PAIN Flashcards
supraspinal modulation occurs in which two places
periaqueductal gray matter (PAG) and rostral ventromedial medulla pathway (RVM)
discuss MOA of opioids
bind to mu, kappa, and delta; they presynaptically lower theinflux of calcium to reduce the neurotransmitter release in sensory C fibers and postsynaptically increase the transport of potassium in the cell to facilitatehyperpolarization in second order neurons.
What is a pKA
pH at which 50% of the drug is ionized. The nonionized form crosses lipid membranes easily. The lower the pKA, the faster the onset.
stimulation of spinal cord stimulators increase in what 4 instances?
increase in amplitude, frequency, pulse width, and supine position
in spinal cord stimulation, nerve root stimulation increases in _____ stimulation and axial stimulation increases in ______ stimulation
longitudinal
transverse
electrode of spinal cord stimulator should be placed where?
2 spine segments below target level so that at least 3 inches of the lead body lies within the epidural space to maximize electrode stability.
Cervical placement: below T1/2
Lower part of body: T12-L1
Upper extremity: T2-3 or T3-4
Block most appropriate for visceral pelvic pain to bladder, urethra, and external genitalia
sacral nerve block
block most appropriate for chronic pelvic pain from gynecologic, colorectal, or genitourinary cancer
superior hypogastric plexus block
Where is the hypogastric plexus located
at the lower 1/3 of the L5 vertebral body in the anterolateral border of L5 bilaterally
Post chemo pain: Name the effects of the following drugs:
- anthracyclines
- alkylating agents
- paclitaxel syndrome
- taxanes
- mucositis or painful mouth sores
- same
- arthralgias/myalgias which range from mild to debilitating
- painful peripheral neuropathy.
three main causes of pain wiht lung cancer:
- skeletal metastatic disease
- pancoast tumor
- chest wall disease
treatment option for costopleural syndrome in mesothelioma
percutaneous cervical cordotomy ; interrupts the spinothalamic tract at C1/2 causing a contralateral loss of pain perception below the level of the lesion
Describe the WHO analgesic ladder for cancer pain relief
- mild to moderate pain: non-opioid analgesics +/- adjuvant
- moderate: short acting opioids +/- non-opioid analgesics +/- adjuvant
- moderate to severe pain: short and long-acting opioids +/- non-opioid analgesics +/- adjuvant
What is the IASP diagnostic criteria for CRPS?
- presence of initiating noxious event or cause of immobilization
- continuing pain, allodynia, or hyperalgesia in which the pain is disproportionate to any known inciting event
- evidence at some time of edema, changes in skin blood flow, or abnormal sudomotor activity in the region of pain (can be sign/symptom)
- this diagnosis is excluded by the existence of other conditions that would otherwise account for the degree of pain and dysfunction.
Name the things innervated by the 3 branches of the dorsal ramus of the nerve root
Lateral br: paraspinal muscles, skin, SI joint
Intermediate branch: innervates longissimus muscle
Medial branch, facet joint, multifidus muscle, interspinala ligament, muscle, periosteum of the neural arch.
name the innervation of facet joints in cervical, thoracic, and lumbar spin
cervical/thoracic, innervated by medial branches of corresponding dorsal rami (C5/6 joint innervated by C5 and C6)
*** except C2/3 which is innervated soley by C3 as the dorsal ramus divides into two medial branches, the larger of which is known as the 3rd occipital nerve.
Lumbar: one above and same level (L4/5 innervated by L3 and L4)
annulus fibrosis (AF) is composed of ____ collagen, nucleus pulposus (NP) is composed of _______ in _____ collagen network
Type I;
water and proteoglycans in Type II collagen network
Name the dallas discogram description scale of internal disc disruption
0 - no annular disruption
1 - NP leaking into inner annulus
2 NP leaking into outer annulus
3 - NP leaking beyond the outer annulus
Modic changes: I-III
I - trabeculae are fractured, shorter and broader; marrow is substituted by serum; brith on T2, dark on T1 (edema)
II - trabeculae are also fracture in many places but are shorter and broader. marrow is substituted by fat; bright on T2, and look like fat on T1
III - rare - bone scar tissue; dark on T2 and T1 (bony sclerosis)
recommended max doses of anesthetics
Bupivacaine: 2.5mg/kg; no > 175mg
lidocaine: 4.5mg/kg, no > 300mg
Ropivacaine: 5mg/kg, no > 200mg
Procaine: 7mg/ky, no > 350-600mg
How do corticosteroids act in injections
direct inhibition of C-fiber neuronal membrane excitation and induce synthesis of phopholipase A2 inhibitor, thereby preventing release of substrate for prostaglandin synthesis. - may benefit the many patients with chemical radicular pain syndrome.
