Peri-op & Anaesthesia : Blood Transfusion Flashcards
What is the clinical relevance of Rhesus + or -
- Rhesus + or - the presence or absence of rhesus D surface antigens
- particularly relevant in females
rhesus disease:
* if patient who is RhD- exposed to RhD+ blood antibodies produced in preganncy these anti-D Ab’s may cross the placenta and cause haemolytic disease of the newborn (HDN) if child is RhD+
What does the
ABO blood classification refer to
- the presence of A and/or B surface antigens
What does it mean if the blood is O-ve (Universal donor blood)
no AB or rhesus antigens on donor RBC surface therefore recipient will no amount an immune response
What does it mean if the blood is AB+ve? (universal acceptor)
can give recipient any donor blood as they will not amount an immune response as all the surface antigens are present on their own RBCS
What is involved in Group & Save?
- determines paients ABO and Rh status, also screens the blood for atypical Ab’s
- 40 mins
What is involved in Cross match?
- involves mixing patients blood with donor’s blood to identify any immune response.
- if no response blood can be issued to the patient
Cytomegalovirus is a common congenital infection that may cause sensorineural deafness & cerebal palsy
CMV negative blood must be given to:
- women in pregnancy
- intra-uterine transfusions
- neonates (upto 28 days)
Why is irradiated blood given? Who is it given to?
To reduce risk of graft-versus-host disease in at risk populations:
- blood from 1st or 2nd degree relative
- Hodgkin’s lymphoma
- recent haematpoietic stem cell transplants
- Anti-thymocyte globulin (ATG) or Alemtuzumab therapy
- chemotherapy- purine analogues
- intra-uterine transfusions
How to administer blood products (when to take obs)
Observations must be carried out
* before
* 15-20 minutes after it is started
* at 1 hour
* at completion
NICE- give 1 unit in surgical patient with no active bleeding then reassess
Administering blood:
how may units are prescribed at once
each unit must be prescribed individually.
What gage cannula to adminster blood and why?
Blood products should only be administered through a green (18G) or grey (16G) cannula, otherwise the cells haemolyse due to sheering forces in the narrow tube.
When requesting blood - what strict rules do you have to follow to prevent pt being given the wrong blood
- 3 points of identification (name, Date of Birth (DOB), and patient number).
- **Consent the patient **appropriately – many transfusion request forms will now have a script on them, which you should read to the patient.
- Labeling the bottle at the bedside
- Completing the transfusion request form at the bedside. Before you put the blood bottle into the request bag, check with the patient that they are happy you have labelled things correctly.
What are the four types of blood products that can be given?
Packed red cells
Platelets
Fresh frozen plasma
Cryoprecipitate
In what circumstances should packed red cells be given?
In acute blood loss
In anaemia where Hb<70g/L or <100g/L in pts with CVD.
Over what time period should you transfuse packed red cells?
adminstered over 2-4 hrs
How much should 1 unit of red cells increase a pts HB?
1 unit should increase Hb by 10g/L
(new group & save needs to be carried out for future transfusions)
When are platelets indicated?
indicated in:
* platelet count <30x109 if active bleeding (haematemesis, melaena, prolonged epistaxis)
* threshold higher if bleeding at critical bleeding e.g CNS
* <10x109 if no bleeding / no planned procedure
* pre-op platelet levels of <50 x 109
How long does it take to tranfuse platelets?
administered over 30 mins
How much should a platelet transfusion increase platelet level?
1 adult therapuetic dose should increase levels by around 20-40 x 109 /L
Risk to consider when transfusing platelets?
- Platelet transfusions have the highest risk of bacterial contamination compared to other types of blood products (stored at room temp)
- Non-haemolytic febrile rxn (10-130% platelet ) fever, chills
Components of FFP?
Duration over which it is administered?
Clotting factors
30 minutes
Indications for FFP?
- Disseminated Intravascular Coagulation (DIC)
- haemorrhage secondary to liver disease
All massive haemorrhages (commonly given after the 2nd unit of packed red cells
What does Cryoprecipitate contain?
Indications for cryoprecipitate?
duration over which it is administered?
- DIC with fibrinogen <1g/L
- von Willebrands Disease
- Massive haemorrhage
Administered:
* STAT
Post-op bleeding is common. What are the 3 Main categories of post-op haemorrhage - including timings?
- primary bleeding
- occurs in intra-op period
recorded in patient notes and requires close monitoring - reactive bleeding
- occurs within 24 hrs of the op
often due to stitch that slips or a missed vessel- vessels missed due to intra-op hypotension and vasoconstriction therefore bleeding starts once BP normalises - secondary bleeding-
- occurs 7-10 days post-op
often due to infection resulting in erosion of a vessel
Looking after a post-op pt you suspect could be bleeding: what clinical features to look for on examination and assessment?
- tachycardia
- elevated RR
- reuced urine output
- hypotension (often late sign)
- increase cap refill
Examine for:
* swelling
* discolouration,
* disproportionate tenderness
* periotonism
in Blood, where are antibodies present?
in the plasma
Antigens are on the RBC surface
If a pt is blood group A, what antigens on RBC? What antibodies will be present in plasma?
Antigen A on RBC
Anti-B antibody in plasma
Blood group AB
what antigens on RBC? what anitbodies in plasma?
Antigens A + B
no antibodies in plasma
Blood group O
what antigens on RBC?
What AB in plasma?
no antigens on RBC
Anti-A and Anti -B in plasma
What are allantibodies?
alloantibodies are produced in response to exposure to incompatible blood groups antigens, typically as a result of pregnancy (RH) or transfusion
Alloantibody toward human leukocyte antigens (HLAs) and blood antigens is a major barrier to successful transplantation.
What are critical points in the blood transfusion process?
- Decision to transfuse
- Prescription/request
- Pre-trasnfusion sampling of blood
- Lab testing on blood
- Collection of blood from storage site
- Bedside administration
Acute haemolytic transfusion reaction
- cause
- S&S
- Management
Early signs include fever, abdominal pain, hypotension and anxiety
Late complications include generalised bleeding secondary to DIC
Non-haemolytic febrile transfusion reaction
- cause
- S&S
- Management
Minor Allergic transfusion reaction
- cause
- S&S
- Management
Anaphylaxis transfusion reaction
- cause
- S&S
- Management
TACO - transfusion-associated circulatory overload reaction
- cause
- S&S
- Management
Transfusion-related acute lung injury (TRALI)
transfusion reaction
- cause
- S&S
- Management
Mnemonic for transfusion reactions:
Got a bad unit
G raft vs. Host disease
O verload
T hrombocytopaenia
A lloimmunization
B lood pressure unstable
A cute haemolytic reaction
D elayed haemolytic reaction
U rticaria
N eutrophilia
I nfection
T ransfusion associated lung injury
Options for red cell transfusion in an emergency?
- Packed red cells
- Group specific (but non-crossmatched) blood
- Group O- red cells
How to optimise pt’s Hb in surgery and post-op?
in surgery - Cell salvage
post- op - tranexamic acid
