Aspirin and spinal haematoma after neuraxial anaesthesia: Myth or reality?

The safety of aspirin therapy in neuraxial anaesthesia has been historically questioned, and the current recommendations are still heterogeneous. A comprehensive review of clinical evidence and a comparative analysis of European and American guidelines were performed. Low-dose aspirin produces a selective, complete and irreversible cyclooxygenase-1 blockade, and higher doses do not increase the antiplatelet effect. Additional cyclooxygenase-2 blockade by high-dose aspirin might decrease the antithrombotic efficacy by inhibiting endothelial prostacyclin synthesis. Different doses of aspirin have been shown to be safe in a broad population subjected to neuraxial anaesthesia or analgesia. In the few case reports of spinal haematoma involving aspirin therapy, additional complicating factors were present. Considering the available evidence, the majority of national scientific societies agree that the isolated use of aspirin does not increase the risk of spinal haematoma and does not represent a contraindication to neuraxial blocks. The precautions regarding higher doses do not seem to be justified. Although aspirin alone is considered to be safe in neuraxial anaesthesia, the concurrent administration of other antithrombotic drugs significantly increases the risk of spinal haematoma and the recommended safety times for each of these other drugs must be strictly followed. An individualized assessment of the risks and benefits should be performed, before performing a neuraxial technique or catheter removal in a patient receiving aspirin.