Signs and Stages of Anesthesia

Question 1

Stage 1

Answer 1

The time between a normal waking state and the loss of consciousness due to an anesthetic

• Mild analgesia here
• Subdivided into 3 planes:
  1: No amnesia or analgesia
  2: Total amnesia and partial analgesia
  3: Total amnesia and total analgesia

Question 2

Stage 2

Answer 2

Associated with loss of awareness and recall, undesired effects of cardiovascular instability, excitation, dysconjugate ocular movements, and emesis

• From loss of consciousness to onset of automatic rhythmicity of vital signs
• Response to stimulation is exaggerated and violent

Question 3

Stage 3

Answer 3

Surgical anesthesia, movement in response to pain is suppressed, divided into 4 planes
-From end of stage 2 to cessation of respiration

Question 4

Stage 4

Answer 4

Associated with cessation of respiration and medullary cardiac reflexes, may lead to death

• All reflexes are absent
• Complete muscle relaxation
• Pupils dilated/fixed

Question 5

Order of loss of reflexes on induction

Answer 5

Swallowing, right at beginning of stage 3, then eyelid -> corneal -> coughing -> secretion -> light

Question 6

3 phases of emergence

Answer 6

1
-Cessation of anesthetic drugs
-Reversal of muscle relaxant
-Apnea -> irregular breathing -> regular breathing
2
-Increased HR/BP, autonomic responsiveness
-Response to painful stimuli
-Salivation, tearing, grimacing, swallowing, coughing
-Extubation is possible
3
-Eye opening
-Response to some oral commands
-Extubation possible