NMB Dosages Flashcards
Sux
Depolarizing: Non Competitive
ED95: 0.3-0.63 mg/kg
Typical dose: 0.3-1.0 mg/kg
Onset: 45-60 seconds at 1.0mg/kg
Duration: 8-15 minutes for 90% recovery
Low dose: both negative inotropic and chronotropic occur
High dose: tachycardia may occur
dTc
BZQ: Non Depolarizing: Competitive
ED95: 0.5 mg/kg
Duration: 75-85 (Long Acting)
*increased duration in liver/renal failure up to 100 min
What can decrease BCE activity and affect SUX?
- liver disease
- advanced age
- malnutrition
- pregnancy
- burns
- oral contraceptives
- MAOIs
- echothiophate
- cytoxic drugs
- neoplasams
- anticholinesterases
- **less BCE activity, less SUX metabolism= prolonged duration of action
Contraindications of SUX
-eye injuries with open anterior chamber
can increase ICP?
-increase intra-gastric pressure: gastroesophageal issues (pregnancy, ascities, bowel obstruction, hiatial hernia)
NMDRs are ___________
- quartnary ammonium chemical compounds that have at least 1 positively charged nitrogen atom that binds to the alpha subunit of the post junctional cholingeric receptor
- allows them to bind to the nicotinic receptor
Benzylisoquinoliniums (BZQs)
- nitrogen atoms are incorporated into isoquionline ring systems resulting in bulky molecule
- ganglion-blocking and histmaine releasing properties of dTc are probably due to the tertiary amine function
- methylation of dTC at the tertiary amine and at the hydroxyl groups= metocurine which is 2X potent as dtc but has much lower histamine and ganglionic blocking properties
- bisquarternary are more potent than mono quart
- substituting methyl groups on quaternary nitrogen with a bulkier group reduces potency and duration of action
BZQs are very______________
-potent NDMR
-as potency increases, the speed of the onset of action (muscle relaxation) decreases
less potent= fast onset, more potent slow onset
-as potency increase, SE decrease (more potent= less total molecules of drug given to achieve desired effect=less side effects)
-lack vagolytic properties. No increase HR with standard doses
-increased histamine release compared to other NDMRs
-excreted by the kidneys
-atracurium- Hofman elimination
Doxacurium
BZQ: NDMR: Competitive
ED95: 0.025-0.030 mg/kg
Slow onset: 5-10 minutes
Double dose= 90 minute duration though*
NO CARDIAC EFFECTS
Atracurium
BZQ: NDMR: Competitive
ED95: 0.25 mg/kg
Onset: 3-5 minutes
Duration: 30-45 minutes
*constantly metabolized, no buildup of drug
If given rapidly or in high doses= hypotension and tachycardia, likely d/t histamine
-Can give h1/h2 blocker before
Cis-Atracurium
BZQ: NDMR: Competitive
ED95: 0.05 mg/kg
Onset: 3-5 minutes
Duration: 20-35 minutes
Typical intubating dose: 0.1-0.2 mg/kg (duration 60-70 minutes)
- NO CV EFFECTS
- great for patients w/ renal or liver failure
Steroidal NMB
-1 of 2 nitrogen atoms is quarternized
Pancuronium
Bisquarternary aminosteriod NDMR: competitive
*high potent, no hypotension, TACHYCARDIA- vagolysis
ED95: 0.07 mg/kg
Onset: 3-5 minutes
Duration: 60-90 minutes
Intubating dose: 0.08- .1 mg/kg (faster onset but would have almost 3 hours of relaxation–be careful)
- great for long anesthetics
- good when slight tachy is OK
Pipecuronium
Bisquart Aminosteriod NDMR: competitive
- Good drug for very long cases where extubation is not likely
- concerns about residual blockade and respiratory depression, pneumonia*
- stable from CV standpoint
Vecuronium
-SHORTAGE: only pediatric ICU infusion
Bisquart Aminosteroid NDMR: competitive
POWDER
ED95: 0.03-0.05 mg/kg
Intubating dose: 0.10-0.20 ( can go as high as 4X ED95= no cv effects)
-Duration: 25-40 minutes
-Infusion: 2-8 mcg/kg/min
Rocuronium
Bisquart Aminosteroid NDMR: competitive
ED95: 0.3 mg/kg
Onset: 3-5 minutes
Duration: 18-30 minutes
Typical intubating dose: 0.4-0.6 mg/kg
Duration: 25-45 minutes
Mild increase in HR
NO ganglionic block or histamine
