Cholinergic Drug Lec. 3 Flashcards
(19 cards)
What is drug act NONDEPOLARIZING NM blockers;
Tubocurarine
What is drug act DEPOLARIZING NM blockers
Succinylcholine
What is drug act NONDEPOLARIZING NM blockers with Short –acting
Mivacurium 20 min,gallamine
What is drug act NONDEPOLARIZING NM blockers Intermediate-acting
Atracurium, Cisatracurium , Rocuronium and vencuronium
30 min
What is drug act NONDEPOLARIZING NM blockers; Long-acting:
Pancuronium 40 min
Who we can stoped the effect of NONDEPOLARIZING NM blockers
Their action can be overcome by increasing conc. of acetylcholine in the synaptic gap(by ihibition of acetyle choline estrase enzyme)
• e.g.: Neostigmine ,physostigmine edrophonium
What the drug is administered before neostigmine, to prevent the parasympathetic effects of acetylcholine by blocking muscarinic receptors
Atropine
What are drugs from Non-depolarizing Agents (Competitive Blockers) that metabolised in liver and we cannot give it in patient with liver problem
vecuronium, rocuronium)
What are drugs from Non-depolarizing Agents (Competitive Blockers) that cannot give it in patient with renal problem?
(tubocurarine, mivacurium, metocurine)
What is drug is degraded spontaneously in plasma by ester hydrolysis (Hofmann elimination),it releases histamine and can produce a fall in blood pressure ,flushing and bronchoconstriction. is metabolized to laudanosine ( which can provoke seizures?
Atracurium
What is drug degraded spontaneously in plasma and by ester hydrolysis and does not accumulate and hence it is used in patients with hepatic
and renal failure
Cisatracurium
What is
Unwanted effects of NONDEPOLARIZING NM blockers;
Fall in arterial pressure chiefly a result to ganglion block , may also be due to histamine release this may give rise to bronchospasm (especially with tubocurarine ,mivacurium ,and atracurium)
• Gallamine and pancuronium block, muscarinic receptors also, particularly in heart which may results in to tachycardia.
What are ACTIONS of NONDEPOLARIZING NM blockers
• All the muscles are not equally sensitive to blockade.
• Small and rapidly contracting muscles are paralyzed first.
• Respiratory muscles are last to be affected and first to recover.
What is drug with in DEPOLARIZING AGENTS
Suxamethonium ( succinylecholine)
(scoline)
Whate the phases of DEPOLARIZING AGENTS drugs
- Phase I block (= depolarizing)
- Phase II block (Desensitizing)
What are Pharmacokinetics of DEPOLARIZING AGENTS
• When rapid endotracheal intubations is required.
• Electroconvulsive shock therapy.
Unwanted effects of DEPOLARIZING AGENTS
Bradycardia preventable by atropine.
• Hyperkalemia in patients with trauma , burns, R-F
• this may cause dysrhythmia or even cardiac arrest.
• Increase intraocular pressure due to contracture of extra ocular muscles .
• increase intragastric pressure which may lead to emesis and aspiration of gastric content.
• Increase intracranial pressure
• Malignant hyperthermia: rare inherited condition probably caused by a mutation of Ca++ release channel of sarcoplasmic reticulum, which results muscle spasm and dramatic rise in body temperature. (This is treated by cooling the body and administration of Dantrolene)
• Prolonged paralysis: due to factors which reduce the activity of plasma cholinesterase
• genetic variants as abnormal cholinesterase, its severe deficiency.
• anti -cholinesterase drugs
• neonates, old age
• liver disease
What are Contraindications of succinylcholine
History of malignant hyperthermia
• Acute narrow angle glaucoma
• Penetrating eye injury
• Allergy to succinylcholine
• Extensive muscle trauma & burn
• Cerebrovascular accident
• Peptic ulcer
• C/I in case of head injury
What are drugs act muscarinic receptors also, particularly in heart which may results in to tachycardia?
Gallamine and pancuronium
