Pain Flashcards
what sensations are associated with Epicritic sensations
light touch
pressure
proprioception
temperature discrimination
how are epicritic sensations characterized
what type of threshold receptors
and conducted by what nerve fibers
are characterized by low-threshold receptors and are generally conducted by large myelinated nerve fibers.
what receptors detect protopathic sensations
high threshold receptors
what nerve fibers conduct protopathic sensations
conducted by smaller, lightly myelinated (alpha-delta) and unmyelinated (C) nerve fibers.
where are third order neurons located
located in the thalamus
where do third order neurons send fibers
to somatosensory areas I and II in the post central gyrus of the parietal cortex and the superior wall of the sylvan fissure respectively
Spino-mesencephalic tract
may be important in activating anti-nociceptive, descending pathways because it has some projections to the peri-aqueductal gray
the cornea and tooth pulp are unique- as they are innervated by what fibers
Adelta
C fibers
how sensitive is visceral organ tissue
insensitive tissues
what type of nociceptors do visceral organs contain
silent nociceptors
most other organs (intestine ) are innervated by what type of nociceptors
polymodal nociceptors
what do polymodal nociceptors respond to
smooth muscle spasm, ischemia and inflammation
what do polymodal receptors not respond to
cutting, burning, or crushing that occurs during surgery
Primary hyperalgesia
exaggerated response to pain at the site of injury
Secondary hyperalgesia:
increased pain response evoked by stimuli outside the area of injury…Release of Substance P
Secondary hyperalgesia -skin presentation
has red flushing, local tissue edema, and sensitization to noxious stimuli. Does not have skin denervation.
peripheral sensitization in relation to primary hyperalgesia
of polymodal C fibers & high-threshold mechanoreceptors that leads to primary hyperalgesia
what is the Wong-baker FACES scale who is it best used for?
Designed for children >3yr, useful for those populations who have difficulty communicating
Various faces on the graph (smiling = no pain; to extremely unhappy = worst possible pain) describe the pain
Endocrine effects: Stress increases
catabolic hormones (catecholamines, cortisol, and glucagon
Endocrine effects: Stress decrease what hormones
anabolic hormones (insulin and testosterone)
Hematological effects: Stress mediated increases
platelet adhesiveness, reduced fibrinolysis, and hypercoagulability
define Entrapment syndromes
Are syndromes caused by neural compression wherever a nerve comes through an anatomically narrowed passage, and can involve sensory, motor, or mixed nerves
how is entrapment syndrome diagnosis confirmed
Diagnosis is confirmed by electromyography and nerve conduction studies
Myofascial pain
Syndromes characterized by aching muscle pain, spasms, stiffness, weakness, and occasionally autonomic dysfunction. Patients develop discrete “trigger points” of tenderness in one or more muscles or connective tissues. Roppy bands over trigger points
how is Fibromyalgia diagnosed
diagnosis is by rule out.
fibromyalgia- widespread pain index score?
symptoms severity scale score
7 or higher (or 3-6) with…
5 or higher (9 or higher)
- at least 3 mos
- another d/o not present to otherwise explain the pain
medications approved by FDA for fibromyalgia
pregabalin (Lyrica), duloxetine (Cymbalta), and milnacipran (Savella).
what medications are contraindicated in firbomyalgia (google)
Pure mu-opioid receptor agonists, such as codeine, fentanyl and oxycodone, are contraindicated
90% of disc herniations occur at what levels
L5-S1
or
L4-L5
what is Ankylosing spondylitis
a form of arthritis
what is ankylosing spondylitis associated with
familial disorder associated with histocomptability antigen HLA -B27
who is ankylosing spondylitis usually seen in
low back pain with early morning stiffness in YOUNG patients usually MALE.
how is ankylosing spondylitis diagnosed
radiographic evidence of sacroiliitis present- progression develops bamboo like radiographic appearance.
Diabetic neuropathy
• MOST COMMON neuropathic pain in practice and is a major cause of morbidity
• MOST common syndrome is peripheral polyneuropathy
symmetric numbness (“stocking and glove”)
Tension headache:
Described as tight bandlike pain or discomfort that is often associated with tightness in the neck muscles
where is tension headache usually located on the head
is it bilateral or unilateral
May be frontal, temporal, or occipital
more often bilateral than unilateral
Cluster headaches are classically found where
unilateral and periorbital.
what is the pattern of occurrence for cluster headaches
1-3 attacks/day in a 4-8week period.
how long do cluster headache episodes last
30-120 min
how are cluster headaches pain described
Burning or drilling sensation that may awaken the patient from sleep
trigeminal neuralgia is known as
tic douloureux
nociceptive pain
cause by activation or sensitization of peripheral nociceptors that transduce noxious sitmuli
neuropathic pain
is a resul of injury or acquired abnormalities of peripheral or central neural structures
Acute pain
is caused by noxious stimulation due to injury, a disease process or abnormal function of a muscle or viscera. It is usually nociceptive, which serves to detect, local and limit tissue damage.
Somatic Pain
superficial
how is it characterized?
- Superficial somatic pain is due to nociceptive input arising from skin, subcutaneous tissue, and mucous membranes
- (characterized well localize, sharp, pricking, throbbing, or burning sensation);
Chronic pain
is pain that persists beyond the usual course of an acute disease or after a reasonable time for healing to occur. This healing can vary from 1 to 6 months. Chronic pain may be nociceptive, neuropathic or mixed
the distinguishing factor of chronic pain-
A distinguishing factor of chronic pain is that psychological mechanisms or environmental factors frequently play a major role
first order neurons
majority of neurons send the proximal end of their axons into the spinal cord via the dorsal spinal root at each cervical thoracic lumbar and sacral level
second order neurons
may ascend or descend one to three spinal segments in lissauer tract before synapsing with second order neurons
they snaps with second order neurons in the grey matter of the ipsilateral dorsal horn.
the spinothalamic tract
classically considered the major pain pathway.
what is Classically considered the major pain pathway
The spinothalamic tract
The spinothalamic tract- where is it
It lies anterolaterally in the white matter of the spinal cord.
it is an ascending tract
Acute pain
Acute pain is typically associated with a neuroendocrine stress response that is proportional to
pain intensity
CV effects:
hypertension,
tachycardia,
enhanced myocardial irritability,
increased systemic vascular resistance.
Cardiac output increases in most normal patients but may decrease in patients with compromised ventricular function. Because of the increase in myocardial oxygen demand, pain can worsen or precipitate myocardial ischemia
Respiratory effects:
increase 02 consumption increase c02 production increase minute ventilation increase WOB reduced tidal volume atelectasis shunting reduced vital capacity reduced coughing
Facet syndrome
they “SERVE THE NERVE ROOT”
injury to the facet joint can compress the spinal nerve the exits the respective intervertebral foramen - causing pain and muscle spasm along the associated dermatome
(apex)
Spinal stenosis- is a disease seen with what age group
advancing age
spondylolisthesis
displacement anteriorly of one vertebral body on the next d/t disruption of the posterior elements, usually the pars interarticularis
spondyloptosis
Subluxation of one vertebral body on another resulting in one body in front of the next.
what is the preferred corticosteroid for injection. in procedures involving relatively vascular areas, such as head and neck region.
dexamethasone
Neuralgia
Pain in the distribution of a nerve or a group of nerves -
Sciatic, neuropathy, diabetes, chicken pox (shingles in adults)
Radiculopathy
Functional abnormality of one or more nerve roots
Transduction
The event whereby noxious thermal, chemical, or mechanical stimuli are converted into action potential
Anesthesia
ABSENCE OF ALL PAIN SENSATION
Allodynia
Perception of an ordinarily non-noxious stimulus as pain
-Something that causes pain that wouldn’t normally cause pain!
does the brain have nociceptors
lack nociceptors totally
does the brain meningeal coverings have nociceptors
Yes
visceral afferent fibers travel and enter the spinal cord between
T1 and L2
nociceptive C fibers from the trachea, larynx, and esophagus travel with ____nerve to enter the nucleus solarium in the brain stem .
vagus
excitatory amino acids
glutamate and asparate
excitatory neuropeptides
substance P and calcitonin gene related peptide.
inhibitory amino acids
glycine and GABA
coccydynia
result from trauma to coccyx or surrounding ligaments
Piriformis syndrome –
pain in buttock, numbness and tingling in sciatic nerve
Degenerative Disc Disease
Nucleus pulposus (gelatinous material) degenerates and becomes fibrotic
Most commonly affects lumbar spine – subjected to greatest motion
degenerative disc disease is most commonly associated with what two things
overweight
smoking
treatment of degenerative disc disease
o Steroid injections
o Ablation
o Surgical fusion
-pain fibers from head are carried by
trigeminal (V),
acial (VII),
glossopharyngeal (IX) and
vagal (x)
“1975”
spondylolysis,
disruption of the pars interarticularis
Total spinal anesthesia can occur following attempted epidural or caudal anesthesia if there is accidental intrathecal injection. Onset is usually rapid, because the amount of anesthetic required for epidural and caudal anesthesia is
5 to 10 times that required for spinal anesthesia.
urinary retention may result of neuraxial block due to LA blocking
s2-s4 root fibers (decreases urinary tone & inhibits the voiding reflex)
- Epidural opioids also interfere with normal voiding
- Use urinary catheter
Accidental intravascular injection intervention/tx:
Lipid emulsion, 20% 1.5 mL/kg bolus OVER 1 MINUTE, should be given followed by a 0.25-mL/kg infusion.
Incremental 1 mcg/kg doses of epinephrine should be administered rather than larger 10 mcg/kg doses.
Should cardiac function not be restored additional lipid emulsion can be administered up to 10 mL/kg.
The rank order of local anesthetic potency at producing seizures and cardiac toxicity is the same as the rank order for potency at nerve blocks. how do they rank?
-LOW: Chloroprocaine has relatively low potency and also is metabolized very rapidly;
MOD: lidocaine and mepivacaine are intermediate in potency and toxicity;
!!! HIGH: levobupivacaine, ropivacaine, bupivacaine, and tetracaine are most potent and toxic.
A subdural injection of epidural doses of local anesthetic produces a clinical presentation similar to that of high spinal anesthesia, with the exception that the onset
may be delayed for 15 to 30 min and the block may be “patchy.”
diplopia is most often a symptom of what cranial nerve dysfunction? (from PDPH)
CN 6 - abuducens
volume of blood injected for an epidural blood patch:
15-20mL
differential diagnosis that should be considered as source of headache when evaluating for PDPH:
migraine,
caffeine withdrawal,
meningeal infection, and
subarachnoid hemorrhage,
abrupt discontinuation of this medication has been associated with fever, altered mental status, pronounced muscle spasticity or rigidity, rhabdomyolysis, and death
baclofen
*GABA-b agonist, is particularly effective in the treatment of muscle spasm associated with multiple sclerosis or spinal cord injury when administered by continuous intrathecal drug infusion
Excess glucocorticoid activity can produce:
HTN, hyperglycemia, increased susceptibility to infection, peptic ulcers, osteoporosis, aseptic necrosis of the femoral head, proximal myopathy, cataracts, and rarely psychosis
the preferred corticosteroid for injection procedures involving relatively vascular areas, such as the head and neck region
dexamethasone
Transient neurological symptoms (TNS) are most commonly associated with the use of what LA?
hyperbaric lidocaine (up to 12%)
Cauda equina syndrome (CES) is associated with the use of what LA?
5% Lidocaine
hyperbaric lidocaine
Cauda equina syndrome (CES) symptoms:
- bowel and bladder dysfunction
- paresis of legs (motor and/or sensory)
- diminished sensory in perineal region
- “patchy” sensory loss
- pain may be similar to nerve root compromise
TNS is most common among who? (3)
- outpatients
- males
- lithotomy position
LA associated with the worst outcomes with intravascular injection?
bupivacaine
*cardio toxic
arachnoiditis
- may be infections/noninfectious
- reaction from chemicals neurotoxicity of chg
- marked by pain
- on XR seen as “clumping of nerve roots”
meningitis and arachnoiditis result from
contamination of equipment or injected solutions
the sympathetic nervous system (SNS) appears to play a major role in some patients with
chronic pain
o A distinguishing factor of chronic pain is that what two mechanisms/factors frequently play a major role:
psychological mechanisms or environmental factors
• The first order neurons synapse with second order neurons in the
dorsal horn
• First order neurons synapse with second order neurons in the gray matter of the ipsilateral dorsal horn (communicate through interneurons) and carry on to the
thalamus
• Axons of second order neurons cross midline to the contralateral side of the spinal cord before they terminate in the spinothalamic tract and send their fibers to the thalamus, reticular formation, nucleus raphe magnus, and
periaqueductal gray
• Located in the thalamus & send fibers to somatosensory areas I & II in the postcentral gyrus of the parietal cortex & the superior wall of the sylvian fissure, respectively.
third order neurons
• Perception & discrete localization of pain take place in these cortical areas.
somatosensory cortex
o Neuroendocrine stress response is attenuated or absent in most patients with
chronic pain.
o Antidepressants are most useful for patients with
neuropathic pain.
o Antidepressants potentiate the action of
opioids
frequently help normalize sleep patterns.
Long-term side effects of neuroleptic medications include akathisia (extreme restlessness) and tardive dyskinesia (involuntary choreoathetoid movements of the tongue, lip smacking, and truncal instability).
examples of neuroleptics :
haloperidol
chlorpromazine
perphenazine
fluphenazine
o Tizanidine (Zanaflex) is a centrally acting α 2-adrenergic agonist used in the treatment of muscle spasm in conditions such as .
multiple sclerosis, low back pain, and spastic diplegia
o Cyclobenzaprine (Flexeril) also may be effective for (MS, low back pain, spastic diplegia). Its precise mechanism of action is .
unknown
