Coagulation Day 2010: an Austrian survey on the routine of thromboprophylaxis in intensive care.

PURPOSE: Venous thromboembolism (VTE) is a common but often overlooked life-threatening complication of critical illness. The aim of this cross-sectional survey was to assess current practice of thromboprophylaxis as well as adherence to international guidelines. METHODS: After ethics committee approval, all intensive care units in Austrian hospitals treating adult patients were invited to participate in this web-based survey. Anonymized data on each patient treated at the participating intensive care units on Coagulation Day 2010 were collected using an electronic case report form. Risk assessment, choice and monitoring of anticoagulants, means of mechanical prophylaxis, and demographic data were recorded. RESULTS: Data from 325 critically ill patients were collected. Patients had a median of four risk factors for thrombosis and 6 % suffered from VTE. Of the 325 patients, 80 % received low molecular weight heparins subcutaneously, 10 % received unfractionated heparin intravenously, 1 % received alternative anticoagulants and 9 % received no pharmacological prophylaxis. Mechanical prophylaxis was used in 49 % with a predominant use of graduated compression stockings. In 39 % a combination of pharmacological and mechanical prophylaxis was applied and 5 % received no prophylaxis at all. Overall guideline adherence was 40 % on Coagulation Day 2010. CONCLUSION: Current practice of thromboprophylaxis is predominantly based on the administration of low molecular weight heparins prescribed at rather arbitrary doses without a discernible relationship to drug monitoring, thromboembolic risk factors, vasopressor use or fluid balance. The use of mechanical prophylaxis, evaluation of risk scores and overall guideline adherence must be further encouraged by education, training and communication.

Acquired type 2A von Willebrand syndrome caused by aortic valve disease corrects during valve surgery.

BACKGROUND: Aortic valve (AV) defects can destroy high molecular weight multimers (HMWM) of von Willebrand factor (VWF), leading to acquired von Willebrand syndrome (aVWS) type IIA. This syndrome is considered a cause for increased perioperative bleeding in AV surgery. If diagnosed before operation, administration of VWF/FVIII concentrates is recommended. However, there is currently no evidence that the VWF HMWM defect persists during surgery long enough to require haemostatic therapy. We hypothesized that the preoperative VWF HMWM defect corrects already during cardiopulmonary bypass (CPB) before any haemostatic therapy. METHODS: This prospective observational study enrolled 17 patients undergoing AV surgery, either isolated or associated with mitral valve or aorta surgery, and also 10 patients undergoing coronary artery bypass surgery (CABG) for comparison. VWF HMWM, VWF antigen (VWF:Ag) concentration, and collagen-binding capacity (VWF:CB) were measured before operation, directly after weaning from CPB, and on the first postoperative day. RESULTS: In 12 of the 17 subjects undergoing AV surgery (71%), VWF HMWM were abnormally absent before operation. At the end of CPB, VWF HMWM were normal in 15 of AV subjects (88%), and was normal in 16 subjects on the first postoperative day. VWF:Ag and VWF:CB were within or above the normal range at all three times. Two out of 10 subjects undergoing CABG (20%) had preoperative deficits of VWF HMWM that normalized after operation. CONCLUSIONS: Preoperative VWF HMWM defects corrected at the end of CPB in the absence of haemostatic therapy in most patients undergoing AV surgery. Diffuse bleeding occurring after CPB is unlikely to be related to persisting type 2A von Willebrand syndrome; other causes of coagulopathy should be suspected. Administration of VWF/FVIII concentrates appears unnecessary in this setting.

Recovery of fibrinogen after administration of fibrinogen concentrate to patients with severe bleeding after cardiopulmonary bypass surgery.

BACKGROUND: Normalization of plasma fibrinogen levels may be associated with satisfactory haemostasis and reduced bleeding. The aim of this retrospective study was to assess fibrinogen recovery parameters after administration of fibrinogen concentrate (Haemocomplettan P) to patients with diffuse bleeding in cardiovascular surgery. Data on transfusion and patient outcomes were also collected. METHODS: Patient characteristic and clinical data were obtained from patient records. RESULTS: of the thromboelastometry (FIBTEM)and of the standard coagulation tests, including plasma fibrinogen level, measured before surgery, before and after haemostatic therapy, and on the following day, were retrieved from laboratory records. Results Thirty-nine patients receiving fibrinogen concentrate for diffuse bleeding requiring haemostatic therapy after cardiopulmonary bypass were identified. The mean fibrinogen concentrate dose administered was 6.5 g. The mean fibrinogen level increased from 1.9 to 3.6 g litre(-1) (mean increment of 0.28 g litre(-1) per gram of concentrate administered); maximum clot firmness increased from 10 to 21 mm. The mean fibrinogen increase was 2.29 (sd 0.7) mg dl(-1) per mg kg(-1) bodyweight of concentrate administered. Thirty-five patients received no transfusion of fresh-frozen plasma (FFP) or platelet concentrate after receiving fibrinogen concentrate; the remaining four patients received platelet concentrate intraoperatively. Eleven patients received platelets, FFP, or both during the first postoperative day. No venous thromboses, arterial ischaemic events, or deaths were registered during hospitalization. CONCLUSIONS: In this retrospective study, fibrinogen concentrate was effective in increasing plasma fibrinogen level, and contributed to the correction of bleeding after cardiovascular surgery.