Nausea and Vomiting Flashcards

1
Q

Where is the vomiting centre, what receptors does it contain and what are the 4 main inputs

A

Medulla Oblongata
Mainly histamine and ACh

Inputs: vestibular system, CNS, chemoreceptor trigger zone (4th ventricle), CN IX and X

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What general questions about the PC of vomiting

A
Contents
Timing
Association with eating
Details of pain
Associated symptoms 
Bowel movements
Bowel pathogen exposure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What questions should be asked about PMHx for vomiting

A

Drugs

Abdominal surgeries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does the contents of the vomit suggest (undigested, partially digested, green, faeculent, blood, large volume)

A

Undigested food: oesophageal disorder (achalasia, pharyngeal pouch)
Partially digested: gastric outlet obstruction, gastroparesis e.g. DM
Bile (green): small bowel obstruction (distal to ampulla of vater)
Faeculent: distal intestinal or colonic obstruction
Blood/coffee ground: haematemesis
Large volume: less likely functional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the timing of vomit suggest (early morning, early vs late presentation)

A

Early morning - pregnancy and raised ICP

Early presentation - more likely severe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does vomiting that is associated with eating suggest

A

Within an hour: obstruction in the upper GI tract, proximal to gastric outlet - ask about peptic ulcer disease or dyspepsia history

Longer post-prandial delay - obstruction in lower GI tract, usually small bowel

Early satiety, post-prandial bloating and abdominal discomfort - gastroparesis or outlet obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the following symptoms (with the vomiting) associated with

A

Fever - infectious of inflamm e.g. gastroenteritis, appendicitis, cholecystitis, cholangitis, pancreatitis etc.

Headache, visual disturbance, neuro symptoms - meningitis, encephalitis, migraine, raised ICP

Vertigo, balance isssues - labrythnitis, Meniere’s, BPPV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does a patient’s bowel movements suggest (with vomiting)

A

Delay- long delay suggests obstruction
Constipation - may be due to eating less and then vomiting, but absolute (faeces AND flatus) is serious sign of bowel obstruction

Diarrhoea - infectious gastroenteritis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What questions should be asked to ascertain their exposure to infectious bowel pathogens

A

Any close contacts with the same symptoms? - suggests rotavirus, adenovirus, norovirus (contagious) or sharing of contaminated food S aureus

Living in close quarters? e.g. hospital, army, boarding school, cruise ship

Recent foreign travel?

Unusual meals recently? e.g. barbecue, wedding buffet, late-night kebab, restaurant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which drugs and toxins may lead to vomiting and nausea

A

Medications - opiates, chemotherapy, anitconvulsants, antibiotics etc.
Industrial chemicals - arsenic acid and organophosphate fertilisers
Alcohol and illicit drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the significance of previous abdominal surgery to N+V

A

Prediposes to adhesions (between peritoneum and bowel) -> obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are some red flag symptoms with N+V and their suggested cause

A
Motionless, rigid abdomen 
Bilious or faeculent vomiting, distended abdomen, constipation and pain 
Very high fever 
Early morning + headache 
Central, crushing chest pain 
Meningism 
Reduced consciousness
Haematemesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the suggested conditions with the following red flag symptoms:
Motionless, rigid abdomen

Bilious or faeculent vomiting, distended abdomen, constipation and pain

Very high fever

Early morning + headache

Central, crushing chest pain

Meningism

Reduced consciousness

Haematemesis

A

Motionless, rigid abdomen - peritonitis

Bilious or faeculent vomiting, distended abdomen, constipation and pain - bowel obstruction

Very high fever - infection

Early morning + headache - raised ICP

Central, crushing chest pain - MI

Meningism - meningitis

Reduced consciousness - DKA, meningitis, raised ICP

Haematemesis - varices, bleeding peptic ulcer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What signs should be examined for with presentation of N+V on inspection

A
Hydration status - look at mucous membranes and ask if thirsty 
Abdominal distension 
Scars - ?previous surgery
Hernias
Jaundice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What signs should be examined for with presentation of N+V on palpation and auscultation

A

Tender - inflammation
Signs of dehydration - cold peripheries, delayed CRT
Masses
Guarding and rigidity

Bowel sounds - absent (ileus) or tinkling (obstruction)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What bloods should be ordered for N+V

A
FBC and CRP 
U&Es
VBG 
Liver enzymes 
Amylase 
Group and save
17
Q

What imaging should be ordered for N+V (suspected obstruction)

A
Supine AXR 
Erect CXR (patient must sit up for 10 mins)
18
Q

What “other” investigations should be ordered for N+V

A
Pregnancy test 
Toxicology screen 
Contrast studies 
Abdominal CT
Head CT
19
Q

How is a small bowel obstruction managed before referral to surgery

A

NBM
Drip and suck 0 IV fluids and aspiration via NG tube
Analgesia (avoid opiates and NSAIDs)
Antiemetics

20
Q

What are the indications for surgery for small bowel obstruction

A

Trial conservative management (drip and suck) fails
Signs of strangulation or peritonism
>48 hours after obstruction and it has not resolved
No Hx of abdominal surgery

21
Q

How does DKA present

A
Vomiting
Abdominal pain
Polydipsia
Polyuria 
Headache 
Decreased consciousness and Kussmaul breathing
22
Q

How is anion gap calculated and if it is raised what does it suggest

A

[K+] + {Na+] - [Cl-] - [HCO3-]

presence of extra anion groups in the blood e.g. ketone, lactate, aspirin rather than lack of bicarbonate

23
Q

What is the acute management for DKA

A
ABCDE
IV fluids
IV insulin infusion 
Potassium 
Consider correcting acidosis with bicarb (rare)
24
Q

What advice/medications can be offered to pregnant patients with morning sickness/nausea

A

Eating smaller meals more slowly
Dietary adjustments e.g. avoid spicy, fatty, acidic foods

Anti-emetics e.g. antihistamines (promethazine), electrolyte replacement, thiamine supplements

Severe (hyperemesis gravidarum) - prochlorperazine, chlorpromazine, metoclopramide, ondansteron

25
Q

What is the comments focal neurological deficit in raised ICP

A

CNVI palsy (inability to abduct) as VI has a long intracranial

26
Q

If a dehydrated patients is able to tolerate oral fluids, what is the best fluid to use and why?

A

Oral rehydration solution
Sodium, glucose, water
Correct proportions for optimal use. of the Na-Glucose transporter

Best way is to take “little and often”

27
Q

What is the basis of the over-the-counter pregnancy test

A

Detects beta-hCG, which is produced by the placenta after implantation of the fertilised ovum
Can be detected 12 days after fertilisation

28
Q

What mechanisms may mediate N+V in a patient with widespread metastatic disease + chemotherapy

A
Metabolic: hypercalcaemia, uraemia
Intracranial: raised ICP
GI: constipation, bowel obstruction, ileum, hepatomegaly (presses on stomach)
Anxiety 
Chemo or opiate use
29
Q

What are the complications of vomiting

A

Dehydration and renal impairment
Electrolyte imbalance (hypokalaemia, hypochloraemia)
Metabolic alkalosis
Aspiration ± pneumonia
Mallory-Weiss tear
Boerhaave’s perforation
Loss of tooth enamel in chronic vomiting e.g. bulimia nervosa

30
Q

What pre-operative factors may contribute to nausea and vomiting in post-op patients

A

Patient factors e.g. obesity, female, non-smoker
Prolonged fasting
Anxiety
Previous N+V

31
Q

What intraoperative factors may contribute to nausea and vomiting in post-op patients

A

Opioid use
Inhalation (volatile) anaesthetics
Teicoplanin, syntocinon and ergometrine
Sige of surgery e.g. ENT, gynae, abdominal

32
Q

What post-operative factors may contribute to nausea and vomiting in post-op patients

A
Pain
Post-op opioids
Early intake of food
Dizziness due to dehydration, hypertension 
Ileus
33
Q

How does anti-emetic cyclizine work

A

Antihistamine and antimuscarinic that blocks AChR in the vestibular and vomiting centres. Useful pre-op, motion sickness, labyrinth stuff

34
Q

How does the anti-emetic metoclopramide work

A

Agnost at 5-HT4 (serotonin) receptors and a dopamine antagonist (D2) in the chemoreceptor trigger zone and myenteric plexus of the GI tract.

Prokinetic

CI: bowel obstruction + parkinson’s

35
Q

How does the anti-emetic ondansteron work

A

5-HT3 (serotonin) receptor antagonist working in the CTZ

36
Q

How does haloperidol work as an anti-emetic

A

Antagonist of D2 receptors in the CTZ and myenteric plexus of GI tract.
Removes inhibition to normal motility