Haematology Flashcards
What different information can you get from bone marrow aspirate v trephine
aspirate = myeloid:erythroid, orderly/complete maturation, presence of abnormal cells
trephine = cells:fat, no of diff cells present, presence of abnormal infiltrates, changes to stroma/bone
Which area does a leukaemia affect
bone marrow
Which area does a lymphoma affect
lymph nodes
What is the difference between acute and chronic haematological malignancies?
acute = cell growth arrested at early stage of differentiation`
chronic = cell growth arrested at later stage of development. already partially developed
What are the features of ALL
most common in children 2-4y infection bleeding/brusing tiredness bone pain (secondary to bone marrow infiltration) splenomegaly hepatomegaly testicular swelling
What are the risk factors for ALL
genetics
What investigations need to be done in ALL
FBC, clotting, LDH, U+E LFT
blood film
bone marrow aspirate and trephine
immunophenotyping
what is the management of ALL
remission induction - chemo
maintenance
CNS prophylaxis
What are the features of AML
most common 50-60y anaemia: pallor, lethargy, weakness neutropenia: whilst white cell counts may be very high, functioning neutrophil levels may be low leading to frequent infections etc thrombocytopenia: bleeding splenomegaly bone pain
What conditions can progress into AML
Myelodysplastic syndrome
aplastic anaemia
myelofibrosis
What investigations need to be done in AML
FBC, clotting, LDH, U+E, LFTs
blood film
bone marrow aspiration
what is the management of AML
induction
post remission consolidation
stem cell transplantation
Which cells are affected in CLL
monoclonal proliferation of well-differentiated lymphocytes which are almost always B-cells
immature, unreactive, accumulate in bone marrow, don’t die when they should
What are the features of CLL
often none constitutional: anorexia, weight loss bleeding, infections lymphadenopathy more marked than CML splenomegaly
What investigations need to be done in CLL
FBC blood film bone marrow aspirate and trephine lymph node biopsy immunophenotyping
What cells are seen on a blood film in CLL
smear/smudge cells
What is the genetic abnormality present in most CML
philadelphia chromosome
translocation between 9 and 22
BCR-ABL gene codes for a fusion protein which has tyrosine kinase activity in excess of normal
Which cells are affected in CML
myeloproliferative disorder of haemopoeitic stem cells affecting one or all cell lines - erythroid, platelet, myeloid
Describe the phases of CML
chronic - 4-5y. asymptomatic, immune system fine
accelerated - 15-29% blasts in the marrow/blood, low platelets, RBC and granulocytes
blastic - >=30% blasts in blood/marrow plus severe constitutional symptoms
What are the features of CML
anaemia: lethargy
weight loss
splenomegaly/hepatomegaly
night sweats
What investigations need to be done in CML
FBC LDH
Blood film
bone marrow aspirate and trephine
cytogenetics - philadelphia chromosome
What is the difference between a group and save and a cross match?
group and save - gives blood group and screens for abnormal antibodies. no blood is issued
cross match - patient and donor blood mixed. blood issued if no immune reaction
How are blood samples like group and save and cross match meant to be taken
two separate samples
three points of ID
informed consent from patient for blood transfusion
label bottles by bedside by hand
complete request form by patient’s bedside
What is the threshold for red cell transfusion
Hb <70g/L
Hb <80g/L if acute coronary syndrome
What does FFP contain
clotting factors, albumin, immunoglobulin
What are the indications for giving FFP
(i) Disseminated Intravascular Coagulation (DIC);
(ii) Any haemorrhage secondary to liver disease;
(iii) All massive haemorrhages (commonly given after the 2nd unit of packed red cells)
What are the indications for giving platelets
(i) Haemorrhagic shock in a trauma patient;
(ii) Profound thrombocytopenia <20 x 109/L
(iii) Bleeding with thrombocytopenia - if < 100 x 10 9 for patients with severe bleeding, or bleeding at critical sites, such as the CNS
(iv) Pre-operative platelet level <50 x 109/L
What does cryoprecipitate contain
fibrinogen
von willebrand factor
factor VII
fibronectin
What are the indications for giving cryoprecipitate
(i) DIC with fibrinogen <1g/L;
(ii) von Willebrands Disease; or
(iii) Massive haemorrhage
When is CMV -ve blood inidcated
if risk of congenital CMV infection - causes cerebral palsy or sensorineural deafness
pregnancy
intrauterine transfusion
neonates <28 days
When is irradiated blood indicated
if increased risk of graft versus host disease
eg:
Those receiving blood from first or second-degree family members
Patients with Hodgkin’s Lymphoma
Recent haematpoietic stem cell (HSC) transplants
After Anti-Thymocyte Globulin (ATG) or Alemtuzumab therapy
Those receiving purine analogues (e.g. fludarabine) as chemotherapy
Intra-uterine transfusions
congenital cellular immune deficiency
What onservations should be carried out when giving a blood transdusion
obs including temperature
before, after 1 min, after 15 mins, after 1 hour, at completion
What size cannula should blood be given through? Why?
green - 18G
grey - 16G
prevents shearing of the red blood cells as they through a too narrow tube
What are some acute complications of a blood transfusion
acute haemolyic non-haemolytic febrile allergic infective TRALI fluid overload hyperkalaemia
What causes an acute haemolytic reaction to a blood transfusion
Incompatible transfused red cells react with the patient’s own anti-A or anti-B antibodies or other alloantibodies (eg, anti-rhesus (Rh) D, RhE, Rhc and Kell)
Complement can be activated and may lead to disseminated intravascular coagulation (DIC).
What are the features of acute haemolytic reaction to a blood transfusion
within a few minutes of start of transfusion:
fever
abdominal and chest pain
agitation
hypotension
How should an acute haemolytic reaction to a blood transfusion be managed
stop the transfusion immediately!!!
Keep the intravenous (IV) line open with saline.
Give oxygen and fluid support.
Monitor urine output, usually following catheterisation. Maintain urine output at more than 100 ml/hour, giving furosemide if this falls.
Consider inotrope support if hypotension is prolonged.
Treat DIC appropriately - seek expert advice early and transfuse platelets/fresh frozen plasma (FFP) guided by the coagulation screen and bleeding status.
Inform the hospital transfusion department immediately.
What causes a non-haemolytic febrile reaction to a blood transfusion
patient antibodies to transfused white cells.
What are features of a non-haemolytic febrile reaction to a blood transfusion
occurs near end of or after transfusion
fever >1 degrees from baseline
rigors
How should a non-haemolytic febrile reaction to a blood transfusion be managed?
lowing or stopping the transfusion
giving paracetamol.
What causes an allergic response to a blood transfusion
antibodies that react with proteins in transfused blood components.
IgE or IgG mediated
What are the features of an allergic response to a blood transfusion
Urticaria and itching are common within minutes of starting a transfusion.
anaphylaxis:
acutely dyspnoeic due to bronchospasm and laryngeal oedema and may complain of chest pain, abdominal pain and nausea.
How is an allergic response to a blood transfusion managed?
slowing the transfusion
giving antihistamine
transfusion may be continued if there is no progression at 30 minutes.
anaphylaxis: IM adrenaline, steroids, bronchodilators
What is TRALI and what causes it?
Transfusion-related acute lung injury
donor plasma contains antibodies against the patient’s leukocytes.
leads to acute respiratory distress
What are the features of TRALI
within 6 hours of transfusion
dyspnoea non-productive dry cough hypoxia frothy sputum fever rigors
What are the features of TRALI on CXR
multiple perihilar nodules
infiltration of the lower lung fields
How is TRALI managed
Give high-concentration oxygen, IV fluids and inotropes (as for acute respiratory distress syndrome).
SENIOR HELP
Monitor blood gases, serial CXR and CVP/pulmonary capillary pressure.
Ventilation may be urgently required - discuss with ICU.
What are some long term complications of blood transfusion
infection iron overload Graft versus host disease post transfusion purpura delayed haemolysis of red cells
What causes graft versus host disease
T lymphocytes
What are the features of GvHD
occurs between day 4 and day 30 following transfusion
high fever
diffuse erythematous skin rash progressing to erythroderma, diarrhoea and abnormal liver function.
Patients deteriorate with bone marrow failure and death occurs through overwhelming infection.
What causes post transfusion purpura
platelet-specific alloantibodies,
What are the features of post transfusion purpura
occurs 5-9 days following transfusion.
Bleeding associated with a very low platelet count develops
Which patients are at increased risk of allergic reaction to a blood transfusion
those with severe IgA deficiency
they may develop antibody to IgA
How is a microcytic or normocytic anaemia managed in pregnancy
oral iron should be considered as the first step,
further investigations only required if no rise in haemaglobin after 2 weeks.
Which blood product carries the highest risk of bacterial infection with transfusion? Why?
platelets
stored at room temperature
How should a patient on warfarin with a major bleed be managed
STOP warfarin
5mg Vit K IV
FFP
How should a patient on warfarin with a minor bleed and INR >5 be managed
STOP warfarin
1-3mg Vit K IV - repeat if INR still >5 at 24 hours
restart warfarin when INR <5.0
How should a patient on warfarin with no bleed and INR >8 be managed
STOP warfarin
1-5mg Vit K PO - repeat if INR still >5 at 24 hours
restart warfarin when INR <5.0
How should a patient on warfarin with no bleed and INR 5-8 be managed
withhold 1-2 doses of warfarin
reduce the maintenance dose
