General Anaesthetics Flashcards
agents that bring about reversible loss of all sensations and consciousness
general anesthetics.
list the 5 primary effects that characterizes the neurophysiological state produced by GA?
1- unconsciousness.
2- amnesia.
3- analgesia.
4- inhibition of autonomic reflexes.
5- skeletal muscle relaxant.
which type of anesthesia is generally used to minimize side effects?
balanced anesthesia.
list the types of drugs that are involved in balanced anesthesia?
inhaled anesthetics, intravenous anesthetics, sedative-hypnotics, opioids, neuromuscular blocking drugs.
the practice of clinical anesthesia requires integrating _________ and ____________ of each individual patient.
pharmacology of GA, and the pathophysiological state.
the choice of anesthetic agent depends on what?
1- status of organ systems.
2- concomitant use of drugs.
list the 3 classification of general anesthetics?
1- inhalational agents.
2- intravenous anesthetics.
3- dissociative anesthetics.
list the 2 types of inhalation agents?
1- gas.
2- liquids.
give an example of a gas inhalation agent?
nitrous oxide.
give examples of liquid inhalation agents?
1- halothane.
2- methoxyflurane.
3- desflurane.
4- isoflurane.
5- enflurane.
6- xenon.
list the 3 types of intravenous anesthetics?
1- barbiturates.
2- non-barbiturate.
3- benzodiazepines.
give examples of intravenous anesthetics barbiturates?
1- thiopentone.
2- methohexitone.
give examples of intravenous anesthetic non-barbiturates?
propofol.
give example of intravenous anesthetic benzodiazepines?
1- diazepam.
2- lorazepam.
3- midazolam.
give an example of dissociative anesthetics?
ketamine.
list the 4 states of general anesthesia?
1- pre-anaesthetic medication.
2- induction.
3- maintenance.
4- recovery.
general anesthesia is a reversible state of _______.
CNS depression.
give examples of pre anesthetic medication?
benzodiazepines.
give example of induction drugs?
thiopental, and propofol.
give an example of agents used in maintance?
inhaled or IV agents or both.
give an example of agents used in maintenance?
inhaled or IV agents or both.
the depth of anesthesia has four sequential stages, list them?
1- stage 1: analgesia.
2- stage 2: excitement.
3- stage 3: surgical anesthesia.
4- stage 4: medullary paralysis.
what happens in stage 1 (analgesia) of anesthesia?
loss of pain sensation.
what happens in stage 2 (excitement) of anesthesia?
- patient displays delirium.
- rise and irregularity in BP and respiration.
- rapid acting IV agents shorten this stage.
what happens in stage 3 (surgical anesthesia) of anesthesia?
- regular respiration and skeletal muscle relaxation with loss of spontaneous movement.
what happens in stage 4 (medullary paralysis) of anesthesia?
severe depression of respiratory and vasomotor centers occurs.
what stage of anesthesia is the ideal stage for surgery?
stage 3 (surgical anesthesia).
the minimum concentration of an inhalation agent required in the alveoli to produce unresponsiveness to the skin incision in 50% patients?
minimum alveolar concentration (MAC).
MAC is a measure of ______ of an agent?
potency.
greater is the MAC, _______ is the potency.
lesser
which drug has maximum MAC, thus least potency?
nitrous oxide.
which drug is the most potent, having the least MAC?
methoxyflurane.
Blood gas partition coefficient is determined by?
the solubility of an agent in blood
Blood gas partition coefficient determines what?
the speed of onset and recovery
Greater is the blood gas partition coefficient, _______ is the speed of onset
lesser
which drug is the fastest acting agent as it has minimum blood gas partition coefficient?
xenon.
which drug is the slowest acting agent (maximum blood gas partition coefficient)
Methoxyflurane
All inhalational agents result in what in the respiratory system?
respiratory depression
which inhalation agent causes respiratory depression?
Enflurane
Inhalation agents effects in the respiratory system: Blunt ventilatory response to?
hypercapnia and hypoxia
Blunt ventilatory response to hypercapnia and hypoxia is seen most with which inhalation agent?
halothane.
All inhalational agents cause what?
bronchodilation
All inhalational agents cause bronchodilation, seen the most with which drugs?
halothane in asthmatics
and with sevoflurane in non-asthmatics.
list the systemic effects of inhalation agents on the CVS?
1- Reduce cardiac output.
2- Reduce BP.
3- Baroreceptor reflexes are blunted.
which inhalation agents do NOT reduce cardiac output?
isoflurane and desflurane.
which inhalation agents show max decrease in BP?
Isoflurane.
which inhalation agent increases BP?
cyclopropane.
which inhalation agent is used for producing controlled hypotension?
isoflurane.
which inhalation agent is used for patients with shock?
cyclopropane.
which inhalation agent does NOT blunt baroreceptor reflexes?
isoflurane.
which inhalation agent is used in cardiac patients?
isoflurane.
which inhalation agents may result in hepatotoxicity?
halothane, chloroform, and methoxyflurane.
which drug can result in vasopressin resistant polyuric renal failure?
Methoxyflurane
which drug is added to decrease renal inflammability with methoxyflurane?
fluoride.
which drug can cause megaloblastic anemia?
nitrous oxide.
all inhalation drugs are good muscle relaxants except?
nitrous oxide.
max effect of muscle relaxation with which drug?
ether.
max analgesia is cause by which drug?
trilene.
ether is also a good _____ agent
analgesic.
which drug is also called laughing gas?
nitrous oxide.
nitrous oxide is a _____ analgesic agent but _____ anaesthetic.
good analgesic.
poor anaesthetic.
which drug has highest MAC?
nitrous oxide.
nitrous oxide is a _____ muscle relaxant.
poor.
nitrous oxide shows ________ induction and recovery of anesthesia
fast.
nitrous oxide is used in a concentration of ______% with ____% ____.
50-60% with 33% oxygen.
________ is a mixture of 50% N2O + 50% O2.
entonox.
what can occur when supply of N20 is stopped while recovery from anaesthesia?
Diffusion hypoxia
how can we prevent Diffusion hypoxia?
by 100% oxygen for a few minutes before stopping N20
which drug comes in a blue cylinder?
nitrous oxide.
which drug comes in amber colored bottles?
Halothane.
which drug contains thymol as preservative?
Halothane.
halothane is a _____ anaesthetic but very _____ analgesic agent
good anesthetic.
poor analgesic.
halothane relaxes which organ?
uterus.
halothane is used for what?
internal version and manual
removal of placenta
what is halothane contradicted in and why?
Contraindicated in labour: risk of postpartum hemorrhage (PPH)
halothane is agent of choice in what?
bronchial asthma.
why is halothane agent of choice in bronchial asthma?
has bronchodilator action.
halothane is agent of induction in which age group?
children.
list the properties of halothane?
- H- Hyperthermia (malignant hyperthermia)
- A- Arrhythmias (sensitizes the heart to adrenaline)
- L- Liver toxic
- O- Orthostatic hypotension
- T- Tocolytic
- H- Heart (inhibits heart > decreases cardiac output)
- A- Asthma (bronchodilator)
- N
- E- Non-Explosive
- C- Chills (post-anesthetic shivering)
- C- Catecholamines (sensitizes the heart to arrhythmogenic action)
- C- Children (safe in children)
isoflurane is _______ analgesic agent.
not a good.
cardiac output is maintained with which drug?
isoflurane.
which drug is the agent of choice for cardiac surgery?
isoflurane.
which drug produces the least increase in intracranial pressure?
isoflurane.
which drug is the agent of choice in neurosurgery?
isoflurane.
which drug produces max decrease in BP?
isoflurane.
which drug is the agent for producing controlled hypotension?
isoflurane.
which inhalation agent can be used in day care surgery?
isoflurane.
which drug is safe in pheochromocytoma?
isoflurane.
which drug is inflammable and explosive agent?
ether
which drug is the safest agent in unskilled hands?
ether
which drug is the agent of choice for induction in children?
sevoflurane.
which drug produces a nephrotoxic metabolite, Compound A: do not use in
closed circuit?
sevoflurane.
which drug is the most potent analgesic agent: used for analgesia in labour?
Trielene
which drug is the inhalational agent of choice in hemorrhagic shock (increases BP by increasing sympathetic tone)?
Cyclopropane
which drug is very close to an ‘ideal inhalational anaesthetic’?
xenon.
which drug Does not cause respiratory or cardiovascular depression?
xenon.
which drug is Not metabolised in the body?
xenon.
which drug is Stable in storage and has no interaction with anesthesia circuit or soda lime?
xenon.
which type of anesthetics are Used for rapid induction of anaesthesia?
Intravenous anesthetics
which type of anesthetics Provide sedation during Monitored Anaesthesia Care?
Intravenous anesthetics
which type of anesthetics are Used as sedative in ICU settings?
Intravenous anesthetics
which type of anesthetics Can also be used for maintenance of anaesthesia?
Intravenous anesthetics
which IV agent can be used for maintenance of anesthesia?
propofol
