NCP Fluid and Electrolyte Imbalances

Body fluid is composed primarily of water and electrolytes. The body is equipped with homeostatic mechanisms to keep the composition and volume of body fluids within narrow limits. Organs involved in this mechanism include the kidneys, lungs, heart, blood vessels, adrenal glands, parathyroid glands, and pituitary gland. Body fluid is divided into two types: intracellular (within the cells) and extracellular (interstitial or tissue fluid, intravascular or plasma, and transcellular, such as cerebrospinal or synovial fluids).


All plans of care specific to underlying health condition causing imbalance, e.g., DM, HF, upper GI bleeding, renal failure/dialysis.

Metabolic acidosis (primary base bicarbonate deficit)

Metabolic alkalosis (primary base bicarbonate excess)

Respiratory acidosis (primary carbonic acid excess)

Respiratory alkalosis (primary carbonic acid deficit)


1. Restore homeostasis.

2. Prevent/minimize complications.

3. Provide information about condition/prognosis and treatment needs as appropriate.


1. Homeostasis restored.

2. Free of complications.

3. Condition/prognosis and treatment needs understood.

4. Plan in place to meet needs after discharge.

Note: Because fluid and electrolyte imbalances usually occur in conjunction with other medical conditions, the following information is offered as a reference. The interventions are presented in a general format for inclusion in the primary plan of care.


Total body water, essential for metabolism, declines with age and also varies with body fat content and gender. It constitutes about 80% of an infant’s body weight, 60% of an adult’s, and as little as 40% of an older person’s weight.

Hypervolemia (Extracellular Fluid Volume Excess)


Excess sodium intake including sodium-containing foods, medications, or fluids (PO/IV)

Excessive, rapid administration of hypertonic (or possibly isotonic) parenteral fluids

Increased release of antidiuretic hormone (ADH); excessive adrenocorticotropic hormone (ACTH) production, hyperaldosteronism

Decreased plasma proteins as may occur with chronic liver disease with ascites, major abdominal surgery, malnutrition/protein depletion

Chronic kidney disease/acute renal failure (ARF)

Heart failure (HF)

Patient Assessment Database


May report: Fatigue, generalized weakness


May exhibit: Hypertension, elevated central venous pressure (CVP)

Pulse full/bounding; tachycardia usually present; bradycardia (late sign of cardiac decompensation)

Extra heart sounds (S3)

Edema variable from dependent to generalized

Neck and peripheral vein distension


May report: Decreased urinary output, polyuria if renal function is normal



May report: Anorexia, nausea/vomiting

Thirst (may be absent, especially in elderly)

May exhibit: Abdominal girth increased with visible fluid wave on palpation (ascites)

Sudden weight gain, often in excess of 5% of total body weight

Edema initially dependent, pitting may progress to facial/periorbital, general/anasarca


May exhibit: Changes in level of consciousness, from lethargy, disorientation, confusion to coma; aphasia

Muscle twitching, tremors, seizure activity

Hyperreflexia, rigid paralysis (severe hypernatremia)


May report: Headache

Abdominal cramps


May report: Shortness of breath

May exhibit: Tachypnea with/without dyspnea, orthopnea; productive cough



May exhibit: Fever

Skin changes in color, temperature, turgor, e.g., taut and cool where edematous


Refer to predisposing/contributing factors

Discharge plan DRG projected mean length of inpatient stay: depends on underlying condition considerations: May require assistance with changes in therapeutic regimen, dietary management

Refer to plan of care concerning underlying medical/surgical condition for possible postdischarge considerations.


Hematocrit: Elevated in dehydration, decreased in fluid overload.

Serum sodium: May be high, low, or normal (between 135 and 145 mEq/L).

Serum potassium and BUN: Normal, or decreased in fluid overload unless renal damage present.

Total protein: Plasma proteins/albumin may be decreased.

Serum osmolality: Usually unchanged, although hypo-osmolality may occur.

Urine sodium: May be low because of sodium retention.

Urine specific gravity: Decreased.

Chest x-ray: May reveal signs of congestion.