Platelets Count During Circulatory Assistance: Involvement in the Changes of Oxygenation Membrane

Background To study the evolution of platelet count during patient treatment with Extra-Corporeal Membrane Oxygenation (ECMO) and the causes of Membrane Oxygenation (MO) exchange. Assessment of the morbidity and mortality rate was our secondary objective. Methods A single center retrospective study was conducted from January 2014 to December 2015. One-hundred and thirty-nine MO exchanges were studied over 73 patients who received 66 MO exchange. Alterations in biological parameters were compared before and after each MO exchange, to study the device-related platelet count evolution. Results Mean patient age was 56.8±13.4 years. The mean duration of the MO was 5.9±3.1 days, exchanged 26 times (68%) after clot formation. The median Survival After Veno-arterial ECMO score (SAVE score) was -3.5 [-4; -1] interquartile range [IQR]. The median Respiratory Extra-corporeal membrane Oxygenation Survival Prediction score (RESP score) was -1 [-3; 0] [IQR]. A significant decrease (p<0.001) in platelet count between the first and second MO exchange was observed in comparison with the baseline. Yet a steady decline was noted after the third MO exchange, afterwards, normalization was observed after ECMO weaning. During ECMO, a decrease in platelet count from the baseline was found after the first MO on day 2 (p<0.001), the delta was 58.000±19.000 //µL, followed by an additional significant decrease on day 3 (p=0.001). The average platelet transfusion was 0.6±1.4 units. Interestingly, the more MO was exchanged, the lesser blood products transfusion was done. The overall mortality rate was 39%; in Veno- Arterial ECMO (VA-ECMO) it was 34.48% and 41.38% in Veno-Venous ECMO (VV-ECMO). Conclusion Clot formation is the leading cause of MO exchange during ECMO. Therefore, there is a significant decrease in platelets count starting from day 2 that indicates platelets transfusions in order to prevent complications of hemostasis.