Peri-operative Aspirin Continuation Versus Discontinuation

Study Overview
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Brief Summary
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This study evaluates the continuation (non-discontinuation) of Aspirin during TURBT. Half of participants will continue their usual low-dose Aspirin regimen during TURBT and throughout the perioperative period, while the other half will discontinue Aspirin use ten days prior to surgery (standard recommendation) and restart therapy two weeks post-discharge.

Detailed Description
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Recently, the American College of Chest Physicians in their 2012 clinical guidelines on perioperative anti-thrombotic therapy associated TUR of bladder tumour (TURBT) with an increased risk of bleeding associated with anti-thrombotic therapy. Despite this, contemporary series of TURBT identify the rate of significant in-hospital postoperative bleeding at only 2-3.4%. Previous prospective work by our group demonstrated no increase in postoperative hemorrhagic complications with early initiation of Aspirin following TURBT. These findings are supported by a recent retrospective work on TURBT showing a similar complication profile between continued perioperative antiplatelet therapy and antiplatelet naive patients. The risk associated with Aspirin withdrawal prior to surgery, including increased thrombogenicity, has been extensively studied. Following cessation of Aspirin, full platelet recovery is expected within 12-14 days, however, hemostasis may be regained with as little as 20% of normal platelet activity. Further, evidence supports a platelet rebound phenomenon in the setting of acute Aspirin withdrawal and a resultant clinical prothrombotic state, with thrombotic events peaking ten days following drug cessation. Finally, the acute stress response postoperatively is well known; one component being hypercoagulability which lasts at least seven days after major and uneventful abdominal surgery, predominantly caused by increased platelet activity. Whereas TURBT generally carries a low overall risk of cardiac morbidity, the general requirement to discontinue Aspirin pre-operatively potentially increases certain patients' cerebrovascular or cardiac risk (eg. post-coronary stent placement). As shown above, the risk of significant post-operative hematuria is minimal, and as such, Aspirin withdrawal may be unnecessary. We will perform a prospective, randomized controlled trial to address the safety and tolerability of continued Aspirin use during TURBT.

Official Title
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Must Aspirin be Discontinued Prior to TURBT: a Prospective, Randomized, Non-inferiority Trial Comparing Peri-operative Aspirin Continuation Versus Discontinuation.

Conditions
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Hematuria, Urinary Bladder Neoplasms

Intervention / Treatment
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* Drug: Aspirin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults aged 18 years and older with the ability for self-consent, referred for elective TURBT, receiving low-dose daily Aspirin prophylaxis. Exclusion Criteria: known coagulopathy or abnormal coagulation profile (prothrombin time, partial thromboplastin time, or platelet count), receiving other anti-thrombotic, anti-coagulant, or non-steroidal anti-inflammatory medication (NSAIDs), pregnancy.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Aspirin continuation<br>Continued use of Acetylsalicylic acid at prior dosage (75mg or 100mg tablet one-per-day). | Drug: Aspirin<br> <br> * Other names: Acetylsalicylic acid;|
| No Intervention: Aspirin discontinuation<br>Discontinuation of Acetylsalicylic acid ten days prior to surgery, and re-initiation two weeks after hospital discharge. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Significant hematuria (composite endpoint) | (Composite endpoint): 1. Requiring bladder catheter drainage (after catheter removal), 2. requiring re-hospitalization, 3. requiring operative intervention (ie. cystoscopy +/- transurethral fulguration). Each sub-element within the composite endpoint will receive a binary score [0,1] to denote occurrence. Similarly, the primary endpoint is a binary measure indicating occurrence of any sub-element. Sub-elements 1-3 (re-cath, re-hospitalization, or cystoscopic intervention) may occur at any point throughout the followup period. | Post-operative admission period until 45 days post-discharge. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to urinary catheter removal | Measured in post-operative days, from the time of surgery until catheter removal (typically during post-operative admission period). | up to 45 days | 
| Withholding or withdrawal of Aspirin | A binary measure [0,1]. In the control group (Aspirin restarted two weeks post-discharge), if Aspirin is withheld due to continued hematuria, this will constitute an event. Similarly, in either group, if Aspirin is withdrawn at any point post-operatively due to hematuria, this will constitute an event. | up to 45 days | 
| Time to urine clearance | Measured in postoperative days until any lingering, sporadic macrohematuria has resolved. Patients will be discharged with a Hematuria Grading Scale based on that developed by Lee et al, a VAS-like scale of hematuria intensity (redness), and will note their most intense hematuria level on a daily basis until urine clearance. It is assumed that postoperative macrohematuria will resolve by 45 days postoperatively, the duration of followup. | up to 45 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Aspirin usage, Transurethral resection of bladder tumor (TURBT)