Antiemetics ppt Micky Dees Flashcards
josh's guide to no vomit
what is the incidence of postop N/V
10-60%
average 30%
post-op factors that influence PONV
pain dizziness first movement first oral intake opioids
4 top surgical procedures that influence PONV
gyn
abd
ENT
opthalmic
anesthetic factors that influence PONV
premedications
anesthetic agents
gastric distention
duration and depth of anesthesia
patient factors that influence PONV
age gender obesity HX of PONV or motion sickness Anxiety gastroparesis
medical consequences of PONV
patient discomfort interruption in oral intake wound dehiscence electrolyte inbalance dehydration aspiration of vomitus
5 classes of antiemetic agents with ex in each
wait don’t forget the one he did here there is 6
PHENOTHIAZINES -chlorpromazine, chlorpromethazine BUTYROPHENONES -droperedol, haloperidol BENZAMINES - Metaclopromide Anticholinergic - Scopolamine ANTIHISTAMINES -hydroxyzine 5-HT3 receptor antagonist - ondansetron
SE of PHENOTHIAZINES
-chlorpromazine, chlorpromethazine
sedation hypotension extrapyramidal reactions dry mouth urinary retention tachycardia
SE of BUTYROPHENONES
-droperedol, haloperidol
Sedation dystonic reactions hypotension tachycardia extrapyramidal reactions anxiety restlessness arrythmias
SE of BENZAMINES
- Metaclopromide
drowsiness restlessness fatigue anxiety extrapyramidal reactions
SE of Anticholinergic
- Scopolamine
sedation dry mouth visual disturbances memory loss confusion hallucinations
SE of ANTIHISTAMINES
-hydroxyzine
sedation blurred vision dry mouth urinary retention tachycardia
SE of 5-HT3 receptor antagonist
Headache dizziness mild drowsiness constipation arrhythmia's
why do 5-HT3 receptor antagonist avoid dystonic reactions?
not associated with dopamine blockade
where are 5-HT3 receptors located
peripheral
-GI tract
Central
-medulla
Ondansetron intactions with narcotics and NMBDs
none
Ondansetron recommended dose
for PONV
immediately prior to induction
adults 4 mg undiluted over 30 sec (prefer 2-5 min)
peds 0.1mg/kg
Ondansetron recommended dose
for further episodes of nausea/ vomiting
same
adults 4 mg undiluted over 30 sec (prefer 2-5 min)
peds 0.1mg/kg
Ondansetron special concerns for:
elderly?
Renal impairment?
Hepatic insufficiency?
NONe
NOne
None
4 main predictors for PONV
female
Hx of motion sickness. PONV
NON-smoker
postop opioids
PONV video cards
from the young man himself
Causes of PONV
PREMEDS -opioids GASTRIC DISTENTION -ventilation -full stomach -DM DEPTH AND LENGTH OF SX -longer sx higher risk SURGICAL PROCEDUES - gyn -eyes -ABD - ENT POST-OP FACTORS -pain -opioids -dizziness - movement - 1st oral intake PATIENTS AT RISK - age (peds higher) - gender (female higher) - obese -hx of PONV - anxiety - motion sickness
Consequences of PONV
discomfort oral drug disruption wound dehisence aspiration electrolyte disturbances
Now on to RTFF’s highlights from EVERs
rudy rudy rudy (thats me cheering you on)
vomiting is acomplex process coordinated by the vomiting center in the ???????
lateral reticular formation of the medula
explain the process of n/v go deep
- the lateral reticular formation of the medulla receives input from (1) the chemoreceptor trigger zone of the area of POSTREMA in the floor of the fourth ventricule
(2) the vestibular apparatus threough the nucleus vestibularis and cerebellum
(3) higher brain stem and cortical structures
(4) afferents from the GI tract (mainly serotoni-nergic, pharynx, and mediastinum
_____ is an important emetic transmitter in the afferent pathway from the GI tract terminating in the cheorecptor trigger zone and in the nucleus tractus solitarius
Serotoin (5-hydroxytryptamine)
5-HT3
____, _____, _______, and _______ are also implicated in emetic signaling at the chemoreceptor trigger zone and in the nucleus tractus solitarius
dopamine (D2)
acetylcholine
histamine substance P (NK1)
as 5-HT is rapidly removed from plasma by platelets, endothelium, and the liver, peripheral 5-HT release is reflected by analyzing its major metabolite what???
5-hydroxyindole acetic acid (5-HIAA)
The 5-HT3 receptor is a ____-_____ ____ channel and therby differes from other serotonin receptors whose ace=tions are mediated via G-proteins
ligand-gated ion
four 5-HT3 antagonist are now available in the US for PONV what are they
ondansetron
dolaseron
granisetron
palonosetron
which 5-HT3 is available in Europe
tropisetron
5 factors that predispose you to PONV
female sex non-smoking previous PONV hx of motion sickness duration of sx >60 min
the presence of one of these symptoms (female sex, non-smoking, previous PONV, hx of motion sickness,duration of sx >60 min) increased the risk of nausea from 17% to
18, 42, 54, 74 and finialy 87% when all 5 are present
the presence of one of these symptoms (female sex, non-smoking, previous PONV, hx of motion sickness,duration of sx >60 min) increased the risk of vomiting from 7% to
7%, 17%, 25%, 38% and 61% for all 5 factors
