CINV

Question 1

what are some triggers to the chemoreceptor trigger zone

Answer 1

pregnancy, cytotoxic agents

Question 2

what occurs upon afference impulses to vomiting center (VC)

Answer 2

efference impulses to salivation, resp, GI muscles

Question 3

define acute CINV

Answer 3

n/v occurring within 24 hours of chemo

Question 4

define delayed CINV

Answer 4

n/v occurring at least 24 hours post-chemo, often peaks 48-72 hours

Question 5

define breakthrough CINV

Answer 5

n/v that occurs within 5 days post chemo despite optimal anti-emetic regimen used; requires rescue therapy with other antiemetics

Question 6

define refractory CINV

Answer 6

n/v that occurs in subsequent chemo cycles despite maximum antiemetic protocol

Question 7

define anticipatory CINV

Answer 7

n/v triggered by sensory stimuli associated with chemo admin

Question 8

risk factors for CINV

Answer 8

females, history of motion sickness, previous CINV, pregnancy, younger age, anxiety (anticipatory)

Question 9

what is the goal of antiemetic therapy

Answer 9

complete prevention (0-1 episodes/24 hours) for at least 3 days for high risk (HEC) or 2 days for moderate risk (MEC) after the last dose of chemotherapy

Question 10

which drug class is the foundation of most CINV prophylaxis

Answer 10

the “setrons” - aka 5-HT3 RA
ondansetron, granisetron, palonosetron

Question 11

which setron is best for delayed emesis

Answer 11

palonosetron

Question 12

side effects of the setrons

Answer 12

headache, constipation
route/dose dependent risk of QT prolongation (mostly with IV ondansetron >16 mg)

Question 13

which class of antiemetics is a good preventative for HEC, ESPECIALLY delayed CINV, but NOT for breakthrough

Answer 13

NK-1 inhibitors
aprepitant
fosaprepitant

Question 14

drug interactions with the NK-1 inhibitors?

Answer 14

inhibits metabolism of dexamethasone so must reduce dexamethasone dose by 50%
other important CYP3A4 interactions (ex do not combine with ifosfamide)

Question 15

which class of antiemetics is good for acute emesis, delayed emesis, HEC, MEC, even low emesis regimens but
NOTTTTT for brain tumors??

Answer 15

adrenal corticosteroids- dexamethasone!

Question 16

pearls for dexamethasone?

Answer 16

dose reduce with aprepitant/fosaprepitant
may be modified when the chemo regimen already includes a steroid
not recommended with immunotherapies
not used in brain tumors

Question 17

adverse effects of dexamethasone

Answer 17

HTN, DM, GI upset/bleeding, agitation, itching, nerves, vomiting

Question 18

which drug is the newest preventative, also used for breakthrough CINV, can be used prn or for palliative care nausea, and has replaced haloperidol in many settings

Answer 18

olanzapine

Question 19

olanzapine adverse effects

Answer 19

increased risk of EPS when used with metoclopramide or haloperidol
QT prolongation
CNS depression
risk for falls in elderly
orthostatic hypotension

Question 20

which drug classes are used for prevention

Answer 20

setrons
NK-1 inhibitors
adrenal corticosteroids
olanzapine

Question 21

which drug classes are used for breakthrough

Answer 21

benzodiazepines (lorazepam)
metoclopramide
cannabinoids
phenothiazines or haloperidol

Question 22

how is lorazepam used for CINV?

Answer 22

it is not a true antiemetic, more an amnestic. helpful for anticipatory emesis when started prior to triggers

Question 23

side effects of metoclopramide

Answer 23

EPS

Question 24

what cannabinoid may be used for breakthrough CINV

Answer 24

dronabinol. also useful for appetite
no evidence supports marijuana over this

Question 25

side effects for phenothiazines/haloperidol

Answer 25

CNS depression, fall risk, EPS, QT prolongation
IV use- hydroxyzine, promethazine- severe tissue injury- contraindication for peripheral vein injection

Question 26

how to build the regimen

Answer 26

start with risk level of regimen
consider concurrent meds/diseases (QT, Beers, DDI)
consider effects on lifestyle (is sedation ok)
PO vs IV drugs
plan for breakthrough needs rather than wait

Question 27

how long to protect patients for period of CINV risk

Answer 27

HEC at least 3 days
MEC at least 2 days after last dose of chemo

Question 28

is PO or IV 5-HT3 RA more efficacious

Answer 28

they have equivalent efficacy when used at the appropriate dosing

Question 29

what is the best approach for minimal and low emetic risk regimens?

Answer 29

avoid scheduled antiemetics- opt for breakthrough approach

Question 30

what to do for breakthrough plan

Answer 30

it is easier to prevent n/v than treat it
always give a prn medication for immediate action
in the future- may need to change the initial preventative regimen

Question 31

definition of high emetic risk

Answer 31

> 90% frequency of emesis

Question 32

recommendation for high emetic risk regimen

Answer 32

4 drugs

Question 33

definition of moderate emetic risk

Answer 33

> 30-90% frequency of emesis

Question 34

recommendation for moderate emetic risk

Answer 34

3 drug regimen

Question 35

non-pharm strategies

Answer 35

eat small meals
drink water, sports drinks, pedialyte, flat ginger ale
eat cool foods
avoid hot foods, candles, perfumes
sniff good smells- aromatherapy, mint
fresh air

Question 36

what if multiple consecutive days of chemo?

Answer 36

delayed CINV may superimpose on acute
5HT3 RA prior to every day’s dose
dexamethasone daily then continued 2-3 days after
NK1 inhibitors daily, then 2-3 days after

Question 37

what are some of the high risk (>90%) for CINV drugs

Answer 37

anthracycline/cyclophosphamide
carmustine
cisplatin
cyclophosphamide
dacarbazine
mechlorethamine
streptozocin