Anesthesia Flashcards
Physiology
How the major organs of the body work
Pathophysiology
How disease affect the body
Order of pain processing
- Transduction - thermal, chemical, or mechanical stimuli are converted into an action potential
- Transmission - action potential travels through 1st, 2nd, and 3rd order neurons
- Modulation - inhibition or augmentation of the afferent or efferent pain signals
- Perception - final pathway; integration of painful input into the somatosensory and limbic cortices
Allodynia
A painful response to a normally innocuous stimulus
Hyperalgesia
An increased response to painful stimuli
A 55 year old man has severe pain on gentle touching of the arm. Six months ago, the median nerve was damaged. What is the term that defines this phenomenon?
The question states “gentle,” which can be interpreted as an innocuous stimulus. However, the man is responding to it painfully. This is an example of allodynia
Analgesia definition
It is the absence of pain while conscious. These drugs are painkillers
What type of analgesia are NSAIDs (Nonsteroidal anti-inflammatory drugs)? What enzymes do they normally target? Give 4 examples of NSAIDs
Non-opiate analgesia
They target COX-1 and COX-2 enzymes depending on what the drug is selective for
Ex. Ibuprofen (Advil), Aspirin, Naproxen (Aleve), Steroid
What type of analgesia is Acetaminophen (Paracetamol)? What enzyme do they normally target? Do they have a high or low therapeutic index (TI)?
Non-opiate analgesia
Blocks COX-3 in the brain
They have a high TI. This means that an individual would have to take a lot of pills to feel toxic side effects
MOA of opiate analgesia
- They block neurotransmitter release by inhibiting Ca2+ influx into the presynaptic terminal
- Open K+ channels, which hyperpolarizes neurons and inhibits spike activity
What type of analgesia is Fentanyl? Do they have a high or low TI?
Opiate analgesia - it is a cheap synthetic opioid
It has a low TI - very potent and fast acting
A 35 year old female is 4 days post surgery for motor vehicle accident injury? The surgeon prescribed her Hydromorphone (Dilaudid). While she takes acetaminophen, naproxen and hydromorphone, her brother teases her and says, “Why do you take so many? It’s not good to mix drugs!” Is this true?
No - it is good to approach the injury through multimodal analgesia because pain comes from multiple sources. This gives the drugs a chance to attach multiple pathways, such as COX-1, COX-2, etc.
True or False: Prior to 2013, more people died of heroin overdose than prescription opiates.
False - most overdoses were due to prescribed medication. This is because the Sackler family pushed prescription medicine to patients
True or False: In 2017, more people died of heroin overdose than prescription opiates
True - in 2017, synthetic fentanyl was introduced and laced into heroin → more deaths from heroin that was laced with fentanyl
Definition, example, MOA of local anaesthetic
Anaesthetic that blocks a part of the body (regional anesthesia)
Ex. Lidocaine
MOA: Na+ channel blocker and prevents the propagation of nerve action
