Aspin: Neurosurgical Aspirin Intervention Prognostic Study; perioperative continuation versus discontinuation of aspirin in spinal surgery, a randomized controlled, noninferiority trial.
Authors: Zian Ahmed , Moojen Wouter A , Gaag Niels A van der , Overdevest Gijsbert M , Schutte Pieter J , Klok F.A. 
Published: January 2023

Abstract
Rationale:
Aspirin is typically discontinued in cranial and spinal surgery because of increased risk of hemorrhagic complications, but comes together with the risk of resulting in an increase of cardiac and neurologic thrombotic perioperative events.
Objective:
The aim of this study is to investigate the non-inferiority of perioperative continuation of aspirin patients undergoing low complex lumbar spinal surgery, compared with the current policy of perioperative discontinuation of aspirin.
Study design: A randomized controlled trial with two parallel groups of 277 cases (554 in total)
Study population: Patients undergoing low complex lumbar spinal surgery and using aspirin. All patients are aged >18 years.
Intervention: Peri-operative continuation of aspirin.
Study outcomes:
Primary study outcome: composite of the following bleeding complications:
- Neurological deterioration as a result of haemorrhage in the surgical area with cauda and/or nerve root compression.
- Post-surgical anaemia with haemoglobin-level lower than 5 mmol/l, requiring transfusion.
- Subcutaneous haematoma leading to wound leakage and pain higher than NRS=7.
- Major and/or minor haemorrhage in any other body system according to the definition of the International Society on Thrombosis and Haemostasis bleeding scale.
Secondary study outcomes:
- Each of the individual components of the primary outcome
- Absolute mean difference in operative blood loos between the study arms
- Thrombo-embolic related complications:
- Myocardial infarction
- Venous thromboembolism
- Stroke
- Arterial thromboembolism
Further study outcomes:
Anticoagulant treatment satisfaction by the Anti-Clot Treatment Scale (ACTS) and general health by the Patient-Reported Outcomes Measurement Information System (PROMIS Global-10) in the pre- and postoperative phase.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness:
Participation in this study imposes no additional risk to patients. Currently, there is no consensus whether or not aspirin should be discontinued before cranial or spinal surgery.
Currently, aspirin is typically discontinued in cranial and spinal surgery, because of a potential increased risk of hemorrhagic complication. An argument not based on a clinical trial. However, this policy might delay surgical procedures or and carries the risk of resulting in an increase of cardiac and neurologic thrombotic perioperative events. It is unclear if the possibility for an increase of hemorrhage related complications outweighs the risk of an increase of cardiac and neurologic thrombotic perioperative events.
Furthermore, the Data Safety Monitoring Board (DSMB) will be asked for safety-analysis by monitoring the study.
There are no further disadvantages of participating in this study. Outcome measurements are recorded during admission and regular outpatient visits, and thus, do not require additional visits to the hospital.