Pain Flashcards
Tourniquet pain mediated by …
C fibers
2 medications found to be useful in treating tourniquet pain?
Clonidine + ketamine
Spinal stenosis is intermittent claudication, is worse with … and relieved with …
Ambulation
Rest and siting
DDx of back pain?
No rediculopathy and axial pain -> Discogenic pain
Axial pain + rediculopathy -> Disc herniation
Lateral pain + precipitation with lateral rotation -> facet joint pain
Worst with ambulation -> spinal stenosis
Drug tolerance definition?
Exposure to a drug results in diminution of an effect or the need for higher dose to maintain an effect.
Drug dependence definition?
Drug is administered to prevent withdrawal symptoms or in which it is associated with tolerance or both.
Addiction definition?
A state of heavy physical or emotional dependence on a drug (compulsive or pathological use), this term is often synonymously used with drug dependence
Examples of neuropathic pain?
Postherptic neuralgia
Phantom limb pain
Trigeminal neurolgia
Complex regional pain syndrome
First line ttx of trigaminal neuralgia pain?
Carbamazepine (others: oxycarbamazepine which is less SE, and phenytoin)
Caused by vascular compression of trigaminal nerve root.
It’s unilateral, episodic and stabbing pain
Type of sympathetic blockade for Face and upper extremity?
Stellate ganglion block
Type of sympathetic blockade for Lowe extremity ?
Lumber symptomatic block
Type of sympathetic blockade for Upper abdomen?
Celiac plexus block
Type of sympathetic blockade for Pelvis?
Hypogastric plexus block
Indications for lumber sympathetic block?
CRPS (primarily)
Vascular insufficiency
Phantom limb pain
Stellate ganglion ?
It’s formed by fusion of inferior cervical and first thoracic ganglion and it is anterior to C7 vertebral body.
SE’s: Horner’s syndrome, hoarseness (involvement of recurrent laryngeal nerve).
Complications: pneumothorax, phernic nerve palsy, intrathecal, intravascular injection.
Myofacial pain?
Muscle pin with specific trigger points
Not neuropathic nor has dermatomal distirbution
Treatment of phantom limb pain?
Gabapentin/amitriptyline
Opioids maybe useful
TENS
Spinal cord stimulation
Intrathecal opioid pump
Stump revision if stump triggers the pain
Gabapentin acts on …
Ca channels
Phenol vs alcohol in baricity ?
Alcohol is hypobaric
Phenol is hyperbaric
Postherpetic neruralgia;
Common site
RFs
Treatment
Thoracic dermatologist followed by trigaminal distribution
> 60, sever pain or abnormalities during acute phase.
Acyclovir or corticosteroid not effective during acute phase
TCA, gaba, topical capsaicin
Allodynia definition
Painful response to a usually non-painful stimulus
Hyperalgesia definition
Increased response to a stimulus that is normally painful
Hyperpathia definition
A painful syndrome, characterized by increased rxn to stimulus , especially a repetitive stimulus, as well as an increased threshold. It may occur with hyperesthesia, hyperalgesia, or dysethesia.
CRPS 1 vs CRPS 2?
Both are sympathetic mediated however type 2 associated with nerve injury
The comments SE of morphine is
Constipation
Muscle rigidity from opiates treated with
Po Baclofen, or muscle relaxation
How long fentanyl patch works after removal?
12-16 hours
It’s prolonged action due to dermal deposits
Indication: opioid dependent chronic pain ptn
SE of major non opioids Gaba Carbamazepine Amitriptyline Tylenol
Dizziness, sedation, weight gain, peripheral edema
Dizziness, sedation, elevated liver enzymes, leuopenia, leukocytosis, thrombocytopenia, agranulocytosis, aplastic anemia.
Dry mouth, sedation, seizures
Hepatotoxic
Baclofen Toxicity
GABA b agonist, decreases excitatory neuro transmission.
Drowsiness, dizziness, GI upset.
Higher doses; seizures, delirium, tachycardia, bradycardia, hypotension.
Ttx: supportive. Charcoal or hemodialysis
Indication for spinal cord stimulation?
Failed back surgery syndrome
Refractory angina pectoris
Peripheral vascular disease
CRPS type 1
TENS machine principle?
Gate control theory of pain and conduction block theory
Gate control theory -> afferent input from large fibers decreases the transmission from small fibers (pain).
Conduction block theory -> high rate of stimulation decreases the ability of small fibers to transmit the signal.
