M . Sancheti et al .: J Extra Corpor Technol 2024 , 56 , 37 – 44 41
Figure 4 . Measurements of biomarkers of platelet activation in Xcoating TM circuit . ( A ) No significant changes were detected in soluble P-selectin levels in collected bovine blood at 5 min , 30 min , and 55 min using the Xcoating TM circuit , with values at each time point falling within ± 2 SD of the mean . All measurements are presented as normalized values over the platelet count for each time point . ( B ) The normalized values for PF4 did not change over time with all values at each timepoint falling within ± 2 SD of the mean . ( C ) Normalized values for GPIIb / IIIa and ( D ) b-TG did not show any significant changes at 5 min , 30 min , and 55 min , but all values fell within ± 2 SD of the mean , indicating minimal intra-variability across technical replicates . ( Mean ± SD , P < 0.05 , five technical replicates ). GPIIb / IIIa : Glycoprotein IIb / IIIa ; PF4 : Platelet Factor 4 ; b-TG : b-Thromboglobulin .
counts ) for soluble P-selectin and PF4 translocation and release transiently but not significantly increased by 30 min , and returned to basal levels , with no statistically significant changes observed at 55 min ( Figs . 4A and 4B ), suggesting that luminal surface of Xcoating TM tubes do not impact the level of soluble P-selectin and PF4 release in circulated blood . On the other hand , normalized values for GPIIb / IIIa showed a significant drop at 55 min in the Xcoating TM circuit ( Fig . 4C ), with no significant changes observed for b-TG levels in the circulated blood at any time points ( Fig . 4D ). In addition , statistical analyses were performed using raw values for all four biomarkers secretion and platelet surface levels without normalization over the platelet counts in bypassed bovine blood at 5� , 30� , and 55-minutes in Xcoating TM bypass circuit ( Supplementary Fig . S2 ). A summarized version of all collected values for platelet activation markers in circulated bovine blood is also presented in Table 1 .
Discussion
A cardiopulmonary bypass is a machine that allows for a surgical field suitable to perform open heart surgery , however , it is not devoid of complications [ 1 ]. CPB-induced SIRS affects up to 10 % of patients and can lead to hypoperfusion , embolization , multiple organ failure , and death [ 13 ]. Several proinflammatory pathways work synergistically to cause tissue destruction , and abnormal bleeding [ 13 ]. Platelets are known to bind damaged blood vessels and cause coagulation [ 4 ]. Therefore , in cases of serious complications like CPB-induced SIRS , dysfunctional platelets are the likely reason for organ damage and excessive bleeding . Modern technology has introduced heparin-coated and PMEA-coated circuits to reduce platelet activation and control some of the complications associated with CPB . However , there is no established and well-controlled in vitro protocol that allows for the accurate