Drugs: doses, MOA, etc Flashcards
fentanyl dosing
1-2mcg/kg low dose; awake patients
2-20mcg/kg
fentanyl MOA
binds to opioid receptors of the presynaptic and postsynaptic sites in the CNS and peripherally
major advantages of fentanyl
- no direct myocardial depression
- no histamine release
- suppresses stress response to surgery
fentanyl side effects
- respiratory depression
- increased ICP
- reflex coughing
- decreases HR
Propofol dosing
2-2.5mg/kg
propofol MOA
GABA receptor agonist (enhances inhibition), hyperpolarizes cell membranes
propofol common side effects
- decreases HR, BP, RR, CMRO2, CBF, and ICP
- injection site pain
- inhibits platelet aggregation
advantages of propofol
- fast on/off with minimal residual effects
- antiemetic
- antipruritic
- anticonvulsant
Ketamine dosing
1-2mg/kg
ketamine MOA
NMDA receptor antagonist; inhibits glutamate; inhibits catecholamine uptake in postganglionic nerves
ketamine side effects
“increases everything”: ICP, BP, HR, O2 demands
-emergence delirium
advantages of using ketamine
- bronchodilating properties
- maintains spontaneous ventilation
what 2 drugs are often administered with ketamine
glycopyrrolate and benzo for secretions and emergence delirium
Etomidate dose
0.3mg/kg
Etomidate MOA
mimics inhibitory effects of GABA by increasing the receptors affinity to GABA; depresses the reticular activating system; opens Cl channels
avoid etomidate with what patients
seizure
major disadvantages of etomidate
- emetic
- adrenocortical suppression
advantage of etomidate
good hemodynamic profile
Dexmedetomidine dosing
loading dose: 0.5-1mcg/kg over 10min
infusion: 0.2-1.4mcg/kg/hr
Dexmedetomidine MOA
alpha 2 agonist: hyperpolarizes cell w/ efflux of K, reduced NE release, decreased cAMP by inhibiting adenylyl cyclase
Side effects of precedex bolus
bradycardia and HTN
Midazolam dosing
1-2mg IV
0.3-0.5mg/kg PO
midazolam MOA
causes increased binding of GABA to its receptor-> opening of Cl channel-> hyperpolarization
cardioprotectant feature of versed
prolongs adenosine
unique feature of versed
imidazole ring makes its lipid-soluble at pH >4
Lidocaine dosing
1-1.5mg/kg
max w/o epi: 4.5mg/kg
max w/ epi: 7mg/kg
rocuronium dosing
ED95: 0.3mg/kg
Intubating dose: 0.6mg/kg
non-depolarizing MOA
competes with Ach at nicotinic receptor alpha subunits, prevents the opening of Na ion channel, which prevents depolarization
depolarizing MOA
binds to alpha subunits on nicotinic receptor causing depolarization
roc metabolism
hepatic > renal
succinylcholine dosing
1-1.5mg/kg
succinylcholine metabolism
plasma cholinesterases
Cisatracurium dosing
ED95: 0.05mg/kg
Intubating dose: 0.2mg/kg
cisatracurium metabolism
Hoffman elimination
cisatracurium benefits over atracurium
less histamine release and less laudanosine formation
vec dosing
ED95: 0.05mg/kg
intubating dose: 0.1mg/kg
Neostigmine MOA
acetylcholinesterase inhibitor
Neostigmine dose
0.04-0.07mg/kg