Pain Flashcards
What is hyperalgesia?
Increased pain from a stimulus that normally evokes pain
What is allodynia?
Pain due to stimulus that does not normally evoke pain
What is Parasthesia ?
Abnormal sensation which can be spontaneous or evoked
What is dysaesthesia?
An unpleasant abnormal sensation evoked or spontaneous
What is neuralgia?
Severe pain in the distribution of sensory nerves
Chronic pain?
Pain that persists beyond normal tissue healing for more than 3 months
It is real, subjective, influenced by past experiences
Neuropathic pain?
Pain that arises from a lesion of the somatosensory system
Patients with chronic pain disorder present with which features?
Somatization and catastrophizing
Somatization: physical symptoms as a manifestation of psychological stress)
Symptoms are medically unexplained
Catastrophizing: unbearable, horrible
What is Trigeminal neuralgia? And what is the pathology behind it?
Sudden, Unilateral, brief stabbing pains in the distribution of one or the V branches
Always involved peripheral trigeminal afferant neurone. Likely that patients have lesion pressing on where the nerve exists brain stem eg via superior cerebellar eatery which causes demyelination and hypermyelination
What are the causes of pain in the head and neck region?
oral facial (tmj, sinus, salivary glands) vacular neurological psychogenic
What is the incidence of TN? Who is more common amongst?
2-5/100 000
More common in females than males
What is the peak age of onset for people with TN? What is this pain quality like in TN?
50-60
Sharp agonising electric shock felt superficially in skin or buccal mucosa which can be triggered by light, mechanical touch at the trigger zone which usually lasts a few seconds but occasionally 1-2 mins
Pain may occur at intervals followed by an interval free period
What are the two broad categories for management of TN?
Medical and surgical
What medications are implicated in TN?
Carbamazepine 100mg Gabapentin Phenytoin Lamotrigene Valproate Topirimate
Which medication can be used as a diagnostic aid for TN?
Carbamezapine
When taking carbamezapjne for TN what investigations are needed?
Blood pressure
FBC
Liver function
Plasma levels
What are the side effects to carbamezapjne?
High blood pressure, Ataxia Drowsiness Leukopania Liver toxicity
How can you treat TN surgically ?
Local surgical treatment or central surgical treatment
Which local treatment methods for TN exist?
LA + bupivicane
LA + Glycerol block
Cryotherapy Peripheral neurectomy (alcohol phenol)
What are the disadvantages to local surgical treatment for TN?
Temporary sensory loss
How do you treat V neuralgia using central surgery?
Micro vascular decompression
Partial sensory rhizotomy
Radio frequency lesion or thermocoagulation
Retro gasserian glycerol injection
What is micro vascular decompression?
Separation sup cerebellar artery from Trigeminal nerve
No sensory loss
What is partial sensory rhizotomy?
Section sensory fibres off Trigeminal nerve
Leads to sensory loss
Radio frequency lesion or thermocoagulation involves what?
This is when the heat is applied to the sensory lesion behind ganglion
This leads to sensory loss, corneal anaesthesia and dysaesthesia
How do you perform a retro-gasserian glycerol block?
Glycerol is infected into the meckels cave
This doesn’t cause sensory loss and recurrs after 1 year
What is Glossopharyngeal neuralgia?
Sharp pain along distribution of CN9
Pain felt in the throat, Tonsillar fossa and adjacent fauces
What provokes the pain sensation felt in Glossopharyngeal neuralgia?
Can be spontaneous or evoked by mechanical stimulation of Tonsillar area eg coughing of swallowing
Where does the pain in Glossopharyngeal neuralgia radiate to?
External ear, angle of jaw and neck
How is the pain in Glossopharyngeal neuralgia relieved?
LA to trigger zone
What is the incidence of Glossopharyngeal neuralgia?
1/200 000
What is post herpetic neuralgia?
Chronic pain with skin changes in the distribution of a nerve following herpes zoster
What type of pain is characteristic of post her petic neuralgia?
Burning, dysaesthesia, Parasthesia, cutaneous pain
Usually moderate intensity but since content and intractable can be intolerable
Which nerve if usually involved in PHN?
Va
What mood disorder is associated with PHN?
Depression
T/F the area skin affected by herpes zoster shows no changes?
F
On occasion there may be cutaneous scarring and lack of pigmentation in that area
What is the prevention and treatment for PHN?
High dose Acyclovir during initial herpes zoster infection to prevent
Treatment Amitryptulin Pregabalin Topic LA Capsaicin patches
What are tension headaches?
Dull aching head pain usually symmetrical in nature
Nausea occasional vomiting
Exacerbations with pounding headaches, but less intense than migraine
Where do tension headaches usually arise?
Frontal/orbital occipital whole scalp
Diffuse and band like usually bilateral and sometimes more on one side
Who is more commonly affected by tension headaches? Males or females?
Females 4:1
What age do tension headaches begin
Usually before 30 as young as 8
What are the precipitates to tension headaches ?
Emotional stress
Depression anxiety
Exercise
Alcohol (sometimes can relive it)
How so you manage tension headaches?
Relaxation techniques
Analgesics
Anxiolytics although should be avoided since some patients becomes depressed and others become dependant
TCA: amitrtiptyline