Exam 3 Pain

Question 1

Identify the characteristics, causes, risk factors, and treatment of cancer pain

Answer 1

Characteristics- Can be somatic, Visceral, or Neuropathic

Causes- Surgical, phantom (breast CA), chemo/radiation, compression by tumor, Bone CA.

Risks- 25% in active tx, 90% advanced dx

Tx- Opioids are mainstay 70-90%
Somatic= Opioids, NSAIDs, Neuro blocks
Visceral= sympathetic blocks
Neuropathic= Anticonvulsants, antidepressants, Opioids

Question 2

Identify the characteristics, causes, risk factors, and treatment of Diabetic pain?

Answer 2

Risk= duration of DM, Age, degree of hyperglycemia

causes=

1. microvascular- decreased blood flow leads to hypoxia, lactate build up
2. Polyol path- Less NADPH available for gluthatione reductase, Gluthatihione is a powerful antioxidant so with out it causes oxidation which leads to inflammation.
3. Glycosylation-

Tx= SSRI (duloxetine), gabapentin/pregabalin, anitdepressants, opioids, tramadol

Question 3

Identify the characteristics, causes, risk factors, and treatment of phantom pain?

Answer 3

Character- not constant about 3 day/month starts few days after surg

cause= increased C Fiber firing (Na channel activation, Abnormal firing in DH of neurons, new synaptic connection is cerebral cortex

Risk- 80% of patient with amputations

Tx- prophalactic= epidural periop, opioids, local anesthetic, clonidine

Continuous brachial plexus blockade for 7 days or oral memantine 20-30mg

Long term- opioids, gabapentin, antidepressants

non-pharm= Tens, spinal cord stim, biofeedback

Question 4

Identify the characteristics, causes, risk factors, and treatment of CRPS?

Answer 4

Character-pain/dysfunction of the SNS, hyperalgesia, allodynia

cause/risk- Previous trauma, nerve injury (causalgia), previous surgery, work-related injury, female

MOA- catecholamine activate peripheral nociceptors, after nerve injury surviving cutaneous afferents develop sensitivity, Cross-talk, change in DH such as increase afferent activity and loss of inhibitory nerves,

tx- Sympathetic blocks, gabapentin, memantine (NMDA antagonist), Ketamine infusion- 4-5 days 1-7mcg/kg/min or 4 hrs daily for 10 days at 0.35mg/kg/hr.