The Sensitivity and Specificity of Rotational Thromboelastometry (ROTEM) to Detect Coagulopathy During Moderate and Severe Postpartum Hemorrhage: A Prospective Observational Study

Abstract

(Int J Obstet Anes. 2022;49:103238) Viscoelastometric hemostatic assays, such as rotational thromboelastometry (ROTEM), offer rapid, point-of-care identification of coagulopathy during postpartum hemorrhage (PPH). Previous studies investigating the use of ROTEM have used a Delta ROTEM device. This study investigates the use of the ROTEM Sigma device, identifying the sensitivity, specificity, and positive or negative predictive values in patients with PPH.

The Role of Thromboelastography during the Management of Postpartum Hemorrhage: Background, Evidence, and Practical Application

“…In uterine atony, at an estimated blood loss around 1,000 mL, only 2.2% of cases had first fibrinogen levels of ≤2 g/L and/or Fibtem A5 <12 mm, and between 1,500 and 2,500 mL PPH, the rate increased only slightly to 2.5%. 40 52 53 When bleeding was not controlled with obstetric intervention with bleeds of ≥2,500 mL, the rate of fibrinogen of <2 g/L and/or Fibtem <12 mm was 14%, which was lower than the average of 17% in the whole cohort. 49…”

“…In one study, only 1/521 woman received fibrinogen concentrate unnecessarily (with a fibrinogen 3.4 g/L) and 1 woman did not receive fibrinogen who may have benefitted from it (when her fibrinogen was 1.8 g/L). 52 This study emphasizes the importance of interpreting the results of a binary algorithm within the clinical context of the PPH.…”

“…Using a value of 17 mm for CFF amplitude (at 10 minutes) and 11 mm for Fibtem A5 to predict Clauss fibrinogen <2 g/L, the sensitivity is 0.74 to 0.76, specificity 0.97 to 0.96, a PPV of 0.57 to 0.54, and a negative predictive value (NPV) of 0.99 to 0.98. 52 72 The very high PPV of >95% for identifying a Clauss fibrinogen >2 g/L is very reassuring. The PPV of around 50% to identify a Clauss fibrinogen <2 g/L is affected by the low incidence of approximately 5% of hypofibrinogenemia in this unselected study cohort of consecutive women experiencing PPH.…”

“…In this study, if platelet transfusion had been guided by Pltem <17 mm, 12 women would have received a platelet transfusion with only three having an actual platelet number <75 × 10 9 /L. 52 The use of TEG has also been explored in three studies. 28 72 77 Kaolin MA and/or α angle was reported to have good utility for detecting platelet count <80 × 10 9 /L and/or fibrinogen ≤2 g/L in 98 women with PPH, although data for platelet count alone were not presented.…”

“…77 In addition, a simple binary cut is complicated to investigate as a significant prolongation of women with abnormal clot initiation times can normalize when fibrinogen is replaced first. 52 Fibrinogen replacement should therefore be considered as a first-line therapy during PPH guided by POC-VHA, and based on the upper limits of normal pregnant ranges, values of 75 to 100 seconds have been suggested for the EXTEM CT and 7.6 to 9 minutes for the TEG if abnormalities persist. 55 58 73…”