Comparison of Caprini and Worcester Scores for Venous Thromboembolism Risk Stratification in the Setting of Ambulatory Endovenous Surgery

Abstract

Introduction

Post-operative venous thromboembolism (VTE) remains a significant concern after endovenous ablation (EVA) for varicose veins. Risk stratification tools aid identifying which patients have an increased VTE risk. There is no consensus on which currently utilised score is most appropriate for daycase surgery. The aim of this observational study was to compare how 2 institutions utilised the Caprini and Worcester Scores to risk stratify ambulatory EVA patients in real-world practice.

Methods

A retrospective review of consecutive patients undergoing truncal ablation under local anaesthetic in 2 separate vascular centres between 2022-23 was performed. Each patient was scored prospectively using either the Caprini and Worcester Score for perioperative VTE risk assessment, and then retrospectively using the alternate tool. Demographics and risk factors were documented and compared between patients categorised as “at risk” by each score. Categorical variables were analysed using Chi-Square and continuous using Mann-Whitney U Tests.

Results

Two hundred patients undergoing endovenous ablation were included. Over half the cohort were female (n = 122, 61%) and the median age was 53.0 years (range 23-87). Twenty-one percent (n = 42) had a Body Mass Index (BMI) > 30. Overall, 90 patients were flagged as high-risk by either score. Fifty-three patients (26.5%) were flagged by the Worcester Score as either ‘moderate’ (n = 42, 21%) or ‘high risk’ (n = 11, 5.5%). Fifty-eight patients (29%) were identified as ‘high risk’ by the Caprini tool. A significant discrepancy in which patients were categorised as “at risk” by each score was noted, with only 21 patients stratified as “at risk” by both (P = 0.047).

Conclusions

A similar proportion of patients were stratified as high risk by each score, however the lack of overlap between the 2 risk assessment tools suggests a discrepancy in what variables are scored for. Further well-powered studies are needed to validate which score is most appropriate for ambulatory EVA.