Impact of minimally invasive extracorporeal circulation on coagulation—a randomized trial

Abstract

OBJECTIVES Minimally invasive extracorporeal circulation (MiECC) is suggested to have favourable impact on blood loss compared to conventional extracorporeal circulation. We aimed to compare the impact of both systems on coagulation. METHODS Randomized trial comparing endogenous thrombin-generating potential early after elective coronary surgery employing either MiECC group (n = 30) or conventional extracorporeal circulation group (n = 30). Secondary outcomes were in vivo thrombin generation, bleeding end points and haemodilution, as well as morbidity and mortality up to 30-day follow-up. RESULTS Compared to the conventional extracorporeal circulation group, the MiECC group showed (i) a trend towards a higher early postoperative endogenous thrombin-generating potential (P = 0.06), (ii) lower intraoperative levels of thrombin–antithrombin complex and prothrombin fragment 1 + 2 (P < 0.001), (iii) less haemodilution early postoperatively as measured by haematocrit and weight gain, but without correlation to coagulation factors or bleeding end points. Moreover, half as many patients required postoperative blood transfusion in the MiECC group (17% vs 37%, P = 0.14), although postoperative blood loss did not differ between groups (P = 0.84). Thrombin–antithrombin complex levels (rs = 0.36, P = 0.005) and prothrombin fragment 1 + 2 (rs = 0.45, P < 0.001), but not early postoperative endogenous thrombin-generating potential (rs = 0.05, P = 0.72), showed significant correlation to increased transfusion requirements. The MiECC group demonstrated significantly lower levels of creatine kinase-MB, lactate dehydrogenase and free haemoglobin indicating superior myocardial protection, less tissue damage and less haemolysis, respectively. Perioperative morbidity and 30-day mortality did not differ between groups. CONCLUSIONS Conventional but not MiECC is associated with significant intraoperative thrombin generation despite full heparinization. No correlation between coagulation factors or bleeding end points with the degree of haemodilution could be ascertained. ClinicalTrials.gov identifier NCT03216720.

The impact of minimal invasive extracorporeal circulation on postoperative kidney function

“…The current study is a substudy of the "Miniaturized Extracorporeal Circulation Study" (ClinicalTrials.gov ID: NCT03216720). 12 Patients over 40 years of age referred for elective isolated CABG by the multidisciplinary Heart Team at Aarhus University Hospital, Denmark, were eligible for inclusion. Exclusion criteria were reduced ejection fraction (<40%), severe renal impairment (eGFR <30 mL/min/1.73 m 2 or dialysis), history of coagulopathy, abnormal platelet count (<100 or >450 10 9 /L), active participation in another intervention trial, and female of child-bearing potential without negative pregnancy test.…”

“…3 Perioperative management, surgery, MiECC, and CECC circuit have been described in detail previously. 12…”

Thrombin: A Pivotal Player in Hemostasis and Beyond

“…Despite heparinization, both TAT and F1 þ 2 have been found highly elevated in patients undergoing cardiopulmonary bypass, indicating ongoing thrombin formation during surgery. [144][145][146] Ex vivo thrombin generation capacity has further been found decreased in the postoperative phase, indicated by prolonged lag time and low ETP and peak thrombin formation compared with healthy individuals. 147 This indicates excessive prothrombin consumption and decreased hemostatic capacity, which may enhance bleeding risk in the early postoperative phase.…”

“…[149][150][151] Our group found that high intraoperative TAT and F1 þ 2, but not decreased ETP, was associated with a higher number of blood transfusions. 144 Thus, assessment of thrombin generation Table 1 Markers of thrombin generation and thromboembolic risk in various clinical conditions…”

“…147 This indicates excessive prothrombin consumption and decreased hemostatic capacity, which may enhance bleeding risk in the early postoperative phase. The potential of in vivo and ex vivo thrombin formation markers to predict postoperative bleeding in cardiopulmonary bypass surgery has been explored by our group 144 and others. [148][149][150][151] Moorlag et al used whole blood thrombin generation assay and found that ETP below median was associated with high postoperative bleeding volume.…”