2 – Should aspirin be stopped pre-operatively in patients undergoing orthopaedic procedures?

Marcelo Lizarraga, Suhail Suresh, Takahiro Niikura, Luis Elías, Marzaid Manzaneda, Juan Carlos Castro, Miguel S. Egoavil, Sara L.Whitehouse, Ross W. Crawford.

Response/Recommendation: Aspirin (ASA), administered for cardiovascular reasons, should not routinely be stopped in patients undergoing orthopaedic procedures. Continuation of ASA is likely to be cardioprotective and unlikely to be associated with increased blood loss.

Strength of Recommendation: Limited.

Rationale: ASA has been shown to be effective for secondary prevention of cardiovascular diseases (CVD) and hence is used by a large proportion of the population for primary prevention of CVD1. ASA exerts its beneficial effects by inhibiting the aggregation of platelets. It reduces the risk of vascular death by about one-sixth and the risk of non-fatal myocardial infarction and stroke by about one-third in patients with unstable angina or a past history of myocardial disease2.

Contrary to studies such as the pulmonary embolism prevention (PEP)3 and the Perioperative Ischemia Evaluation – 2 (POISE-2)4 trials that evaluated the effect of ASA on the prevention of venous thromboembolism (VTE) after surgery, the question of whether to stop ongoing treatment with ASA for patients using it as prophylaxis against thrombotic vascular events is still unclear.

Currently, we are in an epidemiological transition with cardiovascular disease being rife in the society. Thus, many individuals are placed on cardioprotective antiplatelet drugs, including ASA5. For those patients with a well-known CVD history, taking ASA may be critical. Thus, stopping ASA preoperatively can cause a platelet rebound phenomenon and prothrombotic state leading to major adverse CVD events6–8. Unless contraindicated, ASA should not be stopped preoperatively in a group of patients at high risk of CVD or at least this issue should be discussed with the patient’s cardiologist. For patients with CVD, the risk of thrombotic events after acute ASA withdrawal is mostly felt to outweigh the risk of bleeding complications following surgery5.

The evidence for ASA having a clinically significant effect on perioperative blood loss is conflicting, with some studies supporting and others refuting such association5,9. One study reports that transfusion rate and ICU admissions were higher in a group on ASA with no cessation of therapy compared to a control group after proximal femoral fracture, although there were no other significant findings10. A more recent study in patients with hip fracture compared 114 patients taking ASA at the time of their fracture surgery to 103 propensity score-matched controls not taking ASA11, and found that taking ASA did not affect peri-operative blood loss or blood transfusion requirements.

The case for elective hip and knee replacement is more unclear and evidence is largely based on specialties other than orthopaedics. One study investigated the cessation or continuation of ASA prior to elective abdominal surgery and concluded that continuing ASA was not associated with excessive bleeding12. Mantz et al., performed a randomized controlled trial, the Strategy for Managing Antiplatelet Therapy in the Perioperative Period of Non-Coronary Surgery (STRATAGEM) trial where 52% of patients were undergoing orthopaedic procedures and compared continuation vs. cessation of ASA 10 days prior to surgery. They reported no significant differences in outcomes of major thrombotic or bleeding events between the groups. However, the trial was stopped early due to recruitment issues, including the publication of recommendations to avoid stopping ASA7,8.

Similarly, Oscarsson et al.13, also attempted to study this subject matter and had to end the recruitment of patients early (220 of planned 540 patients recruited), again largely due to the publication of new recommendations endorsing the continuation of ASA in the perioperative period14–16. In the latter underpowered study, no significant difference in myocardial damage (defined as elevated Troponin T) was seen. The study was also not powered to identify a difference in bleeding complications, and no differences between groups was observed.

Shaw et al.9, found a conflicting result when they performed a retrospective cohort study on 2,853 total hip and knee arthroplasty patients in order to identify whether preoperative dose or time of discontinuation affected surgical outcomes. They determined that patients receiving ASA prior to surgery had an increased risk for readmission and 90-day post-operative events compared to those not receiving ASA, mostly related to lower rate of postoperative complications (such as hematoma formation). Interestingly, the study found that the risk for postoperative complications was also higher in patients who stopped ASA closer to the time of surgery.

In conclusion, the decision to stop ASA or continue it perioperatively depends on many variables including the risk profile of the patients for cardiovascular disease, the nature of surgery, risk and significance of bleeding (intracranial bleed for example), and so on. Based on the available evidence, continuation of ASA in patients undergoing elective procedures does not seem to increase the risk of bleeding or transfusion requirements significantly. Orthopaedic surgeons intending to stop ASA prior to elective procedures may wish to communicate this decision with the cariology team caring for the patient.


1.         Plümer L, Seiffert M, Punke MA, et al. Aspirin Before Elective Surgery-Stop or Continue? Dtsch Arztebl Int. 2017;114(27-28):473-480. doi:10.3238/arztebl.2017.0473

2.         Brunetti S, Petri GJ, Lucchina S, Garavaglia G, Fusetti C. Should aspirin be stopped before carpal tunnel surgery? A prospective study. World J Orthop. 2013;4(4):299-302. doi:10.5312/wjo.v4.i4.299

3.         Prevention of pulmonary embolism and deep vein thrombosis with low dose aspirin: Pulmonary Embolism Prevention (PEP) trial. Lancet. 2000;355(9212):1295-1302.

4.         Eikelboom JW, Kearon C, Guyatt G, et al. Perioperative Aspirin for Prevention of Venous Thromboembolism: The PeriOperative ISchemia Evaluation-2 Trial and a Pooled Analysis of the Randomized Trials. Anesthesiology. 2016;125(6):1121-1129. doi:10.1097/ALN.0000000000001352

5.         Meier R, Marthy R, Saely CH, Kuster MS, Giesinger K, Rickli H. Comparison of preoperative continuation and discontinuation of aspirin in patients undergoing total hip or knee arthroplasty. Eur J Orthop Surg Traumatol. 2016;26(8):921-928. doi:10.1007/s00590-016-1830-7

6.         Gerstein NS, Schulman PM, Gerstein WH, Petersen TR, Tawil I. Should more patients continue aspirin therapy perioperatively?: clinical impact of aspirin withdrawal syndrome. Ann Surg. 2012;255(5):811-819. doi:10.1097/SLA.0b013e318250504e

7.         Collet JP, Montalescot G, Blanchet B, et al. Impact of prior use or recent withdrawal of oral antiplatelet agents on acute coronary syndromes. Circulation. 2004;110(16):2361-2367. doi:10.1161/01.CIR.0000145171.89690.B4

8.         Ferrari E, Benhamou M, Cerboni P, Marcel B. Coronary syndromes following aspirin withdrawal: a special risk for late stent thrombosis. J Am Coll Cardiol. 2005;45(3):456-459. doi:10.1016/j.jacc.2004.11.041

9.         Shaw JH, Kadri OM, Les CM, Charters M. Effect of Acetylsalicylic Acid Dose and Time Discontinued Preoperatively on Outcomes After Total Knee and Hip Arthroplasty. Orthopedics. 2019;42(5):289-293. doi:10.3928/01477447-20190812-01

10.       Jang C-Y, Kwak D-K, Kim D-H, Lee H-M, Hwang J-H, Yoo J-H. Perioperative antiplatelet in elderly patients aged over 70 years treated with proximal femur fracture: continue or discontinue? BMC Musculoskelet Disord. 2019;20(1):124. doi:10.1186/s12891-019-2504-5

11.       Ohmori T, Toda K, Kanazawa T, Tada K, Yagata Y, Ito Y. Retrospective high volume comparative study suggests that patients on aspirin could have immediate surgery for hip fractures without significant blood loss. Int Orthop. 2021;45(3):543-549. doi:10.1007/s00264-021-04941-6

12.       Sahebally SM, Healy D, Coffey JC, Walsh SR. Should patients taking aspirin for secondary prevention continue or discontinue the medication prior to elective, abdominal surgery? Best evidence topic (BET). Int J Surg. 2014;12(5):16-21. doi:10.1016/j.ijsu.2013.11.004

13.       Oscarsson A, Gupta A, Fredrikson M, et al. To continue or discontinue aspirin in the perioperative period: a randomized, controlled clinical trial. Br J Anaesth. 2010;104(3):305-312. doi:10.1093/bja/aeq003

14.       Burger W, Chemnitius J-M, Kneissl GD, Rücker G. Low-dose aspirin for secondary cardiovascular prevention – cardiovascular risks after its perioperative withdrawal versus bleeding risks with its continuation – review and meta-analysis. J Intern Med. 2005;257(5):399-414. doi:10.1111/j.1365-2796.2005.01477.x

15.       Fleisher LA, Fleischmann KE, Auerbach AD, et al. 2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines. Developed in collaboration with the American College of Surgeons, American Society of Anesthesiologists, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Anesthesiologists, and Society of Vascular Medicine Endorsed by the Society of Hospital Medicine. J Nucl Cardiol. 2015;22(1):162-215. doi:10.1007/s12350-014-0025-z

16.       Merritt JC, Bhatt DL. The efficacy and safety of perioperative antiplatelet therapy. J Thromb Thrombolysis. 2004;17(1):21-27. doi:10.1023/B:THRO.0000036025.07348.f1