test 2 Flashcards
poorly controlled pain may lead to __ pain states.
chronic
what does acute pain do to heart rate, PVR, ABP, myocardial contraction, and myocardial work?
increased
what does acute pain due to tidal volume, vital capacity, total lung capacity, etc?
decreased
what does acute pain do to gastric emptying, intestinal motility?
decreased, but increased sphincter tone
what does acute pain do to platelet aggregation and venostasis?
increased
what does acute pain do to immune function?
decreased
what does acute pain do to urinary sphincter tone?
increased
red flags
preop pain, fear of outcome, catastrophize pain, expect postop pain
what enzyme converts arachidonic acid into prostaglandins?
cyclooxygenase COX 1 and 2
what enzymes do nsaids work on?
cyclooxygenase 1 and 2 COX 1 and 2
What is the role of prostaglandins?
SENSITIZE nociceptors to pain, feel pain at a 4 instead of a 9
COX 1 is constituitive, what does that mean?
It is prolific in all body tissues, produced on a daily basis just like insulin
COX 2 is inducible, what does that mean?
Not produced on a daily basis, only when induced by inflammation, mediates pain, fever, carcinogenesis
What is COX 1 responsible for? and thus what would it do if we inhibited it?
responsible for platelet aggregation, gastic mucosal integrity, and renal function. If we inhibit it we have decreased platelet aggregations (aspirin), gastric irritation (ulcers) and renal microvascular constriction
When is celecoxib contraindicated?
hypersensitivity to sulfonamides (sulfa side chain) or ASA, caution in asthmatics d/t conversion of arachidonic acid into lukotrienes, causing bronchoconstriction
is toradol selective or non-selective COX inhibitor?
non-selective, therefore caution with coagulopathy, renal failure, ulcer, GI bleed, asthma, risk of postop bleeding
limit toradol use to __ days
5
your patient weighs >50 kg, how much ofirmev and how often?
4 grams TOTAL per day, divided into 1000mg q 6 or 650 q 4
your patient weighs <50 kg, how much ofirmev and how often?
max 75mg/kg/day, divided into 15mg/kg q 6 or 12.5 mg/kg q 4
when is ofirmev contraindicated?
liver failure
where is mu1 found?
supraspinal, in the periaquad
where is mu2 found?
spine and periphery
where are opioid receptors found in the spinal cord?
substantia gelatinosa Rexed lamina 2
how do opioids work pre and post synaptically?
pre = decrease adenylate cyclase and inhibit calcium channels post = increase potassium excretion leading to hyperpolarization
In time I can please everyone but susie sally
IV, tracheal, intercostal, caudal, paracervical, epidural, brachial, SAB/sciatic/femoral, subcutaneous
fentanyl metabolism, metabolites, excretion
liver metabolism by N-dealkylation, inactive metabolites, renal excretion
morphine metabolism, metabolites, excretion
hepatic glucuronidation, morphine-3 inactive / morphine-6 active (still asleep at 3 AM but active by 6AM), renal excretion
hydromorphone metabolism, metabolites, excretion
liver conjugation, inactive metabolite,
ketamine
NMDA antagonist, NMDA receptor at rest remains closed due to magnesium plug.
NMDA receptors are activated by
glutamate
activation of the a2 receptor (via clonidine or precedex) results in inhibition of ___
adenyl cyclase and decreased cAMP
alpha agonists inhibit __ and activate __
inhibit = presynaptic calcium channels activate = postsynaptic potassium channels equals hyperpolarized
where do alpha 2 agonists work in the brain?
locus coeruleus, posterior to the pons
who is a poor candidate for a alpha 2 agonist?
depleted catecholamines, elderly, immunosuppressed, young and weak
what’s the advantage of dexmedetomidine over clonidine?
7-10x more highly selective for alpha2 (1,620:1) vs. clonidine (220:1)
side effects of precedex and clonidine?
sedation, hypotension, bradycardia
dosing for precedex?
1mcg/kg bolus, infusion 0.2-0.7 mcg/kg/hr
PCA bolus dose for morphine
0.5 - 2.5 mg
PCA bolus dose for fentanyl
10-20 mcg
PCA bolus dose for hydromorphone
0.05 - 0.25 mg (1/10 of the morphine dose)
all PCA lockouts are basically
5-10 minutes
