Clinical Post-operative Bleeding During Minor Oral Surgical Procedure and In Vitro Platelet Aggregation in Patients on Aspirin Therapy: Are they Coherent?

AIM: The risk of excessive bleeding prompts physicians to discontinue aspirin in patients on low-dose, long-term therapy which in turn puts them at the risk from adverse cardiovascular and thrombotic events. Effect of low-dose aspirin therapy on platelet function was assessed using platelet aggregation method. The aim was to correlate the laboratory platelet function with cutaneous and clinical oral bleeding time (BT).
MATERIALS AND METHODS: One hundred one patients were enrolled in this prospective trial and were allocated into two groups. Interventional or test group consisted of patients who were on aspirin therapy (75 mg/100 mg) for primary or secondary prevention of angina, myocardial infarction and stroke. Minor oral surgical procedure was performed in this group without discontinuing aspirin therapy. Control group consisted of healthy patients (under no medication) undergoing minor oral surgical procedure. Cutaneous and clinical oral BT were recorded in both the groups. Venous blood sample was drawn, and percentage platelet aggregation function was analysed using adenosine diphosphate (ADP) and arachidonic acid (AA) reagents. The percentage of platelet aggregation was then correlated with cutaneous and clinical oral BT.
RESULTS: A significant decrease in percentage platelet aggregation using ADP (aspirin-74.7 21.39; control-89.2 13.70) and AA (aspirin-47.6 23.11; control-82.3 20.17) was observed. However, there were no significant difference in mean cutaneous BT (aspirin-1.5 0.65 min; control-1.6 0.71 min) and clinical oral BT (aspirin-5.0 2.48 min; control-4.8 2.60 min) in aspirin and control groups.
CONCLUSION: Majority of the minor oral surgical procedures can be carried out safely without discontinuing aspirin in patients on low-dose long-term therapy. This is possible because despite significant platelet aggregation evident in laboratory evaluation there is lack of its clinical corroboration owing to aspirin resistance. CLINICAL TRIAL REGISTRATION: CTRI/2018/02/012055. © The Association of Oral and Maxillofacial Surgeons of India 2020.