Effective haemostasis in case of haemorrhage requires fibrinogen activation to form a haemostatic fibrin clot and stabilisation of this clot by crosslinking with coagulation factor XIII. In case of a blood loss compensated with intravenous administration of infusion solutions, both procoagulant factors, fibrinogen and factor XIII, decrease due to consecutive haemodilution.
In their prospective observational study in 290 patients undergoing elective craniotomy, Adelmann and coworkers investigated the association between the plasma concentration/activity of fibrinogen and cogulation factor XIII and the presence or absence of postoperative bleeding requiring surgical revision.
While postoperative fibrinogen concentration was significantly lower in bleeding patients (170 ± 35 vs. 237 ± 86 mg/dL; P = 0.03), a comparable signal in the postoperative factor XIII activity could not be detected (65 ± 8 vs. 72 ± 17%; P = 0.35). Other parameters investigated indicating the postoperative coagulation status, i.e. prothrombin time, activated partial thromboplastin time and platelet count, were not different between bleeding and non-bleeding patients.
The risk of bleeding was about 10-fold increased if the postoperative fibrinogen concentration was lower than 200 mg/dL, emphasizing correction of postoperative fibrinogen level to values >200 mg/dL in intracranial surgery in order to avoid postoperative haemorrhage.
– Oliver Habler
Discuss this article on the Nataonline forum