ASH 2019 Guidelines for Surgical Prophylaxis

These evidence-based guidelines from the American Society of Hematology (ASH) intend to support decision making about preventing VTE in patients undergoing surgery.

ASH formed a multidisciplinary guideline panel balanced to minimize bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic reviews. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

Major surgery: The panel suggests pharmacological or mechanical prophylaxis (conditional recommendation). For patients not receiving pharmacologic prophylaxis, mechanical prophylaxis is suggested over no prophylaxis (conditional recommendation). Intermittent compression device is suggested over graduated compression stocking (conditional recommendation). The use of combined prophylaxis or mechanical prophylaxis alone would depend on risk for VTE and bleeding based on individual patient and type of surgery (conditional recommendation). The panel suggests against using inferior vena cava filters for VTE prophylaxis (conditional recommendation). Use of extended over short-term antithrombotic prophylaxis is suggested (conditional recommendation). The panel further suggests using early or delayed antithrombotic prophylaxis (conditional recommendation). For major general surgery the panel suggests pharmacological prophylaxis using low-molecular-weight heparin (LMWH) over no pharmacological prophylaxis (conditional recommendation). The panel suggests against pharmacological prophylaxis in patients undergoing laparoscopic cholecystectomy (conditional recommendation).

Orthopedic surgery: The panel suggests aspirin or anticoagulants in patients undergoing total knee/hip arthroplasty (conditional recommendation). [ Among anticoagulants, direct oral anticoagulants (DOACs) are suggested over LMWH (conditional recommendation). If DOACs are not used, LMWH is suggested over warfarin (conditional recommendation) and LMWH is recommended rather than unfractionated heparin ([UFH]; strong recommendation).] Pharmacological prophylaxis with LMWH or UFH over no prophylaxis is suggested for patients undergoing hip fracture repair (conditional recommendation).

Major neurosurgery: The panel suggests against using pharmacological prophylaxis (conditional recommendation). For the subset of patients using pharmacological prophylaxis, the panel suggests using LMWH over UFH (conditional recommendation).

Urological procedures: The panel suggests against using pharmacological prophylaxis in patients undergoing transurethral resection of the prostate or radical prostatectomy. For the subset of patients using pharmacological prophylaxis, the panel suggests using LMWH or UFH (conditional recommendation).

Cardiac or major vascular surgery: The panel suggests pharmacological prophylaxis or no pharmacological prophylaxis (conditional recommendation). When pharmacological prophylaxis is used, LMWH or UFH is suggested (conditional recommendation).

Major trauma: For patients with low-to-moderate risk for bleeding, pharmacological prophylaxis is suggested over no pharmacological prophylaxis (conditional recommendation). The panel suggests against pharmacological prophylaxis in patients at high risk for bleeding (conditional recommendation). For patients using pharmacological prophylaxis, the panel suggests using LMWH or UFH (conditional recommendation).

Major gynecological surgery: The panel suggests using pharmacological prophylaxis over no pharmacological prophylaxis and suggests using LMWH or UFH (conditional recommendation).