doppler (vascular lab) within 5–7 days

High relevance post-cardiac surgery — HIT, femoral cannulation sites, prolonged immobility

Protocol Overview

Indication: aspiration risk assessment. Low-frequency curvilinear probe. Sagittal epigastric plane. Landmark: gastric antrum between left lobe of liver (anterior) and pancreas/aorta (posterior).

2 required views — supine + RLD Curvilinear probe, 2–5 MHz

Views ▼

View 1 — Supine Sagittal ▼

View 1 — Supine Sagittal

Probe sagittal at epigastrium; liver (anterior) and aorta/pancreas (posterior) as landmarks
Identify gastric antrum in cross-section
Assess qualitatively: empty, fluid, or solid content
Fluid appears anechoic/hypoechoic; solid content is heterogeneous, hyperechoic ("frosted glass")

View 2 — Right Lateral Decubitus (RLD) Sagittal ▼

View 2 — Right Lateral Decubitus (RLD) Sagittal

Roll patient to right side and repeat sagittal epigastric view
Most sensitive position — gastric contents pool in dependent antrum
Measure antral cross-sectional area (CSA) at the level of the aorta
CSA = π × (AP × CC) / 4 (ellipse formula; AP and CC diameters measured in cm)

RLD is the primary quantitative view — always obtain this position

Interpretation ▼

3-Point Grading System ▼

3-Point Grading System

Grade 0 (empty): No fluid in either position → low aspiration risk
Grade 1: Fluid visible in RLD only → consistent with baseline secretions, low risk
Grade 2: Distended antrum with fluid in both supine and RLD → gastric volume >100 mL, higher aspiration risk

Solid content (heterogeneous, hyperechoic "frosted glass") → high risk regardless of grade or volume.

Quantitative Volume — Perlas Formula ▼

Quantitative Volume — Perlas Formula

Gastric volume (mL) = 27.0 + 14.6 × RLD CSA − 1.28 × age
Volume >1.5 mL/kg → full stomach (high aspiration risk)
Volume >100 mL → correlates with Grade 2; consider RSI or case deferral
Coronal view (optional): may improve detection of gastric distension

>1.5 mL/kg = full stomach threshold Source: ASRA gastric POCUS recommendations (Haskins 2021, 2025)

Minimum Exam Requirements (every CCE)

Visualize LV and RV in a minimum of 2 views per chamber
Quantify at least one of: LV stroke volume, RVSP, or diastolic function grade
Visualize mitral, tricuspid, and aortic valves with both 2D and color Doppler

If a view cannot be obtained, document the attempt. Workflow at each window: 2D → Color Doppler → Spectral Doppler.

★ = overlaps with basic FoCUS *** = optional / clinically indicated only

Parasternal Long Axis PLAX ★ Basic ▼

Parasternal Long Axis — RV Inflow PLAX-RVI *** Optional ▼

Parasternal Short Axis PSAX ★ Basic (papillary level) ▼

Apical 4-Chamber A4C ★ Basic ▼

Apical 5-Chamber A5C ▼

Apical 2-Chamber A2C ▼

Apical 3-Chamber (Apical Long Axis) A3C / APLAX *** Optional ▼

Subcostal 4-Chamber SC4C ★ Basic ▼

Subcostal IVC SC-IVC ★ Basic ▼

Key Hemodynamic Parameters — Quick Reference ▼

Parameter	Window / Method	Normal / Threshold
LVOT VTI	A5C — PW Doppler	18–22 cm; stroke distance for trending
Stroke Volume	A5C — LVOT VTI × LVOT area	60–100 mL
E/e′ (average)	A4C — TDI at MV annulus	<14 normal; ≥14 → elevated filling pressures
TAPSE	A4C — M-mode at TV annulus	≥17 mm (normal RV longitudinal function)
RV s′	A4C — TDI at TV annulus	≥10 cm/s (normal RV systolic function)
RVSP	A4C — CW through TR jet	4(TR V_max)² + RAP; >35 mmHg elevated
IVC diameter	SC-IVC — 2 cm from RA	≤2.1 cm + >50% collapse → RAP ~0–5 mmHg; ⚠ multiple confounders — see Reference tab
EPSS	PLAX — M-mode at MV tips	≤7 mm normal; >7 mm → reduced EF
MAPSE	A4C — M-mode at MV annulus	≥10 mm (normal LV longitudinal function)
PAAT	PSAX (AV level) — PW at PV	>100 ms normal; <60 ms → severe PH
Dimensionless index	A5C — LVOT VTI / AV VTI	>0.50 normal; <0.25 → severe AS

Cardiac ▼

Pericardial Effusion / Cardiac Tamponade ▼

1
Anechoic space between epicardium and pericardium — circumferential in large effusions. Key distinction: pericardial fluid tracks anterior to descending aorta on PLAX; pleural fluid tracks posterior
2
RV diastolic collapse — most specific echocardiographic sign of tamponade; best seen in PLAX or subcostal views
3
RA systolic inversion — RA wall inverts inward during ventricular systole; duration >1/3 of cardiac cycle is both sensitive and highly specific
4
Respiratory variation in MV/TV inflow — trans-mitral variation >25–30%, trans-tricuspid >40–60% on PW Doppler; echocardiographic pulsus paradoxus
5
Plethoric IVC — diameter >2.1 cm with <50% inspiratory collapse; reflects elevated RAP from impaired venous return

⚠ Post-cardiac surgery: Effusions occur in ~18% post-op and are frequently loculated hematomas. A loculated hematoma can cause regional tamponade compressing only selected chambers (often left-sided) — classic RV collapse, RA inversion, and Doppler variation are often absent. TTE may be inadequate — TEE is often required for posterior or left-sided hematomas not visible on standard windows. Always compare with pre-op and intraoperative imaging. Distinguish pre-existing epicardial fat pad (echogenic, anterior, non-dependent, present on prior studies) from new hematoma (heterogeneous, may be posterior or lateral, new since prior imaging).

RV Failure ▼

1
RV dilation — RV:LV ratio >1.0 in A4C (RV-focused view); RV basal diameter >4.1 cm indicates dilation
2
Reduced TAPSE — M-mode at lateral TV annulus in A4C; <17 mm indicates RV longitudinal systolic dysfunction
3
Interventricular septal flattening (D-sign) — diastolic flattening = RV volume overload; systolic flattening = RV pressure overload; eccentricity index >1.0 = RV overload at PSAX papillary level
4
Reduced RV S' velocity — TDI at lateral TV annulus; <10 cm/s indicates RV systolic dysfunction
5
Reduced RVFAC — fractional area change <35% in A4C; trace RV endocardium in diastole and systole

TAPSE:PASP ratio <0.32 mm/mmHg = RV-PA uncoupling McConnell's sign → free wall akinesis + apical sparing = acute PE until proven otherwise

LV Failure / Low EF ▼

1
Visual EF estimation — qualitative "eyeball" in PLAX, PSAX, A4C, A2C; experienced operators achieve κ >0.9 vs formal biplane Simpson's; classify as <30%, 30–50%, >50%
2
EPSS >7 mm — E-point septal separation on PLAX M-mode at MV tips; >7 mm sensitive for LVEF ≤30%; >12–17 mm = moderate-to-severe dysfunction
3
MAPSE <10 mm — mitral annular plane systolic excursion; M-mode at lateral MV annulus in A4C; reflects reduced LV longitudinal function
4
Regional wall motion abnormalities (RWMA) — akinesis, hypokinesis, or dyskinesis; PSAX papillary level covers all coronary territories; suggests ischemic etiology
5
LV dilation — LVEDD >5.6 cm on PLAX, or visually enlarged LV cavity; often accompanies chronic systolic dysfunction

Hypovolemia / Fluid Responsiveness ▼

1
Small, hyperdynamic IVC — diameter <2.1 cm with >50% inspiratory collapse in spontaneously breathing patients; suggests low RAP and potential volume responsiveness
2
IVC collapsibility index (cIVC) — spontaneous breathing: cIVC ≥48% predicts FR with 84% sensitivity, 90% specificity; MV: dIVC >15% separates responders from non-responders
3
Small, hyperdynamic LV ("kissing walls") — near-obliteration of LV cavity in systole on PSAX or A4C; small LVEDA; suggests severe hypovolemia and reduced preload
4
LVOT VTI variation with passive leg raise (PLR) — >10–12% increase in LVOT VTI after PLR predicts fluid responsiveness; applicable in spontaneous breathing, MV, and arrhythmias
5
Flat, collapsed IVC — IVC diameter <9 mm at multiple levels suggests significant hypovolemia; highly predictive when combined with hyperdynamic LV

⚠ Critical caveat: IVC reflects right-sided filling pressures, not LV preload or fluid responsiveness directly. RV dysfunction, elevated IAP, MV settings, and patient effort all confound IVC dynamics. PLR + LVOT VTI change is the most robust dynamic predictor. See Reference tab for full IVC caveat list.

Venous Congestion — VExUS ▼

1
Plethoric IVC (>2.0 cm) — gating criterion; if non-plethoric, VExUS grade = 0 regardless of other findings
2
Hepatic vein Doppler — normal: biphasic S > D; mild: S = D; severe: systolic flow reversal (S wave reversed)
3
Portal vein pulsatility — normal: continuous low-pulsatility; mild: pulsatility index >30%; severe: pulsatility >50% with intermittent flow reversal
4
Intrarenal venous Doppler — normal: continuous flow; mild: discontinuous biphasic (S and D); severe: monophasic diastolic-only flow
5
VExUS grading — Grade 0: IVC <2 cm; Grade 1: plethoric + no severe; Grade 2: plethoric + 1 severe; Grade 3: plethoric + ≥2 severe → highest congestion, associated with AKI and adverse outcomes

Integrates IVC + hepatic + portal + renal vein Doppler Curvilinear probe for all VExUS views

Aortic Stenosis (POCUS Screening) ▼

1
Calcified / thickened AV with restricted opening — PLAX and PSAX (AV level); heavily calcified, immobile leaflets are the hallmark 2D finding
2
Elevated peak aortic jet velocity (V_max) — CW Doppler from A5C or A3C; V_max ≥4 m/s = severe; 3–4 m/s = moderate (2020 ACC/AHA VHD guidelines)
3
Elevated mean transvalvular gradient — from CW Doppler envelope; ≥40 mmHg = severe AS
4
Reduced AVA by continuity equation — LVOT VTI × LVOT area / AV VTI; AVA ≤1.0 cm² = severe; AVAi ≤0.6 cm²/m² = severe indexed
5
Concentric LV hypertrophy — increased wall thickness, normal/small cavity; secondary sign of chronic pressure overload

⚠ POCUS caveat: Sensitivity ~83%, specificity ~100% for significant AS by experienced operators. CW Doppler alignment critical — misalignment underestimates gradients. Low-flow, low-gradient AS requires dobutamine stress echo or CT-AVC — not diagnosable by POCUS.

Pulmonary ▼

Pneumothorax ▼

1
Absent lung sliding — most sensitive sign; visceral pleura no longer glides against parietal pleura; also absent in pleurodesis, mainstem intubation, apnea, severe consolidation
2
Absent B-lines — a single B-line at any intercostal space rules out pneumothorax at that location; B-lines require pleural apposition
3
Lung point — transition where sliding appears and disappears with respiration; 100% specific for pneumothorax; marks its border
4
Barcode / stratosphere sign (M-mode) — parallel horizontal lines replacing the normal seashore sign; confirms absent lung sliding
5
Absent lung pulse — in apnea, cardiac pulsations transmitted to pleura ("lung pulse") normally visible; absence suggests PTX rather than other causes of absent sliding

Sensitivity 89%, specificity 99% — far exceeds supine CXR (30–75%) Start at 2nd ICS MCL anteriorly; look for lung point laterally

Pleural Effusion ▼

1
Anechoic space above diaphragm — gravity-dependent collection between pleural layers; best in posterolateral zones (L3/R3) with patient upright or semi-recumbent
2
Quad sign — effusion bounded by pleural line (superior), lung line (inferior), and rib shadows (lateral) forming a quadrilateral
3
Sinusoid sign (M-mode) — lung line moves toward pleural line with inspiration; distinguishes effusion from consolidation
4
Spine sign — vertebral bodies visible above the diaphragm through the effusion (normally blocked by air-filled lung)
5
Fluid characterization — simple (anechoic) vs. complex (echogenic, septated, floating debris); complex = exudate, empyema, or hemothorax

>90% sensitivity — far exceeds supine CXR Post-CPB: left effusions common — always check L3 on post-op exam

Pulmonary Embolism (Indirect Signs) ▼

1
RV dilation (RV:LV >1.0) — A4C view; most commonly used echocardiographic marker of PE-related RV strain (2026 AHA/ACC PE Guideline)
2
McConnell's sign — akinesia of RV mid-free wall with preserved (hypercontractile) apical motion; distinctive for acute PE
3
60/60 sign — RVOT acceleration time <60 ms + notching of RVOT Doppler envelope + TR gradient <60 mmHg; consistent with acute RV pressure overload from PE
4
Reduced TAPSE — reflects acute RV systolic impairment; guides risk stratification per 2026 AHA/ACC PE guideline
5
Paradoxical septal motion + plethoric IVC — leftward septal bowing in systole + non-collapsing IVC; combination strongly suggests hemodynamically significant PE

Thrombus-in-transit (RA/RV/PA): rare, pathognomonic, emergent BLUE protocol for PE: A-line profile + positive DVT compression US

Interstitial Lung Syndrome (B-line Pattern) ▼

1
≥3 B-lines per intercostal space — vertical hyperechoic artifacts from pleural line to screen bottom, moving with sliding; ≥3 in a single field = "positive" zone
2
Bilateral diffuse B-lines (B-profile) + preserved sliding — symmetric anterior/lateral distribution = acute cardiogenic pulmonary edema (most common cause)
3
B-lines + reduced/absent sliding (B'-profile) — suggests non-cardiogenic disease: ARDS, viral pneumonitis, interstitial lung fibrosis
4
Irregular / thickened pleural line — fragmented pleural line, subpleural irregularities = pneumonia, ARDS, or ILD rather than cardiogenic edema
5
Quantification and distribution — total B-line count correlates with extravascular lung water; focal/asymmetric = pneumonia or contusion; monitor response to diuresis serially

Non-Cardiac / Abdominal ▼

Abdominal Free Fluid (FAST) ▼

1
Anechoic stripe in Morrison's pouch — hepatorenal recess; most sensitive location for free fluid in the supine patient
2
Fluid in splenorenal recess or perisplenic space — LUQ view; probe must be more posterior and superior than RUQ
3
Pelvic free fluid — rectovesical pouch (males) or pouch of Douglas (females); transverse and sagittal suprapubic views
4
Subdiaphragmatic fluid — fluid above liver or spleen, below diaphragm; fan superiorly from RUQ/LUQ views
5
Serial exams increase sensitivity — sensitivity 69–98% for hemoperitoneum; serial exams improve yield to 72–93%

Positive + hemodynamic instability → OR Negative does not exclude injury

Deep Vein Thrombosis (DVT) ▼

1
Non-compressible vein — hallmark finding; normal vein collapses completely with transducer pressure in transverse plane; thrombosed vein does not
2
Echogenic intraluminal material — visible thrombus; acute thrombus may be anechoic and detectable only by non-compressibility
3
Distended vein — acutely thrombosed veins are often larger than the adjacent artery
4
Absent or diminished color flow — on color Doppler, flow absent or reduced in thrombosed segment
5
Absent augmentation — distal calf compression fails to augment proximal flow on spectral Doppler

Post-cardiac surgery: HIT, femoral cannulation, immobility — high pretest probability Duke protocol: 5+1 compression points per leg

Lung Consolidation / Pneumonia ▼

1
Tissue-like sign ("hepatization") — consolidated lung resembles liver parenchyma in echogenicity
2
Air bronchograms — hyperechoic linear/punctate structures within consolidation; dynamic (moving with respiration) = pneumonia; static = atelectasis
3
Shred sign — irregular, jagged border between consolidated and aerated lung
4
Fluid bronchograms — anechoic fluid-filled bronchi within consolidation; suggests obstructive atelectasis
5
Associated pleural effusion — parapneumonic effusion common with bacterial consolidation; characterize for septations or empyema features

Protocol ▼

View Count Summary ▼

Exam	Required	Optional	Notes
Focused Cardiac	7	—	PLAX ×2, PSAX ×1, A4C ×1, SC4C ×1, IVC long ×1, IVC short ×1
Lung	6	—	L1, L2, L3, R1, R2, R3 — label every clip
FAST / Renal-GU	5	—	RUQ, LUQ ×2, Pelvis ×2 — label RUQ vs LUQ
LE Venous DVT	10	2	5 per leg (CFV, GSV, perf, FV, pop) + adductor canal optional
Gastric	2	1	Supine sagittal + RLD sagittal; coronal optional
Total	30	3

Probe Selection ▼

Probe	Frequency	Use For
Phased array	2–5 MHz	Cardiac (all views), subcostal IVC
Linear	5–12 MHz	Lung sliding / A-B lines, DVT compression, superficial structures
Curvilinear	2–5 MHz	FAST (abdomen/pelvis), lung effusion/consolidation, gastric, aorta

Clip Labeling Guide ▼

Cardiac: PLAX-deep, PLAX, PSAX, A4C, SC4C, IVC-long, IVC-short
Lung: L1, L2, L3, R1, R2, R3
FAST: RUQ, LUQ (label — spleen and liver look similar), Pelvis-transverse, Pelvis-sagittal
DVT (left leg): L CFV, L GSV, L perf, L FV, L pop — use R prefix for right leg
Gastric: Gastric-supine, Gastric-RLD

Cardiac ▼

CCE — Key Hemodynamic Parameters ▼

Parameter	Window / Method	Normal / Threshold
LVOT VTI	A5C — PW Doppler	18–22 cm; use for trending SV
Stroke Volume	LVOT VTI × π/4 × (LVOT diameter)²	60–100 mL
E/e′ (average)	A4C — TDI lateral + medial MV annulus	<14 normal; ≥14 → elevated filling pressures
TAPSE	A4C — M-mode at TV annulus	≥17 mm
MAPSE	A4C — M-mode at MV annulus	≥10 mm
RV s′	A4C — TDI at TV annulus	≥10 cm/s
RVSP	A4C — CW through TR jet	4(TR V_max)² + RAP; >35 mmHg elevated
EPSS	PLAX — M-mode at MV tips	≤7 mm normal; >7 mm → reduced EF
PAAT	PSAX (AV level) — PW at PV	>100 ms normal; <60 ms → severe PH
Dimensionless index	A5C — LVOT VTI / AV VTI	>0.50 normal; <0.25 → severe AS
RV:LV ratio	A4C — area ratio	<0.6 normal; >1.0 severely dilated

LV Function — Quick Assessment ▼

Method	View	Finding
Visual EF	Any	<30% / 30–50% / >50% — bucket estimation
EPSS	PLAX M-mode	>7 mm → reduced EF
Fractional area change	PSAX papillary level	<35% → systolic dysfunction
MAPSE	A4C M-mode	<10 mm → reduced longitudinal function
Biplane Simpson's	A4C + A2C	Trace endocardium ED and ES

Pericardial vs Pleural Effusion ▼

PLAX deep shot (≥18 cm depth): fluid posterior to descending aorta = pleural; fluid anterior = pericardial
SC4C: best view for pericardial effusion — fluid between myocardium and pericardium, distinct from liver
Post-cardiac surgery: effusions often loculated — do not rely on subcostal alone; check multiple windows
Tamponade signs: RA diastolic collapse, RV diastolic collapse, IVC plethora (>2.1 cm, non-collapsing), respiratory variation in inflow velocities

D-Sign — RV Overload Interpretation ▼

Timing	Mechanism	Cause
Systolic flattening	RV pressure overload	PE, pulmonary hypertension, ARDS, hypoxic vasoconstriction
Diastolic flattening	RV volume overload	TR, ASD, RV infarct, post-CPB RV dilation
Both systole + diastole	Combined	Severe RV failure

IVC ▼

RAP Thresholds ▼

IVC Diameter	Collapsibility (cIVC)	Estimated RAP	Interpretation
≤2.1 cm	>50%	0–5 mmHg	Low RAP
≤2.1 cm	<50%	~8 mmHg	Intermediate — use clinical context
>2.1 cm	<50%	10–20 mmHg	Elevated RAP

Source: ASE/EACVI (Lang 2015). Moderate correlation with CVP only — interpret in context.

10 Conditions Where IVC POCUS May Fail ▼

IVC Is Not a Stand-Alone Measure

IVC diameter reflects a complex interplay of volaemia, right heart function, intrathoracic pressure, and intra-abdominal pressure simultaneously. Only extreme cIVC values (>40–50%) carry predictive value. Post-CPB: unreliable in first 6 hours (Sobczyk 2015, 2016). Always integrate with cardiac function and lung POCUS.

1. High PEEP / low tidal volume MV — low respiratory variation despite fluid responsiveness (false negative)
2. Assisted ventilation / NIV / CPAP — unpredictable interplay; IVC variation unreliable (FP and FN)
3. Variable spontaneous breathing — deep breaths exaggerate cIVC (FP); shallow breaths reduce sensitivity (FN)
4. Asthma / COPD exacerbation — auto-PEEP dilates IVC; forced expiration can mimic collapse (FP and FN)
5. Chronic RV dysfunction / severe TR — chronically dilated IVC; FR may coexist (FN)
6. RV myocardial infarction — dilated IVC + venous congestion may coexist with FR (FN)
7. Cardiac tamponade — IVC plethora expected; fluid challenge may still be beneficial (FN)
8. Intra-abdominal hypertension — compresses IVC regardless of volaemia; blunts variation (FP and FN)
9. Local mechanical factors — ECMO cannulae, cava filters, IVC thrombosis, extrinsic compression
10. Lateral IVC displacement — M-mode plane migrates off-axis; overestimates cIVC (FP) — use short-axis to confirm

All 10 are prevalent in the cardiac surgical ICU Via G et al. ICM 2016; Di Nicolò P et al. JCM 2023; Millington SJ. CJA 2019

Lung ▼

Pattern Recognition ▼

Pattern	Diagnosis
Sliding + A-lines	Normal aeration (or COPD/asthma)
Bilateral B-lines (≥3/field)	Interstitial syndrome — pulmonary edema, ARDS, ILD
Unilateral B-lines	Pneumonia, atelectasis, contusion
No sliding + A-lines	Pneumothorax — confirm with lung point
Lung point	Pathognomonic for pneumothorax
Consolidation ± air bronchograms	Pneumonia (dynamic) or atelectasis (static)
Anechoic dependent collection	Pleural effusion — assess for septations
M-mode seashore sign	Normal lung sliding
M-mode barcode/stratosphere sign	Absent sliding → pneumothorax

Gastric ▼

Aspiration Risk Quick Reference ▼

Grade	Finding	Risk
Grade 0	No fluid in either position	Low
Grade 1	Fluid in RLD only	Low — baseline secretions
Grade 2	Fluid in both supine + RLD	Higher — volume >100 mL; consider RSI
Solid content	Heterogeneous / "frosted glass"	High regardless of grade

Perlas formula: Volume (mL) = 27.0 + 14.6 × RLD CSA − 1.28 × age · CSA = π × (AP × CC) / 4 · >1.5 mL/kg = full stomach