Retrograde Autologous Retrograde Autologous Priming of Cardiopulmonary Priming of Cardiopulmonary

Bypass Circuit Bypass Circuit

Transfusion RisksTransfusion Risks

Major risks: United StatesMajor risks: United States HIV (AIDS):HIV (AIDS): 1:100,000 - 1:250,0001:100,000 - 1:250,000 Hepatitis B:Hepatitis B: 1: 200,0001: 200,000 Hepatitis C:Hepatitis C: 1: 2,000 - 1:8,0001: 2,000 - 1:8,000 Acute hemolytic Acute hemolytic

reaction:reaction: 1: 33,0001: 33,0001: 800,000 = fatal1: 800,000 = fatal

Allergic reaction:Allergic reaction: 1: 20,0001: 20,000

Transfusion RisksTransfusion Risks

Minor risks: United StatesMinor risks: United States Febrile reactionFebrile reaction Graft vs host diseaseGraft vs host disease 1: 1,000,0001: 1,000,000 Delayed hemolytic reactionDelayed hemolytic reaction 1: 10,0001: 10,000 AlloimmunizationAlloimmunization Immunosuppression (??)Immunosuppression (??)

Transfusion RisksTransfusion Risks

Religious Risks: GlobalReligious Risks: Global

5,000,000 - 7,000,000 people worldwide are of 5,000,000 - 7,000,000 people worldwide are of religions that choose to avoid blood religions that choose to avoid blood transfusions, even at the risk of deathtransfusions, even at the risk of death

> 1,000,000 Jehovah’s Witnesses in the U.S.> 1,000,000 Jehovah’s Witnesses in the U.S.

Transfusion Rates in USATransfusion Rates in USA

Red blood cells:Red blood cells: 2.3 units / patient2.3 units / patient

Platelets / FFP / Cryo:Platelets / FFP / Cryo: 2.9 units / patient2.9 units / patient

Total exposure:Total exposure: 5.2 units / patient5.2 units / patient

Transfusion Costs in USATransfusion Costs in USA

400,000 cardiac surgery procedures / year400,000 cardiac surgery procedures / year

Red blood cells = 2.3 U / patient X $220.00 Red blood cells = 2.3 U / patient X $220.00 X 400,000 X 400,000 == $202,400,000$202,400,000

Platelets / FFP / Cryo = 2.9 U / patient X $75.00Platelets / FFP / Cryo = 2.9 U / patient X $75.00X 400,000X 400,000 == $87,000,000$87,000,000

Total costs / yearTotal costs / year == ~ $300,000,000~ $300,000,000

Retrograde Autologous Prime Retrograde Autologous Prime (RAP)(RAP)

What is RAP: Retrograde Autologous What is RAP: Retrograde Autologous PrimePrime

RAP involves displacing the pump prime RAP involves displacing the pump prime with the patients own blood, prior to CPBwith the patients own blood, prior to CPB

This causes less hemodilution and, This causes less hemodilution and, therefore, a higher hematocrit on bypass therefore, a higher hematocrit on bypass

Benefits of RAPBenefits of RAP

Reduced hemodilutionReduced hemodilution More physiological viscosity = better BP managementMore physiological viscosity = better BP management Higher HCT = better O2 transfer / less RBC’s usedHigher HCT = better O2 transfer / less RBC’s used Higher circulating plasma proteins = less edemaHigher circulating plasma proteins = less edema Higher circulating clotting factors = higher platelet counts Higher circulating clotting factors = higher platelet counts

and fibrinogen = less bleeding = less platelets usedand fibrinogen = less bleeding = less platelets used Higher circulating vasoregulating hormones =better Higher circulating vasoregulating hormones =better

blood pressure managementblood pressure management

Retrograde Autologous PrimeRetrograde Autologous Prime

How is RAP performed: 2 StagesHow is RAP performed: 2 Stages Stage 1: slow withdrawl of blood from aortaStage 1: slow withdrawl of blood from aorta Clamp arterial line between oxygenator and filterClamp arterial line between oxygenator and filter Open clamp distal to arterial filter, open filter purgeOpen clamp distal to arterial filter, open filter purge Aorta → arterial line → filter → purge line → reservoirAorta → arterial line → filter → purge line → reservoir Turn arterial pump slowly to move extra prime from Turn arterial pump slowly to move extra prime from

reservoir to an empty bag connected to recirc linereservoir to an empty bag connected to recirc line May need phenylephrine or levophed dripMay need phenylephrine or levophed drip

Retrograde Autologous PrimeRetrograde Autologous Prime Stage 2: removal of prime in venous lineStage 2: removal of prime in venous line Open venous line slowly by controlling with hand clampOpen venous line slowly by controlling with hand clamp Allow venous blood to push clear prime into reservoirAllow venous blood to push clear prime into reservoir Clamp venous line before venous blood reaches inlet of Clamp venous line before venous blood reaches inlet of

reservoirreservoir Turn arterial pump slowly to move extra prime from Turn arterial pump slowly to move extra prime from

reservoir to collection bag connected to recirc linereservoir to collection bag connected to recirc line

Retrograde Autologous PrimeRetrograde Autologous Prime Stage 2: removal of prime in venous line (cont’d)Stage 2: removal of prime in venous line (cont’d)

Now slowly fill reservoir with blood from venous lineNow slowly fill reservoir with blood from venous line Turn arterial pump slowly to chase remaining clear prime Turn arterial pump slowly to chase remaining clear prime

until blood reaches the collection baguntil blood reaches the collection bag

Retrograde Autologous PrimeRetrograde Autologous Prime

Hang removed prime, and use during CPB if Hang removed prime, and use during CPB if neededneeded

Keep in mind, that vasopressors may need to be Keep in mind, that vasopressors may need to be administered at the start of CPB, to stabilize the administered at the start of CPB, to stabilize the patientpatient

Vasopressors commonly used via drip, and Vasopressors commonly used via drip, and include phenylephrine or leveophedinclude phenylephrine or leveophed

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