Ex: 6 - Nausea/Vomiting (68)

Question 1

Nausea

Answer 1

Sickness at the stomach; an inclination to vomit

Question 2

Vomiting

Answer 2

The ejection of matter forcibly from the stomach through the esophagus and mouth

Question 3

Retching (arcadas)

Answer 3

Making movements of vomiting w/o effect

Question 4

What are other symptoms associated with nausea and vomiting

Answer 4

Pallor
Tachycardia
Diaphoresis

Question 5

Etiology of nausea and vomiting: GI disorders

Answer 5

Influenza
-Intestinal pathogen
-food poisoning
Ulcers; GERD
Pancreatitis
Cholecystitis
Obstruction
Tumors
DM gasteoparesis

Question 6

Etiology of nausea and vomiting: CNS disorders

Answer 6

Anxiety tumors HA

Question 7

Etiology of nausea and vomiting: Pain

Answer 7

Acute or chronic

Question 8

Etiology of nausea and vomiting: Excessive intake of just about anything… pregnancy

Answer 8

Intake:
Man vs Food
Alcohol

Pregnancy
-80% of pregnant women

Question 8

Treatment-induced causes of nausea and vomiting

Answer 8

Cancer chemotherapy
-Varies with agent and dose
Radiation therapy
-CNS and abdominal
Anesthesia (~30%)
-Varies greatly with type

NV associated w/procedures
-Especially abdominal

Question 9

Drug-induced causes of NC cont: Anti-neoplastic agents

Answer 9

Opioids
Aspirin, NSAIDs, etc
Iron
Some antibiotics
-Tetracycline; erythromycin
Estrogens
-High doses
Anti-parkinson meds
SSRIs

Question 10

Complications of NV

Answer 10

Patient discomfort
Dehydration (K+, Na+, Cl-)
Malnutrition
Aspiration Pneumonia
Anxiety; anticipatory NV
Compromise therapy
Decreased QOL

Question 11

Assessment of NV

Answer 11

Number of episodes
Onset
Duration of symptoms
Evidence of dehydration
Severity of nausea
-Visual analog scale
0-10

Question 12

Questions to ask patients:

Answer 12

How long have you had NV?
What color
How often
Is the vomiting related to eating?
-If so, what foods/ and how soon after eating
-Do you have nausea w/o vomiting?

Is the NV associated with…
-Abdominal pain
-Constipation
-Diarrhea
-A loss of appetite
-A change in color of your stool
-A change in color of your urine
-Fever
-Chest pain
-HA
-Hearing loss

Question 13

Pathophysiology of NV

Answer 13

Cortex
-Sensory input
-Anxiety and memory
-Meningeal irritation
-Increased ICP

CTZ
-Drugs, metabolic
Dorsal vagal complex
Multiple receptors

GI
-Serotonin release from mucosal enterochromaffin cells
-obstruction
-stasis
-inflammation

Vestibular
-Motion
-CNS lesions
-Opioids
-aggravates most nausea

when we have agents that impact receptors at multiple places, tend to be more efficacious

Question 14

Patho of NV cont: Site of drug action

Answer 14

Dopamine receptors [D2]
Histamine receptors [H1 and H2]
Muscarinic - cholinergic receptors [M1]
Serotonin receptors [5-HT3]
Neurokinin receptors [NK-1]

Often use antihistamines/antimuscarinics to treat NV

Question 15

Non-pcol management of NV

Answer 15

First steps
-Determine the cause
-Put the gut to rest
-clear liquid diet
-IV hydration

Dietary
-Avoid fatty, fried, sweet and spicy foods
-eat food that is cold or at room temp

Question 16

Non-pharmacologic therapy

Answer 16

Physical
-Avoid unpleasant sights, sounds, and odors that may aggravate NV
-Fresh air
-Avoid sudden movements
-Dim lights
-acupressure
-3 fingers above the wrist
-Pregnancy
-Chemotherapy

Question 17

Nerve stimulation therapy

Answer 17

ReliefBand
-helps the stomach return to a normal rhythm of 3 cycles/min
-Adjustable settings on 2 day and 5 day devices

Question 18

Drug therapy: Antihistamines - Anticholinergics

Answer 18

Meclizine; Dimenhydramine; Scopolamine
MOA:
-Block histamine and or muscarinic receptors in the CTZ and NTS centers
-Interrupt visceral afferent pathways
Side effects: drowsiness, sedation, dry mouth, constipation, blurred vision

Overall, role is limited for moderate to severe NV

Question 19

Drug therapy - Phenothiazines

Answer 19

-Prochlorperazine
-Promethazine
-Chlorpromazine

MOA
-Dopamine inhibition at CTZ
-Comparison of phenothiazines
-Std of care prior to 5-HT3 antagonists

SE
-Dizziness, sedation, dry mouth, hypotension, EPS (abnormal movements that occur when dopamine receptors stimulated)

Question 20

Drug therapy - Serotonin Antagonists

Answer 20

Ondansetron
Granisetron
Palonosetron
Dolasetron

MOA
-Serotonin inhibition at CTZ, VC, and GI tract

Side effects:
-Mild HA; Dizziness; fatigue; constipation
-Recent concern about QT prolongation

Question 21

Advantages/Disadvantages of various Serotonin antagonists

Answer 21

Ondansetron
-Multiple dosage forms; including ODT
-Generic/lower cost <$10 tx course

Granisteron
-Multiple dosage forms: patch; LA injection
-Generic/lower cost <$10 tx course

Dolasetron
-PO only
-$$$

Palonsetron
-Longest DOA - t 1/2 = 40hrs
Brand only, $$$
No PO dosage form

No suppository dosage forms

Question 22

Drug therapt: Neuokinin-1 antagonists

Answer 22

Will not see as much, primarily used for chemotherapy induced NV (CINV)

Aprepitant; Fosaprepitant; Rolapitant

MOA
-Neurokinin receptor inhibition at CTZ, VC, and GI tract

Side effects
-Fatigue; hiccups; constipation; decreased appetite

Question 23

Drug therapy - others

Answer 23

Butyrophenones:
Haloperidol; Droperidol
MOA: Dopamine inhibition at CTZ
Black box Warning: risk of EKG abnormalities - Rarely used

Metoclopramide
-MOA: Dopamine inhibition at CTZ
-Serotonin inhibition at CTZ, VC and Gi tract (high dose)
EPS at high dose (Give with benadryl)

Corticosteroids (Dexamethasone)
MOA: inhibition of cortical input into vomiting center?
Enhances the efficacy of any other antiemetics

Cannabinoids
-MOA: Binds with cannabinoid or CB1 receptors in the brain
Side effects: sedation, dry mouth, euphoria, dysphoria; facial flushing, visual changes

Question 24

Importance of Route of Admin in the Tx of NV

Answer 24

Route of admin: -Po tablet -ODT tablet -PR -IV -IM

Question 25

Tx of motion sickness

Answer 25

**Very common** -1/3 of population very susceptible 1/3 susceptible with rough conditions 1/3 susceptible with extreme conditions -Peak age 12-21 years **Prevention**

Question 26

Treatment of Motion sickness:

Answer 26

**Scopolamine** (Transderm-Scop) -Apply patch before needed -Duration = 72 hours **Dimenhydrinate 50mg** -Dramamine -Oral (30-60 min before needed) **Meclizine 25 mg** -Bonine; Dramamine less drowsy -zentrip -Oral (30-60 min before needed)

Question 27

Tx of NV secondary gastroenteritis or pain

Answer 27

**VERY COMMON** -Treat symptoms while treating the **Cause** -Ondansetron 4-8mg IV/ODT/PO q8-12 hours prn -Promethazine 12.5 -25mg IV/IM/PO q4-6 hrs prn

Question 28

Post Operative NV

Answer 28

Very common with older inhaled agents -Patients with **multiple** risk factors are at highest risk for PONV Most common complication associated w/ambulatory surgery (30-50%) **Prevention**

Question 29

Risk factors for PONV

Answer 29

**Patient-specific factors** -F > M -Non-smoking status -HX of PONV -hx of motion sickness **Anesthetic risk factors** -Intra-operative use of **volatile** anesthetics -less with propofol -Use of nitrous oxide -Type of surgery -Laparoscopy -Craniotomy -ENT

Question 30

Tx of PONV chart

Answer 30

Risk: **Low** -1-2 risk factors Prophylaxis: -No tx necessary Risk: Moderate to high 2+ risk factors Prophylaxis: -Tx with 1 or 2 agents -Only1 agent if propofol is used -5-HT3 antagonists are DOC -All classes can be used **Drugs administered at end of procedure** Risk: Highest -3 or more esp. if prior hx of PONV -**Always use 2 agents** -5-HT3 + metoclopramide or aprepitant Risk: Breakthrough Prophylaxis: -Use an agent from a different class if within 6 hours of original dose -**Amisulpride** (Barhemsys)

Question 31

Treatment of PONV

Answer 31

Aprepitant (Emend) -**40 mg** orally 1 to 3 hours prior to induction of anesthesia -**May be** superior to ondansetron 4mg at both 24 and 48 hrs post-op -Data in trials was not **statistically** significant **Amisulpride (Barhemysys)** -5-10 mg IV infused over 1-2 minutes -Selective dopamine-2 and dopamine -3 antagonist -Not indicated for prophylaxis -has been associated with QT prolongation

Question 32

Monitoring antiemtic therapy

Answer 32

**Efficacy** -Volume -Frequency and duration -Nausea rating -Ability to eat -PRN doses of anti-emetic agents -QOL ratings **Toxicity** -Sedation/drowsiness -Dizziness -Diarrhea -HA -Anticholinergic SE -EPS