Point-of-care testing in critically ill patients.

Point-of-care (POC) testing in hemostasis has experienced a significant increase in the spectrum of available tests and the number of tests performed. Short turn-around time and observation of rapid changes in test results are facilitated. The quality control process in POC testing must encompass a preanalytic (collection), analytic (measurement), and postanalytic (clinical response) phase. Erroneous interpretation of findings and difficult quality controls can outweigh the advantages of POC testing.Only a limited number of hemostatic POC tests have proven useful so far: prothrombin time POC-monitoring of oral vitamin K antagonists; activated clotting time POC-monitoring of high-dose heparin therapy; platelet function analyzer (PFA; Siemens, Marburg, Germany) closure time (CT)-detection of von Willebrand disease and severe platelet function defects; whole blood aggregometry (WBA) Multiplate (Roche Diagnostics, Rotkreuz, Switzerland), and the VerifyNow system (Accumetrics, San Diego, CA)-detection of platelet dysfunction due to antiplatelet drugs; thromboelastography-continuous observation of clot formation and fibrinolysis. The use of various agonists in WBA and thromboelastography (TEG) requires some expertise. In experienced hands the PFA CT and WBA and TEG are recommended combinations.Application of POC testing depends strictly on whether it improves medical care and patient outcome. More POC test systems are in the research pipeline, but only a few will resist the ravages of time.

Efficacy of argatroban in critically ill patients with heparin resistance: a retrospective analysis.

The patients who do not respond even to very high dosages of heparin are assumed to suffer from heparin resistance. The aim of this study was to investigate whether critically ill patients suffering from heparin resistance generally have low antithrombin III (AT) levels, and if the direct thrombin inhibitor argatroban in that case can be an effective option to achieve prophylactic anticoagulation. The study was conducted at the Department for General and Surgical Intensive Care Medicine at the University Hospital Innsbruck. We retrospectively included all patients between 2008 and 2012, who received argatroban because of poor response to high-dosage heparin prophylaxis. The period under observation lasted in total for 9 days, 2 days of anticoagulation with unfractionated heparin (UFH) and 7 days with argatroban. The primary objective was to investigate if after 7 (± 1) hours of switching to argatroban the activated partial thromboplastin time (aPTT) levels were in a prophylactic range of 45 to 55 seconds. Further objectives were to assess the AT level, side effects such as bleeding or thromboembolism, platelet count, correlation between organ function and argatroban dose as well as any need for allogeneic blood products. The study population, consisting of 5 women and 15 men with a mean (± standard deviation, SD) age of 54.6 ± 16.3 years, differed in many clinical aspects. A median (interquartile range) heparin dose of 1,000, 819 to 1,125 IU/h was administered for 2 days and failed in providing a prophylactic anticoagulation measured by the aPTT. The mean aPTT level with heparin treatment was 38.5 seconds (± 4.7) its change within that period was not significant. After switching to argatroban, the mean increase of the aPTT levels in all study patients amounted from 38.5 to 48.3 seconds (p < 0.001). The rise in aPTT clearly reaches sufficient prophylactic anticoagulant levels. The maintenance of prophylactic aPTT levels was achieved over the period of 1 week. There was neither a correlation found between low-AT levels and occurrence of heparin resistance, nor between the simplified acute physiology score II and the administered argatroban dose (r = -0.224, p = 0.342). The results of the present study indicate that argatroban is an effective alternative therapy, especially in critically ill patients, to achieve prophylactic anticoagulation when heparin resistance occurs.

Management of dabigatran-induced bleeding: expert statement.

The interdisciplinary group of experts has compiled a clinical guidance for manifest dabigatran-induced haemorrhage and envisaged invasive interventions on patients under dabigatran. It recommends an escalation of treatment measures as summarized in a pocket guide (see electronic supplementary material online and insert in the print issue).

Risk for postoperative infection after transfusion of white blood cell-filtered allogeneic or autologous blood components in orthopedic patients undergoing primary arthroplasty.

BACKGROUND: This study was designed to obtain data on the incidence of postoperative infection in patients undergoing elective orthopedic surgery and receiving white blood cell (WBC)-filtered blood components prepared according to current standards. STUDY DESIGN AND METHODS: A total of 308 consecutive orthopedic patients who opted for preoperative autologous blood donation (PAD) for primary unilateral hip and knee replacement surgery were enrolled in a prospective observational study of the incidence of postoperative infection. Patients with contraindications for PAD or with any infectious disease were not included in the study. To identify probably confounding factors, differences between patient groups were analyzed first. Identified factors, which differed between groups, and variables describing blood supply were further tested in uni- and multivariate logistic regression analysis for their independent influence on development of postoperative infection. Infection rates were compared on the basis of actual transfusion groups. RESULTS: Of the 308 study patients, 101 were not transfused, 85 received their PAD, 100 received allogeneic WBC-filtered red blood cells (RBCs), and 22 were given autologous RBCs and additionally allogeneic WBC-filtered RBCs. Overall the infection rate was 6.82 percent (21/308). Infection rates varied significantly between transfusion groups (no transfusion, 6.9%; autologous RBCs, 1.2%; allogeneic WBC-filtered RBCs, 12.0%; both transfusion types, 4.6%; p = 0.03). Allogeneic recipients showed significantly more infections compared to autologous recipients (p = 0.0053). Multivariate regression analysis confirmed transfusion of allogeneic WBC-filtered RBCs as an independent variable predicting postoperative infection (odds ratio, 23.65; confidence interval, 1.3-422.1; p = 0.01). CONCLUSION: Differences in postoperative infection rates between allogeneic and autologous recipients are still observable, although universal WBC filtration has been introduced into clinical practice.