Changes in fibrinolysis in the intensive care patient.

Critically ill patients have been described as having blood coagulation abnormalities that predispose to bleeding and thrombosis. We have studied plasminogen activators, alpha 2-antiplasmin, X-oligomers fibrin fragments, fibronectin, antithrombin III, fibrinogen, platelets, kaolin-cephalin clotting time and prothrombin time on admission to the intensive care unit and sequentially after 24 and 48 hours in 39 adult patients: ARDS (n = 6), trauma (n = 12), sepsis (n = 8) and a miscellanea (n = 13). A decrease in plasminogen activators associated with an increase in X-oligomers, the earliest form of cross linked fibrin degradation products, indicate that fibrin deposition and the consumption of components of fibrinolysis is a widespread condition in the ICU patients. Low fibronectin levels were related to prognosis. These findings suggest that critically ill patients must be evaluated in respect to fibrinolysis and supported when necessary with prophylactic treatment.

Is veno-occlusive disease a specific syndrome or the exacerbation of physiopathologic hemostatic changes in hematopoietic stem cell transplantation (HSCT)?

The objective of the present study was to analyze whether veno-occlusive disease (VOD) is based on specific findings or whether this syndrome is the exacerbation of changes in hemostatic parameters that develop following hematopoietic stem cell transplantation (HSCT). 40 patients undergoing HSCT were enrolled (6 allogeneic bone marrow transplantation and 34 peripheral stem cell rescue-2 allogeneic, 32 autologous). Measurements of hemostatic parameters (endothelial, hypercoagulability and fibrinolytic markers) were obtained prior to chemotherapy and weekly thereafter for 3 weeks. The incidence of VOD was 15%. HSCT showed a state of moderate hypercoagulability (increase of thrombin-antithrombin complex and fibrinogen, and decrease of Factor VII, Protein C, and antithrombin-III), probably as a consequence of marked endothelial damage (increase of von Willebrand Factor and tissue plasminogen activator). All these alterations create a potentially prothrombotic state, more pronounced in VOD. The decreasing incidence of VOD and the moderate disease in all patients suggest that increasing improvements in transplant strategies have reduced the risk and severity of a syndrome that at the beginning of the transplantation era was a leading cause of morbidity/mortality.

[Von Willebrand disease: characteristics and response to desmopressin. Study of 103 cases]. / Enfermedad de Von Willebrand: características y respuesta a desmopresina. Estudio de 103 casos.

BACKGROUND: To describe the main characteristics and response to desmopressin infusion in 103 patients suffering from von Willebrand disease (vWD). PATIENTS AND METHODS: The criteria for diagnosis were (except for type 2N) the coexistence of von Willebrand factor ristocetin cofactor (vWF:RCo) activity < 50 U/dl with bleeding disease or one of the following data: von Willebrand factor antigen (vWF:Ag) activity < 50 U/dl, factor VIII (FVIII) activity < 50 U/dl or the existence of a increased bleeding time (BT). Multimeric studies of vWF were performed in 51 cases and ristocetin induced platelet aggregation (RIPA) was also performed. RESULTS: Spontaneous bleeding was found in 36 patients, while in 18 cases the diagnosis was done after surgical bleeding. Thirteen patients (6 presenting with mild bleeding) were studied for abnormalities in the routine preanestesic tests. Other 22 patients were diagnosed with vWD by familial studies. There were 3 patients with type 2B, 1 case with type 2N and other patient with type 3. BT was found increased in 26 out of 58 patients. The activities of vWF:CoR and vWF:Ag were 38.4 (9.4) U/dl and 45.8 (23.2) U/dl, respectively, while the activity of FVIII was 49.9 (20.8) U/dl. Prophylactic DDAVP (desmopressin) was infused in 32 patients. After 1 h, basal activities of vWF:CoR and vWF:Ag were increased by 3.1 (3.2) and 3.4 (3.1) times, respectively, and maintained for 3 h. FVIII activity increased 3.6 (2.3) times the basal levels decreasing after 3 h (2.9 [2.1]; p < 0.01). The BT was corrected in 8 out of ten patients. CONCLUSIONS: vWD is a major cause of surgical bleeding. Preanestesic anamnesis and coagulation tests can be useful to identify vWD. Many patients with vWD have normal BT. A failure in the response to desmopressin infusion is unusual.

[Checking oral anticoagulation in capillary blood]. / Control de la anticoagulación oral en sangre capilar.

PURPOSE: To check out the reproducibility and costs of prothrombin time (PT) determination as a control of oral anticoagulant therapy (OAT) in plasma and capillary blood. PATIENTS AND METHODS: The study was carried out in two phases: along two years, 1,700 patients with OAT were controlled, 700 of them in the hospital outpatient clinic. In 149 patients INR was simultaneously determined in both capillary and venous blood. The 700 patients receiving acenocoumarin who had been controlled in 1991 according to the conventional plasma-sample fashion, were controlled in the second year (i.e., 1992) by means of capillary blood testing, a comparison of the costs of each method and the need for anticoagulant drugs being undertaken. Venous blood PT was assessed with reagent thromboplastin (Tromborel S) in an Electra-1000 (MLA) system. An automated Trombotrack system was used for the capillary blood tests using Thrombotest as current procedure. The results were expressed as INR in both methods. The statistical evaluation of the results was carried out by means of Student's t, variance analysis, and correlation study. RESULTS: No significant differences were found in the anticoagulation intervals attained from venous or capillary blood samples. No significant differences were seen in 87 patients on whom the test was repeated in two samples drawn from a single capillary puncture. The weekly OAT doses of 30 patients along six months were analysed. The need for anticoagulant drugs was similar (17.4 vs 17.2 mg/patient/week). The mean INR in 1991 was 2.82 and the mean drug-need was 15.24 mg/week, whereas in 1992 the mean INR was 2.86 and the need for anticoagulant was 15.49 mg/week. The costs of the conventional method were 103.6 Pta, this being 70 Pta for capillary blood, which means a 32% savings. CONCLUSIONS: OAT control by means of PT performed on capillary blood must be considered a substitutive method for the venous blood assay due to its efficacy, simplicity and lower costs.