Pharmacology of general anesthetic agents

General anesthetics are drugs that induce a state of controlled unconsciousness, allowing for painless surgical procedures. Their pharmacology involves several key mechanisms:

1. Mechanism of Action: General anesthetics work primarily by enhancing inhibitory neurotransmission (e.g., through GABA receptors) and inhibiting excitatory neurotransmission (e.g., through NMDA receptors). This results in a decrease in neuronal excitability.

2. Types of Agents:

   • Inhalational Agents: Commonly used agents include halothane, isoflurane, and sevoflurane. These are volatile compounds that are absorbed through the lungs and distributed to the brain and other tissues.
   • Intravenous Agents: Examples include propofol, thiopental, and etomidate. These agents induce rapid anesthesia and are often used for the induction of anesthesia.

3. Pharmacokinetics: General anesthetics are characterized by their rapid onset and offset, influenced by their solubility in blood and fat. Lipid-soluble agents can quickly cross the blood-brain barrier, leading to swift effects.

4. Side Effects: Potential adverse effects include cardiovascular and respiratory depression, nausea, and postoperative cognitive dysfunction.

5. Monitoring: Continuous monitoring of vital signs and anesthetic depth is crucial during procedures to ensure patient safety.

Overall, the choice of anesthetic depends on various factors, including the type of surgery, patient health, and specific anesthetic properties.