Neuromuscular Blockers Flashcards
✓ Treat spasticity and muscle spasms
✓ Not recommended as a first line
Diazepam ( Valium)
Adverse effects of diazepam are
✓ Sedation
✓ Dependence
✓ Abuse
Is an analogue of GABA that bind into GABA b presynaptic and postsynaptic.
Baclofen
Has an analgesic effect by inhibition releasing of substance P .
Baclofen
Adverse effect of baclofen are
Sedation
Drowsiness
Confusion
Depression
Gastrointestinal disturbances
Hyperactivity and seizures
Is an alpha 2-adrenoreceptor agonist
Tizanidine
Inhibit presynaptic release of excitatory neurotransmitter leading to reduce the excitability of postsynaptic alpha - motor neurons
Tizanidine
Adverse effects of Tizanidine
Dry mouth
Hypotension
Drowsiness
Fatigue
Dizziness
Has only 10% of the antihypertensive activity of the alpha 2 adrenoceptor agonist clonidine
Tizanidine
Uses of centrally acting skeletal muscle relaxant
Spasticity
Hemiplegia
Amyotrophic lateral sclerosis and MS
Metabolized by plasma hydrolysis by nonspecific esterase’s
Atracurium and cisatracurium
Metabolized in liver
Vecuronium
Like suxamethonium is metabolized by Cholinesterase
Mivacurium
Prolong action of ACh and rapidly reverse competitive neuromuscular junction blockade
Neostigmine
Specific antagonist for the rocuronium and vecuronium by chelating them in the core and reducing their plasma concentration. The complex is then eliminated by the kidneys
Sugammadex
Adverse effects of non depolarizing NMBs
✓ Histamine release leading to hypotension and bronchospasm
✓ Respiratory paralysis in high doses
Contraindications of non depolarizing NMBs
✓ Bronchial asthma
✓ Myasthenia gravis
✓ With Amino glycosides or quinidine ( they can aggravate Ms paralysis.
It is ester of ACh
Suxamethonium (succinylcholine)
Metabolized by plasma pseudo ChE enzyme
Succinylcholine
Reversal block of succinylcholine by
Neostigmine block in phase 2
Fresh blood transfusion
Adverse effects of succinylcholine are
Bradycardia
Acute hyperkalemia
Sudden arise of IOP
Postoperative muscle pain
Prolonged respiratory paralysis
Malignant hyperthermia
Contraindications f using succinylcholine
Glaucoma or recent eye surgery
Congenital deficiency of PsChE enzyme
Therapeutic uses of neuromuscular blockers
Endotracheal intubation
To induce skeletal muscle relaxation
To control convulsions during ECT
Inhibitors of acetylcholine release
Botulinum toxin
Therapeutic uses of botulinum toxin
✓Injected locally
✓Treat involuntary movements such as blepharospasm
✓To relieve focal spasticity
✓To temporarily remove wrinkles
✓ Facial muscles for the prophylaxis of migraine
✓ Intravesical injection to treat overactive bladder syndrome
It is an antagonist at the ryanodine receptor that inhibits the release of Ca from the sarcoplasmic reticulum of the skeletal muscle.
Dantrolene
Therapeutic uses of dentrolene
✓ Treatment of malignant hyperthermia and neuroleptic malignant syndrome
✓Management of spasticity from disorders
Adverse effects of dentrolene
✓ Sk Ms weakness, dyspnea, dysphasia, somnolence
✓ dose dependent diarrhea, abdominal pain
✓ dose related risk of hepatitis
