VEXUS Score: Components and Clinical Applications
Critical Clarification: VEXUS ≠ VTE Risk Assessment
The VEXUS (Venous Excess Ultrasound) score is NOT a venous thromboembolism risk assessment tool—it is a point-of-care ultrasound protocol for evaluating systemic venous congestion and fluid status. The question appears to conflate VEXUS with VTE risk scores (like Padua or IMPROVE), which are entirely different clinical tools.
VEXUS Score Components
The VEXUS score grades venous congestion from 0-3 by combining four ultrasound parameters 1, 2, 3:
1. Inferior Vena Cava (IVC) Assessment
- Severe dilation (>2 cm diameter) indicates volume overload 3
- IVC dilation strongly associates with elevated central venous pressure (P < .001) 3
2. Hepatic Vein Doppler (HVD)
- Normal: continuous forward flow
- Mild abnormality: phasic flow with S>D waves
- Severe abnormality: S-wave reversal 2, 4
- Severe HVD patterns associate with elevated CVP (P = .026) 3
3. Portal Vein Doppler (PVD)
- Normal: continuous flow with <30% pulsatility
- Mild abnormality: 30-50% pulsatility
- Severe abnormality: >50% pulsatility or flow reversal 2, 4
4. Intrarenal Venous Doppler (IRVD)
- Normal: continuous flow
- Mild abnormality: discontinuous monophasic flow
- Severe abnormality: biphasic flow 2, 3
- IRVD is the strongest independent predictor of elevated CVP among all VEXUS components (P = .005 for mild, P = .025 for severe patterns) 3
VEXUS Grading System
Score 0: No IVC dilation, all venous Doppler patterns normal 4
Score 1: Severe IVC dilation alone OR one abnormal venous Doppler pattern 2
Score 2: Severe IVC dilation + abnormalities in 1-2 venous territories 4
Score 3: Severe IVC dilation + abnormalities in all 3 venous territories (hepatic, portal, renal) 4
Clinical Applications
Acute Kidney Injury Management
- In ICU patients with severe AKI, VEXUS >1 should trigger diuretic therapy 2
- Patients who reduced their VEXUS score within 48 hours had significantly more renal replacement therapy-free days at 28 days (28.0 vs 15.0 days, P = .012) 2
- 75% of patients with VEXUS >1 received diuretics versus only 38.9% with VEXUS ≤1 (P = .001) 2
Acute Heart Failure
- VEXUS score 3 was the most prevalent pattern (39% of patients) in acute HF admissions 4
- VEXUS 3 independently predicts in-hospital mortality (OR 8.03,95% CI 2.25-28.61, P = .001) 4
- Adding VEXUS to the GWTG-HF mortality prediction model significantly improved performance (Δχ² = +8.44, P = .03) 4
- Patients with VEXUS 3 more commonly have chronic atrial fibrillation, chronic kidney disease, severe tricuspid regurgitation, and impaired right atrial function 4
Hemodialysis Fluid Management
- VEXUS can track dynamic changes in volume status during ultrafiltration 1
- However, only 15% of ESRD patients above dry weight had elevated VEXUS scores 1
- All patients with elevated VEXUS improved their scores with fluid removal 1
- Important caveat: Elevated VEXUS may reflect cardiac dysfunction (biventricular systolic impairment) rather than pure volume overload 1
Pediatric Critical Care
- VEXUS is 100% feasible in critically ill children and strongly associates with CVP levels (P < .001) 3
- IRVD assessment is the most reliable component in pediatric populations 3
Key Clinical Pitfalls
Cardiac vs. Volume Congestion: VEXUS may be elevated in biventricular heart failure independent of absolute volume status 1. Patients with elevated VEXUS commonly have both RV and LV systolic dysfunction 1.
Low Sensitivity in ESRD: Only 15% of volume-overloaded dialysis patients demonstrate elevated VEXUS 1, suggesting limited utility as a screening tool in this population.
Operator Dependence: Requires competency in obtaining hepatic, portal, and renal venous Doppler waveforms—not universally available skills 3.
Note: If you were asking about VTE risk stratification tools for exam preparation, the relevant scores are Padua (for medical patients) 5, IMPROVE (for VTE and bleeding risk) 5, Caprini (for surgical patients) 5, and Khorana (for cancer-associated VTE) 5. These are completely separate from VEXUS.