Comparative Analysis of Perioperative Anticoagulation Management Guidelines across U.S. Institutions
Authors: Singh Rishabh , Cogan Jacob , Cromwell Caroline , Gaddh Manila , Gangaraju Radhika , Lim Ming Y , Morton Colleen T. , Peseski Andrew M. , Rosovsky Rachel P. , Tatake Ishan J , Youkhana Kimberley , Baumann Kreuziger Lisa 
Published: December 2024

Introduction
Guidelines for perioperative management of oral anticoagulants exist to balance the risk of bleeding against thromboembolism. We evaluated the implementation of international guidelines into US hospital guidelines.
Methods
The Systems-Based Hematology Committee of the Venous ThromboEmbolism Network US (VENUS) compared perioperative guidelines from represented institutions. Recommendations were grouped based on the type and dose of anticoagulant, bleeding risk of the procedure, and whether adjustments were made for renal insufficiency. Data was abstracted by two reviewers to ensure accuracy.
Results
Guidelines from 11 academic institutions in different states were reviewed for the perioperative management of warfarin, unfractionated heparin (UFH), low molecular weight heparin (LMWH), direct oral anticoagulants (DOACs), and fondaparinux.
For warfarin, 82% (9/11) of institutions recommend to hold/stop/discontinue anticoagulation 5 days before surgery, while 18% (2/11) specify the last dose day as either day -6 or day -5. One institution recommends cessation for 5-6 days. After surgery, 45% (5/11) recommend restarting warfarin 12-24 hours postoperatively if hemostasis is adequate, one institution considers restarting on day 0 and definitively by day +1, and 27% (3/11) did not specify when to restart warfarin.
All institutions alter recommendations for DOAC management based on procedure-related bleeding risk. 82% (9/11) of institutions adjust recommendations based on renal function for all DOACs, while 18% (2/11) only adjust for patients taking dabigatran. 73% (8/11) institutions use “hold” to describe management whereas “stop”, “no dose”, and “last dose” are used in the other 27% (3/11) of guidelines. For standard bleeding risk procedures with normal renal function, 73% (8/11) institutions hold rivaroxaban or apixaban for 24 hours/1 day prior to the procedure and 27% (3/11) institutions recommend not to take for 2 days. For high bleeding risk procedures, guidelines varied significantly with differentiation between agent and renal function. Postoperative restart of DOACs are recommended at 24 hours for standard bleeding risk procedures and 48-72 hours for high bleeding risk procedures by 55% (6/11) of institutions. One institution suggests restarting as soon as hemostasis is achieved and another advising to wait at least 4-6 hours with hemodynamic stability.
For prophylactic UFH, one institution starts anticoagulation 2 hours before non-orthopedic surgery, 18% (2/11) continue anticoagulation without interruption, 36% (4/11) hold anticoagulation 4-6 hours before surgery, 9% (1/11) hold one dose for high bleeding risk procedures, and 27% (3/11) do not specify preoperative holding. For therapeutic UFH, 64% (7/11) of institutions recommend stopping or holding therapeutic heparin 4-6 hours prior to surgery, 18% (2/11) recommend holding for 4 hours, and 9% (1/11) suggest holding for more than 6 hours. Only 45% (5/11) of institutions recommend when to restart prophylactic UFH postoperatively, and 55% (6/11) for therapeutic UFH.
Institutions agreed more for LMWH management. For prophylactic LMWH, 64% (8/11) recommend holding LMWH 12 hours before procedures, with one noting a 12-24-hour range. For therapeutic LMWH, 82% (9/11) of institutions recommend holding 24 hours preoperatively with 33% (3/9) mention administering half the total morning dose for daily dosing. Seven institutions provided restarting instructions for LMWH, and recommendations were grouped by bleeding risk of the procedure. For standard risk bleeding procedures, all seven institutions recommended restarting LMWH at 24 hours postoperatively while all seven institutions recommend restarting at 48-72 hours for high bleeding risk procedures.
For prophylactic fondaparinux, 3/11 institutions (27.3%) hold for 24 hours, and 2/11 (18.2%) hold for 48 hours prior to the procedure, with renal adjustments made in three guidelines. 3/11 (27.3%) do not distinguish between recommendations for therapeutic and prophylactic fondaparinux, while 7/11 (63.6%) recommended holding therapeutic for 3-4 days.
Conclusion
Despite international guidelines for perioperative management of anticoagulation, institutions vary in management and language used in guidelines. Efforts are needed to understand if this variability impacts patient outcomes and to find ways to improve guideline implementation.