Acute Pain & Opioid-Free Analgesia (Exam II) Flashcards
What types of somatic pain are there?
- Superficial: skin, SQ, mucous membranes
- Deep: muscles, bones, tendons
What types of visceral pain are there?
- Parietal: sharp, localized organ pain.
- Referred: Cutaneous pain from convergence of visceral and somatic afferent input.
Is chronic nociceptive pain or neuropathic pain more abnormal?
Neuropathic pain
What are some possible cardiac consequences of poorly managed pain? 3
↑ HR
↑ BP
↑ Cardiac workload
What are some possible respiratory consequences of poorly managed pain? 5
- Splinting (resp muscle spasm)
- ↓ VC
- Atelectasis
- Hypoxia
- Pulmonary infection risk
What are some gastrointestinal consequences of poorly managed pain? 1
Ileus
What are some possible renal consequences of poorly managed pain? 2
- Oliguria
- Urine retention
What are some possible coagulative consequences of poorly managed pain? 1
↑ clot risk
What are some possible immunologic consequences of poorly managed pain? 1
Immunosuppression
What are some possible musculoskeletal consequences of poorly managed pain? 2
- Fatigue & weakness
- Limited mobility = clotting
What is the Specificity Theory?
Who came up with it?
Specific sensation w/ its own sensory system independent of touch and other senses - Descartes
What theory linked pain and emotion?
Intensity Theory (Plato)
Where is pain attenuated in the CNS according to gate theory?
Substantia Gelatinosa
The cells in this area function as a gate regulating transmission of impulses to the central nervous system.
What chemicals are released upon tissue injury that mediate pain? 4
- Histamine & Inflammatory Mediators:
- Bradykinin (peptide)
- Prostaglandins (lipids)
- Serotonin
Give an example of first order neurons.
Aδ and C
Where do first order Aδ and C fibers synapse at?
Dorsal Root of the spinal cord
Where do second order neurons synapse at?
Thalamus
What is the name of the process by which noxious stimuli are converted to action potentials?
Transduction
What is the name of the process by which an action potential is conducted through the nervous system?
Transmission
What is the name of the process by which pain transmission is altered along its afferent pathway?
Modulation
What is the name of the process by which painful input is integrated in the somatosensory and limbic cortices of the brain?
Perception
Hyperalgesia is the process by which tissue trauma releases _____ _______ ______ that produced augmented sensitivity to stimuli. 1
local inflammatory mediators
What is primary hyperalgesia?
Augmented sensitivity to painful response.
or
Allodynia-style misinterpretation of non-painful stimuli.
What is secondary hyperalgesia?
Increased neuronal excitability due to glutamate activation of NMDA receptors.
Similar to Remifentanyl where admin without Ketamine (NMDA) will lead to Hyperalgesia
AKA: Medication induced
What opioid will potentiate hyperalgesia?
Remifentanil
What is the treatment for hyperalgesia that was mentioned in lecture?
Ketamine
Differentiate Hyperalgesia and Allodynia.
In graphical form.
Note: Stimulus that does not typically evoke pain, evokes pain. (Allodynia)
With chronic pain, a small painful stimulus can be perceived as a large painful stimulus (Hyperalgesia)
Both are considered a Left Shift in the graphical representation of Pain Sensitization
What is the hallmark “negative” symptom of neuropathy?
numbness
Positive s/s can exist as well (pain, sensitivity, etc.
GI blood flow and motility increase as we age. T/F?
False.
Gastric acid secretion ______ as we age thus _______ gastric pH.
decreases; increasing
What effect does aging have on nutrient absorption in the GI tract?
Minimal
What occurs to muscle and fat mass as a patient ages?
Muscle decreases while fat increases
A decrease in _______ affects your protein-bound drugs in aging.
albumin
What occurs with hepatic function in the aging patient? 3
- ↓ hepatic blood flow
- ↓ liver mass and metabolic activity
What occurs with renal function due to aging?
- ↓ GFR
- ↓ kidney mass & functioning nephrons
Do opioids or non-opioid analgesics exhibit a ceiling effect?
Non-opioid analgesics
What opioid receptor is responsible for analgesia, respiratory depression, euphoria, and reduced GI motility?
μ receptor
What opioid receptor (when agonized) is responsible for analgesia, dysphoria, psychosis, miosis, and respiratory depression?
Κappa receptor
What opioid receptor causes analgesia alone when bound by an agonist?
Delta
What drug is described by the following organic structure:
Substitution of methyl group for hydroxyl group on #3 carbon of morphine molecule.
Codeine
______ is much more reliably absorbed than morphine.
Codeine
More reliably absorbed orally than morphine
What drug exhibits side effects (without concurrent analgesia) in children?
Why is this?
Codeine
Children lack enzymatic maturity needed to properly break down codeine.
What CYPs metabolize codeine?
CYP2D6 → morphine
CYP3A4 → norcodeine
Codeine metabolism is variable due to more than ____ polymorphisms resulting in analgesic variability.
50
What is the adult dose and max of codeine?
15 - 60 mg q4
360mg max per day
What is the pediatric dose and max of codeine?
0.5 - 1 mg/kg/dose
60mg max per day <— what? Literally 1 adult dose.
60mg of codeine (maximal dose) is equivalent to how much aspirin?
650mg
What drugs does codeine have interactions with? 3
Opioids, EtOH, and Anticholinergics
What drug is described by the following?
Tramadol
Where does the + enantiomer of tramadol have affinity and what does it do? 4
Centrally acting opioid agonist:
- μ → moderate affinity
- K & δ → weak affinity
- Opposes serotonin reuptake
What does the - entantiomer of tramadol do? 2
- Inhibits NE reuptake
- Stimulates α2 receptors