Exam 4 GI + Pain Flashcards
(92 cards)
Nociceptive pain
Nerve receptor stimulation following tissue injury, disease or inflammation
Neuropathic pain
Abnormal signal processes in the CNS, perceived as burning, tingling, shooting
Neurotransmitters involved in pain
Prostaglandins, histamine, bradykinin, serotonin
Main inhibitory neurotransmitters
Serotonin and norepinephrine
Acetaminophen
Prostaglandin inhibitor in CNS and COX3
No anti-inflammatory, platelet or GI effects
Decreases opioid requirements by 30%
Aspirin
Effective as APAP
Very effective in pain associated with inflammation
GI side effects
Irreversible inactivation of COX1 and COX2
COX1 inhibition
Leads to decreased blood flow to kidney, GI tract tissues and decreases platelet aggregation
COX2 inhibition
Decreases inflammation
Misoprostol (Cytotec)
Can decrease NSAID induced bleeding
Synthetic prostaglandin E analog parent drug rapidly de-esterified to misoprostol acid and replaces protective prostaglandins
Inhibits gastic acid secretions and protects gastric mucosa
Pregnancy category X
SE: diarrhea, abdominal pain, HA
Ketorolac (Toradol)
First parenteral NSAID available
Use limited to <5 day due to SE profile
Effects of opioids
Analgesia, respiratory depression, sedation, confusion, N/V, pruritus, miosis, constipation, urinary retention
Opioid DOC in renal or liver failure
Fentanyl
Fentanyl forms
Injectable, buccal, long acting transdermal patch (duration of 72 hours)
Causes less histamine release than other opioids
Tramadol
Centrally acting weak mu receptor agonist; also inhibits NE reuptake and increases serotonin release
Less respiratory depression
May increase risk of seizures
Methadone
Used to treat opioid substance abuse
Mu receptor agonist and NMDA receptor antagonist
8-12 hours duration if used chronically
Cheap and good for refractory pain
Naloxone
pure opioid antagonists
Used for opioid induced respiratory depression
Lasts 45 minutes
SE: tachycardia, htn, V Fib, cardiac arrest, seizures
Opioid treatments of constipation
Methylnaltrexone or naloxegel
Mu antagonism in gut only
Withdrawal symptoms of opioid use
Tremors, sweating, fever, flu like symptoms, increased RR, perspiration, lacrimation, mydriasis, anorexia
Co-analgesics
Antidepressents, anticonvulsants, sodium channel blockers, antispasmodics, antispastics
Antidepressants for pain relief
TCAs and SNRI
Good for neuropathic pain
Anticonvulsants for pain relief
Gabapentin, pregabalin, carbamezapine usually
Decrease activation of second order neurons responsible for pain transmission
Good for neuropathic pain
Sodium channel blockers
Act as local anesthetics
Block Na channels, slowing pain transmission and lowering firing threshold of second order neurons
Topical lidocaine patches indicated for postherpetic neuralgia
Ketamine
NMDA antagonist
Lower doses for analgesia, higher doses for anesthesia
Decreases sensitivity to pain impulses
SE: vivid dreams, sedation, delirium, hallucinations
Cyclobenzapine
Antispasmodic skeletal muscle relaxant
Mostly used for lower back pain
Has anticholinergic SE