Impact of Surgery Type and Co-Morbidities on Venous Thromboembolism prophylaxis Practices in Patients Undergoing Major Surgical Procedures in Acute Care Hospitals Worldwide: A Subanalysis of Data from the ENDORSE Survey
Authors: Kakkar Ajay K , Cohen Alexander T , Tapson Victor F , Bergmann Jean-Francois , Goldhaber Samuel Z. , Anderson Frederick A 
Published: April 2020

Abstract
Introduction: Despite the publication of international consensus guidelines for the provision of venous thromboembolism (VTE) prophylaxis, the recent ENDORSE survey reported that 64% of patients admitted to surgical wards in hospitals worldwide are at risk for VTE, and of those only 59% received appropriate prophylaxis (Lancet2008;371:387–94). In this sub-analysis of ENDORSE data, we assess the provision of VTE prophylaxis according to surgery type, and evaluate the key factors associated with the decision to provide VTE prophylaxis to surgical patients.
Methods: ENDORSE was a multinational, cross-sectional survey of patients admitted to medical and surgical wards in 358 hospitals across 32 countries (Lancet2008;371:387–94). VTE risk and prophylaxis use were assessed in evaluable patients according to the 2004 American College of Chest Physicians (ACCP) guidelines (Chest2004;126:338S–400S). Major surgery was grouped into the following categories: major orthopedic (hip replacement, knee replacement, hip fracture repair); abdominal/thoracic (colon/small bowel, rectosigmoid, gastric, hepatobiliary, thoracic); vascular; urological/gynecological; and other (curative arthroscopy, other orthopedic trauma, other surgeries). Independent factors associated with the use of ACCP-recommended prophylaxis in surgical patients at risk for VTE were evaluated using multivariable logistic regression analyses.
Results: Of the 30,827 patients in surgical wards included in ENDORSE, 18,461 had undergone major surgery as of the date of the survey. Of these, 17,018 (92.2%) were considered to be at risk for VTE, although only 10,710 (58.0%) received ACCP-recommended types of VTE prophylaxis. The proportion of patients at risk for VTE and the use of ACCP-recommended prophylaxis varied according to surgery type (Table). Multivariable analysis confirmed that surgery type was the factor that was most strongly associated with the provision of ACCP-recommended VTE prophylaxis. Patients undergoing major orthopedic surgery were most likely to receive recommended VTE prophylaxis, with patients undergoing hip replacement surgery 6 times more likely to receive ACCP- prophylaxis (OR 6.2; 95% CI 5.0–7.9). Curative arthroscopy and rectosigmoid surgery were also strongly associated with the provision of ACCP-recommended prophylaxis: (OR 3.6; 95% CI 2.3–5.4 and OR 2.3; 95% CI 1.7–3.0, respectively). When surgery type was excluded from the multivariable analysis, obesity (OR 1.9; 95% CI 1.7–2.1), rheumatologic or inflammatory disease (OR 1.7; 95% CI 1.3– 2.2), and previous VTE (OR 1.7; 95% CI 1.3–2.1) were the clinical characteristics most strongly associated with the use of recommended VTE prophylaxis.
Conclusion: The provision of ACCP-recommended VTE prophylaxis was primarily driven by the fact that patients underwent a major operation and rates of prophylaxis use varied substantially according to the type of surgery. Patients undergoing major orthopedic surgery are most likely to receive appropriate VTE prophylaxis, however up to 45% of at-risk patients undergoing non-orthopedic procedures do not receive ACCP-recommended prophylaxis. Surgery type was the most important factor associated with the decision to provide ACCP-recommended prophylaxis in surgical patients at risk for VTE.
Table: Prevalence of VTE risk and use of ACCP-recommended prophylaxis according to surgery type.
Surgery type N Patients at risk For VTE n (%) At-risk receiving ACCP-Recommended prophylaxisn (%) Major orthopedic 2300 2300 (100) 1979 (86.0) Abdominal/thoracic 5028 4527 (90.0) 3023 (66.8) Vascular 1038 946 (91.1) 676 (71.5) Urological/gynecological 2653 2344 (88.4) 1261 (53.8) Other 7442 6901 (92.7) 3771 (54.6)