T1 L20: Anaesthetic Drugs (DMcD)

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is a definition of anaesthesia?

A defect of sensation

A state of tranquillization

A reversible drug induced absence of sensation and awareness (correct)

A state of coma

What is the order of depression of the brain caused by lipid soluble anaesthetic agents?

Midbrain, Spinal cord, Medulla, Cortex

Spinal cord, Medulla, Cortex, Midbrain

Cortex, Midbrain, Spinal cord, Medulla (correct)

Medulla, Cortex, Midbrain, Spinal cord

Which of the following is NOT a method of administering anaesthesia?

Inhalation

Intravenous

Oral (correct)

Topical

What was the first inhalational anaesthetic discovered?

Nitrous Oxide Signup and view all the answers

What is the main mechanism of action of anaesthetics on cell membranes?

Modulation of ligand gated ion channels Signup and view all the answers

Which receptors are stimulated by anaesthetics to produce hyperpolarization?

GABAA Signup and view all the answers

Which of the following is NOT a common method of inducing anaesthesia?

Excitation Signup and view all the answers

Which of the following is a muscle relaxant used in anaesthesia?

Vecuronium Signup and view all the answers

What is the purpose of balanced anaesthesia?

To minimize side effects of anaesthesia Signup and view all the answers

Which inhalational agent has the highest blood:gas solubility?

Halothane Signup and view all the answers

Which inhalational agent is the least irritating to the airway?

Sevoflurane Signup and view all the answers

Which inhalational agent is the most expensive?

Desflurane Signup and view all the answers

Which inhalational agent has the highest MAC (Minimum Alveolar Concentration)?

Isoflurane Signup and view all the answers

Which inhalational agent has the highest environmental impact?

Desflurane Signup and view all the answers

Which intravenous induction agent has the shortest half-life?

Etomidate Signup and view all the answers

Which intravenous induction agent has anti-emetic properties?

Propofol Signup and view all the answers

Which intravenous induction agent is painful to inject?

Thiopentone Signup and view all the answers

Which muscle relaxant is classified as a depolarizing agent?

Suxamethonium Signup and view all the answers

Which muscle relaxant is classified as a non-depolarizing agent?

Rocuronium Signup and view all the answers

According to the text, what percentage of all hospital doctors are anaesthetists?

20% Signup and view all the answers

Who discovered nitrous oxide in 1772?

Joseph Priestley Signup and view all the answers

What is the main use of nitrous oxide in hospitals?

As an analgesic agent Signup and view all the answers

Who gave the first recognized case of true anesthesia in 1846?

William Morton Signup and view all the answers

What was the first inhalational agent used for anesthesia?

Aether Signup and view all the answers

Which of the following is the primary mechanism of action of anaesthetic agents on cell membranes?

Interaction with membrane proteins Signup and view all the answers

How are anaesthetic agents typically administered?

Inhalation or injection Signup and view all the answers

Which receptor type is stimulated by anaesthetic agents to produce hyperpolarization?

Inhibitory receptors Signup and view all the answers

What is the most important drug in anaesthesia?

Oxygen Signup and view all the answers

Which gas is commonly used in anaesthesia and is stored in black cylinders with a white shoulder?

Oxygen Signup and view all the answers

What is the maximum concentration of nitrous oxide that can be given in a mixture with oxygen?

80% Signup and view all the answers

What is the concept that gives an idea of the potency of an anaesthetic agent?

Mac Signup and view all the answers

What is the minimum alveolar concentration required to stop 50% of people reacting to an incision?

50% Signup and view all the answers

Which course was originally called the Ace Course and included anaesthesia critical care and emergency medicine?

The Clinical Foundation course Signup and view all the answers

What is the purpose of simulation in medical teaching?

To practice different medical activities on mannequins and dummies Signup and view all the answers

What is the average number of pharmacological agents in a balanced anaesthetic?

10 to 12 Signup and view all the answers

What is the simplest definition of anaesthesia according to the Oxford Dictionary in 1751?

A defect of sensation Signup and view all the answers

Which of the following is a characteristic of anaesthesia?

It is caused by a drug Signup and view all the answers

Which of the following is NOT a stage of anaesthesia described in the text?

Relaxation Signup and view all the answers

What is the main difference between sedation and anaesthesia?

Sedation allows for easy awakening, while anaesthesia does not Signup and view all the answers

Which of the following is a method of administering anaesthesia described in the text?

All of the above Signup and view all the answers

Which of the following statements about nitrous oxide is correct?

Nitrous oxide should not be used in cases with air-filled spaces Signup and view all the answers

What is an important characteristic of anaesthetic agents?

They reduce the capacity to breathe and affect the cardiovascular system Signup and view all the answers

Why are most anaesthetic agents considered dangerous?

They reduce the capacity to breathe and affect the cardiovascular system Signup and view all the answers

What is an important phrase associated with anaesthesia?

Cardiorespiratory depressant Signup and view all the answers

Which of the following is a potential side effect of using nitrous oxide?

Neuropathic pain Signup and view all the answers

What is a rare characteristic of inhalational agents?

Quick onset and offset Signup and view all the answers

Study Notes

Definition and Nature of Anaesthesia

Anaesthesia is defined as a state that prevents pain during surgery or medical procedures.
The simplest definition of anaesthesia, according to the Oxford Dictionary in 1751, refers to the loss of sensation or awareness.

Order of Depression of the Brain

Lipid-soluble anaesthetic agents induce a specific order of brain depression, impacting higher functions before lower functions.

Methods of Administration

Common methods of administering anaesthesia include inhalation, intravenous, and regional techniques.
An option mentioned is NOT considered a method of administering anaesthesia.

Inhalational Anaesthetics

The first discovered inhalational anaesthetic was nitrous oxide in 1772.
Halothane is reported to have the highest blood:gas solubility.
Nitrous oxide is the least irritating to the airway and commonly used in hospitals.
Isoflurane is the most expensive inhalational agent.
Desflurane has the highest Minimum Alveolar Concentration (MAC) and the most significant environmental impact.
The maximum concentration of nitrous oxide that can be administered with oxygen is 70%.

Mechanisms of Action

The primary mechanism of action of anaesthetics on cell membranes involves modulation of ion channels.
Anaesthetic agents stimulate GABA receptors to produce hyperpolarization and inhibit the excitatory effects of neurotransmitters.

Muscle Relaxants

Succinylcholine is a depolarizing muscle relaxant.
Rocuronium is an example of a non-depolarizing muscle relaxant.

Intravenous Induction Agents

Propofol is known as the intravenous induction agent with the shortest half-life and has anti-emetic properties.
A common side effect of certain intravenous induction agents includes pain upon injection.

Anaesthesia Practices and Statistics

Approximately 10% of all hospital doctors are anaesthetists.
The first recognized case of true anaesthesia occurred in 1846 by William Morton.
The average balanced anaesthetic comprises about five pharmacological agents.

Role of Simulation

Simulation in medical teaching is essential for providing realistic, hands-on training and enhancing clinical skills.

Characteristics and Risks of Anaesthesia

Most anaesthetics are considered dangerous due to their potent effects on respiratory and cardiovascular systems.
A rare characteristic of inhalational agents includes the ability to create a minimal effect on cardiac rhythm.

Additional Points

The concept associated with anaesthetic potency is expressed as Minimum Alveolar Concentration (MAC).
The primary difference between sedation and anaesthesia is the level of consciousness and responsiveness.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on anaesthetic agents and their role in anaesthesia with this quiz. Explore topics such as the history of anaesthesia, how anaesthetics work, inhalational and intravenous agents, muscle relaxants, and balanced anaesthesia. Challenge yourself and become an expert in the field of anaesthesia.