Draft guidance has been published by NICE recommending two viscoelastometric testing devices – the ROTEM system (TEM International) and the TEG system (Haemonetics) – to help detect, manage and monitor blood clotting (haemostasis) in people during and after cardiac surgery.
The draft guidance also recommends that further research is carried out into the clinical benefit and cost effectiveness of using a further system – Sonoclot (Sienco Inc) – for the same indication. Further research was also recommended for the use of all three devices in the management of emergency bleeding in cases of trauma and post-partum haemorrhage.
Haemostasis is the complex process by which the blood clots in order to prevent blood loss following an injury to a blood vessel. During surgery this process can be disrupted, preventing the blood from clotting properly (coagulopathy) and resulting in excessive, sometimes lifethreatening blood loss.
Viscoelastometric point-of-care testing may be used to determine whether bleeding is a result of coagulopathy or a surgical bleed. It is mainly used in adults who are having major surgery that is associated with high blood loss, such as cardiac surgery, or in adults with emergency bleeding caused by trauma or post-partum haemorrhage. Viscoelastometric testing helps guide the clinician to select the most appropriate treatment to stop the bleeding.
Patients with serious bleeding usually require a blood transfusion and/or re-operation. Cardiac surgery uses approximately 15% of all donated blood in the UK, and the proportion of patients requiring re-operation for bleeding is estimated at 2%-8% of cardiac surgery patients. The increased morbidity and mortality associated with bleeding following surgery has been shown to be related to both blood transfusion and re-operation for bleeding.
“Knowing what has caused a bleed allows treatment to be tailored to the cause of the coagulopathy rather than replacing blood with transfusion, or undertaking a further operation. For example, if thrombocytopenia, where the blood has low levels of platelets, is identified as the cause of the bleed this can be treated by platelet transfusion,” said Professor Carole Longson, NICE Health Technology Evaluation Centre director.
“Current laboratory testing is only able to identify when blood is not clotting properly, not what part of the clotting process is disrupted. The independent Diagnostics Evaluation Committee noted evidence showing that the use of viscoelastometric devices is associated with less mortality, a reduced probability of experiencing complications and less transfusion and hospitalisation costs. We are now keen to hear the views of anyone with an interest in this topic as part of this consultation.”
