Pain Management Flashcards
Why is pain management important in the post op patient? This systemically!
WITHOUT addressing the pain:
- increased catecholamines, hyperglycemia, high blood pressure, HR, vasoconstriction, decreased ventilation, increased infection, decreased GI motility, urinary retention, decreased immune response, weakness. fatigue and atrophy of muscles. DECREASED PT satisfaction. Increased anxiety, fear, anger and suffering.
Which fibers are responsible for “second pain” such as burning, aching or throbbing?
C fibers: these are unmyelinated and activated by chemical, thermal or mechanical stimuli.
In comparison, alpha fibers are only initiate pain from mechanical or thermal. They are myelinated and and cause FIRST pain = sharp, brief and localized pertaining to a specific area.
What NT inhibit pain?
GABA, glycine, serotonin and adenosine.
Glutamate and asparate are excitatory factors.
What is peripheral sensitization vs central sensitization?
Peripheral: localized, inflammation… which in an unbalanced state can lead to transmission of pain. This can lead to greater transduction and transmission de to lower thresholds.
Central: also an imbalance of the modulation attack point. there is a disproportionate excitatory signal leading to noxious stimuli. This is driven by peripheral signals, .
** often cause cycle of inflammation and further sensitization to pain.
What is allydonia?
People perceive a non-noxious stimuli to be noxious.
Light tough may be registered by NMDA receptors to be painful.
Why is preemptive pain management so important?
It can reduce the activation of peripheral or central sensitization. Also decreasing the time until pain is sensed as well as decreasing total narc usage.
*** example: local nerve blocks prior to surgery can help with this principle.
What is the proper dose for Lorezepam pre-op for a patient with anxiety?
other Pre- op doses for:
- opioid:
- non opioid:
- Gabapentin
- ketamine
Lorezepam: 2-4mg PO
other Pre- op doses for:
- opioid: Oxycontin (10-20mg PO) or morphine (1-4mg IV)
- non opioid: Celecoxib (200-400mg PO), acetominophen (1000 mg PO).
- Gabapentin: Ca blocker (300-1200 mg PO)
- ketamine: NMDA a blocker (1 mg/kg IV)
What is the GOLD standard for post op pain management
opioids: act to modulate and attack perception points. Increasing the inhibitory signal to dorsal horn of spinalthalamic tract. They prevent the release of excitatory NT. Also act on limbic system to control the emotional response to pain.
What are common side effects of opioids?
nausea, constipation, sedation, seizures, allodynia, opioid induced hyperalgesia, and dependence.
Why are COX 2 inhibitors safer in patients? What is the common drug in this category?
Celecoxib: this can be safer in order to prevent platelet modification and reduce potential GI effects.
All NSAIDS are able to have antipyretic, analgesic and anti-inflammatory effects due to inhibition of prostaglandin synthesis.
How are Ca channel blockers used in pain management?
These are inhibit excitatory signals and stops the mechanisms of pain processing. These are used as an adjuvant to opioids.
Gabapentin often used for seizures, is also proven to have analgesic properties and often used in chronic pain and pre-op pain.
Why are pre- op local nerve block so important?
They prevent noxious stimuli from reaching the spinal cord before any surgery is performed. Modulation nor central sensitization will not occur because signal does not reach the dorsal horn.
Bupivicaine ( marcaine) is long acting and superior in this circumstance!
What are common medications given with a VAS 1-4?
VAS 5-6?
VAS 7-10?
VAS 1-4: acetominophen, aspirin, NSAIDS, other adjuvants.
VAS 5-6: hydrocodone, oxycodone, tramadol, nonopioid analgesics, adjuvants.
VAS 7-10: methadone, fentanyl, hydromorphone, nonopioid analgesics, adjuvants.
