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.