Background: Venous thromboembolism (VTE) is a common complication after major surgeries, including general, orthopedic, gynecologic, trauma, and neurosurgery despite specific prophylaxis recommendations. Validating the Caprini risk assessment model in patients post coronary artery bypass graft (CABG) surgery will not only be able to predict the likelihood of the occurrence of deep vein thrombosis but can aid in arriving at a consensus regarding proper thromboprohylaxis strategy in patients undergoing elective CABG surgery at our institution.
Methods: Patient ages 19-80 years old who underwent elective CABG surgery at the Philippine Heart Center were included in the study. Each patient was stratified preoperatively using the Caprini Risk Assessment model. Deep vein thrombosis screening was done on the third to fifth post-operative day. The incidence and clinical predictors for lower extremity deep vein thrombosis were determined based on those patients who were positive for acute deep vein thrombosis.
Results: A total of 101 patients were included in the study, 100 in the negative group and 1 in the positive group. Only one patient was positive for deep venous thrombosis. Majority of the subjects who were negative for DVT were males (84%) with history of smoking (61%). Hypertension is the most common co-morbidity followed by diabetes mellitus and hypercholesterolemia. The average number of hospital days pre-operatively was 3.31 ± 2.9 days. All of the patients had no history of DVT prophylaxis and were ambulatory preoperatively except for one subject who had a temporary intravenous pacemaker. The mean immobilization time post-operatively was 3.27 ± 0.63 days. Early ambulation was the form of VTE prophylaxis in all patients.
Conclusion: The incidence of deep venous thrombosis after coronary artery bypass surgery is 1% in our setting. Despite its low incidence, it can still lead to non-fatal and fatal pulmonary embolism which can increase the morbidity and mortality as well as hospital costs. The use of Caprini risk assessment model in predicting post-op DVT in post CABG surgery patients has limited value since despite the high post-op Caprini score of patients, only 1 patient turned out to be positive. However, the Caprini Risk Assessment model is still a useful tool that will guide clinicians in risk stratifying patients thereby providing the appropriate prophylaxis regimen that could lower the incidence of post-op DVT in those who are undergoing CABG surgery.