Fluids and Electrolytes Balance
Josierina Y. Sarmiento, M.D.
Nephrologists
Asian Hospital and Medical Center
Body Fluids
Man have 60%
Woman have 50%
Fat contains little water
% of body weight that is water decreases
with age
Body Fluid Compartment
Intracellular Fluids
(ICF)
Extracellular Fluids
(ECF)
¾
¼
Extracellular Fluids
(ECF)
Supplies the food, oxygen, water, vitamins
and electrolytes and takes away body waste.
Fluid Spacing
First spacing – normal amount of fluids in
both the extracellular and intracellular
compartments.
Second spacing – an excess accumulation of
intestinal fluid (edema).
Third spacing – fluid accumulation in areas
that normal have no fluids or minimal
amount of fluids. (Ascites)
Electrolytes
Solutes and substances that are dissolved
in body fluids.
A. Electrolytes
B. Non – electrolytes
Compounds that do not separate into
charged particles when dissolved in
water……GLUCOSE
Electrolytes
Electrolytes are compounds that do not
separate into charged particles called ions.
Cations – positively charged ions such as
Na+.
Anions – negatively charged ions such as
Cl-.
Electrolytes
Electrolytes are found inside and outside of
the cell.
ECF
ICF
Na+
Cl–
HCO3–
K+
SO4+
PO4+
Normal Fluid Intake
and Losses in Adults
Intake
Water in food = 1000 ml
Output
Skin = 500 ml
Lungs 350 cc
Insensible
losses
Water for oxidation = 300 Feces = 150 cc
Water as liquid = 1200 ml Kidneys = 1500 cc
2500
Fluid and Electrolyte Exchange
Diffusion
Molecules and ions flow through a semi
permeable membrane from an area of
higher concentration to an area of lower
concentration.
Osmosis
Movement of water through a semi
permeable membrane from a weaker
solution to the more concentrated solution
The in intent is to equalize the strength of
solution.
Osmotic Pressure
Osmotic pressure – is the pulling of water in
the process of osmosis.
Osmolarity – an indication of whether a
person is adequately hydrated, over by
drated or dehydrated.
Normal: 275 – 295 mOsm/kg
Osmotic Movement of Fluids
Isotonic – fluids that have the same
osmolarity as the fluid inside the cell.
Example: Plain LR and plain NSS
Has the same concentration as inside the
cells
Hypotonic / Hypoosmolar
Hypotonic – fluids that contain more water
than the intercellular fluids.
Example: ½ NSS
Hypotonic fluid surrounds the cells and
causes the water to move inside the cell
until it burns.
Hypertonic Solution
Hypertonic solutions – are fluids that contain
less water (more concentrated) than
intracellular fluids.
Hypertonic solution around the cells
draws water from the cell until it shrinks.
Hypotonic Solution
Water
½ NSS
Burst
Hypertonic Solution
3% NaCl
Shrinks
Hydrostatic Pressure
Hydrostatic Pressure – is the force exerted
by fluids against the wall of it containers.
Hydrostatic Pressure – is the major force in
the movement of water out of the
capillaries.
Oncotic Pressure
Oncotic pressure – is also known as colloidal
osmotic pressure that is the presence
caused by colloids in the solution.
Colloids – are particles that are too large to
pair through a semi permeable membrane.
Example: protein
Capillary Fluid Movement
The amount and direction of fluid movement
is based on the hydrostatic pressure and
oncotic pressure.
Capillaries
Venous
End
Hydrostatic
Pressure
Oncotic
Pressure
Arterial
End
Fluid Shift
Edema – imbalance between hydrostatic and
oncotic pressure.
 Hydrostatic pressure
• CHF, tourniquet
 Oncotic pressure
• Malnutrition
• Nephrotic syndrome
Regulation of Fluids and
Electrolytes
Hypothalamus – the thirst mechanism that
stimulates us to drive. It is stimulated by
increased in serum osmolality.
Hormones:
ADH (antidiuretic hormone) – acts on the
renal tubules to retain water and decrease
urinal outputs
Aldosterone – increases sodium and
water reabsorption.
Fluids and Electrolytes
Imbalances
Hypovolemia – decreased in intravascular
fluid volume.
Occurs when water and electrolytes are
lost or unavailable to circulation.
Diarrhea, massive bleeding, excessive
sweating (marathon, runners), vomiting.
Assessment of Hypovolemia
Decreased
body
temperature
Low blood pressure
Tachycardia
Weak pulse
Increased
respiration
Weakness
Weight loss
Decreased
urine
output
Increased Hab/Hct
Treatment of Hypovolemia
Fluids
Hypervolemia
Hypervolemia is the excess of water and
electrolytes in the ECF.
Renal failure
Congestive heart failure
Assessment of Hypervolemia
Acute weight gain
Cardiac
enlargement,
cyanosis
Decreased
Hct,
Hab, RBC’s
Skin
warm
and
moise
Pitting edema
Puffy eyelids
Bounding pulse
Dyspnea, increased
respiratory rate
Distended neck vein
Treatment for Hypervolemia
Sodium restriction
Limit fluid intake
Diuretics
Electrolyte Balance
Each electrolyte has its very own function.
Too much or too little may alter the function.
Electrolytes concentration may be altered by
changing the quantity of the electrolyte or
by altering the quantity of water in the ECF
in which electrolytes is found.
Sodium
Sodium is the chief cat ion in the ECF.
NV = 135 – 145 mEq/L
Sodium function include transmission of
nerve impulses, maintain acid-base balance,
regulate water reabsorption and excretion in
kidney tubules.
Sodium
Normal Na intakes is 2 to 4 grams
Hypernatremia – too much Na in the
intravascular space; cause cell to shrink
Hyponatremia – too little Na in the
intravascular space, cause the cell to swell.
Aldosterone – reabsorbs Na in the kidney
tubules
Defining Characteristics of
Hyponatremia
Serum Na < 135 mEq/L
 Serum osmolality
Anorexia and nausea
Lethargy
Confusion, seizures, coma
Muscle twitching
Nursing Intervention for
Hyponatremia
Encourage diet high sodium
Weigh daily
Monitor neurological status
Monitor serum Na levels
Maintain free water intake
Food High in Sodium
Potato chips
Bacon / catsup
Table salt
Crackers
Cheese
Pretzels, etc.
Luncheon meat
Hypernatremia
Serum Na greater than 145 mEq/L
Due to water deficit
Serum osmolality > 295 mOsm/kg.
Defining Characteristic of
Hypernatremia
Dry tongue
Thirst
Fever
Oliguria
CNS symptoms including focal or grand mal
seizures
Nursing Intervention for
Hypernatremia
Encourage low Na diet
Accurate I;O
Hypotonic fluids
Observe for seizure
Chloride
Chloride is the major extracellular anion
Part of hydrochloric acid in the stomach
When Na is reabsorbed so is Cl
Potassium
Potassium is the major intracellular cat
ion.
Function:
1. ICF balance
2. Maintain regular heart rhythm
3. Conducts neuromuscular impulses
4. Regulation of acid-base balance
Normal potassium range: 3.5 – 5.0 mEq/L
Reasons for Hypokalemia
Diarrhea
Ostomies
Loop diuretics
Poor intake of K rich foods
Stress
Defining Characteristics
Hypokalemia
Serum K+ level less than 3.5 mEq/L
Muscle weakness
Cardiac arrhythmias
Increased sensitivity to digitalis toxicity
Muscle weakness
Fatigue
ECG changes: ST depression / U wave
Nursing Intervention for
Hypokalemia
Encourage high K foods
Monitor EKG results
IV/oral Potassium replacement
Foods high in Potassium
All dried fruits/banana
Spinach
Beef
Chocolate
Potato’s
Tomato’s
Hyperkalemia
Renal insufficiency.
High potassium intake.
Shift of potassium out of the cell as in
acidosis.
Defining Characteristics of
Hyperkalemia
Potassium levels greater than 5.0 mEq/L
Neuromuscular weakness
EKG changes – peaked T waves widened
QRS complex
Flaccid muscles paralysis
Heart block
Nursing Intervention for
Hyperkalemia
Monitor EKG changes
Administer calcium solutions to neutralize
the potassium
Monitor muscle tone
Give kayexalate
Glucose + insulin solution
Diuretics
Calcium
For transmission for nerve impulses
For muscle contraction
Blood clotting
Bone and tooth formation
Normal level: 8.6 – 10.6 mg/dl
2 hormones:
1. Parathormone
2. Calcitonin
Reasons for Hypocalcemia
Vitamin D deficiency
Malabsorption
Excessive GI loss
hypoparathyroidism
Defining Characteristic of
Hypocalcemia
Membranes, tingling of fingers
Tetany and cramps
Trosseau’s sign – carpal spasms
Chvostek’s sign – cheek twitching
Seizures, mental changes
EKG shows prolonged QT intervals
Treatment: Calcium carbonate / calcium
gluconate
Hypercalcemia
Hyperparathyroidism
Thiazide diuretics
Malignancy
Renal failure
Antacids
Serum calcium: > 10.5 mg/dl
EKG: shorted QT intervals
Treatment: calcium from the diet
Acid Base Balance
Acids – substance that can release hydrogen
ions
Bases – substance that can accept hydrogen
ions
Hydrogen ions determine whether a
solution is acidic, basic or neutral
Normal pH: 7.35 – 7.45
Buffer system: carbonic acid /
bicarbonate
Metabolic Acidosis
a base bicarbonate deficit
Normal HCO3; 22 – 26 mEq/L
Comes from too much acid and loss of
bicarbonate
S/s: pH < 7.35, increased K+ levels DKA
(Kussmaul’s, breathing)
Shock, stupor, coma
Nursing intervention – give HCO3
Metabolic Alkaloses
A base bicarbonate excess
A result of a loss of acid and a accumulation
of base.
S/s: serum pH > 7.45, increased serum
HCO3, serum K levels > 5.0 tetany,
convulsions, seizures
Nursing intervention – watch for S/s of
hypokalemia
Respiratory Alkalosis
A deficit of carbonic acid caused by
hyperventilation
Normal pCO2: 35 – 45
Decreased levels of pCO2, increased levels of
pH, HCO3 = normal.
Nursing intervention – monitor for anxiety
(breath in brown paper bag).
Respiratory Acidosis
A carbonic acid excess
Caused by condition that interferes with the
release of CO2 from the lungs (sedatives,
COPD, narcotics)
S/s: serum pH < 7.35,  pCO2 levels,
cyanosis
Nursing intervention: provide O2
Interpretation of Arterial Blood
Gases
Pyramid points:
If acidosis the pH is down
If alkolosis the pH is up
The reparatory function indicator is the
pCO2
The metabolic function indicator is the
HCO3
Step I
Look at the pH
Is it up or down?
If it is up: it reflects alkalosis
If it is down: it reflects acidosis
Step II
Look at the pCO2.
Is it up or down.
If it reflects an opposite response as the pH,
then you know that the condition is a
respiratory imbalance.
If it does not reflect as opposite response as
the pH – move to step III.
Step III
Look at the HCO3
Does the HCO3 reflect a corresponding
response with the pH?
If it does then the condition is a metabolic
imbalance
Example # 1
PO2
pH
pCO2
HCO3
BE
RR
O2
99.5
7.29
41 meq/L
19
- 17
22
2L/NC
Answer
Metabolic Acidosis
Example # 2
PO2
pH
pCO2
HCO3
BE
RR
Room air
98
7.50
30 meq/L
29 meq/L
+ 20
28
Answer
Respiratory Alkalosis
Total Parental Nutrition (TPN)
Hyperalimentation
Provide life sustaining therapy for patients
who cannot take adequate food by mouth
and who consequently are at risk for
malnutrition and its effects.
Indications for TPN
Perioperative
nutrition
Critical illness
Cancer cachexia
Liver failure
Renal failure
Inflammatory bowel
disease
Short
bowel
syndrome
Pulmonary disease
HIV
Pregnancy
Energy Requirement
Hypometabolic state
20 Kcal/kg
x
e.g. 70 kg man
1, 400 Kcal
Hypermetabolic state
(sepsis trauma)
40 Kcal/kg
x
e.g. 70 kg man
1, 800 Kcal
Conditionally Essential Nutrients
Glutamine –
immunocyte
fuel
for
enterocyte
and
Nucleotides – mediators for many metabolic
process
Branched chain – regulates muscle amino
acid, protein breakdown
Conditionally Essential Nutrients
SAM (S-adenosyl methionine) – normalizes
cell wall fluidity
Short chain fatty acid – fuel for colonocyses
Omega 3 fatty acids – promotes production
of prostaglandin
Commercially Available TPN
Nutripack 1, 200 Kcal, 1, 900 Kcal
Nutroflex 1, 200 Kcal, 1, 900 Kcal
Kabiven 1, 400 Kcal
Vitrimix
Intralipids
Vamin glucose
Vamin 14
Nephrosteril
Infusion Technique and Patient
Monitoring
1. Peripheral line: isotonic fat solution, shortterm
2. Central venous line: long-term,
glucose as the chief energy source
using
Fluids
Isotonic Fluids (Crystalloids)
a. Saline (Plain NSS)
154 meq Na
0.9%
 Hypovolemic shock
Fluids
Hypotonic Fluids
a. ½ NSS = 77 meq Na
= 0.45%
b. Dextrose in water
D5water = 5 grams glucose
D10water = 10 grams glucose
For hypernatremic patients
Fluids
Hypertonic solution
3% NaCl
 Use in hyponatremic patients
NaHCO3
 For acidotic patients
Fluids
Polyionic solutions
1. Ringers (Plain LR)
2. Lactated ringers
3. KCl
Use for diarrhea
Fluids
Colloids
Starch (Hydroxyethyc Starch)
a. Haeteril (10% or 5%)
b. Haemacel
c. Gelafurdin
 Hypovolemic shock
Thank you!