Viscoelastic test-based bleeding risk score reliably predicts coagulopathic bleeding in decompensated cirrhosis and ACLF patients

BACKGROUND AND AIMS

Coagulopathic bleeding risk prediction is challenging in decompensated cirrhosis (DC) by conventional assays. Viscoelastic tests (VETs) are likely to be more useful for assessing coagulation status in these patients. We investigated whether the VET (Sonoclot) parameters with fibrinogen could predict coagulopathic bleeding in these patients.

PATIENTS AND METHODS

Coagulation parameters studied in 874 patients [124 compensated cirrhosis (CC), 521 DC, and 229 acute-on-chronic liver failure (ACLF)] and 190 controls. DC patients were enrolled in derivation (n = 266) and validation (n =  255) cohorts. Sonoclot variables [activated clotting time (ACT), clot rate (CR), platelet function (PF), time to peak (TP) and peak amplitude (PA)] and fibrinogen levels were measured. Coagulopathic bleeding was recorded along with 1-year survival.

RESULTS

DC patients had prolonged ACT (p < 0.001), depressed CR (p = 0.059), reduced PF (p = 0.09), longer TP (p < 0.001) and smaller PA (p < 0.001), compared to CC and controls (p < 0.001 each). In derivation cohort, 32.3% patients had coagulopathic bleeding. Cox regression analysis of derivation cohort revealed; ACT > 190 s, PF < 1.25 and fibrinogen < 1.2 g/l could predict coagulopathic bleeding and were used to develop a bleeding risk score. In validation cohort; this score was comparable, correlated to real events, and had similar bleed free events with time. The score was also useful in predicting bleed in ACLF patients. In DC patients, 1-year mortality was higher those who bled and received transfusions.

CONCLUSION

Viscoelasticity-based bleeding risk score using ACT, PF and fibrinogen, predicts coagulopathic bleeding in DC patients and should be useful in rationalizing transfusion of blood products. We designed a viscoelastic test-based bleeding risk score which is useful in advanced liver disease to predict the coagulation-related bleeding. This figure shows the lower bleeding-free events in advanced cirrhosis with each incremental bleeding risk score.

Flow Rate and Raspberry Pi-based Paper Microfluidic Blood Coagulation Assay Device

Monitoring blood coagulation in response to an anticoagulant (heparin) and its reversal agent (protamine) is essential during and after surgery, especially with cardiopulmonary bypass (CPB). A current clinical standard is the use of activated clotting time (ACT), where the mechanical movement of a plunger through a whole blood-filled channel is monitored to evaluate the endpoint time of coagulation. As a rapid, simple, low-volume, and cost-effective alternative, we have developed a paper microfluidic assay and Raspberry Pi-based device with the aim of quantifying the extent of blood coagulation in response to varying doses of heparin and protamine. The flow rate of blood through the paper microfluidic channel is automatically monitored using Python-coded edge detection algorithm. For each set of assay, 8 μL of fresh human whole blood (untreated and undiluted) from human subjects is loaded onto each of 8 sample pads, which have been preloaded with varying amounts of heparin or protamine. Total assay time is 3-5 minutes including the time for sample loading and incubation.

The value of Sonoclot detection technology to guide the clinical medication of the perioperative anticoagulation and antiplatelet therapy in patients with acute myocardial infarction undergoing emergent PCI

The value of Sonoclot detection technology to guide the clinical medication of the perioperative anticoagulation and antiplatelet therapy in patients with acute myocardial infarction (AMI) undergoing emergent percutaneous coronary intervention (PCI) was estimated. One hundred and twenty-eight patients were randomly divided into control group and observation group with 64 cases in each group. Control group adopted routine blood coagulation indexes, including prothrombin time, activated partial thromboplastin time, fibrinogen and plasma thrombin time, platelet count and platelet aggregation turbidity analysis; observation group adopted Sonoclot detection technology, including activated clotting time, coagulation rate and platelet function. Anticoagulant therapy selected was of low molecular weight heparin calcium perioperatively, intraoperative unfractionated heparin, and clopidogrel (75 mg) combined with aspirin enteric-coated tablets (100 mg) as antiplatelet drugs. The therapy was administered in accordance with blood coagulation results. The blood coagulation time, postoperative creatine kinase isoenzyme MB, cardiac troponin I and B-type natriuretic peptide levels in the observation group are significantly lower than those in the control group (P<0.05) though the operating time and specifications of the stenting did not show any significant difference (P>0.05). The incidence of recurrent myocardial infarction, microembolism, acute and subacute thrombosis and bleeding events in the observation group are significantly lower than those in the control group (P<0.05). In the control group, there is no difference in the coagulation indexes of the patients with thrombosis events or bleeding events or no event (P>0.05). Whereas, in the observation group, there is significant difference in coagulation indexes of the patients with thrombosis events or bleeding events or no event (P<0.05). In conclusion, Sonoclot detection technology instructs emergent PCI treatment in AMI patients to shorten the detection time of blood coagulation, reduce the degree of myocardial injury, reduce the incidence of perioperative thrombosis and bleeding events. Furthermore, it has great value in guiding the clinical medication of anticoagulation and antiplatelet therapy.