Methods
A single institution retrospective chart review of all consecutive
patients from May 2020 to November 2021 who received PCC4 during
cardiothoracic surgery were included. IRB approval to conduct the study
was obtained. The institutional protocol is to use PCC4, a total dose of
30 units/kilogram immediately after completion of protamine
administration for cases deemed an increased risk for bleeding and/or
right heart failure including: heart transplantation, LVAD implantation,
and/or aortic surgery (e.g. ascending aortic dissection repair), and for
redo sternotomy cases (e.g. coronary artery bypass). Patients were
monitored with standard bleeding assessment protocol to guide blood
product resuscitation both intraoperatively and postoperatively with
point of care laboratory monitoring, including point of care
thromboelastogram and activated clotting time, as well as conventional
laboratory monitoring including complete blood counts, and systemic
coagulation panels (e.g. protime/international normalized ratio &
partial thromboplastin time). For the purposes of establishing the blood
transfusion threshold, products were administered based on the evidence
of bleeding affirmed with laboratory results. Blood product selection
was based on thromboelastogram in conjunction with clinical laboratory
assessment (e.g. hemoglobin, platelets, and fibrinogen). As a general
rule, packed red blood cells were considered for symptomatic need once
hemoglobin was less than 7 grams per deciliter. The same criteria were
used for fresh frozen plasma, an additional criteria being developed
enzymatic hypocoagulability or clotting factor deficiency. Platelets
were transfused for active bleeding with platelet count less than 50,000
per microliter and/or platelet dysfunction identified by
thromboelastogram. Cryoprecipitate was transfused for active bleeding
with evidence of fibrinolysis identified by thromboelastogram, as well
as fibrinogen level less than 200 milligrams per deciliter.
Patients were validated for inclusion criteria. Data collection
included: surgery type, PCC4 timing and dose, type and quantity of
blood transfusion within 72 hours postoperatively, patient demographics,
baseline anticoagulation, postoperative chest tube output, incidence of
right ventricular (RV) failure, hypersensitivity reactions, acute kidney
injury, thromboembolic events, and mortality within 45 days of
intraoperative PCC4. Primary assessment included surgery type, hourly
chest tube output, and type and quantity of blood product
administration. Secondary assessment included documentation of adverse
events such as incidence of hypersensitivity reactions, right
ventricular failure, multi-organ failure requiring renal replacement
therapy or ECMO, thromboembolic events, and mortality.