CINV Flashcards
what are some triggers to the chemoreceptor trigger zone
pregnancy, cytotoxic agents
what occurs upon afference impulses to vomiting center (VC)
efference impulses to salivation, resp, GI muscles
define acute CINV
n/v occurring within 24 hours of chemo
define delayed CINV
n/v occurring at least 24 hours post-chemo, often peaks 48-72 hours
define breakthrough CINV
n/v that occurs within 5 days post chemo despite optimal anti-emetic regimen used; requires rescue therapy with other antiemetics
define refractory CINV
n/v that occurs in subsequent chemo cycles despite maximum antiemetic protocol
define anticipatory CINV
n/v triggered by sensory stimuli associated with chemo admin
risk factors for CINV
females, history of motion sickness, previous CINV, pregnancy, younger age, anxiety (anticipatory)
what is the goal of antiemetic therapy
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
which drug class is the foundation of most CINV prophylaxis
the “setrons” - aka 5-HT3 RA
ondansetron, granisetron, palonosetron
which setron is best for delayed emesis
palonosetron
side effects of the setrons
headache, constipation
route/dose dependent risk of QT prolongation (mostly with IV ondansetron >16 mg)
which class of antiemetics is a good preventative for HEC, ESPECIALLY delayed CINV, but NOT for breakthrough
NK-1 inhibitors
aprepitant
fosaprepitant
drug interactions with the NK-1 inhibitors?
inhibits metabolism of dexamethasone so must reduce dexamethasone dose by 50%
other important CYP3A4 interactions (ex do not combine with ifosfamide)
which class of antiemetics is good for acute emesis, delayed emesis, HEC, MEC, even low emesis regimens but
NOTTTTT for brain tumors??
adrenal corticosteroids- dexamethasone!