Conduct of Anaesthesia Flashcards
When is IV induction of anaesthesia avoided?
In the severely ill
In pregnancy
What agents are used for IV induction of anaesthesia
Thiopentone
Propofol
Other agents
What are the characteristics of IV anaesthesia?
- Rapid
- One “arm-brain” circulation ~ 20s
- No obvious planes
- Easy to overdose
- Generally rapid loss of airway reflexes
- Apnoea is very common
When is gas induction of anaesthesia used?
In children
In adults with learning difficulties
What is the usual agent for gas induction of anaesthesia and what are it’s characteristics?
Sevoflurane
Acts slow
Displays planes of anaesthesia
What are the planes of anaesthesia?
- Analgesia/sedation
- Excitation
- Anaesthesia (light to deep)
- Overdose
How is loss of consciousness following induction of general anaesthetic monitored?
- Loss of Verbal Contact
- Movement
- Respiratory Pattern
- Processed EEG
- “Stages” or “planes” of anaesthesia
When and how is airway maintenance given to a patient under general anaesthetic?
Airway maintenance always needed under general anaesthetic
Can be done with:
-Simple maneuvers- head tilt/chin lift/jaw thrust
-Equipment- face mask/oropharyngeal airway/nasopharyngeal airway
What happens when an oropharyngeal airway is inserted into a lightly anaesthetised patient?
Vomiting
Laryngospasm
What is the function of a laryngeal mask airway?
Maintains airway but does not protect it
What are the possible anaesthetic causes of an obstructed airway?
Ineffective triple airway maneuver
Airway device mispositioning or kinking
Laryngospasm
What is a laryngospasm and how is it managed?
Forced reflex adduction of the vocal cords
Can result in complete airway obstruction
Requires re-anaesthetising or additional muscle relaxant
Why is aspiration more likely under anaesthetic?
Loss of protective airway reflexes such as gag reflex Foreign material likely to be present in the lower airway such as blood, gastric contents and surgical debris
When is an airway considered to be maintained?
When it is open and unobstructed
How is an airway protected?
With endotracheal intubation
Usually done orally so muscle relaxant required to abolish laryngeal reflexes
