Surgery Pharm Flashcards
1
Q
What are the adverse outcomes of undertx perioperative pain?
A
- thromboembolic complications
- pulmonary complications
- increase length of hospitalization
- hospital readmission for further pain management
- needless suffering
- impairment of quality of life
- development of chronic pain
2
Q
Adverse outcomes of perioperative pain management?
A
- respiratory depression
- brain injury
- neuro injury
- sedation
- circulatory depression
- N/V
- pruritius
- urinary retention
- impairment of bowel fxn
- sleep disruption
3
Q
What must you always document regarding pt and pain throughout operation?
A
- pain intensity
- effects of pain therapy
- SEs caused by therapy
4
Q
What are factors to consider when deciding pain management for pt?
A
- type of surgery
- expected severity of postop pain
- underlying medical conditions: CVD, pulm, allergies, renal or liver failure
- risk-benefit ratio for available techniques
- pt’s preference
- pt’s previous experience w/ pain
5
Q
Preop prep of pt?
A
- H and P
- post op pain control plan
6
Q
What should you do preop w/ pt?
A
- adjust or continue meds that may provoke a withrawal syndrome
- tx to reduce preexisting pain and anxiety: consider initiaion of post op pain management
- premeds b/f surgery
- pt and family education:
addiction
adverse effects of meds
optimal use of pt-controlled analgesia
7
Q
Periop techniques for pain management?
A
- central regional opioid analgesia
- pt controlled analgesia w/ systemic opioids
- peripheral regional analgesia:
intercostal blocks
plexus blocks
local anesthetic infiltration of incisions
8
Q
What is central regional opioid analgesia? Benefits and risks?
A
- epidural or intrathecal admin of analgesia - epidural: injection outside of the dura
intrathecal: aka spinal anesthesia - injection through dura directly into CSF - benefits: improved pain relief when preincisional epidural or intrathecal morphine is admin compared w/ po, IV, or IM morphine
- risks: increased pruritus and urinary retention in post op epidural anesthesia compared to IM morphine
9
Q
Amt of intrathetcal opioids admin?
A
- intrathecal morphine (0.1-0.2 mg) or fentanyl (10-20 mcg)
- a single dose of intrathecal opioid (morphine) can provide pain relief for up to 18-24 hrs post op: onset of action: 45 min
- fentanyl provides pain relief for 1-2 hrs: onset of action 5-10 min
10
Q
What is pt controlled analgesia? Benefits?
A
- for moderate to severe post op pain
- benefits: decreased delay in pt access to pain med, decreased likelihood of overdose
- pump usually d/c when able to take oral meds
- morphine, hydromorphone and fentanyl can be given via PCA
- fentanyl is less desirable due to short DOA: may be useful if morphine allergy, easier to use in hepatic or renal insufficiency than others
- improved pain scores comparing IV PCA morphine to intramuscular morphine
- studies show that having IV PCA pump w/ a background infusion of morphine vs PCA pump w/o background infusion:
more analgesic used, findings equivocal regarding pain relief, nausea, and vomiting, pruritus, sedation
11
Q
What are multimodal techniques for pain management?
A
- using 2 or more drugs that act by different mechanisms for providing analgesia
- systemic meds: opioids+NSAIDs
- central and regional meds: epidural and local anesthetics (ex: fentanyl _ bupivocaine admin via epidural): better pain control but more muscle weakness and pruritus noted
12
Q
Benefits of systemic analgesics?
A
- improved pain scores and reduced analgesic use when given IV morphine + ketorolac compared to IV morphine alone
- ketorolac along w/ PCA opioid admin is more effective at decreasing pain vs COX-2 or nonselective NSAIDs
- lower pain scores when adding gabapentin or pregabalin to IV opioids
- unless CI pts should receive schedules regimen of NSAIDs, COXIBs or acetaminophen
13
Q
What are peripheral regional techniques of pain management?
A
- peripheral nerve blocks, intraarticular blocks, and infiltration of incisions
- preop nerve blocks are effective at reducing postop pain and decrease the need for opioid use (post blocks aren’t helpful)
- preop infiltration of the incision w/ local anesthetic (ex. Bupivicaine) decreases postop pain scores
14
Q
What pts are at risk for inadequate pain control?
A
- peds
- geriatrics
- critically ill
- cognitively impaired
- others who may have difficulty communicating
15
Q
What is the role of the PA in the management of the post surgical pt?
A
- know the pt’s hx
- procedure performed and any complications
- type of anesthesia used for the case
- duration of case and if that is normal for procedure mentioned
- what has pt received so far, did it work, any adverse rxns and what other modalities are in play? (epidural pain management, nerve block)
- adjustment of opioid dose and/or initiation of acetaminophen, NSAIDs or gababpentin may be needed
16
Q
Diff types of opioids?
A
- *morphine,
- *hydromorphone (dilaudid)
- *fentanyl
- meperidine
- 3 most commonly used for post op IV pain management
17
Q
Diff routes of opioid admin?
A
- most widely used med for tx of postop pain
- bolus injections are often used: given this way they fail to provide steady state of drug
- continuous infusions: may be dangerous due to potential for drug build up and cause respiratory depression, must be given in a highly supervised enviro
- pt controlled analgesia
18
Q
Metabolism of opioids?
A
- all opioids are hepatically metabolized to active and inactive metabolites which are eliminated in urine
- pts w/ severe liver disease will need dosage adjustments
19
Q
Morphine: type, onset? Elimination half life? Duration of action? Admin? Excretion? CI?
A
- prototypical opioid
- onset of analgesia is rapid
- peak in 1-2 hrs
- elim half life: 2-3 hrs
- analgesic duration of action: 4-5 hrs
- IV 1-3 mg q 5min until pain relief or adverse effects like sedation, hypotension, respiratory depression, and hypoxemia
- active metabolites eliminated renally
- in renal insufficiency active metabolites may accumulate and cause neurotoxicities: myoclonus, confusion, coma and death
- relatively CI in severe renal disease
- erratic absorption from GI tract
20
Q
Hydromorphone (dilaudid):
Onset, half life?
A
- more rapid onset of analgesia reaching peak w/in 30 min
- half life: 2.4 hrs
- approx 4-6x more potent than morphine
- 0.2-1 mg q 2-3 hrs
21
Q
What is fentanyl?
How powerful?
When is it preferred?
A
- synthetic derivative of morphine
- approx 100x more potent than morphine
more lipid soluble than morphine:
more rapid onset of action, improved penetration of blood brain barrier, shorter half life, eliminaton half life is 2-4 hrs - doesn’t release histamine and may be preferred in presence of hemodynamic instability or bronchospasm
22
Q
Fentanyl:
amt admin depending on pain?
A
- moderate pain: 25-50 mcg IV q 5 min up to max dose
- moderate to severe pain: 50-100 mcg q 2-5 min until pain relief
- IV infusion for pain control in mechanically ventilated pts:
0. 7-10 mcg/kg/hr, admin over 5 days may lead to deposition of drug in adipose tissue and prolonged sedation
23
Q
Meperidine:
Indication
CI
SEs
A
- indicated for short term management of acute pain
- CI in pts on MAOIs
- lower seizure threshold
- has dysphoric effect
- not as effective as other drugs
- slower rate of metabolism in elderly or if liver or renal failure
- not usef for PCA pumps b/c of risk for accumulation of active metabolite
24
Q
SEs of opioids?
A
- somnolence
- depression of brainstem control of respiratory drive
- hypotension
- urinary retention
- N/V
- slowing of GI transit: constipation, ileus
- histamine release: MC after morphine - flushing, tachycardia, hypotension, pruritus, bronchospasm
25
How can you transition from IV to oral opioids?
- switch from IV to oral once pt can tolerate PO
- calculate 24 hr opioid consumption to determine coverage needed:
consult equianalgesic charts
- PO - analgesic effects take 30-60 min
- switch to one of the following: oxycodone, hydrocodone, hydromorphone, morphine: ex 40 mg of IV morphine given in 24 hrs would reqr 20 mg oxycodone q 4 hrs or 5 mg of hydromorpone q 4 hrs
26
What are the oral opioids used?
oxycodone (oxycontin) (roxicodone) -
- oxycodone/acetaminophen (percocet)*
- oxycodone/ibuprofen (combunox)
- schedule II
hydrocodone (hysingla ER) (Zohydro ER):
- hydrocodone/acetaminophen (lortab) (Vicodin) (norco)*
- hydrocodone/ibuprofen (vicoprofen)
- schedule III
hydromorphone (diluadid):
schedule II
morphine (Avinza) (duramorph) (kadian) (MS contin):
schedule II
* MC used po pain meds post surgery
27
Duration of action of diff opioids?
- short acting: fentanyl
- moderate acting: DOA 4-6 hrs
morphine, codeine, hydromorphone, oxycodone
- long acting: methadone, long acting morphine preparations
28
What opioids are safe in pts w/ impaired renal fxn?
- hydromorphone and oxycodone have inactive metabolites: safer than morphine for use in renal impairment
- fentanyl: safer than morphine for use in renal impairment
29
Opioid reversal agent?
- naloxone (narcan)
- reversal of respiratory depression w/ therapeutic opioid doses:
IV, IM, Subq, endotracheally:
initial 0.04-0.4 mg:
may repeat until desired response achieved. If desired response isn't observed after 0.8 mg total, consider other causes of respiratory depression
30
What are non-opioid adjunctive meds used?
- NSAIDs
- ketamine
- lidocaine
- magnesium
- IV acetaminophen
31
Use of NSAIDs?
- can reduce dose of opioid reqd
- caution w/ kidney impairment
nonselective:
-IV formulations: ketorolac and ibuprofen
-ketorolac reduces opioid constipation by 25-45%
-ketorolac dose 15-30 mg IV over 15 sec
- then dose q 6 hrs x 3-5 days
selective:
no IV formulation available, sometimes just a single dose might suffice
32
Dosing of oral NSAIDs?-
- nonselective PO or PR:
ibuprofen 400mg q 4-6 hrs
diclofenac 50 mg q8hrs
ketoprofen 50 mg qid
-selective:
celecoxib (celebrex): 400 mg po x 1 then 12 hrs later start 200 mg po BID
33
What is ketamine? Use?
- NMDA receptor inhibitor
- use limited due to hallucinations
- reduces hyperalgesia and opioid tolerance
34
Use of acetaminophen? CI?
- oral or rectal 1st line then can give IV: 325 mg-1000 mg PO or PR q 4-6 hrs/max dose 4 g
- may be given in addition to NSAIDs
- CI in hepatic failure
35
use of lidocaine?
- class I antiarrhythmic
- IV infusion intra-op or post-op for control of pain
- 1.5-2 mg/kg bolus then 1.5-3mg/kg/hr
- most effective for analgesia following major abdominal surgery
36
Use of Mg sulfate?
- can reduce opioid requirements
- NMDA receptor antagonist
- bolus or infusion
- not routinely used at this time despite many studies to show its effectiveness
