Activation of Blood Coagulation After Aneurysmal Subarachnoid Hemorrhage: A Prospective Observational Trial of Rotational Thromboelastometry

Abstract

Objectives: Aneurysmal subarachnoid haemorrhage (aSAH) is reported to actuate blood coagulation. Rotational thromboelastometry (ROTEM) is a dynamic haemostatic test that can differentiate various coagulation abnormalities, for example, increased coagulation activity can be detected as a wider amplitude of tracing (maximal clot firmness [MCF]). Previously, ROTEM has not been used to evaluate coagulation changes after aSAH. The aim of this prospective, observational study was to evaluate the ongoing coagulation process in patients with aSAH by comparing their ROTEM assay results to the control values obtained from patients undergoing clipping of non-ruptured aneurysms. Methods: ROTEM analyses were performed at 12, 24, 48, and 72 hours after onset of aSAH and were compared with preoperative analyses of the control group. In total, 17 aSAH treated in the intensive care unit and 16 control patients were enrolled. Results: At 72 hours, EXTEM-MCF was significantly higher in aSAH patients compared with the baseline value of the control group (68.0 mm [interquartile range, {IQR} 66.0-71.0 mm] vs. 64.5 mm [IQR, 59.5-66.8 mm]; P = 0.024). This was mainly due to increased fibrin formation and fibrin polymerisation as the same comparison in FIBTEM-MCF analysis yielded similar results (23.0 mm [IQR, 19.0-25.0 mm] vs. 15.4 mm [IQR, 12.5-17.8 mm], respectively; P=0.001). Conclusions: Blood coagulation is activated at 72 hours after onset of aSAH, which can be detected by ROTEM EXTEM-MCF analysis. At the same time, FIBTEM-MCF was elevated, implying that relative contribution of fibrin formation and fibrin polymerisation are essential.

Laboratory assessments of therapeutic platelet inhibition in endovascular neurosurgery: complication prediction using the VerifyNow P2Y12 assay and thromboelastography with platelet mapping

“…The role of TEG in general in neurosurgery-with or without PM-remains unproven, but promising reports are proliferating. 11,12,17,18,22,27,32 Conclusions TEG-PM is ineffective in predicting complications in endovascular neurosurgery patients. Its use for this indication is questionable, although further study is necessary in this regard.…”

Hemostasis and Fibrinolysis following Aneurysmal Subarachnoid Hemorrhage: A Systematic Review on Additional Knowledge from Dynamic Assays and Potential Treatment Targets

“…[53][54][55]57,66,67 However, while four studies found hypercoagulation on admission, 53,54,57,66 two studies did not reveal hypercoagulation until 72 hours after ictus. 55,67 Between studies, clot initiation, amplifica-tion, and strength were changed to different degrees. While the low tissue factor ROTEM assay revealed changes toward hypercoagulation in all phases of coagulation on admission, 53 the commercially available ROTEM assay revealed only increased clot strength 54 ; however, this was revealed in both ExTEM and FibTEM maximum clot firmness.…”

“…Overall, mean platelet count on admission was within reference range or equivalent to the control group in all studies measuring this. 30,31,36,[49][50][51][52][53][54][55][56] In one study, the platelet count was higher in aSAH patients than in the control group, but a reference range was not provided. 57 When measured over days following aSAH, platelet count tended to decrease with a minimum between days 4 and 14.…”

“…Studies employing dynamic assays are presented in ►Tables 2 (n ¼ 11), [49][50][51][52][58][59][60][61]63,68,69 3 (n ¼ 7), [53][54][55]57,66,67,70 and 4 (n ¼ 5), 56,62,64,65,71 according to their primary aim. ►Table 2 contains studies evaluating platelet function applying either platelet aggregation analyses or viscoelastic assays.…”

“…Three of the studies partly shared the same cohort. 53,54,65 Three studies used ROTEM [53][54][55] and five studies used TEG. 56,57,66,67,70 Assays vary between studies, as both commercial ROTEM 54,55 and TEG assays 57,67,70 were applied, as well as TEG6 66 and a low tissue factor ROTEM assay.…”