Pain Management/Analgesics Flashcards
definition of PAIN
an UNPLEASANT SENSORY & EMOTIONAL EXPERIENCE that is often associated with ACTUAL or POTENTIAL HARM
- it is SUBJECTIVE
difference between ACUTE PAIN vs. CHRONIC PAIN
ACUTE PAIN;
- based more on SUDDEN ONSET
- typical CLEAR CAUSE (ex. post-op, injury)
- is often more TEMPORARY
- < 3 - 6 months
CHRONIC PAIN:
- more PERSISTENT
- can have an UNCLEAR CAUSE
- > 3 - 6 months
describe the GATE THEORY
- is the MOST COMMON THEORY based about PAIN TRANSMISSION and PAIN RELIEF
what are the MAIN STEPS of the GATE THEORY?
- Releases SUBSTANCES from injured cells (ex. bradykinin, histamine, prostaglandins…)
- Activation of ACTION POTENTIALS towards the NOCICEPTORS
- Pain signals go to the DORSAL HORN *considered the GATE
what is the GATE responsible for?
- important to help REGULATE the FLOW of sensory nerve impulses
- helps to regulate the NUMBER & INTENSITY of these action potentials
somatic pain
pain within the skeletal muscles, ligaments, or joints
visceral pain
pain located in the ORGANS, SMOOTH MUSCLES
referred pain
pain felt in areas not directly injured
*ex. cholecystitis - referred pain in the shoulders or back
what is the WHO THREE-STEP ANALGESIC LADDER?
- THREE-STEP ANALGESIC LADDER (WHO):
- STEP ONE: USE OF NONOPIOIDS
- STEP TWO: USE OF OPIOIDS
- with or without nonopioids
- with or without adjuvants
- STEP THREE: USE OF OPIOIDS *indicated for moderate to severe pain
what are the DRUG CLASSES for PAIN MANAGEMENT?
- NONOPIOID ANALGESICS
- OPIOIDS
(AGONISTS)
(AGONISTS-ANTAGONISTS)
(ANTAGONISTS) - ADJUVANTS
definition of AGONISTS
- binds to an OPIOID PAIN RECEPTOR in the brain - allows to block pain signal
- REDUCTION OF PAIN
definition of AGONISTS-ANTAGONISTS / PARTIAL/MIXED AGONIST
- binds to a PAIN RECEPTOR
- causes WEAKER PAIN RESPONSE vs. FULL AGONIST
definition of ANTAGONISTS
- binds to a PAIN RECEPTOR
- does NOT REDUCE PAIN RECEPTORS
- often is a COMPETITIVE ANTAGONIST
what are some potential ADVERSE EFFECTS of opioids?
- constipation
- N & V
- sedation / mental clouding
- respiratory depression
- subacute overdose
describe PCA, and PCA by proxy
PCA - known as PATIENT-CONTROLLED ANALGESIA; self-medication through pump
- often used to admin. MORPHINE & HYDROMORPHONE
PCA PROXY - when family members admin. medication instead - can lead to death due to overdosing
breakthrough pain
- seen in LONG-TERM USE / LONG-ACTING OPIOIDS
- drug begins to metabolize & become eliminated from the body
- needs the use of PRN MEDS to aid in management
opioid tolerance
patient has ADAPTED to opioid medications due to greater exposure - changed DRUG RECEPTORS, effects of the drug is reduced
- can cause WITHDRAWAL SYNDROME/symptoms
codeine sulfate
- agonist
- sched II med
- only med with a CEILING EFFECT
- combined with acetomino. > sched III
- often used as ANTITUSSIVE drug
fentanyl
- very POTENT opioid, sched II
- has many forms
- has effective TRANSFERMAL approach
- 0.1mg (fent.) = 10 mg morphine
hydromorphone
- sched II
- 1 mg (IV/IM) = 7 mg morphine
- **exalgo - Xcannot crush, extended-release
meperdine
- sched II
- CAUTION - elderly, kidney issues
- **NORMEPERIDINE - active toxic metabolite = can cause SEIZURES
- not good for LONG-TERM USE
methadone hydrochloride
- sched II
- often used for detox treatment
- long half-life - can cause overdose
- cardiac dys.
morphine sulfate
often used for SEVERE PAIN and is the drug prototype for all opioid drugs
- lots of forms
oxycodone
- related and similar activity as morphine
- combined often with acetamino. and aspirin
naloxone hydrochloride (NARCAN)
- is a **PURE OPIOID ANTAGONIST
- used primarily to REVERSE OPIOID-INDUCED RESPIRATORY DEPRESSION
mechanism of action: acetaminophen
- similar to SALICYLATES
- blocks PAIN IMPULSES by inhibition of PROSTAGLANDIN SYNTHESIS
dosage of acetamino.
around 3000 mg/day
- 2000 mg/day for older adults/liver disease
