Fluid Imbalances
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Transcript Fluid Imbalances
Fluid, Electrolyte, and
Acid-Base Balances
Chapter 41
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Distribution of Body Fluids
Adult human body made up of about
60% water
Body holds fluid in 2 basic
compartments
Extracellular
Intracellular
Distribution of fluid b/w 2 compartments
must remain relatively constant
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Distribution of Body Fluids
Extracellular
Interstitial fluid
surrounds
the cells
Intravascular fluid
liquid
portion of blood or plasma
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Distribution of Body Fluids
Transcellular fluid
Cerebrospinal
column
pleural
cavity
Lymph system
Joints
Eyes
Intracellular
Inside cells
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Inside the
Cell:intracellular
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Composition of Body Fluids
Water
Full-term neonate
80%
Premature infant
90
body weight is water
% of body weight is water
Amount of water % decreases with age
until puberty
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Composition of Body Fluids
Skeletal muscle cells hold much of water, fat
cells contain little water
Women
have lower ration of water content
Risk of suffering an imbalance increases with
age
Skeletal
muscle mass declines
Proportion of fat within body increases
After age 60, water content drops to about 45%
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Electrolytes:
Anions and Cations
When electrolytes are melted or dissolved
into separates into ions and is able to
carry an electrical current
Anions
Negatively charged electrolytes
Cations
Positively charged electrolytes
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Fluid Types
Isotonic
Saline solution (0.9% Normal Saline)
Nearly equals the concentration of sodium in
the blood
Hypotonic
Lower solute concentration than another
solution
Fluid from hypotonic solution would shift into
the second solution until the two solutions had
equal concentrations
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Fluid Types
½ Normal Saline (0.45% Normal Saline)
Concentration of sodium is lower than concentration of
sodium into patient’s blood
Moves fluid into the cells, causing them to enlarge
Hypertonic
Has a higher concentration than another solution
Fluid from second solution would shift into hypertonic
solution until equilibrium
Dextrose 5% saline solution (D5NS)
Concentration of solutes in solution is greater than
concentration of solutions in patients blood
Pulls fluid from cells, causing them to shrink
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Movement of Body Fluids
Osmosis
Fluid moves passively from areas with more
fluid (and fewer solutes) to areas with less
fluid (and more solutes) through a semipermeable membrane
Diffusion
Solutes move from an area of higher
concentration to lower concentration
across a semi-permeable membrane
Passive transport
Doesn’t
require
energy
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Movement of Body Fluids
Filtration
Water and diffusible substances move from
area of higher pressure to lower pressure
Movement occurs in capillary beds
Results
from blood pushing against the walls of the
capillary (hydrostatic pressure).
Forces fluids and solutes through capillary wall
When
the hydrostatic pressure increases inside a
capillary is greater than the pressure in
surrounding interstitial space, fluids and solute
inside the capillary are forced out into interstitial
space.
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Movement of Body Fluids
When pressure inside capillary is less than
pressure outside of it, fluids and solutes move
back into capillary
Reabsorption
Prevents
too much fluid from leaving capillaries no
matter how much hydrostatic pressure exists
When fluid filters through a capillary, albumin
(protein) remains behind in the diminishing volume
of water.
Water magnet
Has an osmotic effect
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Movement of Body Fluids
Plasma colloid osmotic pressure
Osmotic
or pulling force of albumin in the
intravascular space
As long as capillary blood pressure (hydrostatic pressure)
exceeds plasma colloid osmotic pressure, water and
solutes can leave capillaries and enter interstitial fluid.
When osmotic pressure falls below plasma colloid osmotic
pressure m water and diffusible solutes return to
capillaries
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Movement of Body Fluids
Active transport
Requires metabolic activity and expenditure
of energy
ATP
(adenosine triphosphate)
ATP is stored in all cells
Solutes move from area of lower
concentration to an area of higher
concentration
Enhanced by carrier molecules within a cell
Glucose
enters cell after it binds with insulin
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Regulation of Body Fluids
Homeostasis
Physiological balance
Fluid intake (adult: 2200 to 2700 ml/day)
Regulated by thirst mechanism
Losing body fluids or eating highly salty foods leads to
increase in extracellular fluid osmolality.
This increase leads to drying of mucus membranes in
mouth
Which stimulates thirst center in hypothalamus
Infants, clients with neurological or psychological
problems and some older adults at risk for
dehydration
Unable to perceive thirst mechanism
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The Kidneys
Play vital role in fluid balance
Nephron
Workhorse of kidney-forms urine
Consists of a glomerulus and a tubule
The tubule ends in a collecting duct
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The Kidneys
Glomerulus
Cluster
of capillaries that filters blood
Surrounded by Bowman’s capsule
Vascular cradle
Capillary pressure forces fluid through the
capillary walls and into Bowman’s capsule at the
proximal end of the tubule
Along length of tubule, water and electrolytes are
either excreted or retained
According
to the body’s needs
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The Kidneys
If
less fluid is needed, less is reabsorbed and excreted
If more fluid is needed, more fluid is retained
Na and K (electrolytes) are either filtered or
reabsorbed throughout this same area
The resulting filtrate flows through tubule into
collecting ducts and eventually into the bladders as
urine
The nephron filters about 125ml blood every
minute (180L/day)
Glomerular
filtration rate
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The Kidneys
Leads
to production of 1 to 2 L of urine/day
Nephrons reabsorb remaining 178L or more fluid
If body loses even 1-2% of its fluid, the
kidneys take steps to conserve fluid
Kidneys
respond by excreting more dilute urine
Kidneys must continue to excrete at least
30ml of urine every hour to eliminate body
waste
Urine excretory rate less than 30ml/hr
usually indicates renal pathology
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Hormonal Regulation
ADH (antidiuretic hormone) (vasopressin)
“water retainer”
Produced by hypothalamus
Stored and released by posterior pituitary
gland
Job:
Restores
blood volume by reducing diuresis and
increasing water retention
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Hormonal Regulation
Aldosterone
Released by adrenal cortex in response to increased
plasma potassium levels or to counteract hypovolemia
Release of aldosterone acts as a volume regulator
Renin-angiotensin-aldosterone system
Proteolytic enzyme secreted by kidney
Responds to decreased renal perfusion 2ndary to
decrease in extracellular volume
Amount of renin secreted depends on blood flow and level of
Na in bloodstream.
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Hormonal Regulation
If
blood flow to kidneys diminishes, (hemorrhaging)
or if amount of Na reaching the glomerulus, more
renin is secreted.
This causes vasoconstriction with a subsequent
increase in blood pressure
If blood flow to kidneys increases, or amount of Na
reaching glomerulus increased, less renin is
secreted
Drop-off in renin secretion reduces vasoconstriction and
helps to normalize blood pressure
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Hormonal Regulation
Fluid output
Occurs through 4 organs of water loss
Kidneys
Skin
Lungs
GI
tract
Insensible water loss
Can’t be measured or seen
Evaporation (skin)
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Hormonal Regulation
Respiratory rate and depth
Tachypnea-increased fluid loss
Bradypnea-decreased fluid loss
Fever
Losses from skin and lungs
Sensible water loss
Urination
Defecation
Wounds
Excessive
perspiration (perceivable)
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ELECTROLYTE IMBALANCES
SODIUM (Na+)
Sodium (Na+)
Most abundant at 90% in extracellular
fluid
Help maintain fluid balance
Serum
osmalility
Nerve impulse transmission
Regulation of acid-base balance
135 to 145 mEq/L
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ELECTROLYTE IMBALANCES
SODIUM: Hyponatremia
Actual decrease: pt has inadequate intake
of sodium or excess of sodium
Relative decrease: sodium is not lost from
body but leaves intravascular space and
moves to the interstitial space (third
spacing)
Another relative cause of decrease occurs
when plasma volume increases (fluid
overload) causing dilution effect
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ELECTROLYTE IMBALANCES
SODIUM: Hyponatremia
Prevention
Administration of sodium for patients at risk is
usually by IV route
NPO
Excessive diaphoresis
Diuretics
GI suction
Freshwater near drowning
Decreased aldosterone
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ELECTROLYTE IMBALANCES
SODIUM: Hyponatremia
Prevention
Replace both sodium and water in the following
patients experiencing
High fevers
Strenuous exercise or physical labor, esp.
with heat excess
Especially dangerous for elderly
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ELECTROLYTE IMBALANCES
SODIUM: Hyponatremia
Signs & Symptoms
Mental status changes, including
disorientation, confusion and personality
changes due to cerebral edema
Postural hypotension
Abdominal cramping
Tachycardia
N&V
Weakness
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ELECTROLYTE IMBALANCES
SODIUM: Hyponatremia
Medical Treatment
Focus is to resolve underlying cause &
replace lost sodium
IV saline ordered if fluid overload is not
present
may be 0.9 NS (isotonic) or 3%BS
(hypertonic) depending on severity
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ELECTROLYTE IMBALANCES
SODIUM: Hypernatremia
Serum sodium level is above 145 mEq/L
Ingestion of large amounts concentrated
salts
Diabetes insipidus
Increased sensible or insensible water loss
Water deprivation
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ELECTROLYTE IMBALANCES
SODIUM: Hypernatremia
Prevention
Not as simple as hyponatremia
Most are a result of an acute or chronic illness
Carefully regulate IV fluids
Signs & Symptoms
Thirst usually first symptom
Agitation
Dry and flushed skin
Restlessness
Irritability
Convulsions
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ELECTROLYTE IMBALANCES
SODIUM: Hypernatremia
Medical Treatment
If fluid imbalance present..correct first
If kidneys not excreting…diuretic if
kidney is functional
Dialysis may be need if not functional
I&O
Daily weights
Treat cause if known
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ELECTROLYTE IMBALANCES
Potassium (K+)
Normal serum value = 3.5-5 mEq/L
Most common electrolyte in the ICF
compartment
Regulates many metabolic activities
Necessary for
Transmission and conduction nerve impulses
Glycogen deposits in liver and skeletal muscle
Skeletal and smooth muscle contraction
Minimal changes in value cause major
changes in body
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ELECTROLYTE IMBALANCES
Potassium: Hypokalemia
Serum potassium level below 3.5 mEq/L
Most cases…inadequate intake or excessive loss of
K+ via the kidneys
Most often occurs as result of medications
K+ losing diuretic… Furosemide (Lasix)
Digitalis preparations…Digoxin (Lanoxin)
GI tract losses
Vomiting, diarrhea, prolonged GI suctioning
Major Surgery and hemorrhage can cause deficit
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ELECTROLYTE IMBALANCES
Potassium: Hypokalemia
Prevention
Administer K+ supplements prior to
major surgery in IV fluids
Encourage foods high in K+ if on
medications that causes K+ loss
Digitalis must be closely monitored
hypokalemia
can enhance action of
digitalis causing digitalis toxicity
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ELECTROLYTE IMBALANCES
Potassium: Hypokalemia
Signs & Symptoms
Muscle cramping
Decreased muscle tone
Shallow, ineffective respirations
Pulse weak, irregular, thready due to heart
muscle depletion of K+
Decreased bowel sounds
Major danger of dysrhythmia leading to cardiac
arrest
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ELECTROLYTE IMBALANCES
Potassium: Hypokalemia
Treatment:
Mild to moderate kypokalemia
Oral supplements
Severe Hypokalemia
IV K+ supplements
Add only after pt voids to assure kidney has ability to rid the
body of excess K+
Never give IV push
Monitor serum values closely
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ELECTROLYTE IMBALANCES
Potassium: Hyperkalemia
Serum potassium greater than 5 mEq/L
Renal failure
Excessive intake of oral or IV supplements
Use of K+ sparing diuretics (Aldactone)
Massive cellular damage
Burns
Trauma
Fluid volum deficit
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ELECTROLYTE IMBALANCES
Potassium: Hyperkalemia
Prevention
Monitor
serum electrolytes values in pt
receiving supplements
Monitor pt for s/s of imbalance
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ELECTROLYTE IMBALANCES
Potassium: Hyperkalemia
Signs & symptoms
Usually
occur in hospitalized pt or chronic
conditions with treatment
Muscle twitches & Cramps Progressing to
Muscular weakness
Diarrhea
Slow,irregular heart rate
Decreased blood pressure
Anxiety
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ELECTROLYTE IMBALANCES
Potassium: Hyperkalemia
Medical Treatment
Mild, chronic
Limit K+ rich foods
Stop K+ supplements
Administer K+ losing diuretic if kidneys healthy
During treatment of moderate to severe
hyperkalemia pt should be hospitalized and
on cardiac monitor
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ELECTROLYTE IMBALANCES
Calcium (Ca++)
Normal Value = 4.5-5.5 mEq/L
Stored in bones, teeth, plasma and body cells
Necessary for:
Bone and teeth formation
Blood clotting
Hormone secretion
Cardiac conduction
Transmission of nerve impulses
Muscle contraction
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ELECTROLYTE IMBALANCES
Calcium: Hypocalcemia (Ca++)
Serum calcium level below 4.5 mEq/L
Postmenopausal women are most at risk
Causes brittle, porous bones that are easily
fractured….osteoporosis
Postmenopausal women have decreased estrogen
Immobility or decreased motility contributes to bone
loss in younger women
Patients at highest risk for osteoporosis are thin,
petite, Caucasian women
Pancreatitis
Vitamin D deficienty
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ELECTROLYTE IMBALANCES
Calcium: Hypocalcemia (Ca++)
Prevention
Adequate intake 1000 – 1200 mg
Consume calcium rich food
Take supplements
Tums 240 mg/tab
Vitamin D may be needed if lack of sun
exposure
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ELECTROLYTE IMBALANCES
Calcium: Hypocalcemia (Ca++)
Signs & Symptoms
Pathological fractures
Increased and irregular heart rate
Numbness and tingling of fingers
Hyperactive deep tendon reflexes
Increased GI motility…diarrhea , cramps
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ELECTROLYTE IMBALANCES
Calcium: Hypocalcemia (Ca++)
Two classic signs used to assess for
hypocalcemia
Trousseau’s sign and Chvostek’s sign
Trousseau’s
sign…inflate bp cuff on the arm 1-4
minutes. If pt’s hand and fingers become spastic
and demonstrate palmar flexion ….test is positive
Chvostek’s sign…tap face just below and in front of
ear, facial twitching on that side of face indicates
positive test
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ELECTROLYTE IMBALANCES
Calcium: Hypocalcemia (Ca++)
Medical Treatment
Treat cause
Replace calcium
Oral with or without Vitamin D… if mild or chronic
condition
Administer 1-2 h pc to increase absorption
IV
administration for acute or severe
hypocalcamia
Use calcium gluconate or calcium chloride
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ELECTROLYTE IMBALANCES
Calcium: Hypercalcemia
Ca+
above 5.5 mEq/L
Prolonged Immobilization
Excess intake of calcium or vitamin D
Osteoporosis
Hyperparathyroidism
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ELECTROLYTE IMBALANCES
Calcium: Hypercalcemia
Prevention
Many causes cannot be prevented
Monitor pt receiving calcium supplement
Education of public regarding proper amount
needed as well as dangers of too much calcium
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ELECTROLYTE IMBALANCES
Calcium: Hypercalcemia
Signs & Symptoms
Skeletal muscle weakness
Anorexia, N&V
Decreased LOC
Personality changes
Lethargy
Low back pain
Cardiac arrest
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ELECTROLYTE IMBALANCES
Calcium: Hypercalcemia
Medical Treatment
Severe hypercalcemia
Hospitalize
Cardiac monitor
Administer large amounts of fluids and promote
diuresis if not contraindication by patient condition
Saline infusion most useful to promote excretion
Discontinue
any thiazide diuretic
Use Lasix
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ELECTROLYTE IMBALANCES
Magnesium(Mg++)
Normal value: 1.50-2.5 mEq/L
Magnesium & calcium work together for proper functioning
of excitable cells
Cardiac & nerve cells
An imbalance of magnesium is usually accompanied by
calcium imbalance
Essential for:
Neurochemical activities
Cardiac and skeletal muscle excitability
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ELECTROLYTE IMBALANCES
Magnesium: Hypomagnesemia
Serum magnesium level below 1.5 mEq/L
Malnutrition/Starvation diets
Alcoholism
Inadequate absorption
N&V, diarrhea
Nasogastric drainage
Fistulas
Polyuria
Excessive loss from thiazide diuretics
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ELECTROLYTE IMBALANCES
Magnesium: Hypomagnesemia
Signs & Symptoms similar to hypocalcemia
Positive Trousseau’s and Chvostek’s sign
Muscle tremors
Confusion and disorientation
Treatment
Mg
sulfate is administered IV, calcium may also be
administered
Place on cardiac monitor
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ELECTROLYTE IMBALANCES
Magnesium: Hypermagnesemia
Serum magnesium level above 2.5 mEq/L
Renal failure
Excess oral or parenteral intake
Signs & symptoms
Usually not apparent until level is > 4 mEq/L
Bradycardia, decreased depth of resp.
Hypoactive deep tendon reflexes
Hypotension
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ELECTROLYTE IMBALANCES
Magnesium: Hypermagnesemia
Treatment
Loop diuretics if kidney function properly
IV fluids to increase renal excretion
If renal failure
dialysis
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Regulation of Electrolytes: Anions
Chloride (Cl-)
90-110mEq/L
Major anion in ECF
Regulated by dietary intake and kidneys
Hypochloremia
Vomiting
drainage
or prolonged and excessive NGT
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Regulation of Electrolytes: Anions
Bicarbonate (HCO3-)
22-26 mEq (arterial)
24-30 mEq (venous)
Major chemical base buffer in the body
Found in ECF and ICF
Essential to acid base balance
Kidneys regulate bicarb
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Regulation of Electrolytes: Anions
Phosphate (PO4-)
1.7-4.6 mEq/L
Buffer anion found primarily in ICF
Assisting in acid base regulation
Phosphate and calcium help to develop and
maintain bones and teeth
Calcium and phosphate are inversely
proportional
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Fluid Imbalances
Dehydration: fluid deficit
Elderly people are at highest risk for life threatening
complications resulting from dehydration
Infants are at high risk because they take in &
excrete a large portion of their total body water each
day
Fluid overload: fluid excess
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Fluid Imbalances:
Dehydration
Dehydration
Several types
Isotonic
Hypertonic
Hypotonic
Dehydration occurs when there is not enough fluid in
the body, especially in the blood…..intravascular area
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Fluid Imbalances:
Dehydration
Most common is fluid loss from body
Results in decreased blood volume called
hypovolemia
Fluid loss may occur from
Hemorrhaging
Severe
vomiting
Severe diarrhea
Severely draining wound
Profuse diaphoresis
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Fluid Imbalances:
Dehydration
Burns
Trauma
Surgery
Respiratory disorders
Cancer
CV disease
Diet
Medications
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Fluid Imbalances:
Dehydration
Prevention
Identify patients at high risk
Elderly
Infants
Children
Adequate hydration
Drink enough fluids
Administer IV therapy if unable to take PO
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Fluid Imbalances:
Dehydration
Signs & Symptoms
Thirst is the first symptom in healthy adults
Tachycardia results from heart pumping faster but
not as strongly
Weak rapid pulse
Low blood pressure
Decreased tears
Dry skin
Dry mucous membranes
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Fluid Imbalances:
Dehydration
Poor skin turgor….”tenting”
Temperature increase
Body less able to cool itself through perspiration
Urine output decreases
Symptoms of dehydration in the elderly client may be
atypical
Altered mental status
Light-headedness
Syncope
Symptoms are a result of hypovolemia causing
inadequate blood supply resulting in decreased oxygen
supply to the brain
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Fluid Imbalances:
Dehydration
Medical Treatment
Goal: replace fluids and resolve cause of dehydration
Moderate or severe dehydration:
IV therapy using fluid with same osmolarity of
blood (isotonic)
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Fluid Imbalances:
Fluid Volume Excess/Overload
Overhydration
Too much fluid in body
Most problems result from too much fluid in
bloodstream or from dilution of electrolytes and
RBC’s
Most common result of overload is
Hypervolemia… excess fluid in intravascular
space
Healthy adult kidneys can compensate for mild
to moderate hypervolemia
Increase urinary
output
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Fluid Imbalances:
Fluid Volume Excess/Overload
Causes related to excess intake of fluid or
inadequate excretion of fluid
Poorly controlled IV therapy
Excessive irrigation of wounds or body cavities
Excessive ingestion of water
Renal failure
Heart failure
Inappropriate ADH
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Fluid Imbalances:
Fluid Volume Excess/Overload
Prevention
Avoid excessive fluid intake
Monitor IV fluids carefully
Pumps or burrette
Assess patient for S/S of fluid overload
Monitor amount of fluid used for irrigations
Gastric lavage, enemas etc.
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Fluid Imbalances:
Fluid Volume Excess/Overload
Signs & Symptoms
Vitals sign changes (opposite of dehydration)
Blood pressure elevated
Pulse bounding
Respirations increased and shallow
Neck vein distention
Pitting edema esp. feet and legs
Pale, cool skin
Increased urine output, urine diluted almost like water
Rapid weight gain
Severe overload
Moist crackles, dyspnea & ascites
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Fluid Imbalances:
Fluid Volume Excess/Overload
Medical Treatment
After supporting patient’ s breathing…..goal
of treatment is to rid body of excess fluid &
resolve underlying cause of overload
Drug therapy & diet therapy are commonly
used
Positioning: semi Fowler's or high Fowler’s
Facilitate ease of breathing
Greater lung expansion aiding respiratory effort
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Fluid Imbalances:
Fluid Volume Excess/Overload
Oxygen therapy
Ensure
adequate perfusion of major organs
Minimizes dyspnea
Hx of COPD…limit to no more than 2l/min
Higher oxygen concentrations may cause patient to lose
stimulus to breathe causing respiratory arrest
Diuretics…rapidly
rid body of excess water
Lasix or furosemide is drug of choice if kidney function
is adequate
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Fluid Imbalances:
Fluid Volume Excess/Overload
Diet Therapy
Mild
to moderate fluid restriction may be used
Sodium restricted diets may be necessary
1-2 g Na+ for sever overload
Specific diet therapy depends on patient condition,
medication as well as any other medical conditions
that may exist
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ACID-BASE IMBALANCES
Most are caused by acute and chronic illness or
conditions
Primary treatment is to manage the underlying
cause…correcting imbalance
Role of nurse
Identify patients at risk
Monitor lab test values
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ACID-BASE IMBALANCES
Lab tests
ABG (arterial blood gases)
Types of imbalances
Acidosis
Alkalosis
Imbalances can be acute or chronic
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Acid-Base Balance:
ABG Analysis
pH
PaCO2
7.35 (acidic)-7.45 (alkalotic)
35 – 45 mm Hg
Less than 35-hyperventilation has occurred
Greater than 45-hypoventilation has occurred
PaO2
80 to 100 mm Hg
Less than 60-anaerobic metabolism
Normal decline in PaO2 in older adults
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Acid-Base Balance:
ABG Analysis
Oxygen saturation
Hemoglobin is saturated by oxygen
95-99%
Below 60=large drop in saturation
Base excess
+ or - 2
Bicarbonate (HCO3-)
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ACID-BASE IMBALANCES
Acidosis
pH below 7.34
Blood becomes more acidic than normal
Too much acid in body or too little base causes
acidosis
Two types
Respiratory: caused by problems in respiratory
system
Metabolic: problems in the rest of the body
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ACID-BASE IMBALANCES
Alkalosis
pH increases above 7.45
Blood becomes more alkaline than normal
Too much base in body or too little acid causes
acidosis
Two types
Respiratory: caused by problems in respiratory
system
Metabolic: problems in the rest of the body
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ACID-BASE IMBALANCES
Respiratory Acidosis
Caused primarily by respiratory problems
CO2 is not “blown off” well enough during expiration
Build up of CO2 in blood, mixes with water …creates a weak
acid in body….increasing acidity of blood
Acute acidosis
Hypoventilation
Acute flare up of chronic respiratory disease (may have
chronic resp acidosis)
Drugs (decreased respirations)
Neurological problems (decrease respirations)
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ACID-BASE IMBALANCES
Respiratory Acidosis
Signs & Symptoms
Involve CNS and MS systems
As CO2 increases, mental status is altered
Progresses from confusion & lethargy to stupor &
coma if untreated
Lungs are unable to rid body of excess CO2
Respirations become more depressed & shallow as
muscles weakness progresses
Treatment
Aggressive management of underlying problems
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2005 by Mosby, Inc.
ACID-BASE IMBALANCES
Metabolic Acidosis
Can result from too much acid in body (usually fixed acids) or
too little bicarbonate in body
Uncontrolled diabetes mellitus and end-stage renal
disease are the two main causes of too much fixed acids
GI tract is rich in bicarbonate
Diarrhea or prolonged suctioning place pt at high risk
Bicarbonate or base loss
Serum pH decreases and bicarbonate level decreases
Serum K+ increases in metabolic acidosis
Excess H+ in ECF moves into cells in exchange for K+,
which leaves the cells and enters the blood
A method of compensating for the acidotic state
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ACID-BASE IMBALANCES
Metabolic Acidosis
Signs & Symptoms
Similar to respiratory acidosis except for
respiratory pattern
Lungs rid of extra carbon dioxide through
Kussmaul’s respiration…deep & rapid, in pt
with healthy lungs
Treatment
Management of underlying disease or condition
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ACID-BASE IMBALANCES
Respiratory Alkalosis
Least common acid-base imbalance
Occurs when there is excessive loss of carbon dioxide
through hyperventilation
May occur with anxious or fearful
Have rapid shallow respirations
Light headed
May be confused
Heart rate increases and pulse becomes weak and thready
Serum pH is inceased & PaCO2 is very low
May occur as a result of high altitudes
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ACID-BASE IMBALANCES
Respiratory Alkalosis
Treatment
Have pt rebreathe own CO2
Rebreathing mask
Paper bag
Treat underlying cause
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ACID-BASE IMBALANCES
Metabolic Alkalosis
Results form excessive ingestion of bicarbonate or
other bases or loss of acids from body
Overuse of antacid or baking soda (Na
bicarbonate)
Prolonged vomiting or NG suctioning can lead to
loss of acids since stomach contains HCL
Serum pH is increased
Serum Bicarbonate
Serum Potassium decreases
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2005 by Mosby, Inc.
ACID-BASE IMBALANCES
Metabolic Alkalosis
H+ from ICF moves into blood in exchange for
K+ and K+ moves from the blood into the cells
Body attempting to keep acid-base in balance
Hypocalcemia may also accompany hypokalemia
Signs & symptoms
Related to hypokalemia and hypocalemia
Treatment
Identify and manage underlying cause
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Assessment of Risk Factors
Age
Acute illness
Chronic illness
Environmental factors
Diet
Lifestyle
Medication
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Client Assessment
Physical assessment
Intake and output
Laboratory studies
Client expectations
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Nursing Diagnoses
Decreased cardiac output
Deficient fluid volume
Excess fluid volume
Impaired mobility
Impaired skin integrity
Ineffective tissue perfusion
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Planning
Goals and outcomes
– Client will demonstrate fluid
balance by moist, mucous
membranes, balanced I&O, and
stable daily weights within 48 hours
Setting priorities
Continuity of care
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Implementation
Client education
Daily weights and I&O measurement
Enteral replacement of fluids
Restriction of fluids
Parenteral replacement of fluids and
electrolytes
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Intravenous Therapy
The primary goals of intravenous therapy (IV)
include
Achieving normal fluid and electrolyte balances
Achieving optimal nutrition status
Maintaining homeostasis through blood and blood
component administration
Treating numerous conditions with medication
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Nurse Responsibilities
Verify Physicians order
Obtain the correct solution as ordered
Collect equipment needed
Explain procedure to client
Perform venipuncture & initiate the infusion
according to agency P & P
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IV Fluids
Isotonic
Has the same effective osmolality as body fluids
Sodium chloride solution (0.9%)-normal saline
Hypertonic
Have an effective osmolality greater than body fluids
( pulls fluids into the vascular space by osmosis,
resulting in an increased vascular volume that can lead
to pulmonary edema, particularly in clients with heart
or renal failure).
10% dextrose in normal saline
3% sodium chloride
5% sodium chloride
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IV Fluids
•
Hypotonic
• Have an effective osmolality less than body
fluids
½ hypotonic saline (0.45%)
5% dextrose in 0.45% saline
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IV Medications
LPN & RN’s may hang piggyback medications
Assess patency of existing IV infusion line
before hanging piggyback medication
Check compatibility of drug with existing IV
solution before administering
Review client’s history of drug allergies
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Complications
Fluid volume excess
SOB
Crackles in the lung
Tachycardia
Circulatory overload
SOB
Cough
Elevated BP
Periorbital edema
Dependent edema
Engorged neck veins
Moist breath sounds
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2005 by Mosby, Inc.
Evaluation
Client care
Client expectations
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2005 by Mosby, Inc.