Nausea and Vomiting Flashcards
what are the 6 nausea and vomiting syndromes?
- reduced gastric motility
- chemically mediated
- visceral/serosal
- raised intra-cranial pressure
- vestibular
- cortical
how is reduced gastric motility related to nausea and vomiting?
- related to serotonin (5HT4) and dopamine (D2) receptors
- may be opioid related
what is the cause of chemically mediated nausea?
- hypercalcaemia
- opioids
- chemotherapy
what is the cause of visceral/serosal nausea?
constipation
what is the cause of raised intra-cranial pressure related nausea?
cerebral metastases
what is the cause of vestibular nausea?
- related to activation of acetylcholine and histamine (H1) receptors
- can be opioid related
- can be motion related, or due to base of skull tumours
what is the cause of cortical nausea and vomiting?
- anxiety
- pain
- fear
- anticipatory nausea
related to GABA and histamine (H1) receptors in the cerebral cortex
what types of anti-emetics are used in reduced gastric motility related nausea?
pro-kinetic agents
name examples of anti-emetics given when there is reduced gastric motility
- metoclopramide
- domperidone
when is metoclopramide contra-indicated?
when pro-kinesis may negatively affect the GI tract
* complete bowel obstruction
* GI perforation
* following GI surgery
how is chemically mediated nausea managed?
- correct chemical disturbance
- anti-emetic
name example anti-emetics prescribed in chemically mediated nausea
- ondansetron
- haloperidol
- levomepromazine
name example anti-emetics prescribed in visceral/serosal causes of nausea
- cyclizine
- levomepromazine
how is raised intra-cranial pressure associated nausea managed?
- cyclizine
- dexamethasone
- radiotherapy
how is vestibular associated nausea managed?
cyclizine
