pedogogy

2. Presented By :
Dr Farooque Siddiqui
Oral & Maxillofacial Resident

3. In administering an anesthesia
Signpost
Guides in determination of depth of anesthesia
 Guedel describe depth of anaesthesia by dividing it
into stages and planes.

4.  Guedel’s criteria based on :
 Respiration
 Eyeball movement
 Presence or absence of various reflexes
 Gillespie added other criteria
 Secretion of tears
 Response to skin incision
 Evaluation of pharyngeal &
laryngeal reflexes

5.  Stages were first described for ether anesthesia
 Can be used with modification for all agents
 Can be recognized during both induction & recovery

7.  Starts from beginning of anaesthetic inhalation and
lasts up to the loss of consciousness.
 Pain is progressively abolished.
 Patient remains conscious, can hear and see, and feels
a dream like state

8.  Reflexes and respiration remain normal.
 Some minor operations can be carried out during this
stage
 But it is difficult to maintain
 Therefore use is limited to short procedures

9.  Stage starts from loss of consciousness upto gain of
rhythmical respiration
 Respiration – Irregular and large in volume
 Heart rate and BP raises
 Pupils – Large and divergent
 Muscle tone increased – jaw may be tight
 Patient may shout or struggle
 Involuntary micturation , or defecation

11.  Extends from onset of regular respiration to cessation of
spontaneous breathing.
 This has been divided into 4 planes:
o Plane 1- Roving eyeballs.
o This plane ends when eyes become fixed.
o Plane 2- Loss of corneal and laryngeal reflexes.
o Plane 3- Pupil starts dilating and light reflex is lost.
o Plane 4- Intercostal paralysis
Shallow abdominal respiration
Dilated pupil.

12.  As anaesthesia passes to deeper planes
 Progressively-muscle tone decreases
 BP falls
 Heart Rate increases with weak pulse
 Respiration decreases in depth and later in frequency

13.  There is cessation of breathing leading to failure of
circulation and death.
 Pupil is widely dilated
 Muscles are totally flabby
 Pulse is thready or imperceptible
 BP is very low.