Management of Common Symptoms in Cancer Pts Flashcards
State some common symptoms experienced by patients with cancer
- Pain (covered in separate deck)
- Nausea & vomiting
- Breathlessness
- Constipation
- Bowel & gastric outlet obstruction
- Anxiety & depression
- Signs of raised ICP (headaches, fits etc..)
- Confusion & delerium
- Fatigue
See Pain Assessment & Management FC for pain
Discuss the pathophysiology of/neurophysiology behind breathlessness
Mismatch between pts perceived need to breath and their ability to do so
State some examples of treatable causes of breathlessness and for each suggest possible management
Besides pharmacological/medical/surgical management, what else can you do to help someone with breathlessness?
*Helpful both as adjuncts to treatment when an underlying cause is identified and also in situations where no underlying cause identified
- Upright posture, lean forwards
- Loose clothing
- Air flow across face (fan or open window)
- Controlled expiration
- Ensure environment is calm & professionals appear confident
- Relaxation techniques
If there is no treatable cause for breathlessness and non-pharmacological management (e.g. posture, air flow etc…) aren’t working what else can you do?
Consider:
-
Opioids (low dose):
- Oramorph 1-2mg PO PRN
- Morphine 1-2mg SC PRN
- Morphine 5-10mg/24hr SCSD
-
Benzodiazepines (low dose):
- Lorazepam 0.5-1mg SL PRN
- Midazolam 2.5mg SC PRN
- Midazolam 5-10mg/24hr SCSD
*NOTE: if opioid naive prescribe prophylactic antiemetic & laxatvie
State some common causes of N&V (focusing on cancer pt but many causes also relevant to non-cancer pts)
Remind yourself of the 6 broad categories of things that can trigger the vomiting centre and cause nausea & vomiting (may hear them referred to as 6 broad N&V syndromes)
- Chemically mediated
- Vestibular nuclei
- Higher centres in brain/cortical (e.g. anxiety, pain, fear,
- Autonomic afferents/visceral & serosal (mostly from gut via vagus nerve but also from glossopharyngeal afferents)
- Reduced gastric motility
- Raised ICP
Where is the chemoreceptor trigger zone found?
Where is the vomiting centre found?
Both found in the medulla
CTZ= “area prostrema” on the floor of the fourth ventricle of the brain outside BBB
State which receptors are present at each of the following sites:
- Vestibular nucleus
- CTZ
- Vomiting Centre
- Visceral afferents from gut
- Vestibular nucleus: Achm & H1
- CTZ: D2 & 5HT3 & NK1
- Vomiting centre: Achm & H1 & 5HT2 & NK1
- Visceral afferents from gut: D2 & 5HT3
Which receptors does Haloperidol act on?
What situations is haloperidol a good antiemetic for?
- D2 receptors in CTZ
- Good for chemical (e.g. toxins in blood) causes such as:
- Uraemia
- Hypercalcaemia
- Opioid induced
Which receptors does metoclopramide & domperidone act on?
What situations are metoclopramide & domperidone good antiemetics for?
- Multiple mechanisms:
- Acts on D2 receptors in CTZ
- Acts on 5HT3 receptors involved in visceral afferents from gut
- Promotes gastric emptying by increasing tone at LOS, increasing peristalsis and decreasing tone of pylorus
- Good for causes related to decreased motility/stasis in GI tract e.g:
- Gastric stasis
- GORD
- Ileus
What’s the key difference, in regards to mechanism of action, between metoclopramide & domperidone?
Domperidone has limited ability to cross the blood-brain barrier and therefore acts primarily as a peripheral antagonist. Thus, in contrast to metoclopramide, domperidone rarely causes dystonic or extrapyramidal symptoms.
Which receptors does cyclizine act on?
What situation(s) is cyclizine a good antiemetic for?
- Acts on H1 receptors and Achm receptors in both the VC and VIII
- Useful for:
- Motion sickness
- Vertigo
- Bowel obstruction
- Raised ICP
Which receptors does ondansetron act on?
What situation(s) is ondansetron a good antiemetic for?
- Acts on 5HT3 receptors in CTZ and those involved in vagus afferents from gut
- Good for:
- Post operative nausea
- Radiotherapy induced
- Chemotherapy induced
Which receptors does hyoscine hydrobromide act on?
What situation(s) is hyoscine hydrobromide a good antiemetic for?
- Achm in the VC and VIII
- Good for:
- Motion sickness
Which receptors does aprepitant act on?
What situation(s) is aprepitant a good antiemetic for?
- NK1 receptors (substance P receptors) in CTZ & VC
- Good for:
- Toxin related e.g. chemotherapy related
Which receptors does levomepromazine act on?
What situation(s) is levomepromazine a good antiemetic for?
- Acts on many:
- D2 in CTZ
- 5HT2 in VC
- AChm in VC & VIII
- H1 in VC & VIII
- Good for:
- Treating nausea with multiple causes as is broad spectrum
When may dexamethasone be used to treat nausea & vomiting?
In situations where there is raised ICP as it is effective at reducing oedema & inflammation around tumours. May also be used in other situations such as hepatomegaly
State 4 antiemetics that would be good for chemically mediated vomiting (including chemotherapy)
- Haloperidol
- Ondansetron
- Aprepitant
- Levopromazine
State 2 antiemetics that would be good in gastric stasis
- Metoclopramide
- Domperidone
State which antiemetic should be used in raised ICP?
What else can be used to help?
- Cyclizine
- Dexamethasone, radiotherapy
*If have raised ICP would start on high dose dexamethasone. If can have RT would then decrease dose as start RT to lowest dose possible. If can’t have RT then still decrease dose to lowest possible dose
State 2 antiemetics that would be good for vestibular induced N&V
- Cyclizine
- Hyoscine hydrobromide
State 2 antiemetics that would be good for visceral/serosal induced N&V (not gastric stasis e.g. due to constipation, bowel obstruction)
- Cyclizine
- Levomepromazine
What medication would you use if you felt a pts N&V was due to anxiety?
Benzodiazepine e.g. Lorazepam
Summary of different mechanisms of actions of antiemetics
Discuss what route you should give antiemetics by
- Oral is first line
- However, if oral route not possible (e.g. vomiting, malabsorption or stasis/obstruction) then considered parenteral route (e.g. SC or IV if have access)
Most pts require more than 1 antiemetic; true or false?
False
- 60% only need 1 antiemetic
- ⅓ require a second
- If combining anti-emetics, combine ones with different actions
State some potential non-pharmacological treatments for N&V
- Avoiding smells
- Frequent small meals
- Anxiety management
- Acupuncture
Recap the management of delirium?
- Correcting any precipitating factors (e.g. infection, constipation, electrolyte imbalances)
- General advice: reorientation, safe mobilisaiton, normal sleep-wake cycle
- Medication:
- First line= Haloperidol
- Second line= benzodiazepines
State some signs & symptoms that may suggest someone constipated
- Not passing stool/reduced frequency
- Hard stool
- Stool difficult to pass
- Sense of incomplete evactuation
- Leakage of faecal fluid
- Faecal incontinence
- Colicky abdominal pain
- Abdo distension
- Flatulence
- N&V
- Anorexia
- Malaise
- Halitosis
- Urinary freqency
- Urinary retention
- Headache
State some potential causes of constipation- focusing on cancer pts
*HINT: try to think about different categories
Remind yourself of the different classes of laxative
- Osmotic
- Softeners
- Stimulants
- Bulk-forming
- Suppositories
How do osmotic laxatives work?
State some examples
- Increase osmotic pressure in lumen of bowel to draw fluid into the large bowel; this produces abdominal distention which stimulates peristalsis. Many osmotic laxatives, such as lactulose and macrogol, have stool-softening properties also.
- Examples:
- Macrogols
- Lactulose
- Phosphate & sodium citrate enemas
How do stimulant laxatives work?
State some examples
- Stimulate nerves (Senna stimulates colonic nerves; Bisacodyl & sodium picosulfate stimulate both colonic and rectal nerves) to cause peristalsis
- Examples:
- Senna
- Bisacodyl
- Sodium picosulfate
- Docusate (more of a softener but also has weak stimulating properties)
How do softener laxatives work?
State some examples
- Work by reducing the surface tension of the stools and allowing water and oil to enter the stool mass causing it to soften, which is then easier to pass
- Examples:
- Docusate
- Arachis oil
How do bulk forming laxatives work?
State some examples
- Act by retaining fluid within the stool and increasing faecal mass which in turn stimulates peristalsis
- Examples:
- Ispaghula husk
- Methylcellulose
- Sterculia
How do glycerine suppositories work for constipation?
- Glycerine suppositories work via numerous mechanisms:
- Lubrication: when the glycerine suppository melts it softens the stool and makes it easier to apss
- Hydration: glycerine suppository draws water into bowel. This can make the stool less hard and also aid rectal muscle contraction as distension occurs.
- Irritation: glycerine suppository irritates lining of the rectum causing rectal contractions
State some examples of laxatives with dual action/mix of two classes
- Sodium picosulfate (stimulant/softener)
- Docusate (softener/stimulant)
Summary of laxatives from ppt
Cause of malignant gastric/bowel obstruction can be mechanical or functional; explain the difference
- Mechanical: physical obstruction of the bowel be this a tumour in gut lumen or outside bowel wall compressing bowel lumen
- Functional: infiltration of the myenteric plexus +/- gut musculature impairing contraction of the bowel
Often a combination of both with a gradual onset.
State some common causes of malignant gastric outlet obstruction
- Advanced pancreatic cancer
- Advanced gastric cancer
State some common causes of malignant bowel obstruction
- Ovarian (affects 20-50%)
- Colorectal (affects 10-29%)
Discuss the management of malignant bowel obstruction
Multiple options available and will depend on patient’s disease, overall health and their wishes (e.g. are they for best supportive care):
- Surgical intervention: single site obstruction, high post-op morbidity & mortality & re-obstruction
- Endoscopic interventions:
- Endoscopic stenting
- Venting gastrostomy: to decompress
- Medical management:
- Initially rest bowel to see if it will resolve; make pt NBM initially then on days 2-3 you can re-evaluate and may be allowed sips of fluids, then increase..
- IV fluids (if not drinking. Reassess need regularly)
- NG tube insertion if large volume vomiting
- Correct electrolyte imbalances
- Medications:
- Opioids & antispasmodics (e.g. hyoscine butylbromide) for pain
- Octreotide to reduce intestinal secretions
- Dexamethasone to reduce tumour oedema
-
Antiemetic
- Cyclizine in complete obstruction
- Metoclopramide may help in partial/functional obstruction if patient is able to pass flatulence
If pt has inoperable malignant bowel obstruction, aim is to reduce symptoms (pain, N&V etc…). Often use syringe driver to deliver medications. Prognosis may be weeks- months.
Discuss the management of malignant gastric outlet obstruction
Multiple options dependent on disease & pt:
- Surgical options:
- Resection
- Gastrojejunostomy
- Endoscopic stenting
- NJ or GJ tube
What 3 cancers are the most common to metastasise to brain?
Where, in brain, are metastases most common?
- Lung, breast & melanoma
- Frontal or temporal lobes most common
