What determines duration of action of local anesthetic?

Local anesthetics vary in their duration of action due primarily to differences in their affinity for protein. Like most drugs, local anesthetics reversibly bind to plasma proteins while circulating in the bloodstream.

How are local anesthetics classified?

Local anaesthetics are categorised into two different classes based on their structure: para-aminobenzoic acid (PABA)–based anaesthetics known as esters and non-PABA-based anaesthetics are termed amide local anaesthetics [1].

Which local anesthetics has the longest duration of action?

Bupivacaine has the greatest percent protein binding and is the longest acting of local anesthetics available in dental cartridges. The clinical performance of local anesthetics correlates with 4 principal characteristics or properties that are summarized in Table 1.

Which anaesthetic has shorter duration of action?

Greater vasodilator activity of a local anesthetic leads to faster absorption and, thus, shorter duration of action.

What are the 4 types of anesthesia?

There are four main categories of anesthesia used during surgery and other procedures: general anesthesia, regional anesthesia, sedation (sometimes called “monitored anesthesia care”), and local anesthesia. Sometimes patients may choose which type of anesthesia will be used.

What are the 3 types of anesthesia?

Types of Anesthesia
  • Local Anesthesia. Local anesthesia is an anesthetic agent given to temporarily stop the sense of pain in a particular area of the body. …
  • Regional Anesthesia. Regional anesthesia is used to numb only the portion of the body that will undergo the surgery. …
  • General Anesthesia.

What is the duration of action of lidocaine?

Lidocaine is known to have an onset <2 min, a duration of 1 h to 2 h, and a maximum dose of 5 mg/kg, which improves to an onset <2 min, a duration of 2 h to 6 h and toxicity of 7mg/kg with the addition of epinephrine (6,7).

Which local anesthetic has the shortest duration?

Lidocaine demonstrated the shortest mean onset of anesthesia (3.1 min) and bupivacaine the longest (7.6 min). Lidocaine also demonstrated the shortest mean duration of anesthesia (1.8 h) and ropivacaine the longest mean duration (21.5 h).

What lasts longer bupivacaine or lidocaine?

However its effects only last up to 2 hours, without epinephrine, and 3 hours, with epinephrine. On the other hand, Bupivacaine, has a slower onset of action (about 5-10 minutes after injection) but its effects last much longer, for about 4-8 hours.

What are the characteristics of local anesthetic?

The functional characteristics of local anesthetics are determined by the dissociation constant (pKa), lipid solubility, and protein binding. The pKa is the pH at which a solution of local anesthetic is in equi- librium, with half in the neutral base (salt) and half in the ionized state (cation).

What are local anesthetic properties?

Local anesthesia is the temporary loss of sensation or pain in one part of the body produced by a topically applied or injected agent without depressing the level of consciousness. Dental anesthetics fall into two groups: esters (procaine, benzocaine) and amides (lidocaine, mepivacaine, prilocaine and articaine).

What is local anesthetic?

Local anesthesia, also called local anesthetic, is usually a one-time injection of medicine that numbs a small area of the body. It is used for procedures such as performing a skin biopsy or breast biopsy, repairing a broken bone, or stitching a deep cut.

What is SAR of local anesthetics?

In terms of drugs structure–activity relationship (SAR), the chemical structure of local anesthetics usually consists of three basic skeleton parts, a lipophilic aromatic ring, intermediate connecting functional group and hydrophilic amine group.

What are the 3 examples of local anesthesia?

What Are Types of Local Anesthesia?
  • ‌Local application. You can apply local anesthetic ointment to open sores or mouth ulcers. …
  • Local injection. Your doctor injects a local anesthetic drug under the skin or deeper. …
  • ‌Nerve blocks.

What is the mechanism of action of local anesthetics?

Mechanism of action of local anesthetics — LAs reversibly inhibit nerve transmission by binding voltage-gated sodium channels (Nav) in the nerve plasma membrane. Nav channels are integral membrane proteins, anchored in the plasma membrane.

What was the first local anesthetic?

As suggested by his friend Sigmund Freud, descriptions of the properties of the coca prompted the Austrian Koller to perform in 1884 the first clinical operation under local anesthesia, by administration of cocaine on the eye.

What are the 6 types of anesthesia?

The Different Kinds of Anesthesia
  • There are different types of anesthetics that may be used for your surgery. …
  • General Anesthesia. …
  • Regional Anesthesiology. …
  • Combined General with Epidural Anesthesia. …
  • Monitored Anesthesia Care with Conscious Sedation.

What is the most commonly used local anesthetic?

Lidocaine is the most common local anesthetic, but doctors and anesthetists use different drugs for different purposes. Bupivacaine is more suitable for longer procedures, but it can be more painful than other drugs during administration.