Cytotoxic Safety & Therapeutic Issues Flashcards
what are reasons why you may not want to administer chemotherapy (5)
- signs of infection
- vomiting or diarrhea
- anorexia, inappetance
- PUPD
- concurrent medications
what should you do before deciding if it is safe to administer chemo (2)
- physical exam
- routine blood tests (renal, liver and hematology)
what is myelosuppression
bone marrow suppression
what is the order of cells that are susceptible to myelosuppression
- neutropenia (shortest half life)
- thrombocytopenia
- anemia
how is myelosuppression prevented
check hematology prior to chemo
reduce/delay chemotherapy
what is the number of neutrophils that would be considered too low
>2.5 x 10^9/L
describe what actions would be taken in mild, moderate and severe neutropenia during chemo treatment
how is chemotherapy drugs dosed
according to body surface area
what is the formula for chemotherapy drug dosing
BSA = K x BWt (grams)^2/3/10^4
K = 10.1 dogs
K = 10.0 cats
calculate the dose of vincristine to administer to a 30kg dog
vincristine = 0.7mg/m^2
m^2 = 0.965m^2
vincristine = 0.7mg/m^2
= 0.7 x 0.965 = 0.68mg
concentration is 1mg/ml so dose to give is 0.68ml
calculate the dose of cyclophosphamide to give to a 20kg dog
tablets = 50mg/m^2
m^2 = 0.74m^2
cyclophosphamide tabelts = 50mg/m^2
= 50 x 0.74 = 37mg
tablets available as 50mg = dilemma do not split cytotoxic drugs
how do you solve dosing dilemmas (can’t spit tablets)
- increase dosing interval
- get drugs reformulated to match exact dose
who should never handle cytotoxic drugs
- under 18y
- pregnant or breastfeeding women
- immunocompromised people
what are the risks when handling cytotoxic drugs (6)
- absorption via skin or mucus membranes
- aerosol formation when removing liquid chemotherapy
- inhalation
- self-inoculation when administering injectable agents
- handling of waste
- patient excreta
how do you minimze exposure to cytotoxic drugs
- don’t eat, drink, store food, smoke or apply makeup in areas where cytotoxic drugs are stored, prepared or administered
- use visual warnings (signs, hazard tape)
- use of best practice when handling drugs & waste
- wear PPE