PSYCHODYNAMICS OF DISEASES

STRESS

internal stressors external stressors acute time limited-such as studying for

final examination chronic intermittent-such as daily

hassles chronic enduring- that persist over time

such as chronic illness and disability.

AUTONOMIC NERVOUS SYSTEM

SYMPATHETIC NERVOUS SYSTEM Parasympathetic system

FLIGHT FIGHT RESPONSE

INCREASED PULSE INCREASED PERISTALSISPERIPHERAL VASOCONSTRICTION INCREASED G.I SECRETIONINCREASED RESPIRATION DECREASED PULSEDILATATION OF PUPILS FORMATION OF GLYOCOGENINCREASED BLOOD SUGAR

PHYSIOLOGICAL RESPONSE TO STRESS

• health is dynamic process rather than something static.

• the healthy person is reacting constantly to the stimuli & adjusting to it

• In nursing there are balancing of various factors:- biological psychological social cultural economic

EQUILIBRIUM THEORY

oBehaving in a realistic & responsive manner to the world around you

oCapable of experiencing a wide range of feelings

oEntering into lasting & satisfying human relationships

oWorking creativity & effectively

Four components of normal psychological equilibrium

CELL

ORGAN

ORGAN SYSTEM

HUMAN

EXTERNA L ENIRONMENT

TISSUE

Model of equilibrium

• It assist nurses to identify the stressors.• It help the nurse to predict

individual response.• Nurse can use this model to

assist patient in strengthening healthy coping & in adjusting unhealthy response.

MODELS OF STRESSMODELS OF STRESS

Stress may considered as response.Acc. to Selye stress response is

characterized by a chain or pattern of physiological events called GAS.

The General Adaptation Syndrome (GAS) is physiological response of the body towards stress.

It involves the autonomic nervous system

& the endocrine system

RESPONSE BASED MODEL

Three stages of stress :-

ALARM STAGE RESISTANCE STAGE EXHAUSTION STAGE

increased mental activityDilated pupilsBronchiolar dilatationIncreased respiratory rateIncreased heart rateIncreased glucoseIncreased cardiac outputIncreased blood pressureIncreased blood flow to the skeletal muscles

CHARACTERSTICS

the response is localized. it does not involve entire bodythe response is adaptivethe response is short termthe response is restorative

this response is a localized response of the CNS to pain. it is an adaptive response and protects tissues from further damage . the response involves a sensory, motor response.

Example:- reflex removal of hand from a hot surface

SECOND PHASE

INFLAMMATORY RESPONSE

FIRST PHASE THIRD PHASE

Injury site

Narrowing of blood vessels

histamine

WBCs

Combat infect

Wound

Exudates

Cut or surgicallyincised

Regeneration

Damaged tissues

Scar formation

Healing

MENTAL STATEInability to concentrate Poor judgment Racing thoughts Moodiness Agitation Irritability Loneliness

INDICATORS OF STRESSINDICATORS OF STRESS

Constant worrying Negativity Restlessness Quick temper Sense of being overwhelmed Unhappiness Fearful Anxiousness Indecisiveness Inability to relax Feeling on edge

Indicators contd….

Physical & behavioral indicators

Headache Muscle tensionNausea Insomnia Acne breakoutDiarrheaLoss of sex deriveFrequently being sickDizzinessWeight gain

Change in appetiteNeglectDrug useNail bitingExcessive spendingTooth grindingExcessive exerciseOverreactionSleeping to much or littleStarting fight

indicators contd….

MANAGEMENTMANAGEMENT Improving

Psychological response

Improving developmental response

Improving intellectual response

Promoting healthy life style

Teaching relaxation techniques

Family factorsEnhancing social

supportEmotional

behavioral issues

• It is also referred to coping mechanism

• The most imp nursing intervention is to enhance the coping mechanism of the disease person

• Mc closkey & bulecheck(1999) identifies “ coping enhancement” as a nursing intervention and defined it as “assisting a patient to adapt to perceive stressors, changes or threats that interfere with meeting demands and rules

PSYCHOLOGICAL RESPONSE

Trying to be optimistic about the outcome

Using social supportUsing spiritual resourcesTrying to accept the situation

Trying to maintain control over the feelings

ACC TO NURSING RESEARCH (JALOWIEC 1993)

Psychological response contd ……….

Psychological response

Constructive Destructive

Psychological response contd ……

COPING STRATEGIES

Problem focused Emotion focused Long term Short term

• Prolonged stress can affect the developmental tasks.• It can also lead to maturational crisis.• If the parent prevent young child from developing a sense of autonomy the child may experience stress.

DEVELOPMENTAL RESPONSEDEVELOPMENTAL RESPONSE

• Stress effect the short term memory.• A person ability to acquire new knowledge or skills may also be impaired.• The client is unable to learn new skills or disease process.

INTELLECTUAL RESPONSE

• Regular exercise• Adequate rest• Nutrition diet• Positive lifestyle• Stop smoking, alcohol• Time management• Meditation

PROMOTING HEALTHY LIFESTYLE

TEACHING RELAXATION TECHNIQUETEACHING RELAXATION TECHNIQUE

Quiet environment

Comfortable position

Passive attitude

Mental device

• Breathing exercises

• Massage• Imagery• Yoga• Meditation• Therapeutic

touch• Music therapy• Laughter

therapy

TYPES OF RELAXATION THERAPY

• Lowered B.P• Lowered heart rate• Dec cardiac dysrhythmia• Dec oxygen consumption• Dec muscle tension• Lowered metabolic rate• Improved concentration• Improved ability to cope with stress

CHANGES RESULTING FROM RELAXATION

Do the assessment of

the family .Major life events

should be explored.Family coping

strategies. Encourage the

family members to stay

with pt.

FAMILY FACTORS

• Individual personality involves a complex relationship among many factors.

• The emotional issues determined by examine the client’s current lifestyle, stressors, prior experience with stressors, past successful coping mechanism

EMOTIONAL BEHAVIORAL ISSUES

• Kozier & Erb’s, fundamental of nursing; 8th edition; 1067:71.

• Joyce M black, Medical surgical nursing; 5th edition; 21:25

• Potter & Perry, Fundamental of nursing; 5th edition; 645:55

• Brunner & Suddarth , Medical surgical nursing; 10th edition; 80:96

• Donald & smelter, psychiatry essential for clinical practice,1983 edition; 2:3

• Nightingale nursing times ,Vol I,issue-8, Nov 2005; 27

• Prism nursing practice, journal of clinical Nsg `education,vol-II,no-2 Oct 07; 155:60

• The journal of Nursing,Vol I, no I, march 2005; 1:6

References

PHYSICAL RESPONSE TO STRESS

According to Hans Selye’s According to Hans Selye’s General Adaptation Model, the General Adaptation Model, the body reacts to stress in the body reacts to stress in the stages depicted belowstages depicted below..

FUNDAMENTALS OF PATHOPHYSIOLOGY

PHYSICAL OR PSYCHOLOGICAL STRESSORALARM REACTION (FIGHT-OR-FLIGHT RESPONSE)

* Arousal of the central nervous system begins.* Epinephrine and norepinephrine, along with other hormones, are released, causing an increase in heart rate, force of heart contractions, oxygen intake, and mental activity.

RESISTANCE* The body responds to the stressor and attempts to return to homeostasis.* Coping mechanisms come into play.

RECOVERY* If stress ceases, the body should return to a normal state, leading to recovery.

EXHAUSTION* The body can no longer produce hormones as it did in the alarm stage.* Organ damage begins.

KEY FACTS ABOUT THE KEY FACTS ABOUT THE HEMATOLOGIC SYSTEMHEMATOLOGIC SYSTEM

Blood is a major body tissue Blood is a major body tissue Plasma factors and platelets control clottingPlasma factors and platelets control clotting Erythrocytes carry oxygen; remove carbon Erythrocytes carry oxygen; remove carbon

dioxidedioxide Leukocytes act in inflammatory and immune Leukocytes act in inflammatory and immune

responsesresponses Plasma carries antibodies and nutrients to Plasma carries antibodies and nutrients to

tissues and carries away wastetissues and carries away waste Hematopoiesis occurs primarily in marrowHematopoiesis occurs primarily in marrow Average person has 5 to 6 L of circulating bloodAverage person has 5 to 6 L of circulating blood

• Bone marrow cells particularly vulnerable Bone marrow cells particularly vulnerable to physiologic changesto physiologic changes

• Disease can affect structure or Disease can affect structure or concentration of any hematologic cellconcentration of any hematologic cell

CARDIOVASCULAR SYSTEMCARDIOVASCULAR SYSTEM• Begins when the fetus is barely 4 weeks old; last system to cease Begins when the fetus is barely 4 weeks old; last system to cease

activityactivity• Helps define presence of lifeHelps define presence of life• Comprises the heart, arteries, veins, and lymphaticsComprises the heart, arteries, veins, and lymphatics• Serves as the body’s transport systemServes as the body’s transport system• Brings oxygen and nutrients to cells, removes metabolic waste Brings oxygen and nutrients to cells, removes metabolic waste

products, and carries hormonesproducts, and carries hormones• Commonly called the circulatory systemCommonly called the circulatory system• Pulmonary circulation: blood picks up oxygen and eliminates carbon Pulmonary circulation: blood picks up oxygen and eliminates carbon

dioxidedioxide• Systemic circulation: blood carries oxygen and nutrients to active cells Systemic circulation: blood carries oxygen and nutrients to active cells

and transports waste for excretionand transports waste for excretion• Blood circulates through arteries, veins, and capillariesBlood circulates through arteries, veins, and capillaries

RENAL SYSTEMRENAL SYSTEMKey facts about the renal systemKey facts about the renal system• Kidneys produce and excrete urine to maintain homeostasisKidneys produce and excrete urine to maintain homeostasis• Ureters transport urine to bladder from kidneysUreters transport urine to bladder from kidneys• Bladder: reservoir for urine until it leaves body through Bladder: reservoir for urine until it leaves body through

urethraurethra

PATHOPHYSICAL CHANGESPATHOPHYSICAL CHANGES• Filtration and reabsorption changes affect total filtration Filtration and reabsorption changes affect total filtration

efforteffort• Capillary pressure and interstitial fluid colloid osmotic Capillary pressure and interstitial fluid colloid osmotic

pressure affect filtrationpressure affect filtration• Interstitial fluid pressure and plasma colloid osmotic pressure Interstitial fluid pressure and plasma colloid osmotic pressure

affect filtrationaffect filtration• Altered renal perfusion; disease affecting vessels, glomeruli, Altered renal perfusion; disease affecting vessels, glomeruli,

tubules; obstruction to urine slow the GFRtubules; obstruction to urine slow the GFR

RESPIRATORY SYSTEMRESPIRATORY SYSTEMKEY FACTS ABOUT THE RESPIRATORY SYSTEMKEY FACTS ABOUT THE RESPIRATORY SYSTEM

• Major function is gas exchangeMajor function is gas exchange• Upper airway allows airflow into lungs; warm, humidify, filter Upper airway allows airflow into lungs; warm, humidify, filter

airair• Lower airway consists of trachea, mainstream bronchi, Lower airway consists of trachea, mainstream bronchi,

secondary bronchi, bronchioles, terminal bronchiolessecondary bronchi, bronchioles, terminal bronchioles• Structures are anatomic dead spaces, function only as Structures are anatomic dead spaces, function only as

passageways for moving air into and out of the lungspassageways for moving air into and out of the lungs• Distal to terminal bronchioles are acinus- respiratory Distal to terminal bronchioles are acinus- respiratory

bronchioles, alveolar ducts, alveolar sacs.bronchioles, alveolar ducts, alveolar sacs.• Bronchioles and ducts function as conduitsBronchioles and ducts function as conduits• Alveoli: chief units of gas exchangeAlveoli: chief units of gas exchange• Clearance mechanisms: cough reflex and mucociliary system.Clearance mechanisms: cough reflex and mucociliary system.

KEY FACTS ABOUT THE RESPIRATORY SYSTEMKEY FACTS ABOUT THE RESPIRATORY SYSTEM((continuedcontinued))

• Lower airway protects lungs with defense mechanismsLower airway protects lungs with defense mechanisms• Respiration delivers inspired air to lower respiratory tract and alveoliRespiration delivers inspired air to lower respiratory tract and alveoli• Contraction and relaxation of respiratory muscles moves air into and out Contraction and relaxation of respiratory muscles moves air into and out

of lungsof lungs• Normal expiration is passiveNormal expiration is passive• Adult lung contains 300 million alveoli; each supplied by many capillariesAdult lung contains 300 million alveoli; each supplied by many capillaries• To reach capillary lumen, oxygenmust cross alveolar capillary membraneTo reach capillary lumen, oxygenmust cross alveolar capillary membrane• The pulmonary alveoli promote gas exchange by diffusion The pulmonary alveoli promote gas exchange by diffusion • Circulating blood delivers oxygen to cells for metabolism and transport Circulating blood delivers oxygen to cells for metabolism and transport

metabolic wastes and COmetabolic wastes and CO22 back to lungs back to lungs• COCO2 2 reaches alveolar capillaries, diffuses into the alveoli; removed from reaches alveolar capillaries, diffuses into the alveoli; removed from

the alveoli during exhalationthe alveoli during exhalation

ENDOCRINE SYSTEMENDOCRINE SYSTEMKEY FACTS ABOUT THE ENDOCRINE SYSTEMKEY FACTS ABOUT THE ENDOCRINE SYSTEM

• Consists of glands, specialized cell clusters, Consists of glands, specialized cell clusters, hormones, tissueshormones, tissues

• Glands and cell clusters secrete hormones, chemical Glands and cell clusters secrete hormones, chemical transmitters in response to stimulationtransmitters in response to stimulation

• With nervous system, regulates metabolic activities, With nervous system, regulates metabolic activities, maintains internal homeostatismaintains internal homeostatis

• Hormones connect with receptors in target tissuesHormones connect with receptors in target tissues• Resulting hormone-receptor complex triggers target Resulting hormone-receptor complex triggers target

cell’s responsecell’s response

HORMONAL REGULATIONHORMONAL REGULATION

• Hypothalamus helps control some endocrine glandsHypothalamus helps control some endocrine glands• Neural stimulation of posterior pituitary causes secretion Neural stimulation of posterior pituitary causes secretion

of ADH, oxytocinof ADH, oxytocin• Hypothalamic hormones stimulate pituitary gland to Hypothalamic hormones stimulate pituitary gland to

synthesize and release trophic hormones.synthesize and release trophic hormones.• Trophic hormones stimulate adrenal cortex, thyroid Trophic hormones stimulate adrenal cortex, thyroid

gland, gonads.gland, gonads.• Hypothalamic hormones stimulate pituitary to release or Hypothalamic hormones stimulate pituitary to release or

inhibit release of effector hormonesinhibit release of effector hormones• Negative feedback system regulates endocrine systemNegative feedback system regulates endocrine system• Simple feedback occurs when level of one substance Simple feedback occurs when level of one substance

regulates secretion of a hormoneregulates secretion of a hormone

RHYTHMSRHYTHMS • Circadian rhythm increases and decreases hormone levels by Circadian rhythm increases and decreases hormone levels by

time of daytime of day• Infradian rhythm” biorhythm that repeats in patterns > 24 Infradian rhythm” biorhythm that repeats in patterns > 24

hourshours

HORMONAL EFFECTSHORMONAL EFFECTS• Oxytocin: stimulates contractionof uterus, milk- letdown Oxytocin: stimulates contractionof uterus, milk- letdown

reflexreflex• ADH: controls concentration of body fluidsADH: controls concentration of body fluids• Proclactin: controls milk secretion , GHProclactin: controls milk secretion , GH• GH: triggers growthGH: triggers growth• Iodinated hormones: affect growth, developmentIodinated hormones: affect growth, development• PTH: regulates calcium, phosphate metabolism.PTH: regulates calcium, phosphate metabolism.

REPRODUCTIVE SYSTEMREPRODUCTIVE SYSTEMKEY FACTS ABOUT THE REPRODUCTIVE SYSTEMKEY FACTS ABOUT THE REPRODUCTIVE SYSTEM

• Must function properly to ensure survival of speciesMust function properly to ensure survival of species• Male reproductive system produces sperm, delivers Male reproductive system produces sperm, delivers

them to female reproductive tractthem to female reproductive tract• Female reproductive system produces ova, nurtures Female reproductive system produces ova, nurtures

and protects embryo and fetus; delivers it at birthand protects embryo and fetus; delivers it at birth• Functioning is determined by anatomic structure, Functioning is determined by anatomic structure,

hormonal, neurologic, vascular, psychogenic factorshormonal, neurologic, vascular, psychogenic factors

FLUIDS AND ELECTROLYTESFLUIDS AND ELECTROLYTES

Key facts about fluid balance and exchangeKey facts about fluid balance and exchange

• Kidneys regulate fluid componentsKidneys regulate fluid components• Fluid inside each cell is ICF; blood plasma and other Fluid inside each cell is ICF; blood plasma and other

fluid in the spaces outside cells is ECFfluid in the spaces outside cells is ECF• ECF transport nutrients and oxygen to cells and ECF transport nutrients and oxygen to cells and

carries away waste products for eliminationcarries away waste products for elimination• Fluid is moved out of vessels by hydrostatic pressure Fluid is moved out of vessels by hydrostatic pressure

of blood and osmotic pressure and hydrostatic of blood and osmotic pressure and hydrostatic pressure of interstitial fluidpressure of interstitial fluid

• When the capillary wall is normal, fluid escapes at When the capillary wall is normal, fluid escapes at the arteriolar end of the capillary and is returned at the arteriolar end of the capillary and is returned at the venular end.the venular end.

KEY FACTS ABOUT PATHOPHYSIOLOGIC CHANGES IN ACID-BASE KEY FACTS ABOUT PATHOPHYSIOLOGIC CHANGES IN ACID-BASE IMBALANCEIMBALANCE

AcidemiaAcidemia • Arterial pH<7.35 – excess acid in the bloodArterial pH<7.35 – excess acid in the blood• Hydrogen ion content increases Hydrogen ion content increases • Potassium leaves cells to neutralize, causing hypokalemiaPotassium leaves cells to neutralize, causing hypokalemia

Acidosis Acidosis • Systemic increase in hydrogen ion concentrationSystemic increase in hydrogen ion concentration• Occurs when lung can’t eliminate C02, or if diarrhea causes Occurs when lung can’t eliminate C02, or if diarrhea causes

loss of bicarbonate anions or if the kidneys fail to reabsorb loss of bicarbonate anions or if the kidneys fail to reabsorb bicarbonate or secrete hydrogen ionsbicarbonate or secrete hydrogen ions

AlkalemiaAlkalemia• Arterial blood pH> 7.45 – excess base in the bloodArterial blood pH> 7.45 – excess base in the blood• Potassium moves into cells to neutralize, causing hypokalemiaPotassium moves into cells to neutralize, causing hypokalemia

AlkalosisAlkalosis• Bodywide decrease in hydrogen ion concentrationBodywide decrease in hydrogen ion concentration• Caused by hyperventilation and loss of nonvital acids during Caused by hyperventilation and loss of nonvital acids during

vomiting or from excessive ingestion of basevomiting or from excessive ingestion of base

CompensationCompensation• Lungs, kidneys, other chemical buffer systems work together Lungs, kidneys, other chemical buffer systems work together

to maintain normal plasma pH rangeto maintain normal plasma pH range• Buffer systems consists of a weak acid and corresponding Buffer systems consists of a weak acid and corresponding

basebase• Four major buffers or buffer systems work to restore normal Four major buffers or buffer systems work to restore normal

pHpH• The kidneys normalize pH by altering handling of hydrogen The kidneys normalize pH by altering handling of hydrogen

and bicarbonate ionsand bicarbonate ions• Responds in hours or days to respiratory alteration of pHResponds in hours or days to respiratory alteration of pH• Compensation by the lungs regulates respiratory rate to Compensation by the lungs regulates respiratory rate to

adjust pH; respiration increases or decreases to raise or lower adjust pH; respiration increases or decreases to raise or lower PacoPaco22 levels levels

CHARACTERISTIC OF RESPIRATORY ACIDOSISCHARACTERISTIC OF RESPIRATORY ACIDOSIS

• Characterized by alveolar ventilationCharacterized by alveolar ventilation• Patient can’t clear enough C0Patient can’t clear enough C022 from the body from the body • PacoPaco22 buildup causes hypercapnia (Paco buildup causes hypercapnia (Paco22 > 45 mm Hg) and > 45 mm Hg) and

acidosisacidosis• May be acute or chronicMay be acute or chronic

CAUSESCAUSES • Opioids Opioids • General anestheticsGeneral anesthetics• HypnoticsHypnotics• Injury to the medullaInjury to the medulla• Reduced cardiac outputReduced cardiac output• Neuromuscular or respiratory diseaseNeuromuscular or respiratory disease• Sleep apnea Sleep apnea

HOW IT HAPPENSHOW IT HAPPENS• Pulmonary ventilation decreases, PacoPulmonary ventilation decreases, Paco22 increases, and C0 increases, and C022 levels rise in all levels rise in all

tissuestissues• Respiration increases; pH falls Respiration increases; pH falls • Respiratory mechanisms fail; kidney buffer mechanisms take over, then Respiratory mechanisms fail; kidney buffer mechanisms take over, then

failfail• Electrolyte imbalances critically depress neurologic and cardiac functions Electrolyte imbalances critically depress neurologic and cardiac functions

KEY SIGNS AND SYMPTOMSKEY SIGNS AND SYMPTOMS• RestlessnessRestlessness• ConfusionConfusion• ApprehensionApprehension• SomnolenceSomnolence• Asterixis Asterixis • ComaComa• HeadacheHeadache• Dyspnea and tachypneaDyspnea and tachypnea• PapilledemaPapilledema

GASTROINTESTINAL SYSTEMGASTROINTESTINAL SYSTEM

KEY FACTS ABOUT THE GI SYSTEMKEY FACTS ABOUT THE GI SYSTEM• Supplies essential nutrients Supplies essential nutrients • Serves to digest food and eliminate wasteServes to digest food and eliminate waste• Profoundly affects quality of lifeProfoundly affects quality of life• Two major components: GI tract and accessory organsTwo major components: GI tract and accessory organs• Malfunction in system can produce life – threatening metabolic Malfunction in system can produce life – threatening metabolic

effectseffects

GI TRACTGI TRACT• Hollow muscular tube from mouth to anusHollow muscular tube from mouth to anus• Oral cavity, pharynx, esophagus, stomach, small and large intestineOral cavity, pharynx, esophagus, stomach, small and large intestine• Peristalsis propels ingested, material; sphincters prevent refluxPeristalsis propels ingested, material; sphincters prevent reflux

PATHOPHYSIOLOGIC CHANGESPATHOPHYSIOLOGIC CHANGES• Disorders typically nonspecific, reflect disruption in functionsDisorders typically nonspecific, reflect disruption in functions

NERVOUS SYSTEMNERVOUS SYSTEMKEY FACTS ABOUT THE NERVOUS SYSTEMKEY FACTS ABOUT THE NERVOUS SYSTEM

• Coordinates and organizes functions of all body Coordinates and organizes functions of all body systemssystems

• Has three main divisions: CNS, peripheral nervous Has three main divisions: CNS, peripheral nervous system, ANSsystem, ANS

• Neurons transmit nerve impulses through bodyNeurons transmit nerve impulses through body• Most neurons have several dendrites, only one axonMost neurons have several dendrites, only one axon• Three types: sensory, motor, and interneuronsThree types: sensory, motor, and interneurons• Nervous system disorders can cause signs and Nervous system disorders can cause signs and

symptoms in any body system; hard to diagnosesymptoms in any body system; hard to diagnose

REVIEWING THE CNSREVIEWING THE CNS• Cerebrum – frontal lobe, temporal lobe, parietal lobe, Cerebrum – frontal lobe, temporal lobe, parietal lobe,

occipital lobeoccipital lobe• Cerebellum – maintains muscle tone, coordinationCerebellum – maintains muscle tone, coordination• Brain stem – pons, midbrain, medulla oblongataBrain stem – pons, midbrain, medulla oblongata• Primitive structures – thalamus, hypothalamus, limbic system, Primitive structures – thalamus, hypothalamus, limbic system,

RASRAS• Spinal cord – relays sensory, motor impulsesSpinal cord – relays sensory, motor impulses

REVIEWING THE PERIPHERAL NERVOUS SYSTEMREVIEWING THE PERIPHERAL NERVOUS SYSTEM• Cranial nerves – Cranial nerves – 112 pairs: olfactory, optic, oculomotor, 2 pairs: olfactory, optic, oculomotor,

trochlear, trigeminal, abducens, facial, acoustic, trochlear, trigeminal, abducens, facial, acoustic, glossopharyngeal, vagus, spinal accessory, hypoglossalglossopharyngeal, vagus, spinal accessory, hypoglossal

• Spinal nerves - 3Spinal nerves - 311 pairs with sensory and motor neurons pairs with sensory and motor neurons• ANS – innervates internal organs; sympathetic nervous ANS – innervates internal organs; sympathetic nervous

systemsystem

PATHOPHYSIOLOGIC CHANGESPATHOPHYSIOLOGIC CHANGES• Typically involve alteration in arousal, cognition, movement, Typically involve alteration in arousal, cognition, movement,

muscle tone, homeostatic mechanisms or painmuscle tone, homeostatic mechanisms or pain• Most cause more than one alterationMost cause more than one alteration• One alteration may lead to anotherOne alteration may lead to another

KEY FACTS ABOUT AROUSALKEY FACTS ABOUT AROUSAL• Level of consciousness or state of awarenessLevel of consciousness or state of awareness

SEVERAL MECHANISMS CAN ALTER AROUSALSEVERAL MECHANISMS CAN ALTER AROUSAL• Direct destruction of RAS and pathwaysDirect destruction of RAS and pathways• Destruction of brain stemDestruction of brain stem• Compression of RAS by disease processCompression of RAS by disease process• Mechanisms may result from structural, metabolic, or Mechanisms may result from structural, metabolic, or

psychogenic disturbancespsychogenic disturbances