Abstract
Background
Venous thromboembolism (VTE) is considered a complication of free flap surgery. Prior
studies investigating the use of the Caprini Risk Score (CRS) to estimate the risk
of complications in free flap reconstruction are confounded by small sample sizes,
varying surgical sites, and disparate classification of risk. This study evaluates
the predictive merit of CRS for complications in free flap reconstructions.
Methods
A retrospective review of patients (n = 502) who underwent free flap reconstruction from January 2015 to April 2022 collected
patient medical history, type and location of free tissue transfer, CRS, and prior
and perioperative anticoagulation (AC). Reconstructive outcomes and complications
were analyzed in low (CRS <8) and high (CRS ≥8) cohorts using chi-square tests. Complications
were also analyzed by flap sites in sufficient cohort populations (n > 10).
Results
Of 502 patients, the high CRS cohort (n = 71) was associated with upper (p < 0.005) and lower (p < 0.001) extremity reconstructions while the low CRS (n = 431) cohort was associated with breast reconstructions (p < 0.001). The high CRS cohort demonstrated an increased need for intraoperative blood
transfusions (p < 0.001). Other intraoperative or postoperative complications such as flap loss,
intraoperative AC, return to operating room (OR), or VTE had no significant correlations.
High CRS patients were more likely to be discharged on AC (p < 0.001) and have a longer length of stay (LOS; p < 0.001). By flap site, there was a significant association between CRS and LOS >14
days in breast and head and neck flaps (p < 0.05) and discharge on AC in head and neck flaps only (p < 0.001).
Conclusion
CRS may have utility in predicting the need for blood transfusion and AC requirements
in free flap reconstruction but does not seem to predict the incidence of flap complications.
A larger, higher-powered study may be used to assess the validity of CRS in risk of
VTE and anticoagulant prophylaxis.
Keywords
Caprini Risk Score - free flap reconstruction - free flap complications