Question 1

Which of the following routes of administration has the highest rate of systemic absorption of local anaesthetic agents?&#10;A) Epidural administration&#10;B) Intercostal administration&#10;C) Subcutaneous administration&#10;D) Brachial plexus administration

Accepted Answer

Intercostal administration of local anaesthetic agents has the highest rate of systemic absorption due to the rich vascular supply of the intercostal spaces, which facilitates rapid uptake into the bloodstream.

Question 2

Which of the following local anaesthetics has a relatively long duration of action?&#10;A) Procaine&#10;B) Lignocaine&#10;C) Bupivacaine&#10;D) Mepivacaine

Accepted Answer

Bupivacaine has a long duration of action compared to the other local anaesthetics listed, as it has a slower onset of action and is more lipophilic, allowing it to stay in the tissues for longer periods of time.

Question 3

The mechanism of action of the local anaesthetics is to impede the movement of which ion through its membrane channels?&#10;A) Calcium&#10;B) Potassium&#10;C) Sodium&#10;D) GABA

Accepted Answer

Local anesthetics work by blocking sodium channels in nerve cell membranes, preventing the influx of sodium ions into the cell. This inhibits the depolarization and propagation of nerve impulses, leading to local anesthesia. Calcium, potassium, and GABA are not directly involved in this process.

Deck 43: Local Anesthesia