EFFECT OF LOCAL ANESTHETIC DRUG ON RABBIT EYES

Learn [pharmacology practical experiment]

Theory:-                                                    

Local anesthetic affects a limited area of ​​the body and is used for minor incisions, surgical operations.

1. Binding of sodium channels:-                           

Local anesthetics bind to sodium channels in the nerve membrane, blocking the flow of sodium ions.

2. Blocking action potentials:-            

Local anesthetics block the generation of action potentials by blocking the flow of sodium ions.

3. Blocking nerve conduction:-                 

Local anesthetics block the transmission of nerve impulses, resulting in reduced sensation.

Types of local anesthetic drugs

1. Esters:-                                              

   Examples include procaine, chlorprocaine, and tetracaine.

2. Amids:-                                               

   Examples include lidocaine, mepivacaine, and bupivacaine.

Pharmaceuticals

Local anesthetics have the following pharmacokinetic properties:

1. Absorption:-                                                 

   Absorption through blood.

2. Distribution:-                                                

Local anesthetics are distributed throughout the body with high concentrations in the liver and kidneys.

Metabolism:-                                               Local anesthetics are eliminated from the body through a combination of metabolism and excretion.

Factors affecting local anesthetic action.

Several factors can affect the action of local anesthetics including:

1. Concentration:-                                                

The concentration of the local anesthetic can affect its strength and duration of action.

2. pH:-                                                   

The pH of the local anesthetic solution can affect its stability and potency.

3. Temperature:-                                      

The temperature of the local anesthetic solution can affect its strength and duration of action.

4. Presence of vasoconstrictors:-   

The presence of vasoconstrictors such as epinephrine may affect the duration of action of local anesthetics.

Clinical applications                

1. Dental Anesthesia:-                         

   Provide anesthesia for dental procedures.

Skin irritation:-                                    

Provide anesthesia for skin procedures such as biopsies and excisions.

3. Numbness of the eyes:-                           

Local anesthesia is used to provide anesthesia for eye procedures such as cataract surgery.

Start of action:                   

1. Type of Local Anesthetic:-                  

   Different local anesthetics have different onset times.

2. Concentration:-                                              

   High concentrations of local anesthetics have a rapid onset.

3. Route of Administration:-                              

Injectable local anesthetics may have a longer onset than topical anesthetics.

Some approximate onset times for common local anesthetics are:

1. Lidocaine:- 2-5 minutes                                

2. Mepivacaine:- 2-5 minutes                            

3. Bupivacaine:- 5-15 minutes                

4. Tetraquine:- 5-15 minutes                           

Duration of action             

Duration of action of common local anesthetic drugs on rabbit eyes

1. Lidocaine:-30 minutes to 1 hour                 

2. Mepivacaine:- 30 minutes to 1 hour

3. Bupivacaine:- 2-4 hours                

4. Tetraquine:- 2-4 hours                           

5. Procaine:- 15-30 minutes                           

 

Effect on rabbit eyes              

Local anesthetics can have a variety of effects on rabbit eyes including:

*Positive Effects*                    

1. Anesthesia:-                                         

Local anesthetics provide effective anesthesia that allows for pain-free procedures.

2. Stress reduction:-                                      

   Anesthesia can reduce stress and anxiety in rabbits during ocular procedures.

3. Success of improved procedures:-                 

Local anesthetics enable physicians to perform procedures with greater precision and success.

*adverse effects*                      

1. Corneal toxicity:-                                        

High concentrations or prolonged exposure to local anesthetics can cause corneal toxicity that can lead to damage or even blindness.

2. Tear film disruption:-                               

Local anesthetics can disrupt the tear film, causing dry eye and other complications.

   Local anesthetics are metabolized by the liver with some metabolites excreted in the urine.

PROCEDURE:

Here's a step-by-step guide to the procedure for administering local anesthetic drugs to rabbit eyes:

*Pre-Procedure Preparation*

1.Prepare the rabbit:-

Ensure the rabbit is properly restrained and comfortable.

2.Clean and prepare the eye:-

Clean and prepare the eyes.

3.Choose the local anesthetic:-

Select the appropriate local anesthetic drug and concentration based on the procedure and the rabbit's medical history.

*Administration Procedure*

1.Topical administration:-

 Apply a few drops of local anesthetic solution to the eye taking care not to touch the cornea.

2.Wait for onset:-

Wait for the local anesthetic to take effect usually