Viscoelastic haemostatic assays in the perioperative period of surgical procedures: Systematic review and meta-analysis

The aim of this study is to evaluate the safety and efficacy of Viscoelastic Haemostatic Assays (VHA) to guide transfusions in patients undergoing surgical procedures. Systematic review with meta-analysis of randomized controlled trials up until June 5, 2019. Hospitalized patients. VHAs compared to the Standard-Of-Care (SOC), which are represented by standard laboratory tests and/or clinical decisions. Primary - Risk of death, acute kidney injury, thrombotic events and reoperation for bleeding; Secondary – Risk of use of red blood cells (RBC), platelets, fresh frozen plasma (FFP), fibrinogen, factor VIIa, prothrombin complex, volume of RBC, platelets and FFP, length of hospital stay, and length of ICU stay. VHAs were associated to a statistically significant reduction in mortality (7.3% vs. 12.1%; RR = 0.64, p-value = 0.03), risk of acute kidney injury (10.5% vs. 17.6%; RR = 0.53, p-value = 0.005), volume of red blood cells (RBCs) transfused (MD = -1.63 U, p-value = 0.02), risk of platelet transfusion (23.9% vs. 27.3%; RR = 0.74, p-value = 0.006), risk of fresh frozen plasma (FFP) transfusion (RR = 0.57, p-value = 0.001), and volume of FFP transfused (MD = -0.90, p-value = 0.0003). No significant differences were observed in terms of thrombotic events, reexploration for bleeding, RBC transfusion, volume of platelets transfused, use of fibrinogen, prothrombin complex, or factor VIIa, length of hospitalization and length of ICU stay. Viscoelastic haemostatic assays are safe and efficacious for coagulation control in patients undergoing surgical procedures, therefore it should be considered for use in practice. •Allogeneic blood product transfusion has been associated with adverse outcomes.•The transfusion of blood can be driven by laboratory tests, clinical decision, and/or viscoelastic haemostatic assays.•The VHAs significantly reduced patients' risk of death, risk of acute kidney injury and tranfusions of platelets and FFP.•In only one of six previous systematic reviews, the mortality advantage with the use of VHA was demonstrated.•VHAs were considered efficacious and safe to guide transfusion in patients undergoing surgery based on final outcomes.