Components of the Caprini Score for VTE Risk Assessment
The Caprini Risk Assessment Model (RAM) is a validated tool that stratifies patients into venous thromboembolism (VTE) risk categories based on multiple risk factors, with higher scores correlating with increased VTE risk. 1, 2
Risk Factors Included in the Caprini Score
The Caprini score includes the following components:
Patient Demographics and History
- Age >60 years (1 point) 3
- Previous VTE (3 points) 3, 4
- Known thrombophilia (3 points) 3
- Body mass index ≥35 kg/m² (1 point) 3
Medical Conditions
- Active malignancy (2 points for stomach/pancreas; 1 point for lung, lymphoma, gynecological, genitourinary; 1 point for breast, colorectal, head and neck) 3
- Acute infections (1 point) 3, 4
- Acute paresis (2 points) 3
- Critical illness (1 point) 3
- Immobility (1 point) 3, 4
Laboratory Values
- Pre-chemotherapy platelet count ≥350 × 10⁹/l (1 point) 3
- Hemoglobin <10 g/dl or use of erythropoiesis-stimulating agents (1 point) 3
- Leukocyte count >11 × 10⁹/l (1 point) 3
Surgical and Procedural Factors
- Major surgery (varies by type)
- Central venous catheter presence (1 point) 3
Risk Stratification Using Caprini Score
The Caprini score stratifies patients into risk categories:
- Low risk: 0-1 points
- Moderate risk: 2 points
- High risk: 3-4 points
- Highest risk: ≥5 points 2
Studies have shown that further stratification of the highest risk group provides additional clinical information:
- Score 5-6: 3.33-fold increased risk of VTE
- Score 7-8: 9.41-fold increased risk of VTE
- Score ≥9: 24.69-fold increased risk of VTE 2
Clinical Application
The Caprini RAM has demonstrated superior sensitivity (96%) and specificity (92.1%) compared to other risk assessment models like the Padua score (64.3% and 46.9%, respectively) 4. This makes it a valuable tool for identifying patients who would benefit from thromboprophylaxis.
Important Considerations
- The Caprini score is designed to predict VTE risk at 30 days after assessment, though many studies report outcomes at varying timepoints 1
- There is some variability in how the Caprini score is implemented across different centers, including differences in cutoff points defining risk categories 1
- Beyond VTE prediction, higher Caprini scores have been associated with increased risk of other postoperative complications including dehiscence, infection, necrosis, seroma, and hematoma 5
The Caprini RAM provides a systematic approach to VTE risk assessment that can guide appropriate thromboprophylaxis decisions, potentially reducing morbidity and mortality associated with hospital-acquired VTE.