Pathophysiology 2 Ch 15 Mccance/heuther

Front 1

Afferent

Back 1

Ascending; sensory to spinal column

Front 2

Efferent

Back 2

Descending; innervate effector organs

Front 3

Central Nervous System (CNS)

Back 3

Brain and Spinal Cord

Front 4

Peripheral Nervous System (PNS)

Back 4

-Cranial nerves
-Spinal nerves
-Pathways (afferent/efferent)

Front 5

Where do the pain fibers enter the spinal cord?

Back 5

The dorsal horn

Front 6

Types Of Pain:
Visceral

Back 6

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. Viscera refers to the internal areas of the body that are enclosed in a cavity. Visceral pain is caused by the activation of pain receptors in the chest, abdomen or pelvic areas. Visceral pain is vague and not well localized and is usually described as pressure-like, deep squeezing, dull or diffuse. Visceral pain is caused by problems with internal organs, such as the stomach, kidney, gallbladder, urinary bladder, and intestines. These problems include distension, perforation, inflammation, and impaction or constipation, which can cause associated symptoms, such as nausea, fever, and malaise, and pain. Visceral pain is also caused by problems with abdominal muscles and the abdominal wall, such as spasm.

Front 7

Types Of Pain:
Somatic

Back 7

Somatic pain is caused by the activation of pain receptors in either the body surface or musculoskeletal tissues. A common cause of somatic pain in SCI persons is postsurgical pain from the surgical incision. It is usually described as dull or aching. Somatic pain, that is a complication of SCI, occurs with increased frequency in the shoulder, hip, and hand, although it also occurs in the lower back and buttocks. Somatic pain is probably caused by a combination of factors, such as abnormalities that may have always been there, inflammation, repetitive trauma, excessive activity, vigorous stretching, and contractions due to paralysis, spasticity, flabbiness, disuse and misuse. Generally speaking, somatic pain is usually aggravated by activity and relieved by rest.

Front 8

Types Of Pain:
Neuropathic

Back 8

Neuropathic pain is 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. Some people also complain of a stabbing, piercing, cutting, and drilling pain. This type of pain usually occurs within days, weeks, or months of the injury and tends to occur in waves of frequency and intensity. Neuropathic pain is diffuse and occurs at the level or below the level of injury, most often in the legs, back, feet, thighs, and toes, although it can also occur in the buttocks, hips, upper back, arms, fingers, abdomen, and neck.

Front 9

Fibers that carry pain info

Back 9

Alpha, Delta and C fibers - all 3 are sensory fibers, Aplha and C are both motor and sensory

Front 10

What is Methanol used for? (Tx)

Back 10

- Ethanol intoxication
- fomepizole

Front 11

Where is sensory information carried in the NS?

Back 11

to the thalamus

Front 12

Where does it get carried and interpreted?

Back 12

interpreted by the cerbral cortex

Front 13

What kinds of temperature regulation problems occur?

Back 13

-hyperthermia
-hypothermia
-malignant hypothermia

Front 14

Which temperature regulation problems are we the most susceptible to in the desert?

Back 14

-heat cramps
-heat exhaustion or stroke
(can sweat but we get dehydrated)

Front 15

Hypothermia

Back 15

-less than 35C
-vasoconstriction

Front 16

What is the major sleep center?

Back 16

hypothalamus

Front 17

Types of Sleep

Back 17

Non-REM (NREM) and REM

Front 18

NREM

Back 18

Non-REM sleep accounts for approximately 75% of total sleep time and is dominant at the beginning of sleep.

Front 19

REM

Back 19

REM sleep is when dreams occur. It accounts for approximately 25% of sleep and predominates at the end of sleep. Rapid Eye Movement is the hallmark of dream sleep.

Front 20

Normal Sleep Cycle

Back 20

there are 90 minute cycles of REM/NREM sleep through the night

Front 21

Stages of NREM sleep

Back 21

NREM Sleep
Stage 1
“Transitional” Sleep
5-10% of total sleep time

Stage 2
“Light” sleep
40-50% of total sleep time

Stages3&4
Slow Wave Sleep or Delta Sleep
25% of total sleep time

There are four distinct stages of Non-REM sleep, each discernable on an electroencephalogram (EEG). Stage 1 is transitional sleep and makes up about 5-10% of total sleep time. Humans are in Stage 2, or “light” sleep, for 40-50% of total sleep time. Stages 3 and 4 together are known as “slow wave” or “Delta” sleep because the frequency of the brain waves during these stages is very slow compared with the frequency of the brain waves during wakefulness.

Front 22

Characteristics of REM sleep

Back 22

Rapid eye movement

Paralyzed body/active brain

Muscle tone at lowest point in circadian rhythm

25% of total sleep time

Monoamine neurotransmitters, such as Norepinephrine, Histamine, and Serotonin, are blocked

In REM sleep, the brain is active and the body is atonic (lacking muscle tone), with muscle tone at it’s lowest in the circadian rhythm. There are classic rapid eye movements during this phase of sleep. Norepinephrine, histamine and serotonin are blocked in REM sleep; REM sleep is when dreams occur.

Front 23

True or False? Sleep pathophysiology is neurologically controlled by the brain; specifically, the Suprachiasmatic Nucleus of the mid-brain (where auditory and visual information is processed), and the Reticular Activating System (RAS) in the brainstem.

Back 23

True

Front 24

Common sleep disturbances

Back 24

Dyssomnias, Parasomnias and Insomnia

Front 25

Dyssomnias

Back 25

Respiratory related sleep disorders:
-Sleep Apnea (Obstructive, Central, Mixed)
-Hypopnea
-Slow Hypoventilation Syndrome (SHVS)
-Cheyne-Stokes Breathing Syndrome

Sleep-Related Movement Disorders:

-Periodic Leg Movement Syndrome

-Restless Leg Syndrome

Plain old Dyssomnia:
Narcolepsy

Front 26

Apnea

Back 26

cessation of airflow for more than 10 seconds

Front 27

Obstructive Apnea

Back 27

effort continues while airflow stops. That is, there is a blockage – an obstruction - in the airway (from the tongue, tonsils, soft palate or adenoids) that stops airflow, however, the effort to breathe continues. The obstruction is increased when the muscles are atonic during REM sleep. OSA is a common sleep disorder. It is estimated that 2% of women and 4% of men in the U.S. have OSA and that 80% may be undiagnosed.

Front 28

Central Sleep Apnea

Back 28

there is no airflow and there is no effort. That is, there is no signal to breathe. Central Sleep Apnea includes idiopathic Central Sleep Apnea Syndrome, Cheyne-Stokes Breathing Syndrome and Sleep Hypoventilation Syndrome. The American Academy of Sleep Medicine has defined Cheyne-Stokes Breathing Syndrome and Sleep Hypoventilation Syndrome (or Central Alveolar Hypoventilation) as distinct syndromes since 1999. Idiopathic CSAS, then, is extremely rare. It occurs in individuals with a normal resting arterial carbon dioxide level who may have an increased ventilatory response to CO2. During sleep, a pattern of hyperventilation occurs followed by a central apnea. These events are associated with arousals and desaturations and occur in the transition from wake to sleep.

Front 29

Sleep Hypoventilation Syndrome (SHVS)

Back 29

also known as Central Alveolar Hypoventilation or Obesity Hypoventilation. People with SHVS are hypercapnic at baseline. Carbon dioxide levels rise during sleep resulting in episodes of hypoxemia. The hypoxemic episodes are not directly caused by apnea or hypopnea, although central apnea may also be noted. The episodes worsen in REM sleep. This syndrome is most commonly seen in conjunction with obesity, neuromuscular disorders or Chronic Obstructive Pulmonary Disease (COPD).

Front 30

Cheyne-Stokes Breathing Syndrome (CSBS)

Back 30

a pattern of cyclic waxing and waning of respirations. Rapid, high volume respirations lead to apnea. This pattern repeats itself and is typically absent in REM sleep. CSBS is present in many neurological conditions and in congestive heart failure. CSBS may accelerate the progression of Congestive Heart Failure (CHF) and the presence of CSBS in CHF may increase mortality.

Front 31

Mixed apnea

Back 31

defined as a period of apnea that starts as a central event and ends as an obstructive event when the muscles in the airway relax. That is, effort resumes before airflow. This term is somewhat controversial, since a mixed apnea would likely be treated as an obstructive apnea; for now, most sleep laboratories continue to classify mixed apnea.

Front 32

Hypopnea

Back 32

the reduction of airflow in conjunction with an oxygen desaturation of at least 4% or an EEG arousal lasting at least three (3) seconds. Sleep laboratories differ in the amount of airflow reduction required to classify an event as a hypopnea. However, if a hypopnea causes a decrease in oxygen saturation or an arousal from sleep, it can be considered significant regardless of the amount of airflow reduction.

Front 33

Periodic Leg Movement Syndrome

Back 33

refers to a burst of electromyogram (EMG) activity in the anterior tibialis muscle of the legs. A diagnosis of PLMS requires four or more movements per hour with each movement lasting 0.5-5 seconds and with an interval of 4-90 seconds between movements. Additionally, there should be an arousal on the EEG of more than three seconds
within two seconds of the leg movement.

Front 34

Restless Leg Syndrome

Back 34

has a strong association with PLMS; yet the two are separate disorders. The urge to move the legs (known as akathisia) prevents initiation of sleep. Causes of RLS include low iron levels, peripheral neuropathy, some pharmacologic agents, caffeine and family history of RLS.

Front 35

Narcolepsy

Back 35

Narcolepsy is a chronic neurological disorder characterized by excessive daytime sleepiness despite restful sleep at night and daytime “sleep attacks.” The sleep attacks may be accompanied by hallucinations and paralysis. Polysomnography shows a rapid onset of REM sleep. Recent research (Mignot et al. Nature Genetics 41, 708-711(2009)) indicates that narcolepsy is an autoimmune disease.

Symptoms: The symptoms of narcolepsy are debilitating. Excessive Daytime Sleepiness is present despite a restful sleep at night. Cataplexy, which is the loss of muscle tone, occurs especially in response to strong emotion; people with narcolepsy may fall asleep immediately after laughing or crying. Sleep hallucinations, especially at transition from wake to sleep (hypnagogic), are reported frequently. Sleep paralysis, sometimes accompanied by hallucinations, is often present and is extremely frightening to the patient, since he or she awakens and is unable to move. Automatic behavior may occur: a person attempts to complete a task with no conscious awareness of doing so. Additionally, nocturnal sleep may be disrupted.

Front 36

Parasomnias

Back 36

associated with arousals and sleep stage transitions. Some may be associated with primary sleep disorders: for example, sleep enuresis and confusional arousals are often seen in patients with OSAS.
The parasomnias include confusional arousals, sleep walking, night terrors, REM behavior disorder, recurrent isolated sleep paralysis, sleep- related dissociative disorder, sleep enuresis (bedwetting), exploding head syndrome, sleep-related hallucinations and sleep-related eating disorders.

Front 37

Insomnia

Back 37

the most widely reported symptom of a sleep disorder. It is only rarely a primary disorder; it is usually a symptom of another sleep disorder. Insomnia may occur at sleep onset, during the course of sleep or prior to the desired awakening
time.

 Short term insomnia, or transitional insomnia,
lasts less than one month.

 Chronic insomnia lasts one month or longer
and is accompanied by daytime impairment.

Front 38

Blepharitis

Back 38

Inflammation of the eyelids

Front 39

Hordeolum

Back 39

(stye) infection of sebaceous glands of the eyelids

Front 40

Chalazion

Back 40

Infection of the meiobomian (oil secreting gland)

Front 41

Conjunctivitis

Back 41

Inflammation of the conjunctiva

Acute bacterial conjunctivitis (pinkeye)

Highly contagious

Mucopurulent drainage from one or both eyes

Viral conjunctivitis

Allergic conjunctivitis

Trachoma (chlamydial conjunctivitis) - responsible for a large portion of the world's blindness

Front 42

Vision Changes and Aging

Back 42

Cornea
Anterior chamber
Lens
Ciliary muscles
Retina

Front 43

Alterations in Ocular Movement

Back 43

Strabismus (a disorder in which the eyes do not line up in the same
direction when focusing. The condition is more commonly known
as "crossed eyes.")

Nystagmus
(a form of involuntary eye movement. It is characterized by alternating smooth pursuit in one direction and saccadic movement in the other direction.)

Front 44

Alterations in Visual Acuity

Back 44

Amblyopia
Scotoma
Cataracts
Retinal Detachment

Front 45

Amblyopia

Back 45

lazy eye," is the loss of one eye's ability to see
details. It is the most common cause of vision problems in children.

Front 46

Scotoma

Back 46

Portion(s) of the retinal field that are non-functional (i.e., blind areas). Scotomas may be central, if caused by macular or optic nerve disease, or peripheral if the result of chorioretinal lesions or retinal holes

Front 47

Cataracts

Back 47

A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light.

A senile cataract, occurring in the elderly, is characterized by an initial opacity in the lens, subsequent swelling of the lens and final shrinkage with complete loss of transparency.[2] Moreover, with time the cataract cortex liquefies to form a milky white fluid in a Morgagnian cataract, which can cause severe inflammation if the lens capsule ruptures and leaks. Untreated, the cataract can cause phacomorphic glaucoma. Very advanced cataracts with weak zonules are liable to dislocation anteriorly or posteriorly. Such spontaneous posterior dislocations (akin to the historical surgical procedure of couching) in ancient times were regarded as a blessing from the heavens, because some perception of light was restored in the cataractous patients.

Front 48

Retinal Detachment

Back 48

a separation of the light-sensitive membrane in the back of the eye (the retina) from its supporting layers.

Symptoms:
Bright flashes of light, especially in peripheral vision
Blurred vision
Floaters in the eye
Shadow or blindness in a part of the visual field of one eye

Front 49

Papilledema

Back 49

optic disc swelling that is caused by increased intracranial pressure. The swelling is usually bilateral but can be unilateral which is extremely rare and can occur over a period of hours to weeks.

Front 50

Dark Adaptation

Back 50

the ability of the eye to adjust to various levels of darkness and light

Front 51

Alterations in Accomodation

Back 51

Accommodation is the process whereby the thickness of the lens changes
Oculomotor nerve changes
Decreased flexibility of the lens
Manifestations:
Diplopia, blurred vision, and headache

Front 52

Alterations in Refraction

Back 52

Myopia (nearsighted)
Hyperopia (farsighted)
Astigmatism
May coexist with myopia or hyperopia

Front 53

Neurologic disorders

Back 53

Hemianopia
(loss of vision in either the whole left or the whole right half of the field of vision)

Injury to the optic chiasm

Homonymous hemianopsia

Front 54

Aging and Hearing

Back 54

Cochlear hair cell degeneration
Loss of auditory neurons in spiral ganglia of organ of Corti
Degeneration of basilar conductive membrane of the cochlea
Decreased vascularity of cochlea
Loss of cortical auditory neurons

Front 55

Ear Infections

Back 55

Otitis externa
Infection of the outer ear
Commonly caused by prolonged moisture exposure (swimmer’s ear)
Otitis media
Acute otitis media
Otitis media with effusion

Front 56

Auditory Dysfunction

Back 56

Conductive hearing loss
Impaired sound conduction
Sensorineural hearing loss
Impairment of the organ of Corti or its central connections
Presbycusis (age-related hearing loss)
Mixed hearing loss
Functional hearing loss

Front 57

Hyposmia

Back 57

a reduced ability to smell and to detect odors

Front 58

Anosmia

Back 58

inability to detect any odors

Front 59

Olfactory hallucinations

Back 59

(phantosmia), you detect smells that aren't really present in your environment

Front 60

Parosmia

Back 60

also known as troposmia, is an olfactory dysfunction that is characterized by the inability of the brain to properly identify an odor’s “natural” smell. What happens instead is that the natural odor is transcribed into what is most often described as an unpleasant aroma, typically a “‘burned,’ ‘rotting,’ ‘fecal,’ or ‘chemical’ smell.” There are instances, however, of pleasant odors. This is more specifically called euosmia.

Front 61

Hypogeusia

Back 61

A reduced ability to taste things (to taste sweet, sour, bitter, or salty substances).

Front 62

Ageusia

Back 62

Complete inability to taste

Front 63

Parageusia

Back 63

a bad taste in the mouth.
One common form of parageusia is a metallic taste of food. This can be a side effect of several medications, such as acetazolamide, eszopiclone, zopiclone, metronidazole, or etoposide.

Front 64

Somatosensory Function

Back 64

Touch
Sensation involves modality, intensity, location, and duration
Receptors are present in the skin

Proprioception
Depends on inner ear, vision, and receptors in joints and ligaments

Front 65

Vestibular nystagmus

Back 65

involuntary movement of the eyes. Most frequently it is composed of a mixture of slow and fast movements of the eyes. Nystagmus can occur normally, such as when tracking a visual pattern. Nystagmus may also be abnormal, usually in situations where one would want the eyes to be still, but they are in motion. Vertigo (a sensation of spinning), is often accompanied by nystagmus.

Front 66

Vertigo

Back 66

a type of dizziness, where there is a feeling of motion when one is stationary.[2] The symptoms are due to a dysfunction of the vestibular system in the inner ear.[2] It is often associated with nausea and vomiting as well as difficulties standing or walking.

Front 67

Ménière disease

Back 67

a disorder of the inner ear that can affect hearing and balance to a varying degree. It is characterized by episodes of vertigo and tinnitus and progressive hearing loss, usually in one ear. It is caused by lymphatic channel dilation, affecting the drainage of endolymph.