Anaesthetics

Anaesthetics are medications used to induce a state of controlled, temporary loss of sensation or awareness, typically for the purpose of performing surgical procedures or other medical interventions.

Types of Anaesthetics

• Local Anaesthetics: These numb a specific area of the body, such as a tooth or a small region of skin. Examples include lidocaine and benzocaine.
• Regional Anaesthetics: These numb a larger area of the body, such as an arm or leg. Examples include epidural anaesthesia and spinal anaesthesia.
• General Anaesthetics: These induce a state of unconsciousness and are used for more extensive surgical procedures. Examples include inhalational anaesthetics (such as isoflurane and sevoflurane) and intravenous anaesthetics (such as propofol and thiopental).
• Sedatives: These are medications that produce a state of relaxation or drowsiness, but do not necessarily induce unconsciousness. Examples include midazolam and diazepam.

How Anaesthetics Work

Anaesthetics work by interfering with the transmission of nerve impulses in the body. They can act on various sites, including the brain, spinal cord, and peripheral nerves. The exact mechanism of action varies depending on the type of anaesthetic.

Risks and Side Effects

• Common side effects: Nausea, vomiting, dizziness, headache, and sore throat.
• Less common side effects: Allergic reactions, respiratory problems, and cardiac complications.
• Rare but serious side effects: Anaphylaxis, malignant hyperthermia, and permanent nerve damage.

Preparation for Anaesthesia

Before undergoing anaesthesia, patients typically undergo a pre-anaesthetic evaluation, which includes:

• Medical history review
• Physical examination
• Laboratory tests (such as blood work and electrocardiogram)
• Fasting instructions (to reduce the risk of aspiration)

Monitoring During Anaesthesia

During anaesthesia, patients are closely monitored using various devices, including:

• Electrocardiogram (ECG) to monitor heart rate and rhythm
• Blood pressure monitor
• Pulse oximeter to monitor oxygen saturation
• Capnograph to monitor carbon dioxide levels

Recovery from Anaesthesia

After anaesthesia, patients are typically taken to a recovery room where they are monitored for any potential complications. The recovery process may involve:

• Pain management
• Nausea and vomiting control
• Monitoring of vital signs
• Gradual return to consciousness and mobility