Our data suggest that during deliberate colloid administration, critically impaired fibrinogen polymerization and reduced fibrinogen concentrations might be reached earlier than expected. Therefore, maintaining fibrinogen concentrations seems essential when continuing blood loss is bridged by colloid infusion until transfusion triggers are reached, especially in patients already exhibiting borderline fibrinogen levels at baseline.
Recent changes in quality of transfusion supply, transfusion triggers as well as fluid therapy promote the development of dilutional coagulopathy. Nevertheless, up to now guidelines generally assume presence of hypocoagulability when more than one individual circulating blood volume is lost. This might be true for some patients under some conditions but is not necessarily true for every patient. Routine coagulation tests are insufficient in predicting increased bleeding and, moreover, only available after an unacceptable time delay. Therefore, the occurrence of diffuse microvascular bleeding is often used as clinical sign to start hemostatic therapy. However, such severe derangement of hemostasis might lead to the development of secondary tissue damage and frequently is unresponsive to conventional treatment. Coagulopathy occurring during extensive surgery or after polytrauma can be detected and treated early when using the ROTEM monitoring. Recent data showing a direct beneficial effect of hemostatic therapy on blood loss and final outcome are scarce. However, evidence exists that the amount of blood loss, the presence of coagulopathy, and the number of transfusions needed are associated with poor outcome in bleeding patients. Although manifold articles have been published already using thrombelastography for various indications (MEDLINE research ‘thrombelastography’, 2,022 articles), further data are needed to confirm the clinical experience that this technique is an excellent tool for safe patient management.
To explore whether intravenous administration of routinely used crystalloid or colloid solutions differently affects the coagulation system, we investigated orthopaedic patients. Since crystalloid solutions might cause hypercoagulability, we here present our results on molecular markers of coagulation and fibrinolysis. Patients undergoing knee replacement surgery randomly received isovolemic amounts of lactated Ringer's solution, 6% hydroxyethyl starch 200/0.5 or 4% modified gelatine. Arterial blood samples for determination of specific molecular markers of activated coagulation (thrombin/antithrombin complex, D-dimer, prothrombin fragment F1 + 2), fibrinolysis (plasmin/alpha 2-antiplasmin complex, tissue plasminogen activator, plasminogen activator inhibitor-1), and concentrations of coagulation factor XIII were obtained at baseline, before tourniquet release, at the end of surgery and 2 h after operation. During the observation period, thrombin/antithrombin complex increased from 4.8 to 54.7 microg/l, D-dimer increased from 0.3 to 6.0 mg/ml, prothrombin fragment F1 + 2 increased from 1.7 to 5.9 nmol/l, tissue plasminogen activator decreased from 7.3 to 6.7 ng/ml, plasminogen activator inhibitor-1 increased from 68.4 to 71.0 ng/ml, plasmin/alpha 2-antiplasmin complex increased from 281.5 to 884 microg/l and factor XIII decreased from 89.0 to 58.5%. All parameters changed significantly but without any detectable difference in the response profile between the groups receiving different intravenous fluids. During knee replacement surgery a pronounced activation of the coagulation/fibrinolytic system was observed, regardless of whether patients received crystalloid or colloid fluids. Thus, these results cannot confirm the hypothesis that crystalloid fluids per se cause hypercoagulability in vivo.
Effective treatment of severe or uncontrolled bleeding is a challenge for physicians in the operating room and intensive care unit. However, even aggressive conventional therapy may ultimately fail in some patients. Administration of recombinant activated factor VII (rFVIIa) may be the only remaining therapeutic option to stop life-threatening coagulopathic bleeding. We here describe the clinical course of 5 patients exhibiting severe continuous bleeding that could not be stopped by surgical intervention and appropriate hemostatic management but resolved after a mean dose of 90 microg/kg of rFVIIa (range, 90-120 microg/kg). Four of the five patients recovered completely, and one patient died after developing sepsis in multiorgan failure. In all patients, bleeding from wound surfaces stopped within minutes of the administration of rFVIIa. Coagulation measurements improved, and transfusion requirements declined considerably. No adverse effects associated with rFVIIa were observed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.