Useful for Pharmacy students

1. Definition:-
 These are agents that reversible loss of
consciousness and sensation. so as to enable
surgical operations to be carried out.
Chloroform was introduced by james simpson
in over the decades.
Halothane was introduced in to anaesthetic
practice by Johnson in 1956
General anaesthetics
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3. classification
1.Inhalational anaesthetics:-
gases volatile liquids
nitrous oxide halothane
enflurane
Isoflurane
desflurane
sevoflurane
ether
methoxy flurane
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4. 2.Intravenous anaesthetics (non-volatile
anaesthetics):-
a. Faster acting drugs:-
1.Barbiturates:-Thiopentone sodium, metho
hexitone sodium
2.Non-barbiturates:- Propofol, etomidate
b. Slower acting drugs:-
 Benzodiazepines ----diazepam,lorazepam,
midazolam
 Dissociative anaesthesia---ketamine
 Opioid analgesics----- fentanyl
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5. MOA of GA
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6. NITROUS OXIDE
• Rapid induction and recovery
• Good analgesic
• Low potency
• Risk of bone marrow depression with prolonged
administration
HALOTHANE
• Widely used agent
• More potent
• Non explosive ,non irritant
• Hangover due to high lipid solubility
• Repeated use damages liver
• Drug of choice in children
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7.  ENFlURANE
• Fast induction and recovery
• Like halothane it also decrease HR,CO, BP.
• It induces seizures
• Has greater respiratory depressant action
ISOFLURANE- structurally similar to enflurane
DESFLURANE – structurally similar to Isoflurane & has
anesthetic actions similar to halothane
INTRAVENOUS ANESTHETICS
 THIOPENTONE
Ultra short acting barbiturates
Produces anesthesia with in 15 to 20 seconds
Weak muscle relaxant and analgesic activity
Cough and hiccup may occur during induction
It will depress respiratory system
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8. Ketamine
• It is used for short procedures like
bronchoscopy
• Blood pleasure & heart rate are increased
• Does not affect on respiration
• Muscle relaxation is poor
• Malignant hyperthermia
• Nausea and vomiting
• Aspiration pneumonia
• Respiratory depression
• Fall in blood pressure
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10. Drug interactions:-
Anesthetics will reduce the blood pressure if
we give it along with anti hypertensive's
Neuroleptics, Opioids, will potentiate the
action of anesthetics
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