Pharmacological properties and clinical applications of lidocaine and bupivacaine

Lidocaine, also known as cilocaine, is an amide compound. Its hydrochloride is a white crystalline powder that is easily soluble in water.

It is commonly used in clinical practice for topical anesthesia (2%-4% solution), infiltration anesthesia (solution), conduction anesthesia (with 1%-2% solution) and epidural anesthesia (with 1%-2% solution).Therefore, caution should be exercised when using spinal anesthesia.

Bupivacaine. Also known as hemp caine, it is an amide compound. Its hydrochloride is a white crystalline powder that is easily soluble in water.

This drug has a strong and long-lasting effect on local anesthesia, and is suitable for infiltration anesthesia (solution), conduction anesthesia (with solution), spinal anesthesia (with solution) and epidural anesthesia (with solution).Due to its weak tissue penetration, it is not suitable for topical anesthesia.

Answer]: Inhibition of a small amount of sodium influx involved in the action potential repolarization 2 phase, shortening the APD of Purkinje fibers and ventricular muscle, has a strong effect on depolarization tissues such as ischemic areas, and has a weak effect on atrial muscle; It can reduce the action potential of 4 phases and divide the slope of the bending pole and reduce the excitability.

It is mainly used for ventricular arrhythmias, such as cardiac surgery collapse, cardiac catheterization, acute myocardial infarction, ventricular tachycardia and ventricular fibrillation caused by cardiac glycoside poisoning.

pharmachologic action].

1. At very low concentrations, it can slow down the automaticity of Purkinje fibers and increase the ventricular fibrillation threshold.

2. ** Significant effect on the conduction of Purkinje fibers.

1) conduction is significantly slowed down during myocardial ischemia;

2) When blood K+ decreases, it promotes K+ outflow, causes hyperpolarization, and accelerates conduction.

3. In large doses, conduction is slowed down, and even complete conduction block occurs.

4. Relatively prolonging the effective refractory period: it is beneficial to eliminate the reentry excitation and promote the outflow of 3-phase K+.

Clinical application] is only used for ventricular arrhythmias, and is a safe and effective drug.

1. It is preferred for patients with acute myocardial infarction with premature ventricular contractions, ventricular tachycardia and ventricular fibrillation.

2. Examination caused by organic heart disease, large **, collection of ventricular arrhythmias, such as digitalis poisoning, surgery, especially in critical cases.

In vivo process]1, the first pass is eliminated obviously, and it is not suitable for oral administration.

2. Yizi has a reputation for short-acting drug administration for 20min.

Adverse reactions] are mild.

1) Nervous system reactions, such as dizziness, drowsiness, and convulsions caused by a large number of times.

2) Cardiovascular reaction, a large amount of cardiac depression, BP drop, etc.

The effect of local anesthesia is stronger than that of lidocaine (about 4 times stronger). The time for the solution to cause local anesthesia is generally 4 10 minutes, and the solution has a slightly faster onset of action. The solution plus epinephrine was used for epidural block anesthesia, and the effect could be maintained for 5 hours.

Due to the low concentration in the blood, the accumulation in the body is small, and the duration of action is long, it is a safer long-acting local anesthetic source drug than Shengxin eggplant.