Caprini Vte Score Calculator

The Caprini model is an additive risk assessment tool that operationalizes Virchow's triad, the nineteenth century observation that thrombosis arises from stasis, endothelial injury, and hypercoagulability. Roughly 40 risk factors are grouped into four weight tiers according to how strongly each is associated with postoperative venous thromboembolism. One point items are mostly stasis and mild hypercoagulability contributors such as age 41 to 60, BMI above 25, varicose veins, pregnancy or postpartum status, hormone use, sepsis, heart failure, and bed rest. Two point items include age 61 to 74, major surgery lasting more than 45 minutes, malignancy, immobilizing cast, and bed rest beyond 72 hours. Three point items capture strong hypercoagulability: age 75 or older, prior or family history of VTE, factor V Leiden, prothrombin 20210A mutation, lupus anticoagulant, anticardiolipin antibodies, and heparin-induced thrombocytopenia. Five point items are the major trauma and orthopedic events, namely stroke, elective arthroplasty, hip or pelvic fracture, spinal cord injury, and multiple trauma. The total maps to escalating prophylaxis intensity rather than to a diagnosis. A score of 0 corresponds to symptomatic VTE incidence below roughly 0.5 percent and needs only early ambulation; 1 to 2 is low risk warranting mechanical prophylaxis with intermittent pneumatic compression; 3 to 4 is moderate, typically prompting low molecular weight heparin or low-dose unfractionated heparin; and 5 or above is high risk, where combined pharmacologic and mechanical prophylaxis and sometimes extended post-discharge prophylaxis for 28 to 35 days are considered. The model deliberately says nothing about bleeding risk, which must be weighed separately, and it was derived in general, vascular, and plastic surgery populations, so it performs less well in medical inpatients and in orthopedic patients whose baseline risk is already high enough to warrant prophylaxis regardless.

Joseph Caprini, a vascular surgeon who worked at Evanston Northwestern Healthcare and Northwestern University in Illinois, introduced the model with colleagues in the early 1990s, with a foundational description appearing in Seminars in Thrombosis and Hemostasis in 1991. The motivation was practical. Autopsy and screening venography studies of the 1970s and 1980s had shown that deep vein thrombosis was common after surgery and frequently silent, and that fatal pulmonary embolism was among the leading preventable causes of in-hospital death, yet prophylaxis was applied inconsistently because surgeons had no structured way to distinguish a low-risk day-case patient from a high-risk one. Caprini revised the weights in 2005, expanding the factor list and refining tier assignments. The pivotal external validation came from Vinita Bahl and colleagues at the University of Michigan, published in Annals of Surgery in 2010, which applied the 2005 model retrospectively to more than 8,000 general, vascular, and plastic surgery patients and demonstrated a clear stepwise gradient in 30-day VTE incidence across score strata. Subsequent validations followed in plastic and reconstructive surgery by Pannucci and colleagues, in otolaryngology, and in urology. The American College of Chest Physicians incorporated Caprini-based stratification into the ninth edition of its antithrombotic therapy guidelines in 2012, which cemented the score in routine preoperative documentation and in hospital quality programs in the United States and Europe.