An audit of the diagnostic accuracy of the ROTEM®sigma for the identification of hypofibrinogenaemia in cardiac surgical patients

Abstract

The ROTEM®delta (TEM Innovations GmbH, Munich, Germany) has been used extensively worldwide for the assessment of coagulation in cardiac surgical patients. Recently, a new cartridge-based ROTEM device (ROTEM®sigma, TEM Innovations GmbH, Munich, Germany) has become available. In this paper we report an audit of the diagnostic accuracy of the ROTEM sigma for the identification of hypofibrinogenaemia in cardiac surgical patients. We hypothesised that the diagnostic accuracy of the ROTEMsigma for the identification of hypofibrinogenaemia would be in a similar range to that previously reported for the ROTEMdelta. Simultaneous blood samples for Clauss laboratory fibrinogen and ROTEMsigma FIBTEM measurements were obtained immediately after heparin reversal post-cardiopulmonary bypass in 200 adult cardiac surgical patients. The sensitivity, specificity, and positive and negative predictive values for FIBTEM A5 and A10 for the identification of hypofibrinogenaemia (Clauss fibrinogen <1.5 g/l) were calculated. The prevalence of hypofibrinogenaemia across the 200 patients was 8%. The mean sensitivity and specificity of FIBTEM A10 ≤8 mm for the identification of hypofibrinogenaemia were 0.75 and 0.90 respectively, which are in a similar range to that reported in several previous studies using the ROTEMdelta. For FIBTEM A5 ≤6 mm the values were 0.63 and 0.98 respectively. The predictive values were also in a similar range to those previously reported for the ROTEMdelta, with low false negative rates (2% for A10 ≤8 mm; 3% for A5 ≤6 mm). These findings support the use of the ROTEMsigma as an alternative to the ROTEMdelta for the identification of hypofibrinogenaemia post-cardiopulmonary bypass in cardiac surgical patients. However, further studies are required in other settings.

Viscoelastic testing: Critical appraisal of new methodologies and current literature

“…59 In 200 adult cardiac surgical patients with ROTEM sigma collected immediately after heparin reversal, the mean sensitivity and specificity of FIBTEM A10 ≤ 8 mm for the identification of hypofibrinogenemia (<150 mg/dL) were 0.75 and 0.90, respectively, which are in a similar range to that reported in several previous studies using the ROTEM delta. 60 Quantra QPlus sensitivity and specificity for hypofibrinogenemia in a combined cardiac and orthopedic surgery dataset has been reported as 0.88 and 0.88, respectively. 28 Quantra results are available more quickly than ROTEM sigma.…”

Prediction of hypofibrinogenaemia based on the starting fibrinogen and extent of haemodilution during cardiac surgery

“…We recently published two studies on the diagnostic accuracy of rotational thromboelastometry estimations of fibrinogen levels during cardiac surgery. 8,9 Both involved the measurement of fibrinogen levels intraoperatively. This provided an opportunity to assess the relationship between the proportional reductions in haemoglobin and fibrinogen during cardiac surgery using data already collected.…”

“…The eligibility criteria for the previous studies were previously published. 8,9 Likewise, the anaesthetic management of the patients and the method of blood sampling were previously described. 8,9 Blood for fibrinogen measurement was collected into a 2.7 ml citrated blood collection tube (Vacutainer; Becton Dickinson & Co., Franklin Lakes, NJ, USA).…”

“…8,9 Likewise, the anaesthetic management of the patients and the method of blood sampling were previously described. 8,9 Blood for fibrinogen measurement was collected into a 2.7 ml citrated blood collection tube (Vacutainer; Becton Dickinson & Co., Franklin Lakes, NJ, USA). Blood for haemoglobin measurement (as part of a full blood count) was collected into a 2.2 ml EDTA tube.…”

International council for standardisation in haematology recommendations on fibrinogen assays, thrombin clotting time and related tests in the investigation of bleeding disorders

“…47 The ROTEM Sigma has been used for the assessment of hypofibrinogenemia in cardiac surgery patients, with sensitivity and specificity of 75% and 90% for Fibtem A10 < 8 mm (clot firmness at 10 min) and 63% and 98% for Fibtem A5 < 6 mm (clot firmness at 5 min) compared to Clauss FBG assay. 48 Reports concerning the use of visco-elastic devices in patients with coagulopathies will be the subject of separate ICSH guidance.…”