Management Of Nausea And Vomiting In

1
Management Of Nausea And Vomiting In Palliative
Care
2
INCIDENCE OF NAUSEA AND VOMITING IN TERMINAL
CANCER PATIENTS
Nausea 50 - 60 Vomiting 30
3
MECHANISM OF NAUSEA AND VOMITING

• vomiting centre in reticular formation of
  medulla
• activated by stimuli from
• Chemoreceptor Trigger Zone (CTZ)
• area postrema, floor of the fourth ventricle
• outside blood-brain barrier (fenestrated
  venules)
• Upper GI tract pharynx
• Vestibular apparatus
• Higher cortical centres

4
Cortex
CTZ
GI
Vestibular
VOMITING CENTRE
5
CAUSES OF NAUSEA VOMITING
6
PRINCIPLES OF TREATING NAUSEA VOMITING

• Treat the cause, if possible and appropriate
• Environmental measures
• Antiemetic use
• anticipate need if possible (NB Children do not
  usually require prophylactic antiemetics when
  opioids started Ref Beardsmore et al 2002
  Palliative Care in Paediatric Oncology European
  J Cancer 38 p1900-1907)
• use adequate, regular doses
• aim at presumed receptor involved
• combinations if necessary
• anticipate need for alternate routes

7
H1
H1
CB1
Effector Organs
H1
CB1
M
5HT
H1
D
2
Muscarinic
Cannabinoid
Dopamine
Serotonin
Histamine
8
RELATIVE ANTIEMETIC RECEPTOR AFFINITIES
1250
9
EXAMPLES OF ANTIEMETIC USE

• haloperidol 0.5 - 1 mg po/sq/iv q6-12h
• prochlorperazine 5 - 20 mg po/pr/iv q4-8h
• CPZ 25 - 50 mg po/pr/iv q6-8h
• methotrimeprazine 5 - 10 mg po/sl/sq q4-8h
• metoclopramide 10 - 20 mg po/sq/pr q4-8h
• domperidone 10 mg po q4-8h
• scopolamine patch (Transderm-Vâ)
• metoclopramide 10 - 20 mg po/sq/pr q4-8h
• domperidone 10 mg po q4-8h

DOPAMINE ANTAGONISTS
ANTIMUSCARINIC
PROKINETIC
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EXAMPLES OF ANTIEMETIC USE

• dimenhydrinate 25 - 100 mg po/pr q4-8h(sq not
  recommended may cause irritation)
• promethazine 25 mg po/iv q4-6h (Not sq)
• meclizine 25 mg po q6-12h
• ondansetron 4 - 8 mg bid-tid po/sq/iv
• granisetron 0.5 1 mg po/sq OD - bid
• nabilone 1 2 mg po bid
• dronabinol 2.5 mg po bid, titrated up
• dexamethasone 2 - 4 mg po/sq/iv OD-qid
• lorazepam 0.5 - 1 mg po/sl q4-12h

H1 ANTAGONISTS
SEROTONIN ANTAGONISTS
CANNABINOIDS
MISCELLANEOUS
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Safety and Tolerability of 5HT3 Antagonists
Goodin S., Cunningham R. The Oncologist 2002
p424-436

• High specificity for 5HT3 receptors
  extrapyramidal reactions unlikely
• It has been suggested that the combination of a
  5HT3 antagonist with dexamethasone should be the
  standard antiemetic prophylaxis in all pediatric
  patients
• Granisetron well tolerated fever and headache
  most common adverse events

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Safety and Tolerability of 5HT3 Antagonists ctd
Goodin S., Cunningham R. The Oncologist 2002
p424-436

• May prolong QT interval
• 19 of patients given ondansetron in one study
• Seems less with granisetron
• risk of torsades de pointes
• use with caution when high dose methadone used,
  or in patients with arrhythmias or on other meds
  that might prolong QT

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Comparative Incidence of Adverse Effects
Granisetron (n542) vs. Ondansetron (n543)
Perez et al J Clin Oncol 199816754-760