PB0242 - Monitoring of hemostasis and heparinization of neonates undergoing cardiac surgery (CS) using viscoelastic testing (VT) and standard laboratory test (SLT).

Sunday, July 10, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Marina S. Lopez, Specialist

Biochemist
Hematology and hemostasis division, Central Laboratory,Hospital Italiano de Buenos Aires, Argentina.
Ciudad Autonoma de buenos aires, Ciudad Autonoma de Buenos Aires, Argentina

Co-Author(s)

PR

Pablo I. Rossi

Anesthesiologist doctor
Anesthesia department, Hospital Italiano de Buenos Aires, Argentina.
Ciudad Autónoma de Buenos Aires, Ciudad Autonoma de Buenos Aires, Argentina
TV

Tomas J. Vainstein

Anesthesiologist doctor
Anesthesia department, Hospital Italiano de Buenos Aires, Argentina.
Ciudad Autónoma de Buenos Aires, Ciudad Autonoma de Buenos Aires, Argentina
BD

Brenda G. Diaz

Laboratory technician
Hematology and hemostasis division, Central Laboratory,Hospital Italiano de Buenos Aires, Argentina.
Ciudad Autónoma de Buenos Aires, Ciudad Autonoma de Buenos Aires, Argentina
LB

Luis H. Barrera

Director Central Laboratory
Hospital Italiano de Buenos Aires
CIUDAD AUTONOMA DE BUENOS AIRES, Buenos Aires, Argentina
MM

Marta E. Martinuzzo

Biochemist Supervisor Hemostasis Central Laboratory
Hospital Italiano de Buenos Aires
CIUDAD AUTONOMA DE BUENOS AIRES, Buenos Aires, Argentina

Background: Adequate management of heparinization and hemostasis in neonates undergoing CS with cardiopulmonary bypass is challenging.

Aims: To track the effect of heparin and CS in neonates weighing < 5 kg using VT and SLT.

Methods: Neonates weighing < 5kg undergoing CS were included. Samples were obtained at the start of surgery (Basal), before separation from bypass (Bypass) and after heparin reversal (Postprotamine).
VT performed by ROTEM delta (Instrumentation Laboratory , IL). SLT: PT% activity (PT%), APTT, thrombin time (TT), antithrombin (AT) and anti-factor Xa activity (AntiXa) by IL reagents in ACL TOP coagulometer.
HemoCell CXH800 (Beckman Coulter) for PLT.
Cumulative 12 hours chest tube drainage (CTD) was assessed for postsurgical bleeding.

Results: 32 patients were included. Median (IRQ) age was 19 days (6-25), median weight was 3380 gr (3082-3785). Bypass samples showed significantly prolonged EXTEM, INTEM and FIBTEM CFT and CT, as well as lower amplitude for A5, A10 and MCF when compared to Basal and Postprotamine.
PT% decreased, and APTT increased in Postprotamine compared to Basal.
PLT were lowest during bypass. Median basal AT was 0.56 IU/mL.
AntiXa median (IQR) was 5.3 (4.1-6.9) during Bypass. Postprotamine AntiXa was 0.1 (0.03-0.33), 9/32 patients with > 0.2 U/mL.
AntiXa correlated with EXTEM-CT and ACT during bypass, and with TT in Postprotamine. Postprotamine ACT correlated with PT, APTT, INTEM and HEPTEM CTs, and HEPTEM/INTEM CT ratio (table 1). Postprotamine AntiXa and ACT did not correlate.
HemoCell CXH800 (Beckman Coulter) for PLT.
Median CTD was 50 mL (28-91). CTD correlated with Postprotamine AntiXa and TT, and with total heparin dose administered (table 2).

Conclusion(s): ROTEM results were most affected during bypass, when hemodilution and consumption of procoagulant factors, fibrinogen and platelets are expected to occur.
AntiXa was the only test that tracked heparinization at all stages of surgery. Residual heparin measured by AntiXa correlated with postoperative bleeding.