Palliative care: N/V, obstruction, SOB, cord compression Flashcards
What 4 body systems can stimulate the vomiting centre?
Cortex, chemoreceptor trigger zone, vestibular system, gut.
What stimuli activate the cortex to cause vomiting? What drug(s) can target this?
Raised ICP (eg. tumour, bleed); anxiety; anticipatory. Dexamethasone - reduce oedema.
What stimuli activate the chemoreceptor trigger zone to cause vomiting? What drug(s) can target this?
Drugs; metabolic disruption.
Ondansetron (5HT3 antag); haloperidol (D2 antag); prochlorperazine (D2 antag, less in pall care due to SE)
What stimuli activate the vestibular system to cause vomiting? What drug(s) can target this?
Motion; labyrinthitis; acoustic neuroma.
Cyclizine - histamine R antag.
What stimuli activate the gut to cause vomiting? What drug(s) can target this?
Inflammation (infection/toxin/poison); mechanical (obstruction; distention; slow empty)
Domperidone & metoclopramide - D2 in gut for motility (don’t cross BBB)
What drugs can act directly on the vomiting centre?
Cyclizine (histamine R) and hyoscine butylbromide (muscarnic R)
In the setting of malignant bowel obstruction, what are 4 things to consider in a partil obstruction?
Can have oral intake and fluids; consider metoclopramide to push through; don’t use hyoscine butylbromide (buscopan).
In the setting of malignant bowel obstruction, what are 3 drugs to consider in a complete obstruction?
Hyoscine butylbromide will reduce secretions and spasms to reduce colic.
Dexamathasone and octreotide can reduce gut blood flow and secretions.
What are 3 kinds of interventions to consider in managing the symptom of dyspnoea in palliative care?
Non-pharm: ventilation, fans, mobilisation, posture, oxygen.
Pharm for a cause (eg. antibiotic, diuresis, bronchodilator)
Pharm for symptom: opioids to reduce resp centre sensitivty; benzos as anxiolytic.
What are 4 cancers which are common and spread to bone? What % of cord compressions does each account for?
Prostate, breast, lung and kidney. 15% each.
What are 3 less common cancers which cause cord compressions?
Myeloma, lymphoma and unknown primaries.
Which part of the spinal cord is most commonly affected by compression? Consider why?
Thoracic > lumbar > cervical. Most thoracic segments + cord ends at L2 and get cauda equina below (LMN)
What are the symptoms of a cord compression? Timecourse?
Local pain (back) first; focal neurology - weakness, decreased sensation, incontinence. Hours to days - like compartment syndrome from veins blocked.
How should a suspected cord compression be managed?
High dose dexamethosone immediately, MRI to confirm diagnosis. Then surgery or radiotherapy, urgently.
