PONV Flashcards
Risk factors for PONV
- female
- nonsmoker
- hx of motion sickness or prior PONV
- use of opioids
- age < 50
- use of volatile anestheics
- use of N20 (controversial)
- type of surgery (laparotomies, gyne surgeries, laparoscopic procedures, ENT, plastics, ortho)
- duration of surgery
- gastric distention
Peds risk factors for PONV
- age > 3
- surgery length > 30 min
- strabismus surgery
- hx of prior PONV or a family member with hx
-other types of surgery (herniorrhaphy, tonsillectomy, adenoidectomy, male genitalia procedures)
Drugs used for PONV
- anticholinergics
- benzamides
- benzos
- butyrophenones
- cannabinoids
- glucocorticoids
- 5HT3 antagonists
- NK1 antagonists
- phenothiazines
- propofol
treatments are additive, multimodal treatment is most effective
Anticholinergic (antimuscarinic) used for PONV
Scopolamine
Benzamides (D2 receptor antagonist) used for PONV
Metoclopramide (Reglan)
-antiemetic and prokinetic
Benzodiazepine (GABA agonist) used for PONV
Midazolam
Butyrophenones (antidopaminergics) used for PONV
Droperidol
Haloperidol
Corticosteroids used for PONV
Dexamethasone
5-HT3 receptor antagonists used for PONV
Ondansetron (also granisetron and palonosetron)
Histamine receptor antagonists used for PONV
diphenhydramine, dimenhydrinate (dramamine), hydroxyzine, cimetidine, ranitidine, promethazine (phenergan)
NK-1 antagonists used for PONV
aprepitant (emend) 40-80 mg PO
prepitant 125 mg PO, prolonged action
-newest drug class addition to antiemetics
Alpha2 agonists used for PONV
-clonidine and dex
GI motility drugs used for PONV
- oral antacids
- histamine antagonists
- PPIs
- GI prokinetics: dopamine blockers, macrolides, 5HT4 agonists
Receptors involved in N/V
M1 Da-2 H1 5HT3 NK1
Brain regions involved in N/V
vestibular system - goes to vomiting center (central pattern generator in medulla)
peripheral - GI tract - go to nucleus tractus solitarious in brain stem, near area postrema CRTZ, which communicates with vomiting center (central pattern generator in medulla)
Reducing the risk of PONV
- NSAIDS instead of opioids
- TIVA instead of IAs
- dexamethasone reduces by 25%
- ondansetron reduces by 25%
- (percent reduction is additive!)
- use of propofol
- acupuncture, pressure points
Has black box warning for torsades
Droperidol
Phenothiazines (D2 antagonist) used for PONV
Prochlorperazine (compazine)
promethazine
chlorpromazine
-have extrapryamidial side effects
List medications used to treat postoperative nausea and vomiting that should be avoided in patients with Parkinson’s disease.
Reglan
Metoclopramide
Droperidol
Inapsine
(any dopamine antagonist)
Match the med with the area it works at:
Higher Cortical center
GI tract & CRTZ & Medulla
CRTZ
Sm Intestine & Stomach
Higher Cortical center
Metoclopramide (reglan)
marijuana
ondansetron (zofran)
midazolam
GI tract & CRTZ & Medulla = Odansetron
Sm Intestine & Stomach = metoclopraminde
Higher Cortical center = midazolam
CRTZ = marijuana
Which medications prevent postoperative nausea and vomiting is especially useful for patients with a history of motion sickness?
Antihistamines or scopolamine (anticholinergic)
