W22 Pain in Palliative Care Flashcards
What is Palliative Medicine?
- Reducing the severity of; denoting the
alleviation of symptoms without curing the
underlying disease’ - Anything used to alleviate pain, anxiety, etc. Alleviate (disease) without curing it.
Features/Aims of palliative care?
- Provides relief from pain and other distressing symptoms;
- Affirms life and regards dying as a normal process;
- Intends neither to hasten or postpone death;
- Integrates the psychological and
spiritual aspects of patient care; - Offers a support system to help
patients live as actively as possible until death; - Offers a support system to help the family cope during patient’s illness and their own bereavement;
Pain:
Physical/biological factors:
Psychosocial:
Psychological:
Other factors:
Nociceptive, injury, trauma,
infection, illness, cancer, nerve damage
Relationships, Work/employment, Social Networks, Isolation
Impact on: Mood, concentration,
sleep, negative thoughts, irritability,
helplessness, Anxiety and depression
Personality aspects, fears, beliefs, coping
skills, level of trust
Drug dependence / abuse, Financial difficulties, Cultural barriers, Litigation
Language barriers, Lack of health
insurance
Appropriate Treatment of Pain
What should be asked in hx taking?
- history of pain
- the type of pain
- pain intensity
- aetiology
Useful questions
* Tell me about the pain.
* What makes it better?
* What has/hasn’t helped in the past?
* Does the current medication relieve the pain?
* What problems/side-effects have you had with your pain medication to date?
What are the Common Causes of Cancer Pain?
Direct effects:
* bone destruction
* hepatomegaly
* infiltration of pleura or peritoneum
Effects of therapy:
* phantom limb
* post-mastectomy
* post-radiation
Non-malignant causes:
* osteoporosis
* osteoarthritis
* diabetic neuropathy
What are the options for analgesia?
Step 1: Non-opiod analgesics? (2)
Paracetamol
* blocks PG synthesis in CNS
* no significant anti-inflammatory action
* caution in hepatic dysfunction
Non-steroidals (NSAIDs)
* inhibit PG synthesis at COX-1 and COX-2
* peripheral rather than central action
* limited by toxicity
* can also be used as adjuvant at any stage
STEP 2: WEAK OPIOIDS
What are examples? (3)
- Single active ingredient best
- Need to give adequate doses – dependence may occur
Codeine - 10% converted to morphine
- large doses may cause excitement
Dihydrocodeine - semi-synthetic
- potency between codeine and morphine
- may cause histamine release
Tramadol - advantages negligible
- use shouldn’t delay appropriate increase to step 3
STEP 3: STRONG OPIOIDS:
What is the drug of choice?
Morphine
-drug of choice
-affects initial perception and emotional response to pain
-should not cause euphoria in severe pain
Initiation of Morphine?
Starting doses of Morphine?
Initiation
-dose based on symptoms, previous treatment and patient characteristics
-usually initiate with normal-release (4 hourly) but can use m/r
- ‘rescue doses’ of 1/10th – 1/6th of 24h dose
-titrate against pain until relief satisfactory
Starting doses:
- If patient opioid naïve: 20-30mg daily in divided doses
- If switched from regular weak opioid: 40-60mg daily in divided doses
* Regular review of rescue doses and calculation of m/r dose required
MORPHINE- Maintenance
- Use m/r preps when stable
- 12 hourly or 24 hourly preparations available
- Use previous 24 hours as guide to dose
- Provide ‘rescue doses’
Example of switch to m/r morphine:
- Patient prescribed 30mg 4 hourly (6 doses)
- Also prescribed 1/6th of total daily dose for use every 2-4 hours when needed
- Over a few days it is noted that the patient has taken all regular doses and is using 2 rescue doses a day
- For convenience, morphine is now switched to 12 hourly m/r preparation with new rescue dose calculation
So 12 hourly m/r dose is 120mg BD
New rescue dose is 1/10 to 1/6 of TDD
= 24-40mg 2-4 hourly
What is Oxycodone?
- Alternative strong opioid
- Available in normal release and m/r
formulations - Useful if patient gains relief but cannot
tolerate morphine - Oral dose equivalent to about 2/3rds that of morphine
What are SOME ALTERNATIVES?
Fentanyl (available as patches)
Buprenorphine
Hydromorphone
Pethidine
Methadone (long half-life)
Ketamine
What are the ADVERSE EFFECTS OF
OPIOIDS?
- Nausea and vomiting
-occurs in 30-60% of patients
-direct stimulus of CTZ
- may need anti-emetics - Constipation
- due to effect in GI tract and spinal cord
- prophylaxis required
CHOICE OF ANTI-EMETIC
Should be based on the which most
likely mechanisms? (3)
- Direct or central
-GI tract or vomiting centre - cyclizine - Chemical
-via CTZ - haloperidol - Mechanical
-delayed gastric emptying - metoclopramide
