NMBD Flashcards
Succinylcholine
Depolarizing Neuromuscular blocker
Partial Agonist
Uses;
-intubation
-tx laryngospasm
(in pedi mix 0.5mg/kg with 0.02mg/kg atropine)
MOA;
- binds to one or both of the alpha subunits of the nicotinic Ach receptors (mimics the action of acetylcholine)
- depolarizes the post junctional membrane causing brief period of excitation (fasciculation’s) followed by flaccid paralysis
- Paralysis occurs bc open cholinergic channels keep the cell membrane in a depolarized condition that effects the inactivation of VGNa channels so they can not support more AP
Dose; ED95; 0.3mg/kg Laryngospasm; 0.5mg/kg Intubation; 1mg/kg RSI; 1.5 mg/kg
Pharmacokinetics; intubation dose -onset; 30 - 90 seconds -E1/2t; 2 - 4 min -DOA; 8. - 15 min -Vd; 02L/kg -Pb; minimal
Metabolism; by pseudo-cholinesterase; not present at NMJ; termination of effect is by diffusion away
Side Effects;
- Cardiac dysrhythmias
- Hyperkalemia (increases K 0.5 -1 mEg/L)
- Masseter spasm
- Increased IOP
SE that can be Prevented with a defasiculation dose
- Increased ICP
- Increased IGP
- Myalgia (r/t fasciculation’s)
Contraindication;
- Hyperkalemia
- 3rd degree burn
- severe muscle trauma
- stroke
- neurological injury (quad/paraplegia)
- muscle wasting/ prolonged immobility
- extensive muscle denervation
- MH
- Duchenne MD
- Not to be used in kids under 8 yrs old unless emergency situation
Caution; Butyl-cholinesterase deficiency (dibucaine number, decreased number, less pseudocholinesterase, longer they will be intubated)
Rocuronium
non depolarizing neuromuscular blocking drug
amino steroid
Uses;
- improves intubating conditions
- provides immobility during surgery
- facilities mechanical ventilation
- higher dose used for RSI intubation
MOA:
-Directly prevents acetylcholine from binding to nicotinic receptors; inhibiting muscle cell depolarization
Dose; ED95; 0.3mg/kg intubation dose; 0.6mg/kg RSI dose; 1.2mg/kg de-fasiculating dose; 0.06- 0.1mg/kg
*effects reversed with anti-cholinesterase drug (neostigmine) or suggamadex Pharmacokinetics; -onset; 60 - 90 seconds -E1/2t; 1 - 2 hrs -DOA; 30 - 90 min -Vd; 0.25L/kg -Pb; 30 - 50%
metabolized by the liver
eliminated 30% unchanged in kidney and 50% in bile
Side Effects;
- increased/ decreased BP
- arrhythmia
- apnea
- bronchospasm
- mild vagolytic effect
Contraindications;
-conscious patient
Caution;
- in neurological disorder (MG, MS, GBS), burn pt, hemiplegia
- may be sensitive or resistant need to monitor twitches
- administration of ephedrine will decrease the onset time r/t increased CO
- administration of esmolol before Roc can increase onset time r/t decreased CO
Vecuronium
non-deploarizing neuromuscular blocking drug
amino steroid
Uses;
- improves tracheal intubation conditions
- facilitates mechanical ventilation
- provides immobility for surgery
MOA;
competitively binds to nicotinic Ach receptors and prevents acetylcholine from binding; blocking muscle cell depolarization
Dose;
ED95; 0.04mg/kg
intubation; 0.1mg/kg
Pharmacokinetics; intermediate acting -onset; 3 - 5 min -E1/2t; 65 - 75 min -DOA; 45 min -Vd; 0.2 - 0.4L/kg -Pb; 60 - 80%
metabolized by the liver in 3-OH metabolite
Excreted 20 - 30 % unchanged by kidneys and 25 - 50% in the bile
Side Effects;
- sever bronchospasm
- cardiac arrest (SA node exit block)
Contraindication;
- conscious patient
- hypersensitivity to vec, pancuronium, Roc and Mivacurium
Caution;
DOA prolonged with hypothermia, renal/ liver disease, elderly and obesity
Ver comes in powder Forman must be dissolved in sterile water before use
Pancuronium
synthetic steroidal non-depolarizing neuromuscular blocking drug
Uses;
- improves tracheal intubating conditions
- provides immobility for surgery
- facilitates ventilation
MOA;
-competitively binds to nicotinic acetylcholine receptors at the NMJ and blocks acetylcholine from binding; prevents eating muscle cell depolarization
Dose
ED95; 0.07mg/kg
intubating; 0.08 – 0.1mg/kg
Pharmacokinetics; long acting -onset; 3 - 5min -E1/2t;? -DOA; 85 min (CB) drug card 130 – 220min -Vd; 0.25 - 3 L/kg -Pb; minimal
metabolized by the liver in 3-OH
eliminated 80% unchanged by the kidneys
Side Effects;
- bronchospasm
- tachyarrhythmia
- vagolytic
- SNS stimulation (indirect release of NE); increase HR and BP
- excessive salivation
Contraindications;
-hypersensitivity
caution;
- impaired renal and liver dysfunction
- underlying CV disease
*store in the fridge
Mivacurium
Benzylisoquinolinium
short acting
non depolarizing neuromuscular blocking drug
Uses;
- improves intubating conditions
- provides immobility for surgery
- facilitates ventilation
MOA:
-competitively binds to nicotinic Ach receptors and prevents Ach from binding; preventing cell muscle depolarization causing paralysis
Dose;
ED95; 0.067mg/kg
intubating; 0.15 - 0.25mg/kg
Pharmacokinetics ; short acting -onset; 2 - 3 min -DOA; 16 min -Vd; 0.2L/kg
- metabolized by pseudocholinesterase
- eliminated <5% unchanged in urine
Side Effects; -histamine release -hypotension -tachycardia -bronchospasm Dose of <0.15mg/kg little to no CV effects
Contraindicated;
- Asthma
- Butyl-cholinesterase deficiency (lower dibucaine number, prolonged DOA)
Atracurium
Benzylisoquinolinium
Intermediate acting
non depolarizing neuromuscular blocking drugs
Uses;
- improves intubating condition
- provides immobility for surgery
- facilities ventilation
MOA;
competitively binds to nicotinic Ach receptors and prevents Ach from binding; blocks muscle cell depolarization; causing paralysis
Dose;
ED95; 0.21 mg/kg
Intubation; 0.5 mg/kg
Pharmacokinetics; -onset; 1 - 3 min -DOA; 20 - 50 min -Vd; 0.15 L/kg Pb; 82%
metabolized by Hoffman Elimination (pH and temp dependent) and ESTER hydrolysis
Laudanosine tertiary amine (by product of Hoffman elimination) crosses BBB causes CNS stimulations
Laudanosine is metabolized by liver (70%) excreted in urine (30%)
Side Effects;
- histamine release
- tachycardia
- hypotension
- bronchospasm
- skin flushing
Contraindication;
- Asthmatics
- Seizure disorder
Caution;
-renal and liver dysfunction (accumulation of laudansosine)
Cisatracuirum
Benzylisoquinolinium
non depolarizing neuromuscular blocking drug
more potent than atracurium (less laudansosine production)
Uses;
- improves intubating conditions
- provides immobility for surgery
- facilities ventilation
MOA;
competitively bind to Ach receptors at the NMJ; blocks Ach from binding, prevents muscle cell depolarization causing paralysis
Dose;
ED95; 0.05mg/kg
intubating; 0.1 - 0.2 mg/kg
Pharmacokinetics;
- onset; 3 - 5 min
- DOA; 60 - 90 min
- Vd; 0.12 - 0.2L/kg
-metabolized by Hoffman Elimination (pH and temp dependent) produces byproduct
Laudanisone (tertiary amine; crosses the BBB and causes CNS stimulation)
-Elimination 20% by liver and kidney
Side Effects;
-no real side effects noted
Contraindications;
- anaphylaxis
- onset prolonged in elderly
