Special Transfusion Situations

Question 1

technique of extra-corporeal life support which uses heart-lung bypass techniques for days or weeks to support lung and/or heart function

Answer 1

ECMO

Question 2

indication for ECMO

Answer 2

underlying disease process associated with mortality of >80% which has not responded to conventional ventilator support and medical therapies but that is still potentially reversible

Question 3

process of ECMO

Answer 3

draining venous blood
removing CO2
adding O2 through artificial lung
returning warmed, oxygenated blood to circulation
allow normal aerobic metabolism while lung and/or heart “rest” occurs

Question 4

indication for neonatal ECMO

Answer 4

term neonates with respiratory failure due to severe meconium aspiration syndrome, persistent pulmonary hypertension
preterm neonates with SIDS

Question 5

pediatric indication for ECMO

Answer 5

septic shock

Question 6

adult indications for ECMO

Answer 6

acute respiratory or cardiac failure
respiratory failure not corrected by ventilation alone
refractory cardiogenic shock
cardiac arrest
failure to wean from cardiopulmonary bypass after cardiac surgery
as a bridge to either cardiac transplant or placement of ventricular assist device

Question 7

2 types of ECMO

Answer 7

venoarterial (VA)

venovenous (VV)

Question 8

venoarterial ECMO

Answer 8

drainage through a vein
blood return through an artery
oxygenated blood to aorta and systemic circulation
bypasses heart and lung

Question 9

ECMO that bypasses heart and lung

Answer 9

venoarterial

Question 10

ECMO that takes oxygenated blood to aorta and systemic circulation

Answer 10

venoarterial

Question 11

venovenous ECMO

Answer 11

drainage through a vein
blood return through a vein
oxygenated blood to right side of heart
bypasses lungs only

Question 12

ECMO that bypasses lungs

Answer 12

venovenous

Question 13

ECMO that takes blood to right side of heart

Answer 13

venovenous

Question 14

ECMO mainly used in people with heart problems or blood pressure problems

Answer 14

venoarterial

Question 15

ECMO that supports heart and lungs

Answer 15

venoarterial

Question 16

ECMO that provides higher oxygenation levels

Answer 16

venoarterial

Question 17

ECMO with higher risk of systemic embolisms

Answer 17

venoarterial

Question 18

ECMO used for patients who need mainly lung support

Answer 18

venovenous

Question 19

packed cell support for ECMO

Answer 19

20 mg/kg Hct <35

Question 20

cryoprecipitate support for ECMO

Answer 20

1 unit/kg if fibrinogen <150 +/- 10 mg/dl

Question 21

FFP support for ECMO

Answer 21

10 ml/kg if PT >17

Question 22

platelet support for ECMO

Answer 22

maintain platelet count >150,000 to prevent intracranial hemorrhage

Question 23

why are Hgb S negative red cells used in ECMO?

Answer 23

red cells may be exposed to hypoxia and severely abnormal metabolic conditions

Question 24

why do ECMO patients require aggressive anticoagulation?

Answer 24

large area of artificial surface in contact with blood in oxygenator causes activation of coagulation factors and platelets

Question 25

causes of massive transfusion

Answer 25

trauma
GI bleed
hemorrhage during or following delivery
major surgical procedures

Question 26

rate-related complications of massive transfusion

Answer 26

hypocalcemia
hyperkalemia
hypomagnesemia
hypothermia
acidosis

Question 27

volume-related complications of massive transfusion

Answer 27

dilutional thrombocytopenia
dilution of procoagulant factors
dilution of anticoagulant factors

Question 28

massive transfusion protocol utilized by military and many trauma institutions

Answer 28

1:1:1 rbc:FFP:plt concentrate

1 plateletpheresis for every 10 RBCs and 10 FFP

Question 29

evidence-based guidelines for high risk coronary patients

Answer 29

increased risk of bleeding
higher transfusion trigger (Hgb 10 g/dl)
renal insufficiency
repeat procedure

Question 30

how does massive transfusion protocol result in increased bleeding?

Answer 30

rapidly replacing blood volume with packed cells and IV fluids eventually dilutes clotting factors and platelets

Question 31

indications for intra-operative cell salvage

Answer 31

anticipated blood loss >20%
crossmatch compatible blood unobtainable
patient unwilling to receive allogeneic

Question 32

common cardiac indications for intra-operative cell salvage

Answer 32

valve replacement

redo bypass grafting

Question 33

common orthopedic indications for intra-operative cell salvage

Answer 33

major spine surgery
bilateral knee replacement
revision of hip replacement

Question 34

contraindications for intra-operative cell salvage

Answer 34

clotting agents, irrigation solutions
contaminants (urine, bone chips, fat, bowel contents, amniotic fluid, infection, amniotic fluid)
malignancy
hematological disorders (sickle cell, thalassemia)
carbon monoxide
catecholamines

Question 35

acceptable anticoagulants for intra-operative cell salvage

Answer 35

CPD/ACD or heparinized saline

Question 36

expiration of washed cells in intra-operative cell salvage

Answer 36

6 hours if stored at room temp

24 hours if stored in monitored fridge at 1-6C

Question 37

steps of intra-operative cell salvage

Answer 37

• shed blood aspirated from surgical field into filtered cardiotomy reservoir, may be anticoagulated
• whole blood separated by centrifugation to pack red cells and remove lighter plasma, irrigation saline, hemolyzed cells and anticoagulant
• saline added to continue removing contaminants and leaving only RBCS suspended in normal saline
• bag labeled as washed cells along with patient name and ID and time collection began