Bleeding risk assessment in acute aortic dissection type A using platelet aggregometry

Acute aortic dissection type A (AADA) is a life-threatening surgical emergency with high mortality. Use of antiplatelet drugs and/or platelet dysfunction are associated with higher rates of postoperative morbidity and mortality.1 However, studies on impact of platelet dysfunction in this patient group is limited. The aim of this study was to determine the relationship between preoperative platelet function assessed by Multiplate® aggregometry and transfusion requirement. Patients and methods This prospective observational study included 180 patients over a two-year period (2019–2021) who underwent emergency surgical repair of AADA. AADA patients with iatrogenic causes (n = 8) were excluded. Platelet function was evaluated prior to surgery using Multiplate® analyzer and three activators, namely adenosine diphosphate (ADP test), arachidonic acid (ASPI test) and thrombin receptor-activating peptide-6 (TRAP test). Platelet aggregometry is used to assess the effect of antiplatelet drugs such as Aspirin (ASPI test), ADP-antagonists like clopidogrel (ADP test) and GpIIbIIIa receptor antagonists (TRAP test). The number of blood products transfused, need for surgical re-exploration, length of hospital stay, mortality and survival were compared. Results An abnormal aggregation response was observed in 88 (48.9%) patients using ASPI test, in 43 (23.9%) patients using ADP test and in 112 (62.2%) patients using the TRAP test. 31 (17.2%) patients had an abnormal response to all three tests. Preoperative Aspirin use was reported in 35 (19.4%) while clopidogrel use was reported in 7 (3.9%). Patients with low ASPI response received more red cell concentrates (9.5 ± 7.3 vs 6.2 ± 4.5, p = 0.007) and platelet concentrates (5.9 ± 3.5 vs 4.8 ± 2.7, p = 0.038) whereas patients with low ADP tests received more red cell concentrates (9.6 7.2 vs 7.1 5.7, p = 0.014). There were no statistically significant differences in the need for surgical re-exploration, the total length of hospital stay, mortality, or survival time. Conclusion Our results show that AADA patients with abnormal aggregation response require more red cell and platelet concentrate transfusions. Multiplate® aggregometry can be a useful indicator of platelet dysfunction and bleeding risk in AADA patients.