gas notes 2 Flashcards
Can Suxamethonium be reversed?
No, Suxamethonium cannot be reversed
It is short-acting, which is why reversal is not necessary.
What agents are used to reverse non-depolarising muscle relaxants?
A combination of anticholinesterase and anti-muscarinic agents
This combination helps restore muscle function after the use of non-depolarising muscle relaxants.
How do non-depolarising muscle relaxants work?
They out-compete acetylcholine (ACh) for binding sites on post-synaptic ACh receptors
This mechanism prevents muscle contraction.
What enzyme breaks down acetylcholine in the synaptic cleft?
Acetylcholinesterase (AChE)
AChE is essential for terminating the action of ACh.
What happens when acetylcholinesterase is inhibited?
Less ACh is broken down, allowing more ACh to compete with muscle relaxants
This leads to the restoration of muscle function.
Fill in the blank: Non-depolarising muscle relaxants can be reversed using a combination of _______ and anti-muscarinic agents.
anticholinesterase
True or False: Suxamethonium is a long-acting muscle relaxant.
False
Suxamethonium is short-acting.
What is the result of increased ACh in the synaptic cleft?
Muscle function returns
More ACh allows for competition with muscle relaxants at the receptors.
What effect do cholinesterase inhibitors have on ACh in the parasympathetic nervous system?
They cause ACh to accumulate.
What are the significant cardiovascular effects of ACh accumulation due to cholinesterase inhibitors?
Bradycardia and hypotension.
How can the unwanted effects of cholinesterase inhibitors be counteracted?
By co-administering an anti-muscarinic agent.
Name two examples of anti-muscarinic agents used to counteract cholinesterase inhibitors.
- Atropine
- Glycopyrolate
What is sugammadex?
A tubular molecule that traps rocuronium and vecuronium in its core, preventing their action on post-synaptic ACh receptors.
Sugammadex is used to reverse neuromuscular blockade caused by these agents.
What does sugammadex trap?
Rocuronium and vecuronium.
These are neuromuscular blocking agents used in anesthesia.
How does sugammadex prevent the action of rocuronium and vecuronium?
By trapping them in its core.
This trapping mechanism stops these drugs from binding to ACh receptors.
When should sugammadex be used?
For urgent reversal of profoundly paralysed patients.
Its high cost limits its use to critical situations.
True or False: Sugammadex is inexpensive and can be used routinely.
False.
Sugammadex is very expensive.
What are the risks associated with extubation?
Laryngospasm, aspiration, apnoea
Extubation can lead to sudden airway emergencies.
What is the ideal patient condition for extubation? List at least three aspects.
- Adequately fasted
- Haemodynamically stable
- Easy to re-intubate
- Adequately oxygenated
- No longer paralysed
- Breathing spontaneously
- Awake enough to obey commands
These conditions help minimize the risks during extubation.
True or False: It is acceptable to extubate a patient who is still paralysed.
False
Patients should not be paralysed at the time of extubation.
What should you do if the patient tries to pull the tube out themselves?
Help them
Assisting the patient is crucial to avoid airway complications.
What is the first step to take when preparing for extubation?
Pre-oxygenate
This ensures that the patient has adequate oxygen levels before the tube is removed.
Fill in the blank: After pre-oxygenating, insert a _______.
bite block
A bite block helps prevent damage to the airway during extubation.
What should be done to the airway before extubation?
Suction the airway with your Yankauer sucker
This helps clear secretions that could obstruct breathing.
