A-4. Inhalation anaesthetics Flashcards
inhalation anesthetics drugs
inorganic: N2O
organic: halothane, Isoflurane & Sevofluran
stages for GA
- premed
- induction
- maintenance
- awakening
requirements for maintenance
total unconsciousness
muscle relaxation
analgeasia
mécanisme of action of inhalation anesthetics
activation of Cl- channels
inhibits NA+ channels
potency of inhalation anesthetics
MAC (minimum alveolar concentration)
concentration at which 50% of patients are immobile
what does solubility for inhalation anesthetics mean?
rate at which partial pressure of an inhalation anesthetics reaches equilibrium btwn various tissues
(defined by blood gas coefficient)
inhalation anesthetics with low solubility are eliminated…
faster => shorter recovery time
Isoflurane
rapid induction & recovery
effects: analgesia, muscle relaxation & hypnosis
careful for breath holding & renal patients
Sevoflurane
Rapid induction & recovery
bronchodilation
less irritation, less potent (less side effects)
inhalation anesthetics indication
GA induction & maintenance
inhalation anesthetics contraindications
younger, pregnant & lactating
inhalation anesthetics side effects
cardiovascular & Resp dep
malignant hyperthermia
arrhythmia
(rare: hepato-nephrotoxic)
desflurane
low potency
not suitable for maintenance as it is irritates respiratory tract (laryngospasm)
& increase of CSf pressure
methoxyflurane
lowest potency
slow response, excitation used for maintenance
high risk in reptiles
N2O
not suitable for induction of maintenance alone, needs to be combined with other anesthetics
analgesic effects at high inhaled concentration
