7. STAGES OF ANAESTHESIA
Using volatile agents specially, ether.
7.1 FIRST STAGE
This is the stage of analgesia starts from the beginning of
induction to the point where there is loss of consciousness.
* It is also referred to a stage of disorientation
7.2 SECOND STAGE
Stage of excitement starts at the loss of consciousness and
prevails till the onset of automatic breathing.
* The patient demonstrates struggling breath holding,
vomiting, coughing, swallowing.
* These various reflex activities can be minimised by
adequate pre-medication and psychological preparation of
the patient.
* On recovery from anaesthesia,patient may demonstrate
delirium in this stage.
7.3 THIRD STAGE (Surgical Anaesthesia)
The onset of this stage is indicated by the observation of
automatic respiration and goes on till the stage of respiratory
paralysis and it is divided into four planes.
Plane 1: Starts with the onset of automatic respiration to
the cessation of eye ball movements.
Plane 2: Starts from the cessation of eye ball movements to
commencement of intercostal paralysis.
Plane 3: Starts with the commencement of intercostal
paralysis to its completion.
Plane 4: Starts with complete inter costal pralysis and ends
with diaphragmatic paralysis.
7.4 FOURTH STAGE (Overdosages)
Fourth stage starts with the beginning of diaphragmatic paralysis
apnea goes on to death.All reflex activity is lost,and the pupils
are widely dilated.
OBJECTIVE
It would be seen that by constant observation of respiration and
ocular movements.
* pupils, eyes-reflexes laryngael and phyarngael reflexes.
* respiratory responses to skin stimulation and lastly
muscular tone.
* Patient can be kept in the surgical stage of anaesthesia
