Introduction to Anaesthesia Flashcards
What is Anaesthesia?
Greek for “loss of sensation”… with or without loss of consciousness.
When under anaesthesia, you can’t move, form memories, or feel pain.
What does the ‘triad of anaesthesia’ consist of?
Hypnosis - Unconscious element
Analgesia - Pain relief element
Muscle relaxation - Paralysis
True or False?
GA means the patient is unconscious
TRUE
How is GA administered?
Either intravenous (IV) drugs called induction agents e.g. Propofol or anaesthetic gasses (Volatile agents)
Local Anaesthesia
- Administration
- Use
Injected into the tissue to numb the specific location requiring minor surgery and post-operative pain relief.
Nerve Block
- Administration
- Use
Infiltrated into deeper nerves and used to numb larger areas than LA
Regional Anaesthesia
- Administration
- Use
- Benefit
- Patient awareness
- A local anaesthetic is injected in a specific region of the body, leading to numbness or pain relief for deeper operations where more extensive numbness is needed
- Great at reducing post-operative pain.
- Patient is awake or sedated
Spinal Anaesthesia
- Administration region
- Direction of effect
- Primary uses
Injected into the ‘sub-arachnoid space’ in the spine and numbs from the inject site down
Primarily used for:
- Caesarean sections
- Joint replacements
Epidural Anaesthesia
- Administration equiptment and region
- Primary uses
A small catheter is inserted into the epidural space in the spine
Continuous infusion of local anaesthetic is administered down the catheter
Primarily used for:
- Post operative Pain Relief
- Caesarean sections following a failure to progress with natural delivery
Sedation
- Medication effect
- Patient awareness
Medicine that makes you feel sleepy and relaxes you both physically and mentally; it’s sometimes used to keep you calm during less invasive but painful and unpleasant procedures
Patient is semi-conscious
Which organisation published the guidelines for checking an anaesthetic machine?
AAGBI - The Association of Anaesthetists of Great Britain & Ireland 2012
Which items of monitoring make up the minimum required monitoring for a patient having a general anaesthetic?
1) Pulse oximeter - SpO2
2) Non-Invasive Blood Pressure - NIBP
3) ECG
4) Temperature
5) Capnography for breathing analysis
6) Peripheral Nerve Stimulator (if neuromuscular blocking drugs used)
Induction agents are identified using…
Yellow labels
Name four induction agents
Propofol
Ketamine
Thiopental Sodium
Etomidate
Propofol
Emulsion containing 1% propofol in a lipid medium
Can be painful on injection
Sometimes used with lidocaine (LA) added
Dose – 1-2.5 mg/kg
Onset time – 30 seconds Offset time – 3-7 minutes
Metabolised by the liver
Causes hypnosis
Side effects – hypotension, bradycardia, respiratory depressant, reduced sensitivity of the upper airway
Consider egg allergy
Gas induction is preferred in which circumstances?
- Paediatrics
- IV Drug user
- Needle-phobic
- Stridor
Onset is slower – 30 seconds - 2 minutes
Once the patient has been induced, intravenous access will be established immediately
Airway equipment for GA
- Endotracheal tube
- Laryngeal Mask
- Facemask
Name three volatile gases
- Sevoflurane (yellow)
- Isoflurane (purple)
- Desflurane (blue)
What drug is given to reverse the effects of muscle relaxant?
Neostigmine
Which gas is used as a carrier gas?
Nitrous oxide
Reversal and Emergence from Anaesthesia
1) Confirm that neuromuscular function is adequate
2) Discontinue anaesthetic drugs and administer 100 % oxygen
3) Suction the airway carefully to remove accumulated secretions and other debris
4) Ensure that the patient is breathing adequately
5) Place the patient in a suitable recovery position
6) Assess the patient’s wakefulness, and ability to maintain and protect an airway
