Pain Management Flashcards
What are the two major types of pain?
Nociceptive
Neuropathic
What is nociceptive pain?
NORMAL
Free nerve endings activated
What is neuropathic pain?
ABNORMAL processing of stimuli from PNS or CNS that serves no useful purpose
How does paracetamol treat pain
Inhibits prostaglandin synthesis centrally
Which two organs should be monitored when giving paracetamol?
Kidneys and liver
How do NSAIDs work
Inhibit synthesis of prostaglandins (good anti-inflammatory agents). This is achieved by inhibiting the COX-1/2 pathways
when do you NOT use NSAIDS
ACTIVE peptic ulceration, hypersensitivity to NSAIDs
what are some of the benefits of using COX-2 inhibitors
Less GIT toxicity than non-selective NSAIDs
what are some of the disadvantages associated with COX-2 NSAIDs as if you inhibit COX-1, you inhibit platelet aggreg.
Increased CVS risk (MI and Stroke)
What are some of the adverse effects of NSAIDs
Bronchoconstriction
Bleeding
Dyspepsia and Peptic Ulceration
Fluid retention
Hypersensitivity
Hepatotoxicity
Nephropathy and ARF
Are COX-2 inhibitors suitable for patients with IHD or CVD?
No
What are some of the CNS effects of morphine?
Euphoria, sedation, analgesia
how do opioids work?
Histamine is released resulting in vasodilation, itching and bronchoconstriction
how do you administer morphine
10mg 4 hourly for 24 hours, increase by 30-50%
what are some of the adverse side effects of morphine
nausea, sedation, constipation, resp depression
which population groups should take morphine with caution
Renal & Hep impairment, Preggers, Neonates, lactation, elderly, COPD & acute asthma (decr. pulmonary reserve)
What type of opioid is tramadol?
Moderate to severe pain
u receptor agonist
Prevents reuptake of serotonin and noradrenaline
Can get Serotonin Syndrome (when combined to SSRI, MAOIs)
Metabolism induced by carbamazepine
Less severe side effects
What is one disadvantage of tramadol
it lowers seizure threshold
What is a huge pro of tramadol
Synergistic analgesic with paracetamol
codeine phosphate properties
Mild to moderate pain
Weak opioid
Adverse effects as with morphine
Codeine Phosphate CYP2D6 variant
Slow metaboliser: poor analgesic effect but constipation
Rapid metaboliser: Resp depression, coma and death
What is chronic pain?
4-6 week duration
Somatic chronic pain
Arthritis, fibromyalgia, lower back pain
Visceral chronic pain
pleurisy, cancer pain
Neuropathic pain
Diabetic neuropathy
Trigeminal neuralgia
Post-herpetic neuralgia
Peripheral neuropathy
examples of adjuvant therapy
TCA: amitriptyline
analgesic
anxiolytic
antidepressant
sedative
start at 10-25mg nocte (good if pain associated with sleep and anxiety disorder)
Anticonvulsants:
Carbamazepine, valproate, gabapentin
Good for neuropathic pain
can be used with TCA
