Neurologic System Flashcards
What are the (3) types of pain?
Somatic
Visceral
Neuropathic
Somatic Pain
caused by the activation of pain receptors in either the body surface or musculoskeletal tissues
*common cause of somatic pain in SCI persons is postsurgical pain from the surgical incision
Visceral Pain
is the pain we feel when our internal organs are damaged or injured and is by far the most common form of pain
Neuropathic Pain
caused by injury or malfunction to the spinal cord and peripheral nerves. Neuropathic pain is typically a burning, tingling, shooting, stinging, or “pins and needles” sensation
What are nociceptors?
Where are they located in each of the 3 areas of pain?
The nociceptors (free nerve endings) are distributed in the:
somatic structures (skin, muscles, connective tissue, bones, joints);
visceral structures (visceral organs such as liver, gastro-intestinal tract).
Nociceptors transmit impulses to the brain via C fibers and A-delta fibers.
What s the Pain pathway?
Transmission
Perception
Modulation
Pain Transmission
- Noxious stimulus occurs
- impulse travels via A-delta or C fibers to the dorsal horn of the spinal cord.
- Impulse ascends to the thalamus, brain stem, and cerebral cortex for processing and interpretation.
Pain Perception
Interpretation influenced by cultural preferences, male/female, life experience both past and present; location, character, location, and intensity
learned behaviors regarding pain.
Pain Modulation
Mechanisms that increase or decrease transmission of pain signals within the system (either before, during, or after the pain is perceived).
Endogenous opioids such as endorphins can block the transmission of pain impulses to decrease the perception of pain.
Endorphin receptors are located close to known pain receptors in the periphery and ascending and descending pain pathways.
What are the (2) main classifications of pain?
Acute & Chronic
What is the normal range of body temperatures?
- 2 - 37.7 C
96. 2 - 99.4 F
When should a fever be treated?
When it causes serious side effects, such as cardiovascular stress, nerve damage, brain damage, or convulsions
Heat cramps
severe, spasmodic cramps in the abdomen and extremities; follow prolonged sweating (due to loss of sodium); signs include fever, rapid pulse rate, and increased blood pressure
Heat exhaustion
- due to prolonged high core or environmental temperatures
- profound vasodilation and profuse sweating
- dehydration, decreased plasma volume, hypotension, decreased cardiac output, and tachycardia; symptoms include weakness, dizziness, confusion, nausea, and fainting
Heat Stroke
when the core temperature rises high, the regulatory center stops working and the body’s mechanisms for heat loss fail;
symptoms = high core temperature, ABSENCE of sweating, rapid pulse, confusion, agitation, and coma.
Complications = cerebral edema, degeneration of the CNS, renal tubular necrosis, and liver failure…delirium, coma, and eventual death is not corrected.
can be lethal
Malignant hyperthermia
rare muscle disorder that can become a complication of surgery. It is triggered by inhaled anesthetics and depolarizing muscle relaxants
Can be fatal
- Calcium function in the muscle cells becomes altered causing hypermetabolism, muscle contraction
- increases the work of the muscleincreasing oxygen consumption and increases lactic acid production
- acidosis develops, body temperature rises rapidly. The patient becomes tachycardic with dysrhythmias, hypotensive, decreased cardiac output, and eventually will progress to cardiac arrest.
Signs resemble those of coma= unconsciousness, absent reflexes, fixed pupils, apnea.
What are the (4) mechanism of heat loss?
Radiation
Conduction
Convection
Evaporation
Radiation
heat loss through waves emanating from surfaces with temperature higher than the surrounding air
Conduction
heat loss though direct touch from one surface to another, so that warmer surface loses heat to cooler surface
Convection
heat loss through currents of gases or liquids; exchanges warmer air at body’s surface with cooler air in surrounding space
Evaporation
Body water evaporates from surface of skin and from mucous membranes; sweating promotes heat loss
Body’s response mechanisms to hypothermia:
“S.H.I.P”
- Stupor; heart rate and respiratory rates decline, cardiac output diminishes; metabolic rate falls; acidosis; eventual cardiac dysrhythmias and asystole
- Hypothalamus induces shivering
- Intermittent reperfusion of extremities (aka, Lewis phenomenon)
- Peripheral vasoconstriction
Describe the Sleep Cycle
Stage 1: drowsiness
Stage 2: period of light sleep (heart rate slows, brain does less complicated tasks)
Stages 3 & 4: deep sleep known as slow-wave or delta sleep (body makes repairs; body temperature and BP decrease)
Stage 5: rapid eye movement or REM characterized by intense dreams (increase in-eye movement, heart rate, breathing, BP and temperature)
Sleep Deprivation
can cause CNS symptoms, impair the immune system and put the person at risk for disease (including diabetes type 2 and heart disease),
decrease reactions times, cause chronic pain, growth suppression, risk for obesity, and decreased body temperature.
Glaucoma
intraocular pressure (>12-20 mmHg)
loss of acuity from pressure on the optic nerve causing optic nerve fibers to die
Glaucoma: Open Angle
obstruction of the outflow tract causing a build up of aqueous humor
a leading cause of blindness; few symptoms to alert the patient
Glaucoma: Angle Closure
displacement of the iris toward the cornea causing an obstruction of aqueous humor outflow
causes sudden rise in intraocular pressure, pain, and visual disturbance
Glaucoma: Congenital Closure
rare disease associated with congenital malformation and other genetic anomalies
What is ARMD?
Age Related Macular Degeneration
A - Age
R - Retinal Vein Occlusion
M - Myopia (nearsightedness)
D - Diabetes mellitus
Compare WET vs. DRY ARMD
Dry=nonexudative; slow progressive with drusen (waste products) in the retina
-limits night vision and causes difficulty reading
Wet=exudative; accumulation of drusen, abnormal blood vessels, leaking of blood or serum, retinal detachment, scarring, loss of photorecptors, and severe loss of central vision
The retina detaches from where it SITS. What does this acronym stand for?
S - Secondary to some intra-ocular problem such as with glaucoma or with a tumor
I - Idiopathic
T - Traumatic
S - Surgery for cataract
Symptoms of Retinal Detachment
Remember 3F’s
Falling acuity
Floaters
Flashes (migraine)
General definition of Conjunctivitis
an inflammation of the conjunctiva caused by bacteria, viruses, allergies, or chemical irritants.
Viral conjunctivitis
Watery, itchy eyes; sensitivity to light.
One or both eyes can be affected
Highly contagious; can be spread by coughing and sneezing
Bacterial conjunctivitis
A sticky, yellow or greenish-yellow eye discharge in the corner of the eye.
In some cases, this discharge can be severe enough to cause the eyelids to be stuck together when the person wakes up.
One or both eyes can be affected.
Contagious (usually by direct contact with infected hands or items that have touched the eye)
Allergic conjunctivitis
Watery, burning, itchy eyes; often accompanied by stuffiness and a runny nose, and light sensitivity Both eyes are affected. Not contagious
Trachoma
(Chlamydial conjunctivitis) results from the sexually transmitted infection Chlamydia trachomatis
often associated with poor hygiene or an infant born vaginally to an affected mother
Strabismus
one eye deviates from the other when the person is looking at an object.
caused by weak or hypertonic muscle in one eye.
deviation may be upward, downward, inward, or outward.
In children strabismus requires rapid intervention to preserve vision in the affected eye
Nystagmus
an involuntary unilateral or bilateral rhythmic movement of the eyes
It may be present at rest or when the eye moves
may be regular or jerky movement
may be caused by an imbalanced reflex activity of the inner ear or can be cause by irregularities of some of the cranial nerves
Amblyopia
reduced vision in an eye caused by cerebral blockage of the visual stimuli
Scomata
a defect of the central field of vision
Cataracts
cloudy or opaque areas in the ocular lens
The incidence increases with age
most commonly it is a result of degeneration
Papilledema
edema and inflammation of the optic nerve where it enters the eyeball
caused by obstruction of venous return from the retina due to either increased intracranial pressure, retrobulbar neuritis, or changes in retinal blood vessels
Presbyopia
(happens with advancing age)
the loss of accommodation in which the ocular lens becomes larger, firmer, and less elastic.
reduced near vision, causing the individual to hold reading materials at arm’s length