Week 10 Flashcards
what are some impacts of nausea and vomiting (8)
- dehydration & hypovolemia
- electrolyte abnormalities
- esophageal tears/bleeds (d/t straining w retching)
- decreased QOL
- weight loss/anorexia
- psychological distress
- refusal of beneficial therapy (ex. chemo)
- risk of aspiration pneumonia (d/t weakness, decreased gag reflex at end of life)
where does the emetic center receive info from (4)
- the chemoreceptor trigger zone (CTZ)
- the vestibular system
- the CNS
- the vagal and enteric nervous system = GI system
chemical disturbances impact what area?
- the CTZ
what receptors are activated in the CTZ by chemical disturbances (2)
- dopamine (D2)
- serotonin (5HT3)
what are some examples of stimuli that trigger NV at the CTZ (3)
- opioids
- electrolyte disorders
- hypercalcemia
what are 3 meds of choice if the receptor impacted in the CTZ is dopamine (3)
- stemitil
- haldol
- maxeran (low dose)
what are 2 meds of choice if the receptor impacted in the CTZ is serotonin
- maxeran (high dose)
- ondansetron
what area is impacted in NV center by visceral disturbances
- abdominal organs/gut
what receptors are activated w visceral disturbances (2)
- dopamine (D2)
- serotonin (5HT3)
meds = same as CTZ
what area is affected in NV center by vestibular disturbances
- vestibular nuclei
what receptors are activated in vestibular nuclei (2)
- histamine (H1)
- muscarinic (M)
NV caused by vestibular disturbances may be seen in pts with…
acoustic neuroma (ear tumour)
what are 2 meds of choice for histamine receptors
- gravol
- phenergan
what is a med of choice if the receptor if muscarinic
- scopolamine
what area is affected w NV caused by CNS disturbances
cerebral cortex
what receptor is activated in the cerebral cortex w CNS disturbances
- histamine (H1)
* same meds as before*
what are the 2 principles of therapy for NV
- identify the underlying cause
- antiemetic use
what are some principles regarding antiemetic therapy (5)
- anticipate need
- use adequate, regular doses
- aim at receptor involved
- combos if necessary
- anticipate need for alternate routes (ex. enviro measures)
what are some environmental measures that can help w NV (7)
- limit exposure to food smells
- bland foods
- small, freq meals/snacks
- good oral hygiene
- fresh air
- calming enviro
- sitting upright post meal
what should you consider if the NV continues
- reassess
- all causes identified?
- correct med used?
- adequate dosing?
true or false: chemical disturbances affect emetic receptors in the CTZ
true
true or false: there are muscarinic receptors in the CTZ
false
T or F: the med Stemitil blocks emetic stimuli that trigger dopamine receptors
true
T or F: the med Ondansetron blocks emetic stimuli that trigger serotonin receptors
T
T or F: the med Phenergan blocks emetic stimuli that trigger histamine receptors
T
T or F: there are serotonin receptors in the inner ear
false
T or F: there are histamine receptors in the abdominal oragans and gut
False
T or F: there are histamine receptors in the cerebral cortex
true
what is CACS
- cancer anorexia cachexia syndrome
- cluster of symptoms
what symptoms are included w CACS (5)
- cachexia
- anorexia
- early satiety
- chronic nausea
- asthenia
what is anorexia
- “without appetite”
- not a willful choice, simply no desire to eat at all