Use of ROTEM® in Pediatric Cardiac Surgical Patients

Cardiac surgery requiring use of a heart-lung machine, also known as cardiopulmonary bypass
(CPB) can induce abnormalities in blood coagulation (clotting) that lead to excessive blood
loss during and after operation. While of significant concern in adults, this problem takes
on even greater importance in children due to the simple fact that they have a smaller blood
volume. It is well known that if a child has previously undergone a heart operation, they
are at increased risk of bleeding should more cardiac surgery be required ("reoperation").
The processes regulating blood coagulation are extraordinarily complex, and little is known
about the exact mechanisms that contribute to the increased bleeding associated with cardiac
reoperation in children. Rotational thromboelastometry (ROTEM®) is a technology that can
provide, at the bedside, detailed information about coagulation abnormalities. While not
currently approved for general use in the United States, in Europe ROTEM® has been used to
guide administration of the blood products in surgery based upon determination of specific
coagulation abnormalities. Importantly, there is now evidence that guidelines for
transfusion therapy based on ROTEM® reduce transfusion requirements thus decreasing patient
exposure to blood products. Whether the use of ROTEM® has potential benefit for pediatric
cardiac surgical patients has not been studied. Accordingly, the present study was designed
to provide preliminary data comparing coagulation profiles between children undergoing
cardiac reoperation to those having primary procedure.

The investigators hypothesize that ROTEM® analysis will detect a pattern of impaired
coagulation in children undergoing reoperation. The overall objective of the four assays of
ROTEM® analysis therefore, is to provide information that can be used to devise a rational
transfusion protocol for pediatric cardiac surgical subjects.