Week 2 - Anaesthesia & Pain Flashcards
What is general anaesthetic?
Reversible unconsciousness with analgesia, amnesia, muscle relaxation and depression of reflexes
What is sedation and analgesia?
Provides sedation, analgesia and amnesia but consciousness is still maintained
What is local anaesthetic?
Direct administration of an agent to induce absence of pain in a part of the body without depression of consciousness
What type of applications are local anaesthetics?
- Topical
- Spinal and epidural
- Nerve block
- Infiltration
- Intravenous regional
What is the half life of Alfentanil?
extremely short
What is the half life of Fentanyl?
Short half life - 30 - 60 minutes
What is the half life of Morphine?
30-60 minutes
Nociception?
Perception of pain
Nociceptors
Pain receptors. Bare nerve endings in skin, muscle, joints, arteries
Pain threshold
- Point at which the stimulus is perceived as pain. The entry, where you start to feel the pain
Perceptual dominance
Pain from one area can be overridden by pain in a different area
Pain tolerance
how long you can stand the pain for
Acute pain
Sudden onset. Less than 3 months
Acute somatic
- Arises from connective tissue, muscle, bone and skin
Acute Visceral
Pain in the internal organs and abdomen
Referred pain
Pain that is present in area removed or distant from point of origin
Chronic pain
Longer than 3 months. Dull and persistent.
Nociceptive pain
normal pain feeling
Psychogenic pain
Psychological, psychiatric or psychosocial in origin
What are the most popular drugs for sedation?
Benzodiazepine
Midazolam
The most popular local anaesthetics?
Lignocaine
Bupivacaine
Specificity Theory
Amount of pain is related to the amount of tissue injury
Gate Theory
Developed to explain the complexities of the pain phenomenon
Opiod Reversal
Naloxone.
Antagonist that competitively displaces opioid analgesics from their receptor sites
