General and Local Anesthetics

General and Local Anesthetics

General anesthesia -a state of unconsciousness, analgesia and amnesia, with skeletal muscle relaxation and loss of reflexes.

                                          Classification

1.Inhaled

a.    Volatile liquids

           -ether

                 -enflurane

                 -photorotane

                  -isofluran

b.    Gas

            -ciclopropan

2.Intravenous

a.barbiturates (thiopental, hexenal)

c.     benzodiazepines (midazocalm)

d.    opioids (morphine, fentanyl, remifentanil)

e.     dissociative (ketamine)

f.     phenols (propofol)

Mechanism of action

A lot of theory explains their mechanism of action

1.The protoplasm of neurocellules   coagulates.

2. Metabolism’s inhibition produces a hypoxia of neurocellules.

3. Lipid theory

4. Protein theory

           Stages of anesthesia

1.    Stage I-Analgesia

2.    Stage II- Excitement

3.    Stage III Surgical anesthesia

4.    Stage IV Medullary paralysis

Indications

1.    In surgery (for various operations)

2.    severe angina and infarct

3.    fractures.

Contraindications

1.    hyper sensibility 

2.    The severe disease of liver,

3.    The severe disease of kidney,

4.     The severe disease of  heard,

5.     The respiratory failure

 Side effects:

1.    Allergy

2.    tachycardia

3.    thromboses

4.    depression of the respiratory system and cardiovascular system

5.    hypo secretion of exocrine glands  

   

                                    Local anesthetics:

Is the condition that results when sensory transmission from a local area of the body to the CNS is blocked.

                                     Classification

I.              According to the origin

                     1.naturale-cocaine

                     2.synthetic - tetracaine

                                        - procaine

                                         -lidocaine

                     3.various  -   phenol

                                          diphenylhidramine

II          According to the chemical structure

1.    Derivates of paraaminobenzoical acid

-       procaine

-       tetracaine

-       benzocaine

     III          According to the activity

1.    very active : tetracaine

2.     active:   lidocaine

3.    less active : procaine

     IV          According to the use

1.    With superficial action

-       anesthezine

-        dicaine

-        lidocaine

                              2.   for infiltrative    anesthesia

                                        -      procaine

                               3.  for rahanesthesia

                                        -       sofcaine, lidocaine .

 Mechanism of action:

Local anesthetics block voltage dependent sodium channels and reduce the influx of sodium ions preventing depolarization of the membrane and blocking the conduction of the action potential.

 Local anesthetics activity is strongly PH-dependent, being increased at alkaline PH and vice versa.

 Side effects: 

-tremor

-euphoria

-heard depression

-vasodilatation

-tachycardia

-convulsion

-respiratory depression

-hypotension

-hypersensitivity reaction (allergic, anaphylactic reaction)

    

Astringents

The remedies are used to cure inflammation of skin or mucosa. After application the membrane is formed on the lesion that protects it.

Classification:

1.    Organic astringents (Tanninum)

2.    Unorganic astringents (Plumbi acetas, Alumen)

Adsorbents

Are the remedies that absorb the toxins from the intestine.

 (carbosem, medicas E)

Mucilaginous:

These remedies are used in gastrointestinal inflammation.

Way of administration is per oral.

A membrane is formed on the lesion surface.

The drugs: Mucilago amyli.

Irritating substances:

The drugs excites the receptors of the application area, producing vasodilatation and improves irrigation of tissues.

Drugs: Mentholum,  Oleum Terebinthinae,  Solutio  Ammonii Caustici.