INTRODUCTION
Acute type A aortic dissection (ATAAD) is a lethal condition requiring emergent aortic surgery. The procedure is challenging and associated with high rates of peri-operative bleeding and blood product transfusions. Mortality is high with rates ranging from 16-18% after surgery in large registries 1-3. A significant cause of the high mortality and morbidity is peri-operative bleeding4. The impairment of the coagulation system is caused by the contact of blood with the non-endothelialized walls of the false lumen, but other triggers also have been suggested5-7. Surgery for acute type A aortic dissection is conducted using a cardiopulmonary bypass circuit and usually a deep hypothermic state, both of which further increase the coagulopathy.
Transfusion strategy in major aortic surgery may either be reactive, with the administration of blood products in response to the development of a clinical coagulopathy, or pre-emptive, based on the administration of blood products to prevent a clinically detectable coagulopathy. Both approaches lead to a significant use of blood products. A recent review of bleeding management in vascular surgery concluded that hemostasis should be monitored, and goal directed8. This calls for alternative bleeding management, and the adoption of a transfusion algorithm guided by rotational thromboelastometry (ROTEM) could be an option.
At many centers, management of perioperative bleeding is carried out according to rotational ROTEM-guided protocol for transfusion of blood products and procoagulants, reducing the need for transfusions and decreasing the risk of bleeding after cardiac surgery9-12.
A prospective study by Ogawa et al. 13 compared values obtained using standard laboratory coagulation tests (PT(INR), APTT and fibrinogen) with ROTEM CT and MCF values for the parameters INTEM, EXTEM, HEPTEM, and FIBTEM in adult patients undergoing cardiac surgery and demonstrated that some ROTEM measurements could act as surrogates for standard coagulation tests. However, although reference ROTEM values in patients undergoing elective and non-complex cardiac surgery have been described 14-16, similar data are lacking in the acute and complex setting. Furthermore, few studies have investigated the dynamics of the key components of the coagulation system visualized by ROTEM in association with the complex coagulopathic setting of ATAAD surgery. It is therefore unclear whether the ROTEM-guided treatment algorithm utilized in routine surgery also may be used when performing ATAAD repair.
To assess the performance of ROTEM during surgery for ATAAD, we reviewed ROTEM in surgically treated patients with ATAAD compared to a control group undergoing elective aortic surgery.