Hematologic Changes Clinical Trial
Official title:
The Effect of Preoperative Blood Harvesting and Its Re-administration at the End of Cardio-pulmonary Bypass on the Coagulation Profile in the Pediatric Population Undergoing Open Heart Surgery.
Blood transfusions after pediatric heart surgery is a relatively common practice occurring
in up to 46% of patients, however its use has been associated with increased morbidity. In
the pediatric population undergoing heart surgery transfusion of homologous blood is usually
required due to the mismatch between the priming volume of the cardiopulmonary bypass
circuit and the patients own blood volume. Several strategies have been proposed in order to
minimize the use of blood products. The effect of pre-operative harvest of fresh whole blood
in the adult population has shown a beneficial platelet protective effect, however concerns
have been risen that the amount of volume needed in order to sequester a significant amount
of platelets would be prohibit ally high in a cardiac surgical patient. Fresh blood
harvesting has not been evaluated in the pediatric population.
The purpose of the present study would be to evaluate the safety and efficacy of
pre-operative blood harvesting in the pediatric population undergoing open heart surgery.
Fresh whole blood will be harvested from the patient prior to the initiation of
cardiopulmonary bypass and will be returned to the patient after the discontinuation of CPB
prior to the administration of prominent. Parameters that will be evaluated will include,
patient characteristic, operative and post-operative parameters, coagulation profiles and
the use of postoperative blood products.
All pediatric patients undergoing open heart surgery at our institution will be randomized
based on the last digit of their identification number (even or odd numbers) to undergo
pre-operative whole blood harvesting (PBH). Informed consent will be obtained from the
parents at the time of surgical informed consent acquisition.
After scrubbing and draping of the patient the first set of blood samples will be obtained
for baseline.
Circuit priming will be performed using plasmalyte , and the prime will be adjusted to have
a calculated bypass hematologic 27%, taking into consideration the amount of blood
harvested.
Once the patient is connected to the CPB circuit, harvested blood will be taken from the
venous line before its passage through the oxygenator, while crystalloids from the circuit
will be infused through the arterial line in order to maintain adequate blood pressure. Once
the amount of 15cc/kg of blood is harvested, CPB will be initiated and the operation will be
carried out in the usual manner. Blood will be kept at room temperature (18°C), gently
stirred (not shaken).
At the end of the operation, veno-venous ultrafiltration will be performed, targeting a
duration of 10 minutes. The harvested blood will be administered at the end of
ultrafiltration in conjunction to the administration of protamine. Blood samples will be
obtained at various time points. Complete blood count, coagulation profile (PT/PTT), and
platelet function tests will be performed. Pre-operative and operative characteristics will
be recorded .
In the intensive care unit, the patient will be continuously followed until his discharge
from the hospital and post-operative parameters will be recorded. Blood and blood product
administration will be based on our ICU protocol and at the discretion of the attending
physician. Generally, blood will be administered to single ventricle patients if their
hemoglobin levels will be below 12 mg%, while in the 2 ventricle patients a threshold of
9mg% will be set. Administration of blood products will be performed if there will be signs
of clinical bleeding with overt signs of coagulopathy (INR > 2, fibrinogen < 100, platelets
< 50,000).
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Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic