Transcript Fluid and Electrolytes

Fluid and Electrolytes
Presented by Joanna Shedd, MS, CNS, RN
Physiology of Fluid Balance
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Intracellular Fluid
(ICF) – inside
cells
Interstitial fluid –
tissue spaces
Plasma volume –
intravascular fluid
Physiology of Fluid Balance
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Extracellular fluid
(ECF)
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Interstitial fluid
Plasma volume
Osmolality
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# dissolved particles or
solutes in 1kg (1L) of
water
Sodium – greatest
contributor, most
common
Glucose
Urea
Tonicity
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Ability of a solution to cause a change in water
movement cross a membrane
Relative concentration of IV fluids
Tonicity
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Normal plasma
considered isotonic
Hypertonic – greater
concentration of solutes
than plasma
Hypotonic – lesser
concentration of solutes
than plasma
Osmosis
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Water movement
form area of low
solute concentration
to area of high
solute concentration
Osmosis
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Hypertonic IV – plasma
gains more solutes than
interstitial fluid  water
from interstitial fluid and
cells to plasma
Hypotonic IV – water
moves from interstitial
fluid and plasma to cells
Isotonic IV – no net fluid
shift
Fluid balance
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Water essential to
maintain fluid balance
Can go without food
longer than water
Water travels from
less concentration to
higher concentration
(osmosis)
Intake
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Drinking fluids
Ingesting foods with
moisture
Absorbing water
during metabolic
processes
Output
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Kidneys as urine
Perspiration/ sweat
Expired air (vapor)
Feces/ stool
Tears/ saliva
Thirst Mechanism
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Osmoreceptors in
hypothalamus
Hypertonic ECF
Saliva secretion decreased,
feeling of thirst
Once water absorbed, thirst
center no longer stimulated
Fluid output regulation
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Renin-angiotensin
system (RAAS) –
aldosterone
Antidiuretic hormone
(ADH) – acts on distal
renal tubule to increase
water resorption
Excess Fluid Deficit
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Dehydration
Hypovolemic shock
Treatment: IV fluid
replacement
Correct cause of disorder
Overhydration
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Volume excess
Hypervolemia
Correct cause of
disorder
Colloids
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Proteins/ large
molecules that remain in
blood for a long time
Draw water from cells
into plasma
Increase plasma
osmolality and osmotic
pressure
Colloids: uses
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Hypovolemic shock
due to burns
Hemorrhage
Surgery loss of fluid
Crystalloids
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Electrolytes used to
replace lost fluids
Promote urine output
Quick diffusion across
membranes
Leave plasma and enter
interstitital fluid
Crystalloids: uses
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Replace electrolytes
Increase total fluid
volume in body
Compartment which is
most expanded
dependent on solute
Parenteral Solutions – Isotonic
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Equal concentration of
solutes
Replace extracellular
fluid loss
No movement into or
out of ICF
Isotonic - uses
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Before and after blood transfusion
(NS)
Treat metabolic alkalosis
Intravascular dehydration
Isotonic – precautions
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Circulatory overload
Dilute concentration of
Hgb and Hct
Hyper- vs. Hypotonic
http://youtu.be/SSS3EtKAzYc
YouTube explanation of hypertonicity and
hypotonicity
Hypertonic Solutions
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Water moves from
within cell to
extracellular
compartment
Cells will shrink/
become smaller in size
Fluid shifts out of ICF
and into intravascular
Hypertonic – uses
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Intravascular dehydration/ interstitial
overload
Decreases cellular edema  raise BP and
increase UO
Draw fluid out of edematous cells to plasma
Replace electrolytes
Fluid shifted to plasma to be excreted by
kidneys
Hypertonic – precautions
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Circulatory overload
Irritation to vein walls
Careful with elderly as
water retained as a
response to stress
Hypotonic Solutions
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Concentrated salt in
intracellular (in cell)
spaces - dehydrated
Water moves into cell
Cause cells to swell,
possibly burst
Fluid shifts out of
intravascular spaces into
ICF
Hypotonic – uses
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Cellular dehydration
Hydrate cells and lower serum
sodium levels
Replace electrolytes depleted by
diuretics
Assists with renal function
Provides free water, Na, and Cl
Assists with daily body fluid needs
Hypotonic – precautions
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Depletion of
circulatory system
Nursing Management
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Assess
Infiltration – solution
enters tissue
Thrombosis – blood
clot
Thrombophlebitis –
formation of blood
clot with inflammation
Pain at administration
site
Nursing Management
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Necrosis – tissue death,
sloughing of tissue
Pulmonary edema –
overload of fluids
Air emboli – air into the
circulatory system
Nursing Interventions
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Maintain even flow at
rate ordered
Connections secure
Solution bag higher than
site
Avoid areas of flexion
Prevent
thrombophlebitis
Nursing Interventions
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Restart any infiltrated
IVs
Hospital protocol for
extravasation
Never try to “move” a
blood clot
Monitor I&Os
Monitor labwork
Nursing Education
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Need for IV therapy
Inform MD of labwork
Educate family re: pain, infiltration, do
not play with IV machinery
Care of IV line with ambulation, getting
out of bed
Assessment of patient qshift and prn
Electrolytes – Sodium
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Major electrolyte in
extracellular fluid
Regulated by sodium
consumption in diet
Excretion via kidneys
Controls body water
Sodium
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Electrophysiology of
nerves, muscles,
gland cells
Regulates pH and
isotonicity
Combines readily with
Cl and HCO3 to
promote acid-base
balance
Hyponatremia
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Induced by excessive
sweating, only water is
replaced
Examples: adrenal
insufficiency, GI
suctioning, potent
diuretics, surgery
Hyponatremia Signs/symptoms (s/s)
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Lethargy
Hypotension
Stomach cramps
Vomiting
Diarrhea
Possible seizures
Hyponatremia –
Treatment (Tx)
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Normal saline
infusion (0.9% NS)
Ringer’s Lactate
Hypernatremia
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Excessive use of saline
infusions
Inadequate water
consumption
Examples: taking drugs
such as cortisone preps
and cough medications
Excess fluid loss without
a loss of sodium
Hypernatremia – s/s
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Edema
Hypertonicity
Red, flushed skin
Dry, sticky membranes
Increased thirst
Elevated temp
Decrease/ absence of
urine
Hypernatremia – Tx
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Reduce salt intake
D5W to promote
diuresis by increasing
excretion of both salt
and water from blood
Potassium
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Major electrolyte in
intracellular fluid
Potassium
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Roles
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Muscle contraction
Conduction of nerve
impulses
Enzyme actions – CHO to
energy
Enzyme actions – amino
acids to proteins
Cell membrane function
Hypokalemia
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Potassium poorly
stored in body
Chronic administration
of IV fluids without K+
Diuretic therapy
Reduced dietary
intake
Hypokalemia
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Poor absorption – steatorrhea
Vomiting/ diarrhea
GI suctioning or drainage
Extensive burns
Hypokalemia – s/s
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N/V
Dysrhythmias
Abdominal distention
Soft, flabby muscles
Hypokalemia – Tx
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Replace orally or
parenterally
Watch for s/s
hyperkalemia
Labwork
Hyperkalemia
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Acute/ chronic renal
failure
Overtreatment with K+
salts
Metabolic acidosis
(diabetes)
Hyperkalemia – s/s
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Tachycardia followed by
bradycardia
Can lead to cardiac arrest –
v. fib
Numbness/ tingling to
extremities
Oliguria
Abdominal cramps
Weakness – decr.
neuromuscular function
Hyperkalemia – Tx
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Stop K-sparing drugs or
supplements
Hypertonic dextrose with
insulin (shift K into the
cells temporarily)
Kayexalate
Diuretic therapy
Body pH
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pH: degree of acidity or
alkalinity -7.0
less than 7.0 – acidic
greater than 7.0 – alkaline
Buffers
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Chemicals that help
maintain normal body
pH
Bicarbonate
Phosphate
Removal of Acids
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Lungs via exhalation
Kidneys via excretion
Acidosis – pH < 7.35
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Range: 7.35-7.45
Can be respiratory or
metabolic
Sleepiness/ coma
Disorientation
Dizziness/ headache
Seizures
Nursing
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Correct cause
Re-assess diagnostic
testing after intervention
Watch for s/s of alkalosis
Contraindications to HCO3
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Excess vomiting
Continuous GI suctioning
Diuretic therapy causing
hypochloremia
Hypocalcemia
Patients on low sodium diet
– sodium mixed with
bicarbonate
Benefits of NaHCO3
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Tx overdosing of acidic meds
(ASA and phenobarbital)
Alkalinization of urine  less
acid reabsorbed  increased
excretion in urine
Neutralizes gastric acid (baking
soda)
May lead to systemic alkalosis
with prolonged use
Alkalosis – pH>7.45
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Range: 7.35-7.45
Irritability
Confusion
Cyanosis
Slow respirations
Irregular pulse
Muscle twitching
Treatment
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NS with potassium –
mild
Ammonium chloride severe
Increases excretion of
bicarbonate ion
Nursing
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Correct underlying
cause
Monitor chemistry labs
Assess for s/s acidosis
Ammonium chloride
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Given to prevent lifethreatening alkalosis
s/s toxicity: pallor, sweating,
irregular breathing,
bradycardia, twitching,
convulsions
Drug irritating to vein – assess
site