N926 Pharmacology Final Exam Flashcards
MAC of Desflurane
6%
VP of Desflurane
669
BGC of Desflurane
0.42
Oil Gas of Desflurane
19
MOA of Desflurane
Unknown
MAC of Isoflurane
1.2%
VP of Isoflurane
238
BGC of Isoflurane
1.4
Oil Gas of Isoflurane
91
MOA of Isoflurane
Uknown
MAC of Sevoflurane
2%
VP of Sevoflurane
157
BGC of Sevoflurane
0.65
OGC of Sevoflurane
47
MOA of Sevoflurane
Unknown
MAC of Nitrous Oxide
104%
VP of Nitrous Oxide
38770mmHg
BGC of Nitrous Oxide
0.46
OGC of Nitrous Oxide
1.4
MOA of Nitrous Oxide
Unknown
MOA of Propofol
Gamma Aminobutyric acid agonist
PK of Propofol
First pass effect in Lungs
Hepatic Metabolism CYP450
(4-hydroxypropofol) active metabolite
not influenced by hepatic or renal dysfunction
highly protein bound in blood
pain on inject
decrease dose in eldery, increase dose in children
PD of Propofol
rapid and pleasant loss and return to consciousness
may induce myoclonus
neuroprotective
decrease in sympathetic tone and vasodilation
mild resp. depression common in induction doses
mild bronchodilation
Induction dose of Propofol
1.5-2.5MG/kg
TIVA dose of Propofol
100-300mcg/kg/min
MAC dose of Propofol
25-100mcg/kg/min
Vd for propofol
3.5-4.5 L/kg
Half-Life of Propofol
0.5-1.5 hour
Context sensitive half-time <40 mins
MOA of etomidate
Gamma-aminobutyric agonist
PK of Etomidate
large Vd
75% protein bound
metabolism by hydrolysis and plasma esterases
Etomidate inhibits
conversion of cholestrol to cortisol
11B-hydroxylase
causes adrenal cortical suppression
Etomidate is contraindicated in
patients with porphyrias
PD of Etomidate
rapid onset, return to consciousness 5-15 minutes
CBF and CMRO2 decreased
involuntary myoclonic movements >50% of patients
maintains hemodynamic stability
decrease in MV, but increase in RR
consider for cardiac compromised patients
increased risk for PONV
Induction dose of Etomidate
0.2-0.4 mg/kg
Vd of Etomidate
2.2-4.5L/kg
Half time of Etomidate
2-5 hour
MOA of Ketamine
N-methyl D-aspartate (NMDA) antagonist
PK of Ketamine
racemic mixture
not significantly protein bound
highly lipid soluble, rapid transfer of BBB
demethylation of CYP450
PD of Ketamine
produces dissociative anesthesia
has both amnestic and analgesic properties
increase CBF, CMRO2, and ICP (can be attenuated w/ benzo or opioid)
produces nystagmus, increase IOP
increases HR BP and SVR
Increased oral secretions
maintain spontaneous resp; slightly bronchodilator
risk for emergence delirium (attenuate with benzo)
indicated for trauma patients; possibly asthmatics
Induction Dose of ketamine
1-2.5mg/kg IV
4-8mg/kg IM
Multi-modal pain management of Ketamine
0.5-1mg/kg
Vd of Ketamine
2.5-3.5L/kg
Half-time of Ketamine
2-3 hours
5 Principle Pharmacologic effects of Benzodiazepines
anxiolysis anticonvulsant activity anterograde amnesia sedation/hypnosis skeletal muscle relaxation
Most common adverse effects of benzodiazepines
unexpected respiratory depression and oversedation
MOA of Midazolam
Gamma-Aminobutyric Acid (GABA) agonist
PK of Midazolam
water soluble with an imidazole ring (no discomfort on injection)
High lipid solubiltiy
highly pound to plasma proteins
metabolized by hydrolysis (1- hydroxymidazolam/4-hydroxymidazolam)
1-hydroxymidazolam half the activity
metabolism slowed by drugs that inhibit CYP450
PD of Midazolam
decreases CMRO2 and CBF
cerebral vasomotor responsiveness to CO2 is preserved
does not attenuate responses to intubation
Midazolam is synergisitc with
fentanyl
Midazolam at 0.2mg/kg produces
decrease in BP, increase in HR d/t changes in SVR
Midazolam should be avoided in patients with
acute porphyrias
Dosing of Midazolam
0.02-0.04mg/kg IV
0.4-0.8mg/kg oral
1-7mg/hr postoperative sedation
Vd of midazolam
1-1.7L/Kg
increased in elderly and obese
Half time of Midazolam
1.9 hours
2-4 Hours
MOA of diazepam
Gamma Aminobutyric Acid agonist
PK of Diazepam
insoluble in water and painful on injection
highly lipid solubility
crosses the placenta
extensively protein bound
metabolized by oxidation (desmethyl diazepam/oxazepam)
Exhibits a near-linear relationship between elimination half-life and patient age
Desmethyl Diazepam
may cause return of drowsiness at 6-8 hours and has a half life of 48-96 hours
PD of diazepam
produces minmial depressive effects on ventilation
minimal decrease in BP, CO, SVR
Diazepam has synergistic effects with
fentanyl that decreases BP and SVR
Diazepam should be avoided
in patients with acute porphyrias
Dosage of Diazepam for Seizures
0.1mg/kg IV effective in abolishing seizure activity
Vd of Diazepam
0.8-1.3 L/kg
Half time of Diazepam
20-50 hours
MOA of Lorazepam
Gamma-aminobutyrc acid agonist
PK of Lorazepam
most potent benzo, slowest onset of action
insoluble to water and pain on injection
conjugated with glucuronic acid in the liver (inactive metabolites)
less likely to be influenced by alteration in liver function
PD of Lorazepam
Duration of sedative effects last longer (6-10 hours)
delayed emergence and weaning of ventilator
Lorazepam should be avoided in patients with
porphyias
Dosage of Lorazepam
50mcg/kg
max: 4mg
Vd of Lorazepam
0.8-1.3L/kg
Half time of Lorazepam
10-16 hours
MOA of Flumazenil
Selective benzodiazepine antagonist (weak intrinsic agonist of GABA)
PD of Flumazenil
not recommended for patients being treated with anti-epileptic meds for seizure control
will not cause acute HTN, tachycardia or anxiety
will not alter MAC requirements
Dosing of Flumazenil
0.2mg IV followed by 0.1mg q1min
0.5-1mg completely abolish benzo effects
still unresponsive, have another problem
MOA Thiopental
GABA agonist
PK Thiopental
Rapid distribution
metabolized in liver by oxidation (pentobarbital active metabolite)
PD Thiopental
Decrease in CRMO2, CBF, ICP
reverse steel effect
decrease MAP and CO (decrease in venomotor tone and neg inotropic effects)
respiratory depression
Thiopental is contraindicated
intermittent porphyria
When is thiopental an medical emergency
inadvertent arterial administration
Induction dose of thiopental
2.5-5mg/kg
Vd of Thiopental
Large
Half life of Thiopental
relatively long (ten fold of propofol and prolonged in pregnacy d/t protein binding
Methohexital is used for
ECT
MOA of methohexital
GABA agonist
PK of Methohexital
rapid distribution
metabolized in liver by oxidation (pentobarbital active metabolite)
In Methohexital, what increases hypnotic potency but lowers seizure threshold and causes myoclonus
methyl on N
PD of methohexital
Decrease in CRMO2, CBF, ICP
reverse steel effect
decrease MAP and CO (decrease in venomotor tone and neg inotropic effects)
respiratory depression
INduction dose of methohexital
1-2 mg/kg
Vd of Methohexital
large
half life of methohexital
relatively long, (10 fold of propofol and prolonged in pregnancy due to protein binding)
Morphine MOA
opioid receptor agonist
PK of morphine
primary metabolism by conjugation and glucuronic acid
metabolite of morphine
morphine 6 glucronide
Morphine’s metabolite
longer DOA then morphine and higher analgesic potency 65x
Renal Function and Morphine
impaired renal function can result in accumulation and unexpected respiratory depression
PD of Morphine (CV)
bradycardia with sustained BP
orthostatic Hypotension
Morphine is synergistic with
benzos and N20
PD of Morphine (Resp)
dose dependent ventilation depression accompanied by compensation in tidal volume decrease responsiveness to CO2 decreased ciliary action increased airway resistance depression of medullary cough centers
PD of Morphine (CNS)
decreased CBF and ICP
miosis d/t edinger-westphal nucleus of oculomotor nerve
“When pain is relieved, sedation can occur”
PD of Morphine- General
muscle rigidity
spasms of biliary smooth muscle and sphincter of oddi
decreased gastric motility and constipation
increased N/V
urinary urgency
warmed flush skin and histamine release
Dosing of Morphine
2-4 mg
MOA Demerol (Meperidine)
Mu recpetor agonist
used for post-op shivering
PK of Demerol
1/10 as potent as morphine
metabolized by demethylization and hydrolysis (normeperidine)
decreased renal function can result in accumulation of metabolites
PD of Demerol
increase HR, mydriasis
delirium and seizures
Crosses the placenta
Demerol and patients taking MAOi
serotonin syndrome
Fentanyl MOA
opioid agonist
Dosing of Demerol
12.5 mg is for post-op shivering
PK of Fentanyl
rapid onset and highly lipid soluble
first pass uptake in lungs
metabolized by N-dealkylation and hydroxylation
Cirrhosis with Fentanyl
does not prolong elimination half-time
PD of Fentanyl
“secondary peaks” from pulmonary uptake
does not evoke histamine release
bradycardia is more prominent
increase ICP
Fentanyl is synergistic with
propofol and versed
Dosing of Fentanyl
1-3mcg/kg to blunt SNS to response and provide analgesia
Vd of fentanyl
large
>80% leaves the plasma in less than 5 mins
Fentanyl Context Sensitive 1/2 time
increases with infusion
>2hr
Sufentanil MOA
opioid agonist
PK of Sufentanil
5-10 more potent then fentanyl
extensive protein binding compared to fentanyl
significant first pass pulmonary uptake
Metabolized by N-deakylation and O-demethylation (desmethyl sufentanil)
clearance sensitive to hepatic flow and normal renal function important
PD of Sufentanil
decreased CMRO2
decreased HR and CO
may cause chest wall rigidity
Dosing of Sufentanil
0.1-0.4mcg/kg for analgesia (longer analgesia and respiratory depression than fentanyl)
Vd of Sufentanil
large
Context sensitive 1/2 time of Sufentanil
30 minutes
MOA Alfentanil
opioid agonist
PK of Alfentanil
less potent than fentanyl, shorter duration of action
metabolized by N-dealkylation
rapid onset
PD of Remifentanil
seizure like activity
decrease in BP and ventilation
no post-op pain coverage
Dosing of Reminfentanil
1-3 mcg/kg induction
0.1-0.3 mcg/kg/min infusion
Vd of Reminfentanil
small
Context sensitive 1/2 time of Reminfentanil
4 mins
PD of Alfentanil
acute dystonia; avoid with untreated Parkinson’s
Significant decrease in BP
Dosing of Alfentanil
15 mcg/kg
Vd of Alfentanil
small
Context sensitive 1/2 time fo Alfentanil
60 minutes
MOA of Remifentanil
selective Mu agonist
PK of Remifentanil
potency is the same as fentanyl
metabolized by non-specific plasma esterase
not affected by pseudocholinersterase deficiency
Remifentanil is synergistic with
propofol
1/2 Life of Fentanyl
2-4 hours
Life Life of Remifentanil
0.1-0.3 hours
1/2 Life of Sufentanil
2-5 hours
1/2 Life of Alfentanil
1 hour