test 4 Flashcards

Question

World War II

Answer 1

◦ Storage problem overcome with the advent of blood banks

Answer 2

 Use of blood alternatives ◦ Switched from plasma to Dextran (volume expander)  Sugar substrate  Due to incidence of hepatitis transmittal

Answer 3

 Started looking into “blood substitutes” | ◦ Searched for oxygen carrier

Answer 4

◦ Surgeon Gerald Klebanoff (Vietnam Vet) introduced the first cell saver in a military hospital.

Answer 5

◦ Hemopheliacs | ◦ Israeli army discovered potential to stop life threatening hemorrhage

Answer 6

 Hospital Commitment - EVERYONE (Administration, Physicians, Nurses, etc.)  Coordinator to recruit physicians dedicated to the mission in a variety of specialties

Answer 7

◦ Age – tolerance of anemia is age dependent  Elderly don’t tolerate  As age increases, risk of transfusion increases ◦ Gender – women are more likely than men to get transfused  Lower hct and prone to blood loss with menses ◦ Weight/Height – required to do calculations  Small patients and obese patients are at risk for transfusion  Race/ Ethnicity/ Background/ Religion  Anemia and Coagulation disorders are associated with certain races

Answer 8

``` ◦ Anemia ◦ Hemostatic disturbances ◦ Medical conditions increasing perioperative blood loss ◦ Obstacles to surgical hemostasis ◦ Factors decreasing anemia tolerance ```

Answer 9

◦ Hgb ◦ PT/INR / PTT ◦ Platelet Count and Platelet Function Tests

Answer 10

◦ Optimize Hgb prior to surgery

Answer 11

◦ Risk of hemorrhage during surgery (hyperviscosity) | ◦ Plebotomy

Answer 12

◦ Drugs (not anticoagulants) that have increased bleeding risk

Answer 13

```  Obtain a focused history  Ask about patient-related obstacles to transfusion-free therapy  Lab work  Treat any coagulopathies  Treat any anemia  Treat Polycythemia  Avoid pharmacological coagulopathies ```

Answer 14

 Help correct any coagulopathies/anemia preop.  Help position the patient to decrease blood loss  Provide controlled hypotension  Keeping patient warm ◦ Optimizes clotting  Choice of Drugs  Timing of fluid administration ◦ Restrict until surgical hemostasis is achieved  Intravascular pressure is not too high

Answer 15

◦ Donation where the donor and recipient are identical  Patient donates blood to be used on themselves during surgery.  Avoids use/ risks of donor blood  May not be practical or cost effective for most cardiac surgeries  Requires a hematocrit of 33%  Donation of whole blood can be split ◦ Allows not only donation of RBC, but also FFP ◦ Requires special order from physician  Plateletpheresis and Plasmapheresis ◦ Allows the donation of platelets and plasma

Answer 16

``` ◦ Recent MI ◦ CHF ◦ Aortic Stenosis ◦ Transient Ischemic Attacks ◦ Hypertension ◦ Unstable Angina ◦ Bacteremia ```

Answer 17

- donate to yourself but do not change your volume by adding crystalloid  Spares platelets from bypass ◦ Retain/ preserve function  Requires a hct of 35%  Remove about 500-1000mL (1-3 units) ◦ Depends on starting hct ◦ Depends on age of patient ◦ Depends on BSA ◦ Depends on coexisting conditions  Blood is placed in a bag with anticoagulant ◦ Usually CPD (citrate-phosphate-dextrose)  Reinfused after protamine is administered

Answer 18

``` ◦ COPD ◦ CHF ◦ CAD (CABG) ◦ Unstable Angina ◦ Renal Insufficiency ◦ Severe Aortic Stenosis ◦ Coagulopathy ```

Answer 19

 Performed prior to bypass  Arterial and venous cannula are in place  Use the patient’s blood pressure to displace prime.  Remove prime via: ◦ Stopcock on ALF ◦ Arterial sampling manifold ◦ Y’s in circuit  Can be done quickly  Must closely watch patient’s pressures ◦ Remove about 200-600mL of Prime

Answer 20

 Requires the use of VAVD  Venous line is emptied prior to connection to the venous cannula  Volume is removed to a bag and discarded or sequestered  Eliminates about 400-1000mL  Cautions: ◦ Only works if patient has adequate volume pre-op ◦ If patient is dry (not a lot of volume), will need the volume anyways

Answer 21

```  AKA: Miniaturized Extracorporeal Circuits  Decreases foreign surface area  Decreases prime volume  Decreases blood-air contact  Attempt to: ◦ Decrease hemodilution ◦ Decrees inflammatory response ◦ Decrease volume shifts ```

Answer 22

 Closed A-V Loop with centrifugal pump, membrane oxygenator, coated tubing ◦ No venous reservoir ◦ No cardiotomy ◦ Often no heat exchanger or arterial line filter ◦ Centrifugal pump provides kinetic assisted venous drainage and blood flow  Prime volume is about 500mL ◦ Can be decreased with RAPing  Used mostly for CABGs ◦ Some valves have been done

Answer 23

◦ Totally Integrated Devices  Include air handling and elimination systems, centrifugal pump and membrane oxygenator. ◦ Combination of components

Answer 24

◦ Less inflammatory reaction ◦ Less activation of coagulation and fibrinolysis ◦ Less hemodilution ◦ Less use of autologous blood ◦ Marginally improved renal and neurological function  Results in the studies are mixed

Answer 25

◦ Air handling ◦ Requires surgeon to take care to avoid air entrapment around the cannula ◦ More microemboli with MECCs compared to normal circuits ◦ No reservoir = no way to handle excess volume ◦ No immediate volume infusion ◦ No heat exchanger (on most) ◦ Use of separate cell saver (Delay in processing, loss of factors/platelets) ◦ Increased cost ◦ Adaptability when surgical complications/ need requires normal ECC

Answer 26

```  Cut lines short  Get as close to the table as possible  Elevate the reservoir ◦ Use VAVD  Put modular pump heads near outlet/inlet of oxygenator  Dry venous line ◦ Requires VAVD  Go on with low prime volume ```

Answer 27

 Filtration of water across a semipermeable membrane via hydrostatic pressure gradient  Water crosses the membrane which creates a solute concentration gradient  Solutes have a higher concentration in blood so they move to the water side which has a lower solute concentration  So, we’re removing “water”  And electrolytes

Answer 28

 Withdrawing blood from the patient via the arterial line (post bypass)  Running the blood through a hemoconcentrator  Pumping the blood back into the patient via the venous line.  Can use the cardioplegia circuit ◦ Make sure to flush out the cardioplegia solution with blood ◦ Pump flow rate less than MUF flow rate

Answer 29

 Use heparinized saline or CPD as an anticoagulant  Cells are separated from the fluid by a centrifuge ◦ RBC fall to the bottom, Plasma on top  RBC washed with 3x bowl volume (min)  Put in a reinfusion bag for administration  Removes: Fat, air, tissue debris, potassium, hormones, bioactivators, etc.

Answer 30

``` ◦ Delay in processing ◦ Loss of plasma proteins ◦ Loss of coagulation factors and platelets ◦ Expense ◦ Operator attention and time ```

Answer 31

 Blood collected from the mediastinum and pleural cavities post op can be reinfused ◦ Doesn’t clot due to defibrination ◦ Increased level of free Hgb ◦ Contains activated products  ***NOT ideal ◦ Used in urgent situations ◦ Can be processed

Answer 32

 Shed blood can be collected and processed by a cell processing device – Cardiopat  Uses a dynamic disk to process. ◦ Processes a variable volume of blood  Consistently delivers washed RBCs w/ hct of 70-80%  Processes up to 2 liters per hour or as little as 5 mL of RBCs

Answer 33

 Acceptable level varies by institution  Healthy, Good LV Function ◦ Tolerate 20-25%  Those with limited coronary flow, increased metabolic needs, respiratory issues will require increased hematocrits

Answer 34

 Blood conservation is a team approach  Everyone involved in each step of a patient’s care need to be on board ◦ Primary care physicians, nurses, surgeons, anesthesiologists, perfusionists, residents/ fellows ◦ One player not on board can significantly alter the course of that patient’s care.