PONV

Question 1

Risk factors for PONV

Answer 1

• 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

Question 2

Peds risk factors for PONV

Answer 2

• 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)

Question 3

Drugs used for PONV

Answer 3

• anticholinergics
• benzamides
• benzos
• butyrophenones
• cannabinoids
• glucocorticoids
• 5HT3 antagonists
• NK1 antagonists
• phenothiazines
• propofol

treatments are additive, multimodal treatment is most effective

Question 4

Anticholinergic (antimuscarinic) used for PONV

Answer 4

Scopolamine

Question 5

Benzamides (D2 receptor antagonist) used for PONV

Answer 5

Metoclopramide (Reglan)

-antiemetic and prokinetic

Question 6

Benzodiazepine (GABA agonist) used for PONV

Answer 6

Midazolam

Question 7

Butyrophenones (antidopaminergics) used for PONV

Answer 7

Droperidol

Haloperidol

Question 8

Corticosteroids used for PONV

Answer 8

Dexamethasone

Question 9

5-HT3 receptor antagonists used for PONV

Answer 9

Ondansetron (also granisetron and palonosetron)

Question 10

Histamine receptor antagonists used for PONV

Answer 10

diphenhydramine, dimenhydrinate (dramamine), hydroxyzine, cimetidine, ranitidine, promethazine (phenergan)

Question 11

NK-1 antagonists used for PONV

Answer 11

aprepitant (emend) 40-80 mg PO
prepitant 125 mg PO, prolonged action

-newest drug class addition to antiemetics

Question 12

Alpha2 agonists used for PONV

Answer 12

-clonidine and dex

Question 13

GI motility drugs used for PONV

Answer 13

• oral antacids
• histamine antagonists
• PPIs
• GI prokinetics: dopamine blockers, macrolides, 5HT4 agonists

Question 14

Receptors involved in N/V

Answer 14

M1
Da-2
H1
5HT3
NK1

Question 15

Brain regions involved in N/V

Answer 15

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)

Question 16

Reducing the risk of PONV

Answer 16

• 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

Question 17

Has black box warning for torsades

Answer 17

Droperidol

Question 18

Phenothiazines (D2 antagonist) used for PONV

Answer 18

Prochlorperazine (compazine)
promethazine
chlorpromazine

-have extrapryamidial side effects

Question 19

List medications used to treat postoperative nausea and vomiting that should be avoided in patients with Parkinson’s disease.

Answer 19

Reglan
Metoclopramide
Droperidol
Inapsine

(any dopamine antagonist)

Question 20

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

Answer 20

GI tract & CRTZ & Medulla = Odansetron
Sm Intestine & Stomach = metoclopraminde
Higher Cortical center = midazolam
CRTZ = marijuana

Question 21

Which medications prevent postoperative nausea and vomiting is especially useful for patients with a history of motion sickness?

Answer 21

Antihistamines or scopolamine (anticholinergic)