Stage of anesthesia

pedogogy

1. G ood morning

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

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. I ntroduction :

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

6. H istory

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 Stage I- Stage of Analgesia

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 Stage II – Stage of Excitement

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

11. 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

12. 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. Stage IV- Stage of Medullary Paralysis

13. T hank you