5. Transfusion Flashcards
(38 cards)
what is transfusion medicine?
branch of medicine concerned w/ transfuion of blood products and all related lab testing
epidemiology of blood transfusions in US?
blood product transfusion is among MOST COMMON INTERVENTIONS performed in healthcare;
21 M transfusions annually in US
across ass med/surg specialties, incl pod and dentistry
blood donates have tremendous impact on reducing morbidity and mortality;
how are blood donors compensated in the US?
In the US, blood donation is for purposes of producing blood components is an ALTRUISTIC, NON-COMPENSATED ACT (w/ no monetary payments or equivalents)
where are blood donations made?
- designated donor centers (e.g. Red Cross)
- mobile blood drives
- hospital settings
what determines if a blood donor is “fit to donate”?
- Donors have to be qualified (deemed fit to donate) at each donation; based on detailed hx questionnaire, interview, and brief physical exam
- May be UNFIT - for reasons that pose risk to blood supply (infectious risk) or to themselves (inability to tolerate donation)
what is the most common blood donation method?
PHLEBOTOMY
- sterile venipuncture by trained professionals
- approx 450-500 mL of whole blood collected
- into bag containing an anticoagulant/preservative solution (CPD, citrate phosphate dextrose)
Other, much less common would be Apheresis
how are blood components separated? into what components?
whole blood –>centrfuged to separate based on density
- packed red blood cells (pRBCs)
- platelet-rich plasma (PRP)
- platelets (PLT)
- fresh frozen plasma (FFP)
how is cryoprecipitate derived?
from fresh frozen plasma (which is a component of platelet-rich plasma
how are the blood components stored at the blood back until need for transfusion?
- packed RBCs: refrigerated, up to 42 days
- platelets: room temp for <5 days
- plasma and cryoprecipitate
- stored frozen up to 1 year
- thawed prior to transfusion
what should be considered prior to transfusion?
- certain unavoidable risks and potential adverse events that may accompany transfusions
- should be treated like any other medical intervention
- consider risks vs/ benefits
- informed consent of recipient
- ONLY TRANSFUSE WHEN ABSOLUTELY NECESSARY to avoid unnecessary risk to patient
Unless pt is in an active hemorrhage situation, how do you administer transfusions?
Transfuse 1 unit/bag of blood products at a time, THEN REASSESS the patient’s transfusion needs afterwards
indications for pRBC infusion?
ONLY for increasing oxygen carrying capacity, eg:
- symptomatic anemia
- acute blood loss
THERE ARE NO OTHER MEDICALLY JUSTIFIABLE INDICATIONS
what is the transfusion threshold for pRBCs?
Hemoglobin < 7-8 g/dL
*if labs are the only thing you’re looking at
**not applicable for all patient populations; must consider clinically relevant factors
what is the expected response to transfusion with 1 unit pRBCs?
1 unit pRBCs –> hemoglobin expected to increase by 1 g/dL
purpose and indications of using PLATELET TRANSFUSION?
To correct thrombocytopenia (decreased platelet levels)
- active bleeding
- risk of bleeding (e.g. prior to surgery)
- dysfunctional platelets (less common)
what are the transfusion thresholds for platelets in the following situations?
- stable, w/o active bleeding
- active bleeding
- surgery (non-neurosurgical)
- neurosurgery
If pt is otherwise stable w/o active bleeding, platelets can get low to about 10,000 w/o risk of bleeding;
NO NEED TO TRANSFUSE IF ABOVE THE THRESHOLDS LISTED
what are the 2 types of platelet products?
which is more commonly used today?
-
Whole blood-derived individual units - only inc 5,000-10,000 /mL
- antiquated, have fallen out of favor
-
Apheresis units (*modern, special collection method)
- 6x as potent as whole blood-derived units
what is the expected resopnse to administering 1 apheresis Platelet unit?
1 apheresis Platelet unit →
Platelet increase by 30,000–60,000 /mL
what are the indications to administer Plamsa?
to simultaneously correct the deficiency of multiple coagulation factors, as seen in;
- ongoing massive bleeding
- disseminated intravascular coagulation (DIC)
could plasma be administered for Hemophilia?
why or why not?
Plasma transfusion should NOT be used for most isolated single coagulation factor deficiencies (i.e. hemophilia);
**there are better pharmacologic options
how are PLASMA transfusion thresholds gauged?
what is the expected response to transfusion?
- Plasma thresholds difficult to gauge
- Based on clinical situation + coagulation labs (PT, aPTT)
- Expected response to transfusion - UNPREDICTABLE
Describe the dosing of plasma transfusion
Dosing of plasma is weight-based;
e. g. 10-20 mL per kilogram (patient weight)
* Rather than a 1 bag per transfusion model;*
In general, how is pediatric dosing for transfusion calculated?
all transfusions are weight-based;
in adults, plasma transfusion is weight-based, as is chemotherapy
what are the indications of cryoprecipitate?
Indicated to correct hypofibrinogenemia (LOW FIBRINOGEN)
(most relevant coagulation factor in cryoprecipitate is FIBRINOGEN)
