Central Nervous System Pharmacology ( General Anesthetics ).pptx

Central Nervous System Pharmacology General Anesthetics . effect of general anesthesia on CNS, what is Pre Anesthesia.

1. PRESENTED BY : NIBE CHETAN DATTATRAY F.Y.M PHARM ( DEPT OF PHARMACOLOGY ) G ENERAL ANESTHETICS GUIDED BY : DR.S.B.DIGHE HOD PHARMACOLOGY DEPARTMENT

2. INTRODUCTION : Definition : General anesthetics are drugs that induce a reversible loss of consciousness and sensation, typically used during surgery. Purpose: Used for pain management, muscle relaxation, and amnesia during surgery or other invasive medical procedures. Brief History : First use in 1846 (Ether).

3. Ideal Characteristics of General Anesthetics Rapid induction and recovery. Wide margin of safety. Minimal side effects. No toxicity or adverse effects on vital organs.

4. Stages of General Anesthesia Stage I: Analgesia (conscious but pain relief). 2. Stage II: Excitement (unconscious but with reflex activity ). 3. Stage III: Surgical anesthesia (complete loss of consciousness and reflexes). 4. Stage IV: Medullary paralysis (overdose leading to respiratory failure ).

5. Types of General Anesthetics Inhalational: Administered via the respiratory tract. Examples: Nitrous oxide, Halothane, Isoflurane . Intravenous: Administered through IV injection. Examples: Propofol, Ketamine, Thiopental sodium

6. Mechanism of Action Inhalational Anesthetics : Enhance GABA receptor activity, reducing neuronal excitability. Reduce synaptic transmission by inhibiting NMDA receptors. IV Anesthetics : Work by increasing inhibitory neurotransmitter (GABA) action.

7. Inhalational Anesthetics Advantages: Easy to control depth of anesthesia , rapid elimination. Examples:Nitrous Oxide: Safe, weak anesthetics . Isoflurane: Potent, used for maintenance. Intravenous Anesthetics Advantages: Rapid induction, minimal equipment needed. Example:Propofol : Quick onset, widely used. Ketamine: Provides analgesia and sedation.

8. Adverse Effects Nausea and vomiting. Respiratory depression. Cardiovascular instability. Rare: Malignant hyperthermia (triggered by inhalational agents).

9. Clinical Applications Induction and maintenance of anesthesia in surgeries. Used in intensive care units for sedation. Procedural sedation for non-surgical interventions.

10. Advances in General Anesthetics Newer agents with better safety profiles. Targeted drug delivery systems. Use of monitoring systems for depth of anesthesia.

11. Conclusion General anesthetics play a crucial role in modern medicine. Selection depends on patient condition and procedure requirements. .Continuous research is improving safety and efficacy.