Palliative care in gynaecology

Question 1

A women who is undergoing treatment for ovarian cancer complains of nausea. She says she doesn’t feel nausea constantly but it comes on quite suddenly and she vomits a large amount, after which she feels better. What is the most likely cause of her nausea?

Answer 1

Impaired Gastric emptying

Question 2

A women undergoing chemotherapy complains of constant nausea with little relief from vomiting. Is the cause msot likely to originate in the gut, vestibular system or chemoreceptor trigger zone.

Answer 2

Chemoreceptor trigger zone

Question 3

What is the chemoreceptor trigger zone?

Answer 3

An area of the medulla that receives inputs from blood borne drugs or hormones and then communicates with structures in the vomiting centre to cause vomiting.

Question 4

Where is the chemoreceptor trigger zone?

Answer 4

Medulla oblongata

Outside of the blood brain barrier!

Question 5

Describe the pathophysiology of vomiting?

Answer 5

1. Triggers reach the CTZ
2. CTZ then stimulates the vomiting centre. Vomiting centre can also be stimulated by other areas such as the vestibular centre, the enteric nervous system and higher brain centres. Mainly drugs that trigger the CTZ.
3. Motor outputs cause contraction of the diaphragm and anterior abdominal muscles. There is relaxation of the oesophageal sphincter and ejection of gastric contents through the open upper oesophageal sphincter.

Question 6

What receptors are found on the CTZ?

Answer 6

D2
5HT3
(Opiod)
(ACh)
(Substance P)

Question 7

List the various inputs to the vomiting centre

Answer 7

1. CTZ
2. Vestibular system
3. Vagus nerve (gag reflex)
4. Enteric nervous system
5. CNS

Question 8

Is the CTZ inside or outside of the blood brain barrier?

Answer 8

Outside

Question 9

What anti-emetics are used if the nausea is caused by impaired gastric emptying and how do these drugs work?

Answer 9

Metclopramide

• Dopamine (acts at CTZ)
• 5HT3 receptor antagonist
• 5HT4 agonist (Pro kinetic)

Domperidone
- Peripheral dopamine D3 and D4 receptor antagonist (Acts at CTZ and as a prokinetic)

Question 10

What two neurotransmitters mediate the nausea felt due to impaired gastric emptying?

Answer 10

Seratonin

Dopamine

Question 11

Which antiemetic is used to help with the regurgitation seen with some cancer treatments?

Answer 11

Dexamethasone (5HT3 antagonist)

Question 12

Which antiemetics are used to help with the nausea and vomiting caused by the chemical or metabolic effects of chemotherapy?

Answer 12

Haloperidol
- D2 receptor antagonist
Metclopramide
Levomepromazine

Question 13

Which antiemetics are used to help with the nausea and vomiting caused by cerebral disease?

Answer 13

Dexamethasone (5HT3 antagonist)

Cyclizine (H1 receptor antagonist)

Question 14

What neurotransmitters are thought to cause the nausea and vomiting associated with cerebral disease?

Answer 14

GABA

H1

Question 15

What neurotransmitters are thought to cause the nausea and vomiting associated with the vestibular system?

Answer 15

Acetycholine

Histamine

Question 16

Which antiemetics are used to help with the nausea and vomiting caused by the vestibular system?

Answer 16

Cyclizine

Prochlorperazine (D2 receptor antagonist)

Question 17

Which is the most likely cause for nausea that is worse on movement and associated with tinnitus?

Answer 17

Vestibular

Question 18

Which 5HT3 receptor antagonist is used to treat radiation and chemotherapy induced emesis?

Answer 18

Odensatron

Question 19

What is malignant bowel obstruction?

Answer 19

Clinical evidence of bowel obstruction in the setting od a diagnosis of intra abdominal cancer or non intra abdominal cancer with clear intraperitoneal disease.

Question 20

A patient with ovarian cancer presents with abdominal distension and vomiting. One examination you hear tinkling bowel sounds.

Answer 20

Malignant bowel obstruction

Question 21

What drug might help in malignant bowel obstruction?

Answer 21

Dexamethasone

Question 22

Which drug helps with colicy pain?

Answer 22

Hyoscine Butylobromide (Buscopan)

Question 23

Which anti emetic would you give if there was an incomplete metabolic bowel obstruction and no colic in an ovarian cancer patient?

Answer 23

Metclopramide

Question 24

Which two drugs help to reduce GI secretions?

Answer 24

Buscopan (Hyoscine Butylbromide)

Octreotide - somatostain analogue

Question 25

Which drugs help to soften the stool in partial bowel obstruction?

Answer 25

Sodium docusate

Movicol

Question 26

Which drug is used in opiod induced constipation?

Answer 26

Methylnaltrexone

Question 27

List three drugs that give patients a dry mouth?

Answer 27

Anticholinergics
Octeriotide
Haloperidol