What is represented by Stage 2 in the image?
A. Stage of Disorientation
C. Stage of Analgesia
Ans: B. Stage of Excitement.
Guedel’s Stages of Anesthesia Stages of Anesthesia is shown in the image.
Stages of Anaesthesia:
- Guedel described four stages of ether anesthesia during the III stage into 4 planes.
- With faster-acting gas, these clear-cut stages are not seen nowadays as induction with these agents is too fast.
1. Stage I / Stage of analgesia:
- Extends from the beginning of anesthetic inhalation to the loss of consciousness.
2. Stage 2 / Stage of delirium or excitement:
- From the loss of consciousness to the beginning of regular respiration.
- There is roving eyeball (maximum movement of the eye).
- The pupil is partially dilated. Eyelash reflex is lost→ First reflex to be lost. However eyelid reflex remains present.
3. Stage 3 / Stage of surgical anesthesia:
- From the beginning of regular respiration to the cessation of spontaneous breathing.
- Most surgeries are done at this stage.
- It is divided into 4 planes:
- Plane I:
- From the beginning of the regular respiration to the cessation of eye movement.
- There is a roving eyeball.
- Eyelid reflex is lost. This plane ends when eyeball becomes fixed.
- Pupil size is normal.
- Plane II:
- From the cessation of eye movement to respiratory Paresis.
- The eyeball is fixed.
- There is a loss of corneal reflex.
- Pupil starts dilating (1/2 dilated).
- Plane III:
- From respiratory paresis to respiratory paralysis. Pupil 3/4 dilated. Swallowing reflex and laryngeal reflexes are lost.
- Plane IV:
- The pupil is fully dilated.
- Carinal reflex (Cough reflex) is lost → Lost reflcx to be lost.
- Lacrimation is present in plane II & In and absent in Plane III, IV.
4. Stage 4 / Stage of medullary paralysis:
- There are respiratory arrest and apnea.
- The pupil is fully dilated & fixed.
- During recovery, the return of reflexes is in opposite sequence, i.e., first to come is carinal reflex and last is eyelash.
- So theoretically it is a cough which should come first but swallowing comes first than coughing because coughing also requires diaphragm and respiratory muscles effort.