Cytotoxic safety and therapeutic issues Flashcards
Describe the CHOP protocol to treat lymphomas
Cyclophosphamide
Doxorubicin
Vincristine
Prednisolone
lasts for 25 wks
if in remission and doing well, stop chemo and monitor for recurrence
What is the average survival time of CHOP?
13 months
Describe the COP protocol for lymphomas
Cycylophosphamide
Vincristine
Prednisolone
lasts for 24 months
What is the everage survival time of COP?
8 months
Why are drug combos used?
Combine different mechanisms of action and therefore attack different cell cycle stages
Avoid drug resistance
Maximise cell kill while maintaining acceptable toxicities
What are the steps to determine whether it is safe to give a patient chemo?
Take a detailed history
Any reasons to not give it?- signs of infection?, PUPD? Vomiting or diarrhoea?, anorexia or inappetence? Concurrent medications?
Physical exam
Blood test- renal, liver, haematology. Myelosuppression after chemo = neutropaenia, thrombocytopenia, anaemia
What is the normal neutrophil count in patients?
> 2.5 x 10-9/l
How is drug dose calculated?
BSA= (K x BWT^2/3) / 10^4
K= 10.1 in dogs
10.0 in cats
Why is a catheter used when administering cytotoxic drugs?
ensures accurate dosage
allows thorough flushing with saline
How long is the chemotherapy excretion time?
about 7 days
How would you treat extravasation of cytotoxic drugs?
stop injection, suck back as much as possible
cold compress
talk to your owners
standard wound management
What are some general side effects of chemo?
- peri-vascular reaction
- myelosuppression
- gastrointestinal upsets
- alopecia
- hypersensitivity reactions
- delayed effects- infertility, new tumour induction
What are some hypersensitivity reactions to cytotoxic drugs and how can you prevent them?
Vomiting, restlessness, pruritus, wheals, oedema Dyspnoea, mouth breathing (cat) PREVENTION Use Antihistamine premedication Ensure correct route of administration Monitor closely
What are some after care protocols at home for cytotoxic drugs?
Provide clients with an information sheet – refer to it at discharge
Minimise contact with young children, pregnant women, immunosuppressed people (should these patients start chemo?)
Wear gloves when cleaning up excreta
Discourage pets sleeping in owners beds & wash pet bedding once a week
Observe good hygiene – wash food/water bowls, wash hands after petting
What are some after care protocols with dogs outside for cytotoxic drugs?
Bag & bin poo
Dilute inappropriate urination with water (take a water bottle on walk)
Walk dogs in quiet areas, away from children’s parks etc
