When should the Rotem (Rotational Thromboelastometry) test be used in clinical settings?

ROTEM Test: Clinical Indications and Applications

ROTEM should be used primarily in patients with major bleeding and suspected coagulopathy to guide targeted blood product transfusion, particularly in trauma, cardiac surgery, obstetric hemorrhage, and critically ill patients where rapid coagulation assessment can reduce unnecessary transfusions and improve outcomes. 1

Primary Clinical Settings for ROTEM Use

Major Hemorrhage and Trauma

• ROTEM-guided transfusions in trauma patients are conditionally recommended over traditional coagulation parameters, as they are associated with reduced mortality and fewer blood product transfusions. 2
• Use ROTEM in patients with major bleeding where clinical features (heart rate, cold peripheries, prolonged capillary refill time) are often insensitive for detecting coagulopathy. 1
• ROTEM provides rapid turnaround time and information on all phases of coagulation, which is critical when managing trauma-induced coagulopathy. 1
• Specific ROTEM parameters (EXTEM and FIBTEM clot amplitude at 5 and 10 minutes) consistently diagnose coagulopathy, predict massive transfusion requirements, and predict mortality in trauma patients. 3

Cardiac and Vascular Surgery

• ROTEM has well-established utility in cardiac surgery for reducing perioperative transfusion requirements. 1
• The activated clotting time (ACT) should be used routinely whenever heparin is administered, particularly in cardiac and vascular surgery. 1

Obstetric Hemorrhage

• The most robust evidence for ROTEM use in obstetrics is for guiding transfusion therapy in postpartum hemorrhage (PPH), where it can identify patients at risk for severe hemorrhage. 1
• ROTEM may best serve a role in clinically guiding transfusion therapy in obstetrics, though evidence is still evolving. 1

Specific ROTEM Parameters and Transfusion Thresholds

Fibrinogen Replacement

• Administer cryoprecipitate (2 pools) or fibrinogen concentrate when FIBTEM CA5 < 10 mm. 1
• Target fibrinogen level of at least 1.5-2.0 g/L in bleeding patients, as fibrinogen is often the first coagulation factor to reach critically low levels. 4
• FDA labeling supports using ROTEM FIBTEM A10 ≤ 10 mm as a threshold for additional fibrinogen dosing in acquired fibrinogen deficiency. 5

Platelet Transfusion

• Administer 1 pool of platelets when EXTEM CA5 - FIBTEM CA5 < 30 mm. 1
• Maintain platelet count >50,000/mm³ for life-threatening hemorrhage, with higher targets for neurosurgery or traumatic brain injury. 4

Fresh Frozen Plasma

• Administer 4 units FFP when EXTEM CA5 > 40 mm plus EXTEM CT > 80 s. 1
• Target PT/aPTT < 1.5 times normal control. 4

Tranexamic Acid

• Consider additional 1 g tranexamic acid when EXTEM LI30 < 85%. 1
• Do not withhold tranexamic acid therapy while waiting for ROTEM results, as ROTEM is less sensitive to measuring fibrinolytic activation in trauma. 1

Important Limitations and Pitfalls

Technical Considerations

• ROTEM requires a trained user to be present for accurate interpretation. 1
• Poor standardization exists apart from manufacturers' reported reference ranges, and there is lack of universal algorithms across different specialties. 1
• ROTEM is recognized to be less sensitive to measuring fibrinolytic activation in trauma and should not be used to withhold administration of tranexamic acid. 1

Diagnostic Accuracy Concerns

• An isolated EXTEM clotting time > 80 seconds may not reflect clinically significant coagulopathy, as coagulation factor levels in this group are similar to patients with normal ROTEM and have no impact on mortality. 6
• ROTEM may not be sensitive enough to detect subtle differences in coagulability, particularly in detecting residual anticoagulant activity in patients on DOACs. 1
• Traditional coagulation tests (PT, aPTT) may not correlate well with clinical bleeding or ROTEM parameters. 7, 4

Clinical Context

• Do not delay treatment while waiting for ROTEM results in cases of severe bleeding. 7, 4
• ROTEM should augment, not replace, empiric major hemorrhage protocol therapy. 1
• Increased fibrinolysis can be present when lysis index at 30 minutes is normal but EXTEM and FIBTEM clot amplitude at 5 minutes is decreased. 6

Monitoring During Treatment

• Continue monitoring ROTEM parameters to guide ongoing treatment and assess response to therapy. 4
• Serial measurements of plasma fibrinogen levels or viscoelastic properties should be performed during treatment. 5
• In liver disease, ROTEM may provide more valuable information than standard coagulation tests. 4

Evidence Quality Considerations

• While ROTEM shows promise in reducing transfusions and improving outcomes, the evidence base outside cardiac surgery remains limited, with most studies being observational rather than randomized controlled trials. 2, 8, 9
• The only RCT providing strong evidence for ROTEM use in obstetrics is for guiding therapy in PPH. 1
• Newer automated, cartridge-based versions (ROTEM sigma) may expand point-of-care capabilities. 1