What does ROTEM (Rotational Thromboelastometry) stand for in the setting of neurosurgery?

ROTEM in Neurosurgery

ROTEM stands for Rotational Thromboelastometry, a point-of-care viscoelastic testing device used to assess whole blood coagulation in real-time during neurosurgical procedures. 1

Definition and Technical Overview

• ROTEM is a semi-automated viscoelastic machine that measures coagulation from initial clot formation through clot propagation, stabilization, and final dissolution in whole blood samples 1, 2
• The device works by placing a whole blood sample in a stationary cup with an oscillating pin that senses changes as blood progresses through various stages of clot formation and breakdown 2
• ROTEM provides real-time assessment of hemostasis at the patient's bedside, allowing for rapid decision-making during neurosurgical procedures 2, 3

Clinical Application in Neurosurgery

The World Society of Emergency Surgery strongly recommends using ROTEM as a point-of-care test to assess and optimize coagulation function during emergency neurosurgery, including ICP probe insertion, with 90% consensus agreement. 1

Specific Indications in Neurosurgical Settings

• ROTEM should be utilized during interventions for life-threatening hemorrhage combined with emergency neurosurgery 1
• The device is recommended for coagulation monitoring during ICP probe insertion procedures 1
• ROTEM-guided transfusion allows for targeted blood product management in major spine surgery, reducing unnecessary transfusions 4

Coagulation Targets During Neurosurgery

• Maintain platelet count > 50,000/mm³ for systemic hemorrhage; higher values are advisable for emergency neurosurgery including ICP probe insertion 1
• Keep PT/aPTT < 1.5 times normal control during emergency neurosurgery 1
• ROTEM provides faster results than conventional coagulation tests, which is critical in the dynamic neurosurgical setting 1

Key ROTEM Parameters Measured

• Clotting Time (CT) reflects time required for initial fibrin formation, corresponding to intrinsic or extrinsic coagulation pathways 2, 5
• Clot Formation Time (CFT) and alpha angle represent the speed at which the clot develops and strengthens 2, 5
• Maximum Clot Firmness (MCF) reflects combined contributions of platelets and fibrinogen to overall clot stability 2, 5
• Clot lysis parameters (CL30, CL60) indicate breakdown of the clot over time, detecting fibrinolysis 2, 5

Specific ROTEM Tests Used

• INTEM evaluates the intrinsic coagulation pathway using ellagic acid activation 2, 5
• EXTEM assesses the extrinsic pathway through tissue factor activation 2, 5
• FIBTEM isolates fibrinogen's contribution by inhibiting platelets with cytochalasin D 2, 5
• HEPTEM detects heparin effects on coagulation using heparinase 2, 5

Clinical Benefits in Neurosurgery

• ROTEM-guided transfusion protocols reduce blood loss and blood product use in major spine surgery 4
• Early identification of hypofibrinogenemia allows targeted cryoprecipitate administration rather than empiric FFP transfusion 4
• Point-of-care testing has shorter turnaround time compared to conventional laboratory tests, critical during ongoing hemorrhage 1
• ROTEM-guided algorithms have been shown to reduce transfusion requirements, complication rates, and healthcare costs 6

Important Limitations in Neurosurgical Context

• ROTEM cannot assess the contribution of endothelium to coagulation, so it cannot detect von Willebrand disease or disorders affecting endothelial adherence 2, 5
• Results show variability between devices and are not interchangeable between ROTEM and TEG systems 1, 2
• There are concerns about standardization with poor quality control and wide variation in results between centers 1
• The test is performed at 37°C and cannot assess effects of hypothermia on coagulation 5

Practical Implementation

• ROTEM should be integrated into evidence-based, setting-specific algorithms adapted to the neurosurgical patient population 6
• Implementation requires adequate technical and interpretation training, education, logistics, and interdisciplinary communication 6
• Local protocols must be developed based on institutional procedures and availability of hemostatic interventions 1, 6