Body fluids are
distributed in two
40% body weight
20% body weight
Interstitial fluid -
15% body weight
Plasma -5% body
Hormone secreted from the
zona glomerulosa cells of
Also called arginine vasopressin (AVP).
ADH is produced in neuron cell bodies
in supraoptic and paraventricular nuclei
of the Hypothalamus, and stored in
Promote the reabsorption of water in
the collecting duct.
The natriuretic peptide family
Four peptides of this family have been identified, including:
Atrial natriuretic peptide (ANP)
Brain natriuretic peptide (BNP)
C-type natriuretic peptide (CNP)
Diuretic and natriuretic actions
The sensation of thirst
Conscious desire for water
Major factor that determines fluid intake
Initiated by the osmoreceptors in
hypothalamus that are stimulated by
increase in osmotic pressure of body fluids
Also stimulated by a decrease in the blood
pressure through the baroreceptors.
The regulation of thirsty reaction
The stimulus sensed by osmoreceptor:
• Not a change in the extracellular fluid osmolality
• But a change in osmoreceptor neuron size or in the some intracellular substance.
Abnormalities in the Regulation of Body Fluid.
Fluid Volume Deficit (ECFVD)- Dehydration
Fluid Volume Excess- Over hydration
Extra Cellular Fluid Volume
A decrease in intravascular and interstitial fluids.
It is a common and serious fluid imbalance that results
in vascular fluid volume loss (hypovolemia).
Degrees of dehydration:
Types of dehydration:
Increased or normal serum sodium level
BUN (> 25 mg/d1)
Hyperglycaemia (>120 mg / dl)
Increased specific gravity of urine
Elevated hematocrit (>55%)
Management of Dehydration
Correction of the underlying problem
Assess for orthostatic hypotension
Assess muscle strength in legs
Orient the client to the environment
Remind the client to call for help before getting out of bed or
Help the client get out of bed or a chair
Provide, or remind the client to use, a walker or cane for
Provide adequate lighting at all times, especially at night
Keep the call light within reach, and ensure that the client can
Place the bed in the lowest position with the brakes locked
Place objects that the client needs within reach
Ensure that adequate handrails are present in the client's room,
bathroom, and hall
Encourage family members or significant other to stay with the
Extra Cellular Fluid Volume Excess/
ECFVE is increased fluid retention in the intravascular
& interstitial spaces (third spacing)
Administering fluids rapidly or in a large amount
Failure to excrete fluids:
o Heart failure
o Renal disorders
o Venous obstructions
o Decreased plasma proteins
o Excessive fluid ingestion
o Increased ADH & Aldosterone
Decreased or normal serum sodium level
BUN (<8 mg/dl)
Decreased specific gravity of urine
Decreased hematocrit (<45%)
Management of over hydration
ICFVE is treated by the addition of solutes to IV fluids.
Use of D5%, 0.45% Nacl will help to correct ICFVE
when the cause is water excess.
Oral fluids such as water and soft drinks should be
given in addition to water and ice chips.
IV therapy should be monitored every hour.
Monitor vital signs and intake- output
Weight should be checked daily to measure fluid gain or
Administer prescribed antiemetic as needed to allow
food and fluids to be ingested.
Safety measures are necessary when the client displays
Monitor cardiovascular, respiratory, neuromuscular,
renal, integumentary, and gastrointestinal status.
Prevent further fluid overload and restore normal fluid
Administer diuretics; osmotic diuretics typically are
prescribed first to prevent severe electrolyte imbalances.
Restrict fluid and sodium intake as prescribed.
Monitor intake and output; monitor weight.
Monitor electrolyte values, and prepare to administer
medication to treat an imbalance if present.
Electrolyte Balance and Imbalance
– Commonly defined as a serum sodium
concentration <135 mEq/L
– Hyponatremia represents a relative excess of
water in relation to sodium.
Hyponatremia is the most common electrolyte disorder
Acute hyponatremia (developing over 48hr or less) are
subject to more severe degrees of cerebral edema
sodium level is less than 105 mEq/L, the mortality is
Chronic hyponatremia (developing over more than 48hr)
experience milder degrees of cerebral edema
Develops as sodium and free water are lost and/or
replaced by inappropriately hypotonic fluids
Sodium can be lost through renal or non-renal routes
Vomiting, Diarrhea, fistulas, pancreatitis
Third spacing of fluids
ascites, peritonitis, pancreatitis, and burns
Cerebral salt-wasting syndrome
traumatic brain injury, aneurysmal subarachnoid
hemorrhage, and intracranial surgery
Must distinguish from SIADH
Acute or chronic renal insufficiency
Sodium deficit is more and the volume remains same.
Psychogenic polydipsia, often in psychiatric patients
Administration of hypotonic intravenous (5% DW) or
irrigation fluids ( sorbitol, glycerin) in the immediate
administration of hypotonic maintenance intravenous
Infants who may have been given inappropriate
amounts of free water
bowel preparation before colonoscopy or colorectal
Total body sodium increases, and TBW increases to a greater
Can be renal or non-renal
acute or chronic renal failure
dysfunctional kidneys are unable to excrete the ingested
cirrhosis, congestive heart failure, or nephrotic syndrome
Water shifts from the intracellular to the extracellular
compartment, with a resultant dilution of sodium. The TBW
and total body sodium are unchanged.
This condition occurs with hyperglycemia
Administration of mannitol
Determine cause of hyponatremia and to correct it.
If client has hyponatremia due to fluid volume excess,
intake of fluids will be restricted to allow the sodium to
If the serum sodium level falls below 125 mEq/L,
sodium replacement is needed.
For client with moderate hyponatremia 125 meq/ L I/V
saline solution (0.9% Nacl) or lactated Ringer solution
may be ordered.
When the serum sodium level is 115 meq / L or less, a
concentrated saline solution such as 3 % Nacl is
Monitor cardiovascular, respiratory, neuromuscular,
cerebral, renal, and gastrointestinal status of the client.
If hyponatremia is accompanied by a fluid volume
deficit (hypovolemia), IV sodium chloride infusions are
administered to restore sodium content and fluid
If hyponatremia is accompanied by fluid volume
excess (hypervolemia), osmotic diuretics are
administered to promote the excretion of water rather
Instruct the client to increase oral sodium intake and
inform the client about the foods to include in the diet.
If the client is taking lithium (Lithobid), monitor the
lithium level, because hyponatremia can cause
diminished lithium excretion, resulting in toxicity.
Hypernatremia is usually due to water deficit
Excess water loss : eg- heat exposure
Impaired thirst: eg - primary hypodypsia,
Excessive Na+ retention
Clinical features of hypernatremia
Excessive thirst, polyuria, nausea
Muscular weakness, neuromuscular
Altered mental status,focal
neurological deficit occasionally coma
correct water deficit
Rate of correction :
-Acute hypernatremia- 1mEq/L/hr
-Chronic hypernatremia-1mEq/L/hr or 10mEq/L over 24hr
-rapid correction may lead to cerebral edema
Determining & correcting the cause of the imbalance.
Extreme hypokalemia requires cardiac monitoring.
Oral potassium replacement therapy is usually prescribed for
Potassium is extremely irritating to gastric mucosa; therefore
the drug must be taken with Glass of water or juice or during
Potassium chloride can be administered intravenously for
moderate or severe hypokalemia & must be diluted in IV
Administration of potassium by IV push may result in
cardiac arrests. Potassium can be given in doses of 10 to
20 mEq/ hour diluted in IV fluid if the client is on heart
High concentration of potassium is irritating to heart
muscle. Thus correcting a potassium deficit may take
The administration of foods
that are high in potassium
help to correct the problem
as well as prevent further
Hyperkalemia is an Elevated potassium level over 5.0 mEq/L.
Retention of Potassium- Renal insufficiency, renal failure,
decreased urine output, potassium sparing diuretics.
Excessive release of Cellular Potassium - severe traumatic
injuries. Severe burns, severe infection, metabolic
Excessive IV infusions or Oral administration of
When serum potassium level is 5.0 to 5.5 mEq/L restrict
If potassium Excess is due to metabolic acidosis,
correcting the acidosis with sodium bicarbonate
promotes potassium uptake into the cells.
Improving urine output decreases elevated serum
When hyperkalemia is severe, immediate actions are
needed to be taken to avoid severe Cardiac disturbances.
The administration of foods that are low in potassium help
to correct the problem as well as prevent further
Monitor cardiovascular, respiratory, neuromuscular,
renal, and gastrointestinal status; place the client on a
Discontinue IV potassium and hold oral potassium
Prepare to administer potassium-excreting diuretics if
renal function is not impaired.
Initiate a potassium-restricted diet.
If renal function is impaired, prepare to administer
sodium polystyrene sulfonate (Kayexalate).
Prepare the client for dialysis if potassium levels are
Prepare for the IV administration of hypertonic glucose
with regular insulin to move excess potassium into the
Monitor renal function.
Teach the client to avoid foods high in potassium.
Instruct the client to avoid the use of salt substitutes or
other potassium-containing substances.
Determining & correcting the cause of hypocalcemia.
Asymptomatic hypocalcemia is usually corrected with oral
calcium gluconate, calcium lactate or calcium chloride.
Administer calcium supplements 30 minutes before meals
for better absorption and with glass of milk because vitamin
D is necessary for absorption of calcium from the intestine.
Intravenous calcium chloride or calcium gluconate
(10%) is given slowly to avoid hypertension,
bradycardia & other arrhythmias.
Chronic or mild hypocalcemia can be treated in part by
having the client consume a diet high in calcium.
Monitor cardiovascular, respiratory, neuromuscular, and
gastrointestinal status; place the client on a cardiac monitor.
Administer calcium supplements orally or calcium
When administering calcium intravenously, warm the injection
solution to body temperature before administration and
administer slowly, monitor for electrocardiographic changes,
and monitor for hypercalcemia.
Administer medications that increase calcium
absorption. i.e. Vitamin D aids in the absorption of
calcium from the intestinal tract.
Initiate seizure precautions.
Keep 10% calcium gluconate available for treatment of
acute calcium deficit.
Instruct the client to consume foods high in calcium.
Hypercalcemia is a serum level over 5.5 meq/L or 11 mg/L
Metastatic malignancy-lung, breast, Ovarian, Prostatic,
bladder, leukemia, Kidney.
Thiazide diuretic therapy.
Excessive intake of calcium supplements and vitamin D.
Gastrointestinal: Anorexia, Vomiting, Constipation
Mild to moderate hypercalcemia state –weakness
Severe hypercalcemic state-Extreme lethargy
Electro-cardiographic Changes: Shortened ST Segment and
lengthened QT interval.
Musculoskeletal: Bone pain, fracture.
Treatment consists of correcting the underlying cause.
Intravenous normal saline (0.9% Nacl) given rapidly
with furosemide to prevent fluid overload, Promote
urinary calcium excretion.
Corticosteroid drugs decrease calcium levels by
competing with vitamin D thus resulting in decreased
intestinal absorption of calcium.
If the cause is excessive use of calcium or vitamin D
supplements or calcium containing antacids these agents
should be either avoided or used in reduced dosage.
A newer form of drug therapy is etidronate di-sodium.
This drug reduces serum calcium by reducing normal
and abnormal bone reabsorption of calcium and
secondarily by reducing bone formation.
Monitor cardiovascular, respiratory, neuromuscular, renal,
and gastrointestinal status; place the client on a cardiac
Discontinue IV infusions of solutions containing calcium and
oral medications containing calcium or vitamin D.
Discontinue thiazide diuretics and replace with diuretics that
enhance the excretion of calcium.
Administer medications as prescribed that inhibit calcium
resorption from the bone, such as phosphorus, calcitonin,
bisphosphonates, and prostaglandin synthesis inhibitors
(aspirin, nonsteroidal anti-inflammatory drugs).
Prepare the client with severe hypercalcemia for dialysis if
medications fail to reduce the serum calcium level.
Instruct the client to avoid foods high in calcium.
Mild cases- treated with dietary restrictions
Teach client about balanced diet
Severe cases: phosphate supplementation
Hyperphosphatemia is defined as plasma
Causes of hyperphosphatemia
Excess intake of high phosphate foods
Excess vitamine D supplementation especially in renal
Impaired colonic motility
Mild cases- limit phosphate rich foods ( milk, ice-cream,
cheese, meat, fish)
Giving calcium, aluminium products that promotes
binding & excretion of phosphate.
Dialysis is the TOC in case of hyperphosphatemia with
Oral magnesium replacement (anta-acids)
Parenteral magnesium sulphate
Increase dietary intake of magnesium (chili, tofu, wheat
Initiate safety & seizure precautions in severe cases and
monitor all electrolytes.
Keep watch on rising magnesium levels.
Hypermagnesemia is defined as plasma magnesium
Causes of hypermagnesemia
Excessive anta-acid use
Clinical amnifestations are related to blocked release of
Acetylcholine from myoneronal junction which affects muscle
Loss of DTR
Prolonged QT, PR interval
Respiratory paralysis, loss of consiosness
Low magnesium diet (eat chicken, eggs, green peas, white
Decrease magnesium sulphate use
In severe cases saline infusion with diuretics is give to
promote magnesium excretion
IV calcium (antagonistic action)
If renal failure is also present than hemodialysis is done in
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1. The type of fluid used to manipulate fluid shifts
among compartments states is:
A. Whole blood
D. Normal saline
2. The balance of anions and cations as it occurs
across cell membranes is known as:
A. osmotic activity
B. Electrical neutrality
C. Electrical stability
D. Sodium potassium pump
3. A diet containing the minimum
daily sodium requirement for an adult would
A. no-salt diet
B. diet including 2 gm sodium
C. diet including 4 gm sodium
D. 1500 calorie weight-loss diet