Oral: NMB Flashcards
Class: SUCCINYLCHOLINE
Depolarizing NMB
MOA: SUCCINYLCHOLINE
Mimics ACh at the NMJ, opening channels and depolarizing post junctional membrane and prohibiting effect of ACh. (causes excitation & fasciculations followed by flaccid paralysis–> inhibits muscle contraction and channels stay OPEN)
Pharmacokinetics: SUCCINYLCHOLINE
NOT highly PB Onset = 30-60sec DOA = < 15min Metabolism= Rapidly hydrolyzed by PChE Elimination = renal E1/2t = 4min
SE: SUCCINYLCHOLINE
- MH + masseter spasm
- hyperK
- rhabdo, myoglobinuria
- inc ICP, IOP
- HISTAMINE
- dec HR BP
CI: SUCCINYLCHOLINE
- MH hx
- renal pt w/ inc K (must be less than 5.5)
- peds – unless emergency
- asthma/COPD d/t histamine
- musc weakness pts – DMD, paralysis
Dose: SUCCINYLCHOLINE
I: 1 mg/kg
RSI: 1.5 mg/kg
Laryngo: 10-20 mg
Continuous infusion: 2.5 mg/min (0.5 to 10 mg/min). Dilute to 1-2 mg/ml
Class: DANTROLENE
Direct, centrally acting muscle relaxant – used to treat MH
MOA: DANTROLENE
dec muscle tone + metabolism by restoring the balance btw the release and uptake of Ca+
- prevents the ongoing release of Ca+ from the sarcoplasmic reticulum = dec muscle contraction
- blocks external entry of Ca+ into the sarcoplasm
- hypothesized to inhibit Ca+ conductance through the Ryanodine channels
(Does NOT potentiate effects of NDMR and does NOT interfere w/ reversal of muscle relaxants )
PK: DANTROLENE
Onset < 5min DOA = 3hr 5-hydroxydantrolene, 30 – 50% potency Hepatic metabolism Hepatic and renal elimination E1/2t = 10-15hrs
SE: DANTROLENE
- skeletal musc. weakness – may need to stay intubated
- inc HR, labile BP
- hepatitis if used > 60 days
- phlebitis
- seizures
CI: DANTROLENE
Duchenne’s muscular dystrophy + pre-existing muscular dz pts
CCBs = life threatening hyperK and myocardial dep.
Dose: DANTROLENE
Bolus: 2.5 mg/kg – followed by:
Maintenance: 2 mg/kg IV q5min for a total of 10 mg/kg
Then 70mg IV q6hrs for 72 hrs
can switch to PO dantrolene for a few days after MH is resolved
Class: ATRACURIUM, CISATRACURIUM, MIVACURIUM, d-TUBOCURARINE
Nondepolarizing NMB
benzylisoquinolone
MOA: All NDNMB
competitive antagonist
acts on pre/post syn cholinergic receptors and produces NMB by blocking passage of ions through nAChR
PK: ATRACURIUM
80% PB Water sol. Onset = 1-3min DOA = 30min Active met = Laudanosine (accumulates w/ RF – can cause seizures) Met = 2/3 ester hydrolysis, 1/3 hoffman elim – temp/pH dep. Elim = renal E1/2t = 30min
SE: ATRACURIUM
- HISTAMINE
- dec BP inc HR
- flushing
- prolonged action w/ IA, abx, AEDs
CI: ATRACURIUM
- caution w/ metabolize w/ RF/LF
- asthma/COPD
- hypersensitivity
Dose: ATRACURIUM
0.5 mg/kg
Redose: 0.1 mg/kg 15-45 min later
PK: CISATRACURIUM
Water sol Onset = 2-3min DOA = 30min Active met = Laudanosine – 1/5 of atrac Met = 80% hoffman elim – temp/pH dep. Elim = renal + feces E1/2t = 30min
Good for RF
NO histamine!
SE: CISATRACURIUM
- MINIMAL se!!
- prolonged action w/ abx, LA, Li
- seizures w/ RF (d/t laudan)
CI: CISATRACURIUM
- hypersensitivity
2. musc weakness
Dose: CISATRACURIUM
0.2 mg/kg
Redose: 0.02 mg/kg 40-60 min later
PK: MIVACURIUM
Onset = 1-2min DOA = 20min Met = Rapidly hydrolyzed by PChE Elim = renal E1/2t = 55min
Good for RF
Good for peds – faster onset + recovery
Can reverse w/ edrophonium
SE: MIVACURIUM
- HISTAMINE
- inc HR dec BP
- bronchospasm
CI: MIVACURIUM
- prolonged w/ atypical PChE activity
- asthma/COPD
- hypersensitivity
Dose: MIVACURIUM
Intubation: 0.2-0.25 mg/kg
Class: ROCURONIUM, VECURONIUM, PANCURONIUM
Nondepolarizing NMB
Steroidal
PK: ROCURONIUM
Onset = 1-2min DOA = 30min Met = Hepatic Elim = Renal - 30% excreted unchanged 50% biliary excretion E1/2t = 1-2hr
NO histamine
SE: ROCURONIUM
- cardiac stable!!
- dec doa w/ IA, LA
- bronchospasm
- salivation
- inc doa w/ RF/LF
CI: ROCURONIUM
- hypersensitivity
2. MG
Dose: ROCURONIUM
I: 0.6 mg/kg
RSI: 1.2 mg/kg
PK: VECURONIUM
70% PB Onset = 2-3min DOA = 30min Active met = 3-desacetyl vec – 50% as potent Met = Hepatic Elim = Renal - 30% excreted unchanged 50% biliary excretion E1/2t = 70min
NO histamine
SE: VECURONIUM
- bronchospasm
- NO CV effects!
- inc doa w/ IA + abx
- inc doa w/ RF/LF
CI: VECURONIUM
- hypersensitivity
Dose: VECURONIUM
0.1 mg/kg and then 10% dose for redosing (for all?)
PK: PANCURONIUM
Small PB Onset = 2-3min DOA = 60-90min Active met = 3-desacetyl panc – 50% as potent – accumulates in renal, biliary + liver dz, elderly + obese Met = 20% Hepatic Elim = Renal - 80% excreted unchanged 50% biliary excretion - dec dose 50% in LF E1/2t = 2hr
NO histamine
Inhibits PCHE activity
SE: PANCURONIUM
- inc HR, BP, CO – hit them w/ a pan!
- bronchospasm
- ins doa w/ IA, abx, AEDs
- musc weakness
CI: PANCURONIUM
- CAD, HF, HD
- renal dysfx
- hypersensitivity
- pheochromocytopma
Dose: PANCURONIUM
0.1 mg/kg and then 10% dose for redosing (for all?)
