Clinical Haematology/Oncology Flashcards
Causes of anaphylaxis?
Foods
Insect venom
Medications (penicillin, NSAIDs, Chemotherapy)
Latex
Idiopathy
Pathophysiology of anaphylaxis?
Primarily and IgE mediated hypersensitivity reaction involving the rapid release of inflammatory mediators from mast cells and basophils
Clinical features of Anaphylaxis
Airway problems may include:
swelling of the throat and tongue →hoarse voice and stridor
Breathing problems may include:
respiratory wheeze
dyspnoea
Circulation problems may include:
hypotension
tachycardia
generalised pruritus
widespread erythematous or urticarial rash
Acute Management of Anaphylaxis?
IM adrenaline
< 6months 100-150mcg
6 months - 6 years - 150mch
6-12 years 300mcg
> 12 years and adults - 500 mcg
Adrenaline can be given every 5 minutes if needed.
The best site for adrenaline is the anterolateral aspect of the middle third of the thigh.
Management of anaphylaxis following stabilisation?
Non-sedating oral antihistamines
Serum tryptase levels will be raises in true episode of acute anaphylaxis and rain elevated for up to 12 hours.
Refer to specialist allergy clinic
Adrenaline injector provided to patient - should be prescribed 2 and training on how to use it
what is defined as refractory anaphylaxis?
defined as respiratory and/or cardiovascular problems persist despite 2 doses of IM adrenaline
IV fluids should be given for shock
expert help should be sought for consideration of an IV adrenaline infusion
when should patients be discharged after anaphylaxis?
fast-track discharge (after 2 hours of symptom resolution):
good response to a single dose of adrenaline
complete resolution of symptoms
has been given an adrenaline auto-injector and trained how to use it
adequate supervision following discharge
minimum 6 hours after symptom resolution
2 doses of IM adrenaline needed, or
previous biphasic reaction
minimum 12 hours after symptom resolution
severe reaction requiring > 2 doses of IM adrenaline
patient has severe asthma
possibility of an ongoing reaction (e.g. slow-release medication)
patient presents late at night
patient in areas where access to emergency access care may be difficult
observation for at 12 hours following symptom resolution
What is Neutropenic sepsis?
Neutropenic sepsis is a relatively common complication of cancer therapy, usually as a consequence of chemotherapy. It most commonly occurs 7-14 days after chemotherapy. It may be defined as a neutrophil count of < 0.5 * 109 in a patient who is having anticancer treatment and has one of the following:
a temperature higher than 38ºC or
other signs or symptoms consistent with clinically significant sepsis
Aetiology of neutropenic sepsis?
coagulase-negative, Gram-positive bacteria are the most common cause, particularly Staphylococcus epidermidis
this is probably due to the use of indwelling lines in patients with cancer
what can be used as prophylaxis of Neutropenic spepsis?
if it is anticipated that patients are likely to have a neutrophil count of < 0.5 * 109 as a consequence of their treatment they should be offered a fluoroquinolone
e.g. ciprofloxacin
Management of neutropenic sepsis?
abx should be started immediate
Pip/taz
Assessed by a specialist and risk stratified to see if they may be able to have OP treatment
if patients are still febrile and unwell after 48 hours an alternative antibiotic such as meropenem is often prescribed +/- vancomycin
if patients are not responding after 4-6 days the Christie guidelines suggest ordering investigations for fungal infections (e.g. HRCT), rather than just starting therapy antifungal therapy blindly
there may be a role for G-CSF in selected patients
what are the features of SVC obstruction?
dyspnoea is the most common symptom
swelling of the face, neck and arms - conjunctival and periorbital oedema may be seen
headache: often worse in the mornings
visual disturbance
pulseless jugular venous distension
causes of SVC obstruction?
common malignancies: small cell lung cancer, lymphoma
other malignancies: metastatic seminoma, Kaposi’s sarcoma, breast cancer
aortic aneurysm
mediastinal fibrosis
goitre
SVC thrombosis
Management of SVC obstruction
Management is dependant on the individual patient and malignancy and advice should be taken from the oncology team. Options include:
endovascular stenting is often the treatment of choice to provide symptom relief
certain malignancies such as lymphoma, small cell lung cancer may benefit from radical chemotherapy or chemo-radiotherapy rather than stenting
the evidence base supporting the use of glucocorticoids is weak but they are often given
how may blood product transfusion complications classified?
immunological: acute haemolytic, non-haemolytic febrile, allergic/anaphylaxis
infective
transfusion-related acute lung injury (TRALI)
transfusion-associated circulatory overload (TACO)
other: hyperkalaemia, iron overload, clotting
Infective
Creutzfeldt–Jakob disease (leucodepletion has reduced this risk)
Platelets - Common contaminants include Staphylococcus epidermidis and Bacillus cereus.
RBC- BCs are primarily at risk for transmitting viral agents such as HIV, HBV, and HCV. Bacterial contamination is less common but possible, particularly from skin flora during collection.
