Question

Please discuss your idea about Fluid Volume Imbalances

Answer 1

FLUID VOLUME IMBALANCES

Fluid balance of body maintains in a healthy person ,because the intake of fluid equal to the excretion of fluids .Any alteration like excessive or lack of fluid intake,excessive or lack of fluid output can lead to fluid imbalances.

There are mainly 3 types of fluid imbalances

1.Dehydration

2.Fluid overload

3.Third space fluid

Dehydration

Dehydration is loss of water from extacellular fluid volume.(loss is from the vascular and intestitial fluids).It is a common and serious fluid imbalance that can leads to hypovolemia.

Etiology

• Lack of fluid intake
• Excessive fluid output or both
• Alteration in thirst hormones,lymphatic system, kidney .

There are three types of extracellular fluid volume deficts

• Hyperosmolar (hypertonic) fluid volume deficit:when water loss is greater than electrolyte(sodium)loss
• Iso-osmolar(isotonic) fluid volume deficit:when water and electrolyte (sodium) loss are equal.
• Hypotonic fluid volume deficit:when electrolyte loss is greater than fluid loss

Clinical manifestations

• Loss of body weight
• Since water is the major portion of body weight,even a mild dehydration can result in loss of body weight.
• Changes in inake and output
• It is another means of assessing fluid volume balance.Usually urine output is decrease in patients with dehydation.
• Changes in vital signs
• Dehydration can leads to decrease in systolic  blood pressure,a weak pulse, a decrease in centre venous pressure.
• Other manifestations include:dry mucous membrane of eye and mouth.cracked lips,furrows can be seen in tongue ,decreased turgor of skin.

Diagnostic findings

• Hyperosmolar fluid volume deficit creates hemoconcentration.
• Plsma sodium is also increased.

The following elevation are typical findings secondary to a hemoconcentrated state

• Osmolarity greater than 295mos/kg
• Plasma sodium level greater than 145 mEq/L
• Blood urea nitrogen greater than 25mg/dl
• Plasma concentration level greater than 120mg/dl
• Hematocrit greater than 55%
• Urine specific gravity greater tahn 1.030.

ManagementOral rehydration

• Intravenous rehydration
• Monitoring for complication of fluid restoration
• Correction of underlying problem

Fluid overload

It is the exracellular fluid volume excess.The water and sodium retained are in same proportion as they exist in the the ECF, si it is referred to as iso-osmolar fluid volume excess.

Etiology

• Administation of too much fluid or administration of fluids rapidly
• Failure to excreate fluid.
• Renal disorders
• Liver diseases
• Obstruction of lymphatic channels

Clinical manifestations

• Excessive fluidin the lungs leads to coughing,dyspnea and crackles
• Cardiovascular manifestations
• Edema(due to fluid accumulation)
• As the fluid excess increase in the cerebral cells ,lethargy occurs ,followed by seizure and then coma.

Diagnostic Findings

• The fluid volume excess the dialutes the concentration of solute.The findings include:
• Plasma osmolality less than 275 mOsm/kg
• Plasma sodium level less than 135mEq/L,depending on type of fluid volume excess.
• Hematocrit less than 45%
• Specific gravity less than 1.010
• BUN level less than 8 mg/dL

Management

• Restriction of sodium and Fluids
• Promoting urine output

Third spacing fluid

Its is the accumulation of fluids in the intestitial spaces.

Etiology

• Increased hydrostatic pressure
• Increased capillary permeability
• Decreasd serum protein levels
• Obstrution of venous portion of the capillary,or nonfunctional lymphatic drainage system.
• Liver diseases
• Kidney diseases

Clinical manifestations

Clinical manifestations of third spacing is similar to the manifestations of hypovolemia because fluid is not in the vascular system..

Diagnostic findings

• Decrease in hematocrift and BUN levels.
• Other abnormality depending on the area of body affected.

Management

• Replace fluid
• Stabilize other problems:some etiology of fluid shift is life threatening nad need to be treated imediately.For example,sepsis cause major increase in capillary permeability and must be treated with IV antibiotics.