Pathophysiology- Exam II Chapters 13-24

common causes of autonomic dysreflexia

spinal injury occurring at T6 or higher

occurring at T6 or lower: restrictive clothing, full bladder/UTI, pressure areas, fecal impaction

Autonomic Dysreflexia

involves uncontrolled activation of autonomic neurons

symptoms of autonomic dysreflexia

increased blood pressure (vasoconstriction/hypertension), lowered heart rate (vasodilation/bradycardia)

reticular formation

part of the brain responsible for consciousness

classifications of brain contusions

coup and contrecoup

epidural bleed

caused by an arterial bleed, between dura and skull

hemorrhagic stroke

stroke due to burst or torn vessels

reversible causes of stroke

hypertension, smoking, hyperlipidemia

What type of hemorrhage is caused by an AV malformation

intracerebral hemorrhage

Symptoms of meningitis

Fever, headache, stiff neck, leukocytosis, nausea, vomiting

encephalitis

infection of the parenchyma of the brain

Encephalitis infection can cause

can cause necrotizing hemorrhage and cerebral edema

Common causes of seizures

CNS infection, autoimmune disorders, genetics, structural causes (such as injury)

Manifestations of seizure

motor, sensory, autonomic, and psychic phenomenon

convulsion (seizure)

an involuntary contraction or series of contractions of the voluntary muscles; sudden disturbances in mental functions and body movements, some with loss of consciousness

tonic-clonic seizure

Includes loss of consciousness, muscle rhythmic contraction and relaxation of muscles in extremeties; incontinence of urine

absence seizure

characterized by staring while appearing awake but unable to interact

Characteristics of Alzheimer's dementia

Short term memory loss, difficulty with language, changes in behavior

Neurodegenerative changes of Alzheimer's dementia

Atrophy with loss of neurons; neurofibrillary tangles; and beta amyloid plaque

functions of plasma

carry cells that transport gases; aid in body defenses; prevent blood loss

albumin

54% of plasma proteins; contributes to plasma osmotic pressure

globulins

38% of plasma proteins; constitute the antibodies of the immune system

Monocytes/Macrophages

important role in chronic inflammation

erythrocyte sedimentation rate (ESR)

is a test that indirectly measures the degree of inflammation in the body

Stages of hemostasis (clotting)

1.vessel spasm (vasoconstriction)

2. platelet plug formation

3. blood coagulation

4. clot retraction

5. clot dissolution

vessel spasm

initiated by exposed collagen- slows blood flow to minimize blood loss. Neural reflexes, thromboxane, and serotonin contribute to this process

platelet plug formation

vWf binds to platelet receptors causing platelets to adhere to the exposed collagen

ADP and TXA2 released by these platelets, which attract additional platelets leading to the formation of a plug

blood coagulation (clotting)

collagen and tissue factor serve as activators for extrinsic and intrinsic pathways, which converge with activation of factor X, converting prothrombin to thrombin, which converts fibrinogen to the insoluble fibrin threads.

Clot retraction

Fibrin strands are pulled toward the platelets, squeezing serum from the clot to join the edges of the broken blood vessel

Clot dissolution

Inactive plasminogen is converted to active plasmin by tissue plasminogen activator. Plasmin then breaks apart the fibrin links holding platelets together causing the clot to slowly dissolve

two forms of hypercoagulability states

conditions that create increased platelet function and conditions that cause accelerated activity of the coagulation system

Bleeding can occur as a result of

as a result of disorders associated with platelet number or function, coagulation factors, or blood vessel integrity.

conditions that attribute to hypercoagulability with potential of thrombi formation

smoking

elevate lipid & cholesterol

diabetes from hyperglycemia

pregnancy/postpartum

oral contraceptives

immobility

arterial thrombi

due to turbulent blood flow and platelet adherence

venous thrombi

due to stasis of blood flow with increased coagulation factors

disseminated intravascular coagulation

widespread coagulation depletes clotting factors resulting in uncontrolled bleeding

petechiae

seen almost exclusively in conditions with platelet deficiency

Erythropoietin

A hormone produced and released by the kidney that stimulates the production of red blood cells by the bone marrow

primary polycythemia

caused by genetic mutation

secondary polycythemia

erythropoietin levels increased due to hypoxic conditions

Reticulocyte

immature red blood cell

Measuring rate of red blood cell production in the bone marrow

based on the percentage of reticulocytes

aplastic anemia

hematopoiesis is suppressed directly or through immune mechanisms

Thalassemia

inherited disorders of hemoglobin synthesis, decrease of either the a- or b- globin chains of HbA

Sickle cell disease

inherited disorder; abnormal Hgb leads to chronic hemolytic anemia, pain, and organ failure

Megaloblastic anemia

excess cytoplasmic growth and structural proteins impaired DNA results in large red cells

Vitamin B12 deficiency anemia

along with folic acid deficiency, a type of megaloblastic anemia

chronic kidney disease

anemia due to reduced production and release of erythropoietin to stimulate bone marrow

signs and symptoms of a transfusion reaction

hives/rash, chills, fever, tachycardia, headache, flushed face, dyspnea, hypotension, anxiety

granulocytes and the agranular monocytes/macrophages are derived from the __________ stem cell and circulate in the blood

myeloid

T and B lymphocytes originate from

lymphoid cells in the bone marrow

neutropenia

the most common type of leukopenia

s/s of neutropenia

fever, chills, extreme weakness, decreased WBC count

Hodgkin lymphoma

characterized by reed-sternberg cells, starts as a malignancy in a single lymph node and then spreads to nearby lymph nodes

Non-Hodgkin lymphoma

A group of lymphocytic cancers that spread to various tissues throughout the body WITHOUT reed-sternberg cells

Acute lymphocytic leukemia (ALL)

A group of neoplasms composed of precursor B or T lymphocytes known as lymphoblasts

Chronic lymphocytic leukemia (CLL)

a clonal malignancy of B lymphocytes, the most common form of leukemia in adults in the western world

Acute myelocytic leukemia (AML)

Neoplasms affecting the myeloid precursor cells in the bone marrow known as myeloblasts

Chronic myelocytic leukemia (CML)

disorder of the pluripotent hematopoietic progenitor cell, requires 'philadelphia chromosome', progresses through 3 clinical phases

Multiple myeloma

proliferation of malignant plasma cells in the bone marrow and osteolytic bone lesions throughout the skeletal system

s/s of acute leukemia

weight loss, bone pain, fever, fatigue, bruising, increased blast cells, decreased RBCs, thrombocytopenia

upper motor neurons

project from the motor cortex to the brain stem and spinal cord and control the lower motor neurons

lower motor neurons

ventral horn motor neurons, innervate skeletal muscles

afferent neurons

carry impulses to the CNS from muscles

efferent neurons

take information from the CNS to the rest of the body

Damage to upper motor neurons causes

spastic paralysis

damage to lower motor neurons causes

flaccid paralysis

pyramidal motor system (direct)

voluntary muscle movement/ delicate muscle movement

extrapyramidal system (indirect)

involuntary movements/ crude movement

Acetylcholine

triggers muscle contraction by releasing and binding across the membrane end plate

why don't spinal reflexes require a functioning brain?

sensory neurons from the muscle send information up to the brain via the spinal cord, which the process does not involve the brain.

myasthenia gravis

Antibodies bind to acetylcholine receptors causing fewer to be available for signal transmission

symptoms of myasthenia gravis

ptosis, diplopia, food regurgitation, limited facial expression, muscle wasting, difficulty chewing o

mononeuropathy (like carpal tunnel syndrome)

trauma or compression of a single spinal nerve that interferes with nerve transmission

Symptoms of mononeuropathy (like carpal tunnel syndrome)

muscle weakness, atrophy, sensory changes, dysesthesias in one peripheral nerve

polyneuropathy- guillain-barre syndrome

damage to multiple peripheral nerves leading to the most distal nerve transmission symptoms initially

symptoms of polyneuropathy- guillain-barre syndrome

rare complication to the flu vaccine- progressive muscle weakness 'toes to nose', flaccid paralysis, paresthesia, weakness, ataxia

Parkinson's disease

Basal ganglia disease caused by decreased dopamine in motor transmission leading to impaired extrapyramidal motor function.

Symptoms of Parkinson's Disease

bradykinesia, shuffling gait, rigidity, face masking, tremors, slow reaction time, frequent falls

amyotrophic lateral sclerosis (ALS)

Damage to the upper and lower motor neuron function leading to complete muscle paralysis throughout the body.

symptoms of ALS

muscle twitch, cramp, spasticity, muscle weakness, slurred or nasal speech, difficulty chewing or swallowing

Multiple Sclerosis (MS)

an immune-mediated disease that causes demyelination of the nerve axons and plaque formation that interferes with normal motor nerve transmission

Autonomic Dysreflexia- the upper body ________________, causing _______, ___________, and _____________ .

Vasodilates, causing headache, flushed face, and sweating

Autonomic Dysreflexia- lower body ______________, ___________, and ___________ .

vasoconstricts, causing cool, pale skin, and no sweating.

spinal cord injury can cause loss of what functions of the body

sensory and motor function below injury, bladder/ bowel control, sexual function

energy requirements of the brain

oxygen and glucose

afferent neuron

conducts impulses toward the CNS from the body periphery

efferent neuron

conducts impulses away from the CNS to muscles and glands

What body response can you see in acetylcholine (ACh) release

lowering of BP, smooth muscle contraction, lowers or regulates heart rate

Is ACh sympathetic or parasympathetic?

parasympathetic

What body response can you see in norepinephrine release?

vasoconstriction, increased heart rate, sweating

What body response do you see in epinephrine relase

bronchodilation, vasoconstriction, pupil constriction, increased alertness

Four Major Modalities of Sensory Experience

Discriminative touch

Temperature sensation

Body position

Nociperception (pain sensation)

Brain injury can be caused by __________, _____________, and _____________

cerebral edema, hypoxia, ischemia

concepts of hypoxia and ischemia, and results of anaerobic metabolism causing

production of lactic acid, buildup of gluconate & calcium

Calcium cascade

Excess intracellular calcium leads to a series of reactions resulting in the release of intracellular enzymes that cause neuronal injury and eventual deathglut

if blood flow isn't properly restored, permanent brain damage will result within ______________ minutes from the effects of calcium cascade

5 minutes

glutamate

The most common neurotransmitter in the brain. Excitatory.

Glutamate malfunction (excess)

happens in the presence of ischemia, it floods the ECF causing calcium to move into the cell, damaging brain tissue

Manifestations of ICP

Changes in LOC, behavioral changes, headache, nausea and projectile vomiting, pupils sluggish or fixed, motor function declines, vital signs change, Cushing's triad, seizures