Transcript LPN-C - Faculty Sites

LPN-C
Unit Four
Rationale for Intravenous
Therapy
What is the Purpose of
Intravenous Therapy?

Maintenance
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Water
Glucose
Protein
Vitamins
Electrolytes
pH
Restoration of previous losses
 Replacement of present losses
 Administration of medication

Water
Water is necessary for adequate kidney
function –
Normal Intake
Normal Output
Oral liquids
Water in food
Metabolism
Total
1300mL
1000mL
300mL
2600mL
Urine
Stool
Lungs
Skin
Total
 Individual fluid requirements vary
1500mL
200mL
300mL
600mL
2600mL
◦ Total body water percentage is higher in infants (80%
compared to 60% in adults)
◦ Infants require more water than older children or adults
◦ Infants are more vulnerable to fluid volume deficit
Glucose
Converted to glycogen by the liver
 Has 4 main uses in parenteral therapy
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Improves hepatic function
Supplies the necessary calories for energy
Spares body protein
Minimizes ketosis
Approximately 100 – 150g of glucose is
needed daily to minimize protein
catabolism
 1 liter of 5% dextrose in water supplies 50g
of glucose
 Dextrose in water is available in 2.5%, 5%,
10%, 20%, and 30%
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Glucose (cont’d)
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Dextrose concentrations higher than 10%
must be given through a central vein
◦ The exception is 50% dextrose slow IV push at
a rate of 3mL/min through a peripheral vein for
emergency treatment of hypoglycemia
Protein

Amino acids are the building blocks of the
body
◦ Tissue growth and repair
◦ Wound healing
Available in concentrations of 3.5 – 15%
 Used in TPN centrally and peripherally
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Protein (cont’d)
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Daily requirements = 1g protein/kg body
weight
◦ Amount increases as stress to the body
increases
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Gluconeogenesis = conversion of protein to
glucose to meet energy requirements
◦ Occurs during starvation, stress, or infection
◦ Uses large amount of energy
◦ Body will use protein for energy if there are
inadequate glucose stores
Vitamins

Vitamins B and C are most frequently used
◦ Vitamin B is needed for the metabolism of
carbohydrates and maintenance of GI function
◦ Vitamin C promotes wound healing
Electrolytes
Correction of electrolyte imbalances is
important in preventing serious
complications
 Important in parenteral therapy
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◦ Potassium, sodium, chloride, magnesium,
phosphorus, calcium, bicarbonate
Electrolytes (cont’d)
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Potassium
◦ Adequate replacement therapy = 20mEq/L
◦ Patients who need potassium replacement –
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Stress from tissue injury
Wound infection
Gastric or bowel surgery
Prolonged gastric suction
◦ Assess renal function prior to potassium
replacement
 Excreted through the urine
 Intoxication can occur rapidly and with no symptoms
◦ Slow rate of infusion
 no more than 20mEq/L per hour via peripheral line
 no more than 40mEq/L per hour via central line
◦ Never give potassium via IV push
◦ Always use a cardiac monitor with K+ infusion
Electrolytes (cont’d)
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Potassium (cont’d) --
◦ Infiltration of potassium is extremely irritating
to the tissue
 Can cause necrosis
 Imperative to use extravasation protocol
 In the case of infiltration, discontinue the infusion,
apply cool compresses, and elevate the extremity by
4 inches
pH
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Most IV solutions are acidic
◦ Allows for longer shelf life
◦ The more acidic a solution, the more irritating
to the vein
Parenteral Nutrition

Peripheral venous delivery of parenteral
nutrition (PPN)
◦ Glucose concentration is not to exceed 10%
◦ Usually utilized for 3 – 7 days
◦ Assess for metabolic abnormalities
 Hyperglycemia
 Most common metabolic abnormality in PPN
 Rapid administration of fluid
 Increased levels of stress hormones
 Hypoglycemia can occur if infusion is discontinued
abruptly
 Hypokalemia
 Insulin-related shift of potassium from the extracellular
compartment to the intracellular compartment
Fluid Balance in Infants and Children
More vulnerable to fluid volume deficit
 Kidneys are immature up to 2 years of age
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◦ Cannot conserve or excrete water or sodium in
response to imbalances as efficiently as adults
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Body surface area in infants is larger than
in adults per size
◦ Lose more fluid through the skin
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Infants have a higher metabolism rate
which requires more water per size
◦ Produce more heat than adults
◦ Larger amount of metabolic waste to secrete
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Less stable regulatory responses to fluid
imbalances
Fluid Balance/Infants/Children (cont’d)
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Fevers are higher and last longer in acute
illness
◦ Increases fluid loss
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Symptoms of fluid imbalance
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Decreased appetite
Less active
More irritable
Flaccid appearance
Diarrhea, vomiting
Decrease in voiding
Nursing assessment
◦ Assess concentration of urine
Fluid Balance/Infants/Children (cont’d)
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Nursing assessment (cont’d) -◦ Weigh diapers
◦ Monitor for diarrhea
 Common cause of isotonic dehydration
 Proportionate loss of water and electrolytes
 Formula containing an inappropriately high amount
of solute can cause diarrhea that leads to hypertonic
dehydration
 Greater loss of water than electrolytes
◦ Monitor for weight changes
 Record weight before onset of illness
 Physician’s records
 Parent/family/caregiver report
 Weight loss resulting from fluid volume deficit is
more rapid than with loss of body mass
Fluid Balance/Infants/Children (cont’d)
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Nursing assessment (cont’d) –
◦ Monitor vital signs
 Blood pressure is not always reliable because
elasticity of the blood vessels in children keeps blood
pressure stable initially
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Tissue turgor
◦ Skin remains slightly raised for a few seconds
with fluid volume deficit
◦ Skin turgor begins to decrease after 3-5% body
weight is lost as fluid
◦ Obese infants/children have deceptive skin
turgor
 Normal in appearance in spite of fluid volume deficit
Fluid Balance in the Elderly
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At risk for fluid volume deficit due to
normal aging changes
◦ 6% reduction of total body water
◦ Decrease in ratio of intracellular fluid to ECF
◦ Loss of 30-50% glomeruli by the age of 70
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Decrease in glomerular filtration rate
Decreased ability to concentrate urine
Decreased secretion of aldosterone
Decrease in the response of the distal tubule to ADH
◦ Decrease in glucose tolerance
◦ Decreased sensation of thirst
◦ Decreased skin elasticity
 Poor indication of turgor
◦ Atrophy of the sweat glands
Fluid Balance in the Elderly (cont’d)
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Normal aging changes (cont’d) -◦ Diminished capillary bed
 Less effective cooling of body temperature
◦ Decreased cardiac output
 Increased risk for orthostatic hypotension
 Increased risk for falls
◦ Decreased elasticity of arteries
◦ Immediately assess fluid status with any
changes in mental status
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Typical assessment findings
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Dehydration frequently seen
Normal body temperature lower (97°F)
Mucus membranes less moist
Positional changes in blood pressure common
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Fluid Balance in the Elderly (cont’d)
Typical assessment findings (cont’d) –
◦ Most accurate assessment of skin turgor is
over the sternum
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Special problems in the elderly
◦ Hypernatremia
 Common problem in LTC facilities
 Immobility
 Unable to express thirst
◦ Reduced motility of GI tract
 Laxative dependency
◦ Heat stroke
 Elderly more susceptible
 Decreased efficacy of sweat glands
 Normal temperature decreases with age
 Temperature of 99°F would be high for the body
Fluid Balance in the Elderly (cont’d)
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Special problems (cont’d) -◦ Radiocontrast agents (IVP)
 High in sodium
 Difficulty excreting due to ↓ glomerular filtration rate
◦ Preoperative concerns
 Administration of adequate IV fluids before surgery
 Improves renal blood flow and renal function
 Minimum urine output should be 50mL/hour
 High risk for hypothermia in the operating room
 Cool fluids, cool environment, etc.
◦ Diminished respiratory function interferes with
elimination of carbon dioxide
 Leads to respiratory acidosis
 Achieve maximum ventilation through suction,
turning, activity
Fluid Balance in the Elderly (cont’d)
Special problems (cont’d) -◦ Preparation for diagnostic tests
 Bowel cleansing
 NPO status
Diet and Lifestyle Factors Affecting Fluid
Balance
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Difficulty chewing or swallowing
◦ Inadequate food/fluid intake
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Malnutrition/starvation
◦ Low protein intake; altered fluid volume status
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Excessive alcohol consumption
◦ Liver damage leading to fluid/electrolyte
imbalance
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Environmental Factors & Fluid Balance
Vigorous exercise increases metabolism,
ventilation, sweating
◦ Increases fluid demand
◦ Potential lack of fluid intake
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Heat injuries
◦ Exposure to hot, humid environments increases
sweat production to as much as 2L/hour
◦ Body fluid weight loss >7% is associated with
failure of body cooling mechanisms
Medications Altering Fluid Balance
Diuretics = excessive fluid loss
 Chemotherapy = nausea/vomiting, poor
oral intake
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Fluid Needs for Those with Acute Illness
Surgery can result in blood and fluid loss
 Gastroenteritis causes nausea/vomiting
and diarrhea
 Nasogastric suctioning leads to fluid and
electrolyte losses
 Brain injury from stroke, trauma, or tumor
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◦ Causes cerebral edema, which may put
pressure on the hypothalamus and/or pituitary
◦ Alters ADH
 SIADH
 Diabetes insipidus
 Excessive or inadequate ADH production/release
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Burns
Burns
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Factors affecting fluid loss -◦ Surface area
 The larger the burn, the greater the fluid loss
◦ Extent, depth, and cause of the burn
◦ Age of the client
◦ Pre-existing medical conditions
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Diagnostic findings –
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WBC reflects immune function
Hgb/HCT increases due to fluid loss
Glucose increases due to stress response
Sodium decreases (trapped in third spaces)
Potassium increases due to tissue destruction
Burns (cont’d)
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Third space fluid shifts -◦ Phase I → plasma to interstitial space
 Occurs rapidly (before the end of the 1 st hour)
 Plasma leaks out through damaged capillaries at the
burn area
 Edema forms
 Hypovolemia occurs (may lead to acute tubular necrosis)
 Decreased renal perfusion
 Low urine output
 Hyperkalemia
 Fluid accumulation phase occurs during the first 36
to 48 hours
 Capillaries have recovered by the end of this time
Burns (cont’d)
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Third space fluid shifts (cont’d) -◦ Phase II → fluid remobilization
 Begins approximately 48 hours after burn occurs
 Edema at burn site resolving
 Hypervolemia due to fluid shifting back into the
intravascular compartment
 Metabolic acidosis due to accumulation of acids
released from the injured tissue
 Respiratory acidosis due to inhalation injury that
interferes with gas exchange
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Nursing assessment –
◦ Rule of Nines
◦ Lund-Browder Chart
LUND-BROWDER CHART
Relative Percentage of Body Surface Area Affected by Growth
Age in years
0 1 5 10
A-head (back or front)
9½ 8½ 6½ 5½
B-1 thigh (back or front)
2¾ 3¼ 4 4¼
C-1 leg (back or front)
2½ 2½ 2¾ 3
15
4½
4½
3¼
Adult
3½
4¾
3½
Burns (cont’d)
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Treatment -◦ Aggressive fluid replacement is necessary to
prevent complications
 Need to induce urine output at 1cc/kg/hour
◦ Use large bore IV in a peripheral vein in an area
that is unaffected by burn injury
 2nd choice = central line in an unaffected area
 3rd choice = peripheral line in an affected area
 Last choice = central line in an affected area
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Monitor for IV-related sepsis
Foley catheter placement
Early burn wound excision
Timely initiation of enteral nutrition
Fluid Needs for Those with Chronic
Illness
Liver disease decreases production of
albumin, which affects the ability to
maintain vascular volume
 Renal disease limits the ability to regulate
fluid or electrolytes via urine output
 Diabetes increases the risk for
hyperglycemia and hypertonic dehydration
 Cancer treatment (chemotherapy) induces
nausea/vomiting with fluid loss and
decreased intake
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Diabetic Ketoacidosis (DKA)
Occurs in 2 – 5% of people with Type I
Diabetes Mellitus
 Most often begins with an infection
 Can also be seen in Type II Diabetes
Mellitus if illness or stress exceeds the
ability of the pancreas to secrete adequate
insulin
 Death occurs in 1 – 10% of cases even
with appropriate treatment
 Onset is sudden (less than 24 hours)
 Diagnostic criteria includes hyperglycemia,
hyperketonemia, and metabolic acidosis
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DKA (cont’d)
Pathophysiology - Body is unable to utilize carbohydrates
◦ Not enough insulin to transport glucose into the
cells
◦ Body resorts to utilizing fats for energy
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Results in ketones in the blood and urine
◦ Leads to acidosis
Etiology –
 Inadequate medication/insulin
 Infection
 Change in diet, exercise
 Other stressors
DKA (cont’d)
Clinical manifestations - Rapid, weak pulse
 Kussmaul’s respirations
 “Fruity” breath
 Nausea/vomiting, abdominal pain
 Dehydration
 Polyuria, polydipsia
 Normal/low temperature in the presence
of infection
 Weight loss
 Dry skin
 Sunken eyes, soft eyeballs
 Lethargy, coma
DKA (cont’d)
Lab findings –
 Serum glucose = >300mg/dL
 Serum ketones = positive
 Urine ketones = positive
 Serum pH = <7.35
 Serum HCO3 = <15mEq/L
 Serum potassium = ↑ with acidosis, ↓ with
dehydration
 BUN = >20mg/dL due to dehydration
 Creatinine + >1.5mg/dL due to
dehydration
DKA (cont’d)
Emergency management –
 Establish a patent airway
 Administer oxygen and NaHCO3 if ↓ pH
 Place IV with large bore catheter
 Administer NS per IV
◦ 1L/hour for first 2-3 hours to stabilize blood
pressure and ensure adequate urine output
IV fluid changed to D5 ½ NS when serum
glucose reaches 250mg/dL
 Urine output will decrease as osmotic
diuresis effect of hyperglycemia is reduced
 Careful monitoring of potassium level
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DKA (cont’d)
Ongoing monitoring –
 Monitor blood glucose
 Assess for hypokalemia
◦ Potassium will reenter the cell with insulin
administration
Will need to decrease infusion rate when
blood glucose is ≤300mg/dL
 Anticipate order of D5W when blood
glucose level is 250mg/dL
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◦ Reduces risk of hypoglycemia
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Assess for signs and symptoms of
hypoglycemia
◦ Anxiety, behavior changes, confusion,
headache, slurred speech
◦ Blurred vision, hunger, cold sweats, tachycardia
Hyperglycemic-Hyperosmolar
Nonketotic Syndrome (HHNS)
HHNS is a medical emergency with a high
mortality rate
 Hyperosmolar state caused by
hyperglycemia
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◦ Blood glucose = 800mg/dL
◦ Serum osmolarity = possibly >350mOsm/L
Exhibits no ketosis
 May be seen in Type II Diabetes Mellitus
 Often related to impaired thirst sensation
or functional inability to replace fluids
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HHNS (cont’d)
Rapid progression
◦ Hours to days
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Clinical manifestations –
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Polyuria, polydipsia, dehydration, aphasia
Altered mental status (lethargy → coma)
Postural hypotension, tachycardia
Seizures, tremors, nystagmus, hyperreflexia
Treatment –
◦ Management is similar to DKA except HHNS
requires greater fluid replacement as patient
can have a 9-12L fluid deficit
◦ Administer regular insulin at 0.1U/kg/hour
until glucose level drops to 250mg/dL
HHNS (cont’d)
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Treatment (cont’d) –
◦ Fluid resuscitation
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Administer 1-2L NS for 1st hour
Follow with 1L/hour for the next several hours
Hyperglycemia will decrease with fluid resuscitation
May need to give low-dose insulin if patient is
hyperkalemic, acidotic, or in renal failure
◦ Support airway, breathing, circulation
Differences between Diabetic Ketoacidosis
(DKA) and Hyperglycemic-Hyperosmolar
Nonketotic Syndrome (HHNS)
DKA
Onset
Serum Glucose
Serum Ketones
Serum pH
Serum HCO3
Serum K
Sudden
>300
Yes
<7.35
<15 mEq/L
Normal
↑ with acidosis
Serum Osmolarity
Variable
BUN
↑ ~ dehydration
Creatinine
↑ ~ dehydration
Urine Ketones
Positive
HHNS
Gradual
>800
No
>7.4
>20 mEq/L
Normal
↓ with dehydration
>350 mOsm/L
↑
↑
Negative
Gastrointestinal Disturbances
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The stomach is acidic
◦ pH = 1.0 – 3.5
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Fluid volume deficit possible
◦ Prolonged vomiting
◦ Gastric suction
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Monitor for hypokalemia
◦ Potassium is present in gastric juices
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Monitor for hyponatremia due to prolonged
loss of sodium
◦ Suctioning
◦ Nasogastric irrigation with plain water
Fluid Volume Deficit
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Types of fluid volume deficit –
◦ Isotonic fluid loss
◦ Hypertonic dehydration
◦ Third spacing
Isotonic Fluid Loss
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Fluid and solute are lost equally
◦ Serum osmolarity remains normal
Intracellular water is not disturbed
 Fluid loss is extracellular fluid
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◦ Can quickly lead to shock
◦ Requires extracellular fluid replacement
◦ Emphasis is on increasing vascular volume
Isotonic Fluid Loss (cont’d)
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Causes –
◦ Hemorrhage
 Loss of fluid, electrolytes, proteins, and blood cells
results in inadequate vascular volume
◦ Gastrointestinal losses
 Vomiting, NG suctioning, diarrhea, drainage from
fistulas/tubes
◦ Fever, environmental heat, diaphoresis
 Profuse sweating causes water and sodium loss
through the skin
◦ Burns
 Damages skin capillary membranes
 Allows fluid, electrolytes, and proteins to escape into
burned tissue area, leaving less vascular volume
Isotonic Fluid Loss (cont’d)
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Causes (cont’d) –
◦ Diuretics can cause excessive loss of fluid and
electrolytes
◦ Third spacing
 Fluid moves from the vascular space into
extracellular spaces
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Treatment –
◦ Expand extracellular volume with isotonic IV
fluids
 Increases circulating blood volume
 Restores renal perfusion
◦ Provide blood transfusion for hypovolemia
caused by hemorrhage
Isotonic Fluid Loss (cont’d)
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Treatment (cont’d) –
◦ Administer 1–2L bolus of isotonic fluid for
adults
 Infuse in 30 minutes or less
◦ Administer up to an additional 2–3L
 Improves urine output, blood pressure, heart rate,
and mental status
◦ Infuse 20–30 mL/kg bolus of isotonic fluid for
infants/young children to improve urine output,
heart rate, respiratory rate, and mental status
Hypertonic Dehydration

More water is lost than solute
◦ Creates a solute excess
 Primarily sodium
◦ Results in fluid volume deficit
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Solute can also be gained in excess of
water
◦ Creates a similar imbalance
◦ Most common with sodium or glucose
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Serum osmolarity becomes elevated
◦ Results in hypertonic extracellular fluid
◦ Pulls fluids into the vessels from the cells by
osmosis
◦ Causes cells to shrink and become dehydrated
Hypertonic Dehydration (cont’d)
Causes –
 Inadequate fluid intake
◦ Inability to respond to thirst
◦ May occur due to age (infants or the elderly),
immobility, nausea, anorexia, dysphagia, or
being NPO without fluid replacement
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Severe or prolonged isotonic fluid losses
◦ Extracellular fluid becomes hypertonic and
draws water from the cells
 Compensatory mechanisms become exhausted
 Conservation of water via the kidneys depleted
 Results in cellular dehydration
◦ May occur with nausea/vomiting, diarrhea
 Loss of more water than solute
Hypertonic Dehydration (cont’d)
Causes (cont’d) –
 Watery diarrhea
◦ Loss of more water than electrolytes
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Diabetes insipidus
◦ Leads to massive, uncontrolled diuresis of
dilute urine
 As much as 30L/day
 Can quickly lead to shock and death
◦ Usually caused by a brain injury
 Damages/puts pressure on the hypothalamus or
pituitary gland
◦ Need to administer parenteral vasopressin
◦ In a fluid volume deficit related to diabetes
insipidus, urine will be pale, dilute, and high in
volume
Hypertonic Dehydration (cont’d)
Causes (cont’d) –
 Increased solute intake
◦ Excessive salt, sugar, or protein intake without
a proportional intake of water
◦ Increases plasma osmolarity
◦ Water is pulled from the cells, leading to
cellular dehydration
◦ Results in osmotic diuresis, which makes
cellular dehydration worse
 Dangerous for patients with heart or kidney problems
Conditions that lead to hypertonic
dehydration –
 Highly concentrated enteral or parenteral
feedings
Hypertonic Dehydration (cont’d)
Conditions that lead to hypertonic
dehydration (cont’d) –
 Improperly prepared infant formulas that
are too concentrated
 Hyperglycemia and/or diabetic
ketoacidosis
◦ Excessive glucose and ketones in the blood

Increased sodium ingestion
◦ Ingestion of excessive amounts of seawater
◦ Taking salt water tablets
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Excessive use of osmotic diuretics
Hypertonic Dehydration (cont’d)
Clinical manifestations –
 Thirst
◦ Early sign of dehydration
◦ Unreliable in the elderly and the very young

Concentrated urine
◦ Dark in color
◦ High specific gravity (normal is 1.010 – 1.030)

Low urine volume
◦ Normal output for adults is 30mL/hour
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Dry mucus membranes
◦ When assessing mucus membranes,
remember that environmental conditions can
also cause dry lips
Hypertonic Dehydration (cont’d)
Clinical manifestations (cont’d) –
 Dry skin
◦ Decreased turgor
◦ Decreased elasticity
◦ Tenting
 Tissues stick together from interstitial fluid loss
 Unreliable in the elderly due to decreased elastin
 Test on sternum, forehead, inner thigh, top of hip instead of
arms and legs
 Check infant skin over abdomen or inner thighs
Dry tongue with longitudinal furrows
 Decreased tearing with dry conjunctiva
 Sunken eyes
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Hypertonic Dehydration (cont’d)
Clinical manifestations (cont’d) –
 Sunken or depressed fontanel in infants
less than 1 year
 Flat neck veins and poor peripheral vein
filling
◦ Jugular veins are nondistended even with the
head of bed at <45 degrees
◦ When the hand is placed lower than the heart,
the hand veins normally distend in 3 – 5
seconds
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Tachypnea
Hypertonic Dehydration (cont’d)
Clinical manifestations (cont’d) –
 Low grade fever
◦ May be higher in severe dehydration
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Mental status changes
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Often the first sign noticed in the elderly
Irritability, restlessness
Drowsiness, lethargy
Confusion
Decreased cardiac output
◦ Tachycardia (early sign in infants)
◦ Weak, thready pulse
◦ Cool extremities with delayed capillary refill
Hypertonic Dehydration (cont’d)
Clinical manifestations (cont’d) –
 Postural hypotension when rising from
lying to standing position
◦ Pulse increased by greater than 10-15 bpm
◦ Fall in systolic blood pressure by greater than
10-15 mmHg
◦ The greater the fall in blood pressure or rise in
heart rate, the greater the fluid volume deficit
◦ Weakness, dizziness, light-headedness,
syncope
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Frank hypotension
◦ Exists even when lying down
◦ Late sign in infants and young children
Hypertonic Dehydration (cont’d)
Clinical manifestations (cont’d) –
 Acute weight loss
◦ 2% body weight loss
 Mild fluid deficit (thirst)
 1 – 2 L fluid loss in an adult
◦ 5% body weight loss
 Moderate fluid deficit
 Signs and symptoms of dehydration appear
 3 – 5 L fluid loss in an adult
◦ 8% body weight loss
 Severe fluid deficit
 Frank hypotension
 5 – 10 L fluid loss in an adult
◦ >15% body weight loss
 Fatal
 >10L fluid loss in an adult
Hypertonic Dehydration (cont’d)
Parenteral therapy –
 Hypovolemia and impending shock
◦ Isotonic fluids administered for adequate
circulation and renal perfusion
◦ Hypotonic solutions administered to correct
cellular dehydration
 Given slowly to prevent cerebral edema due to
sensitivity of brain cells to hypotonicity
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Hypervolemia
◦ Resulting from excessive sodium intake
◦ Administer a diuretic with hypotonic fluid to
provide free water to cells while preventing
vascular volume overload
Hypertonic Dehydration (cont’d)
Nursing interventions - Monitor vital signs for changes in heart
rate, blood pressure, and respiratory rate
 Assess mental status
◦ Lack of improvement (or worsening) could
indicate the infusion of hypotonic fluids is too
rapid
Monitor urine output and concentration
 Monitor IV rate

◦ Watch for fluid volume overload
Monitor I&O
 Monitor weight daily
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Hypertonic Dehydration (cont’d)
Lab findings –
 Hemoconcentration
◦ Plasma becomes concentrated to the red blood
cells and urea particles
◦ BUN would be high

High urine specific gravity (>1.030)
◦ Kidneys conserve water while continuing to
excrete solute
◦ In cases of diabetes insipidus, specific gravity
would be low (<1.010)

Increased plasma concentration
◦ Elevated serum osmolality (>300mOsm/kg)
◦ Elevated serum potassium (>150mEq/L)
◦ Elevated serum glucose (>120mg/dL)
Third Spacing
Third spaces are extracellular body spaces
where fluid can accumulate
 This accumulated fluid is useless to the
body

◦ Unavailable for use as reserve fluid
◦ Unable to transport nutrients

Common locations for third space fluid to
accumulate –
◦
◦
◦
◦
Tissue spaces (edema)
Abdomen (ascites)
Pleural spaces (pleural effusion)
Pericardial space (pericardial effusion)
Third Spacing (cont’d)
Causes –
 Injury or inflammation
◦ Increased capillary permeability allows fluid,
electrolytes, and proteins to leak from the
vessels







Massive trauma
Crush injuries
Burns
Sepsis
Cancer
Intestinal obstruction
Abdominal surgery
Third Spacing (cont’d)
Causes (cont’d) –
 Malnutrition or liver dysfunction
◦ Prevents liver from producing albumin, which
lowers capillary oncotic pressure
 Starvation
 Cirrhosis
 Chronic alcoholism

High vascular hydrostatic pressure
◦ Pushes abnormal volumes of fluid from the
vessels
 Heart failure
 Renal failure
 Other vascular fluid overload
Third Spacing (cont’d)
Treatment –
 Osmotic diuretics are used to mobilize
some of the fluid back into the blood
vessels for elimination by the kidneys
Fluid Volume Excess

Types of fluid volume excess –
◦ Isotonic fluid excess
 Hypervolemia
 Edema
◦ Hypotonic fluid excess
 Water intoxication

Risk factors that predispose individuals to
fluid volume excess -◦ Individuals of certain age
 Elderly (due to ↓ heart and kidney function)
 Children < age 2 (due to immature kidneys)
 Children ages 2 – 12 years (due to unstable
regulatory responses)

Fluid Volume Excess (cont’d)
Risk factors (cont’d) –
◦ Acute illness
 Stimulates the stress response, which releases
cortisol, ADH, and aldosterone → promotes water
and sodium retention
◦ Chronic illness
 Cardiovascular disease causes sodium and water
retention
 Reduces the pumping strength of the heart
 Reduces blood flow to the kidneys
 Renal disease leads to abnormal retention of water,
sodium, and potassium
◦ Medications
 Long-term glucocorticoid therapy
 Drugs that act to retain sodium and fluids

Fluid Volume Excess (cont’d)
Risk factors (cont’d) –
◦ Patients receiving IV fluids
Lab findings –
 Decreased hematocrit and BUN due to
hemodilution
◦ Returns to normal once excess fluid is removed
Serum osmolarity is low
 Serum sodium is very low
 Chest x-ray may show pleural effusion
 Low PO2 and PCO2
 Decreased pH due to respiratory acidosis
(results from pulmonary edema)

Fluid Volume Excess (cont’d)

Clinical manifestations –
◦ Peripheral edema
 Legs, ankles, feet, and hands in ambulatory
individuals
 Sacrum and back in bedridden clients
◦ Edema in the legs and feet
 Indicates local obstruction of veins
 Edematous skin is often tight and shiny due to
decreased circulation in swollen tissue
◦ Puffiness in the face and around the eyes
(periorbital edema)
 Associated with heart or kidney problems
◦ Tense or bulging fontanels in children less than
1 year of age
Fluid Volume Excess (cont’d)

Clinical manifestations (cont’d) –
◦ Pitting edema
◦ High central venous pressure
 Distended neck veins when HOB is elevated
 Delayed hand vein emptying when hand is raised
above the heart for 3 – 5 seconds
◦ Venous congestion
 Hepatomegaly
 Splenomegaly
◦ Decreased urine output if cardiac or renal
function is impaired
◦ Weight gain of 3lbs over 2 – 5 days
◦ Full/bounding pulse, warm extremities

Fluid Volume Excess (cont’d)
Treatment –
◦
◦
◦
◦
◦
◦
◦
◦
◦
◦
◦
Restrict fluid intake to 1,000 – 1,500mL/day
Maintain sodium restriction
Maintain IV access
Administer diuretics
Increase protein intake to increase capillary
oncotic pressure to pull fluid out of the tissues
Monitor respiratory status
Monitor venous engorgement
Monitor I&O, daily weight
Assess for edema
Assess neurologic status
Monitor labs (BUN, HCT, sodium, ABGs, K+)
Isotonic Fluid Excess

Hypervolemia = gain of fluid and solute
(sodium) in proportional amounts
◦ Overall gain in the extracellular fluid without a
change in serum osmolarity
Edema = excess tissue (interstitial) fluid
throughout the body or specific to a body
tissue or organ
 Causes -
◦ Renal failure
 Decreased excretion of water and sodium
◦ Rapid infusion of isotonic fluid
 Exceeds the ability to compensate by the heart and
kidneys
Isotonic Fluid Excess (cont’d)

Causes (cont’d) –
◦ Heart failure
 Venous congestion
 Decreased renal blood flow leading to decreased
renal excretion of fluid and sodium
◦ High corticosteroid levels, which results in
sodium and water retention
 Therapy
 Stress response
◦ High aldosterone levels, which results in
sodium and water retention
 Stress response
 Adrenal dysfunction
Hypotonic Fluid Excess

Gain of more fluid than solute (sodium)
◦ Creates fluid volume excess
◦ Results in a deficit of sodium
◦ Serum osmolarity decreases
 Causes hypotonic extracellular fluid that gets pulled
into the cells
 Cells swell, and cerebral edema occurs

Causes –
◦ Frequent use of plain water enemas
◦ Multiple nasogastric tube or bladder irrigations
with plain water
◦ Infusing hypotonic solutions too rapidly
◦ Use of improperly prepared infant formula
Hypotonic Fluid Excess (cont’d)

Causes (cont’d) –
◦ Increased release of ADH
 SIADH causes the kidneys to retain large amounts of
water without retaining sodium
 Creates hypotonic extracellular fluid, which is drawn into the
cells
 Highly concentrated urine with low urine volume




Stress
Surgery, anesthesia
Opioid analgesics, pain
Tumors of the lung or brain
◦ Psychogenic polydipsia
 Compulsive drinking of excessive amounts of water
associated with psychiatric disorders (i.e. some types
of schizophrenia)
Hypotonic Fluid Excess (cont’d)

Causes (cont’d) –
◦ Severe or prolonged isotonic fluid volume
excess
 Compensated by increased urine output
 Clients with heart failure, renal failure, and diabetes
are sensitive to excess fluid administration
Capillary Fluid Movement

Hydrostatic pressure = the pushing force of
a fluid against the walls of the space it
occupies
◦ Generated by the heart’s pumping action
◦ Varies within the vascular system
Capillary Fluid Movement (cont’d)

Oncotic pressure = the pulling force
exerted by colloids in a solution
◦ Albumin is a pulling force for water
 Maintains normal serum oncotic pressure
 Maintains adequate vascular fluid volume
Causes of low capillary oncotic pressure -◦ Injury or inflammation (trauma, burns, sepsis)
 Increases capillary permeability
 Allows fluids and proteins to leak from the vessels
◦ Malnutrition or liver dysfunction (starvation,
cirrhosis, chronic alcoholism)
 Prevents liver from producing albumin
 ↓ capillary oncotic pressure; fluid remains in vessels
Capillary Fluid Movement (cont’d)

Starling’s Law
◦ Filtration = movement of fluid into or out of the
capillary, determined by the pushing and
pulling forces
◦ At the arterial end of the capillary, capillary
hydrostatic pressure exceeds capillary oncotic
pressure
 Fluid movement is from the capillary into the tissue
 Carries nutrients to the tissues
◦ At the venous end of the capillary, capillary
hydrostatic pressure is less than capillary
oncotic pressure
 Fluid movement is into the capillary from the tissue
 Carries wastes away from the tissues
Edema

Edema = soft tissue swelling due to
expansion of the interstitial volume
◦ Can be localized or generalized
◦ Fluid moves from the capillaries into the
interstitial space and back again, carrying
wastes with it

Increased capillary hydrostatic pressure
◦ Forces more fluid out of the arterial end of the
capillary
◦ Draws less fluid back into the venous end of
the capillary
◦ Results in edema as fluid accumulates in the
tissues
Edema (cont’d)

Decreased capillary oncotic pressure
◦ Disrupts normal movement of fluid into and out
of the capillaries
◦ Weaker pulling pressure allows more fluid to be
pushed out of the arterial end of the capillary
◦ Unable to draw adequate amount of fluid back
into the venous end of the capillary
◦ Results in edema

Causes
◦ Hypertension
◦ Hypervolemia, lymphedema
◦ Renal failure
Edema (cont’d)

Lymphedema occurs when a blockage in
the lymphatic system prevents lymph fluid
from draining adequately; as the fluid
accumulates, swelling continues
◦ Lymphatic obstruction
◦ Surgical removal of lymph nodes
Edema (cont’d)

Renal failure causes decreased renal
perfusion leading to excess aldosterone in
the blood
◦ Causes water retention that elevates the blood
pressure
◦ Increases hydrostatic pressure within the
capillaries, which forces more fluid into the
tissues
◦ Results in edema
Congestive Heart Failure (CHF)
Inability of the heart to pump enough
blood to meet the metabolic needs of the
tissues of the body
 Associated with hypertension, myocardial
infarction (MI), valvular disease
 Left ventricular failure seen with
pulmonary edema
 Right ventricular failure seen with edema
in the lower extremities
 Failure tends to occur in both ventricles, so
client will present with both peripheral and
pulmonary edema


CHF (cont’d)
Fluid and electrolyte imbalances seen with
CHF –
◦ Fluid volume excess
 Decreased renal blood flow associated with
decreased cardiac output
◦ Hyponatremia
 ADH causes greater retention of water, diluting serum
sodium level
◦ Hypokalemia
 Caused by diuretics, vomiting, and diarrhea
◦ Respiratory acidosis
 Pulmonary congestion interferes with carbon dioxide
elimination from the lungs
◦ Metabolic acidosis
 Anoxic tissue releases lactic acid

CHF (cont’d)
Fluid and electrolyte imbalances (cont’d) -◦ Edema
 Shift of intravascular fluid into interstitial tissue due
to increase in hydrostatic pressure from excessive
venous blood volume

Signs and symptoms –
◦ Fatigue due to decreased cardiac output
◦ Dyspnea
 Cardiac output is inadequate to provide for body’s
oxygen requirements
 Paroxysmal nocturnal dyspnea occurs when client is
in a recumbent position because edema fluid from
the extremities returns to the bloodstream,
increasing cardiac preload
◦ Decreased urine output due to secretion of
aldosterone and ADH

CHF (cont’d)
Signs and symptoms (cont’d) –
◦
◦
◦
◦
Cough
Tachycardia
Peripheral edema
Pulmonary edema
 Increased pulmonary venous pressure forces serum
and blood cells in the alveoli
 Severe dyspnea, coughing, pink frothy sputum
◦ Distention of the peripheral veins from elevated
venous pressure
 Visible in the hands, face, and neck
◦ Orthopnea
 Increased interstitial edema increases the work of
breathing
 Upright position fosters air exchange

CHF (cont’d)
Signs and symptoms (cont’d) –
◦ Nocturia
 Oxygen demand reduced at night, decreasing renal
constriction and increasing glomerular filtration rate
◦ Cardiomegaly
 Hypertrophy of the myocardium that helps to
maintain stroke volume

Nursing interventions –
◦ Lessen cardiac preload and afterload
 Give diuretics per IV
◦ Administer ACE inhibitors (arterial vasodilators)
◦ Restrict fluids
◦ Monitor I&O
Pulmonary Edema

Pulmonary edema is a medical emergency
◦ Place patient in high Fowler’s position
◦ Administer oxygen
◦ Administer IV morphine
 Reduces preload through peripheral dilation
 Reduces afterload through decreased blood pressure
 Reduces anxiety

Signs and symptoms –
◦ Tachypnea, dyspnea, labored breathing, cough,
moist rales, decreased oxygen saturation
◦ Third spacing as fluids are forced out of the
vessels and into spaces that normally do not
contain much fluid (ascites, pleural effusion)
◦ Acute, rapid weight gain
Basic Classifications of Infusates
Crystalloids
2. Colloids
3. Hydrating solutions
4. Hypertonic-hyperosmolar preparations
5. Blood or blood components
Crystalloids - Capable of crystallization
 Forms a solution
 Can diffuse through membranes
 Includes electrolyte solutions that may be
isotonic, hypotonic, and hypertonic
1.
Classifications of Infusates (cont’d)
Colloids –
 Cannot form a solution (does not dissolve)
 Cloudy in appearance
 Raises osmotic pressure
 Plasma or volume expander
 Types of colloids -◦
◦
◦
◦
◦
Albumin
Dextran
Plasmanate
Hetastarch
Artificial blood substitute
Classifications of Infusates (cont’d)
Hydrating Solutions (cont’d) –
 Supplements calorie intake
 Supplies nutrients
 Provides free water
◦ Maintenance
◦ Rehydration


Promotes effective renal output
Frequently used hydrating solutions
◦
◦
◦
◦
◦
Dextrose 2½% in 0.45% saline
Dextrose 5% in water (D5W)
Dextrose 5% in 0.45% saline
Dextrose 5% in 0.2% saline
Sodium chloride 0.45%
Classifications of Infusates (cont’d)
Hydrating Solutions (cont’d) –
 Electrolytes in IV solutions are measured in
mEq/L
 Milliequivalents measure how many
chemically active ions are present in a
solution
 Sodium chloride contains 154 mEq/L of
sodium and 154 mEq/L of chloride, which
equals 308 mOsm/L
 0.45% NaCl (1/2 strength saline) has 77
mEq/L of sodium and 77 mEq/L of
chloride, which equals 154 mOsm/L
Classifications of Infusates (cont’d)
Dextrose Solutions –
 Manufactured as a percentage of the
concentration in water or sodium chloride
 Expressed as the number of grams of
solute per 100mL of solvent
 5% dextrose in water solution contains 5g
of dextrose in 100mL of water
Isotonic Infusions

D5W
◦ Osmolarity = 252.52 mOsm/L
◦ Best solution for hydration
 Isotonic in bag
 Hypotonic once dextrose metabolized
◦ Does not contain electrolytes
◦ Not given to patient with increased intracranial
pressure
◦ ADH secretion is increased as a stress
response to surgery
 Use cautiously in early post-operative period to
prevent water intoxication
◦ Hypokalemia can occur due to cellular use of
glucose
 Potassium shifts from the extracellular fluid to the
intracellular fluid
Isotonic Infusions (cont’d)

D5W (cont’d) --
◦ Use cautiously in patients with signs of fluid
overload and congestive heart failure
 Dehydration with rapid infusion due to osmotic
diuresis
◦ May alter insulin/oral hypoglycemic needs in
diabetics
 Contraindicated in diabetic coma
◦ Should not be used in patients with allergies to
corn and corn products
◦ Medication incompatibilities –
Ampicillin
Diazepam
Erythromycin
Fat emulsions
Phenytoin sodium
Procainamide
Sodium bicarbonate
Warfarin sodium
Whole blood
Vitamin B12
Isotonic Infusions (cont’d)

0.9% normal saline (NS)
◦
◦
◦
◦
◦
Osmolarity = 308 mOsm/L
Only infusate compatible with a blood infusion
Maintains patency of heparin locks
Used as a diluent for medications
Replaces extracellular fluid losses by
expanding intravascular space
◦ Corrects hyponatremia
◦ Used to treat hypovolemia
◦ Can cause intravascular overload
 Monitor I&O
◦ Can cause hypokalemia
 Saline promotes potassium excretion
Isotonic Infusions (cont’d)

NS (cont’d) –
◦ Can cause hypernatremia
 Sodium may be retained in intraoperative and early
post-operative situations
 Excessive sodium retention when used with
glucocorticoids
 Contraindicated in patients with edema and sodium
retention
◦ Does not provide free water or calories
◦ Used with caution in certain patients
 Decreased renal function
 Altered circulatory function
 Elderly
Isotonic Infusions (cont’d)

NS (cont’d) –
◦ Medication incompatibilities –
Amphotericin B (antifungal)
Chlordiazepoxide HCl (Librium)
Diazepam
Fat emulsions
Levarterenol (norepinephrine)
Mannitol
Methylprednisolone sodium succinate
(Solu-Medrol)
Phenytoin sodium
IV Fluid Reminders

The body is in a state of homeostasis when
the serum osmolarity is the same as other
body fluids
◦ Approximately 280 – 300 mOsm/L

To change the osmolarity, glucose and/or
electrolytes must be added to the solvent
◦ Increases the total number of particles in the
solution
◦ Increases osmotic pressure