Fluid Volume Imbalances PDF

MAINTAINING FLUID AND ELECTROLYTE BALANCE MAINTAINING FLUID AND ELECTROLYTE BALANCE u DESCRIPTION: Homeostasis is a term that indicates the relative stability of the internal environment. The concentration and composition of body fluids must be nearly constant. u The kidneys pla...

MAINTAINING FLUID AND ELECTROLYTE BALANCE MAINTAINING FLUID AND ELECTROLYTE BALANCE u DESCRIPTION: Homeostasis is a term that indicates the relative stability of the internal environment. The concentration and composition of body fluids must be nearly constant. u The kidneys play a major role in controlling balance in fluid and electrolytes. u NURSING ALERT! If the patient has a fluid or an electrolyte imbalance, the nurse must closely monitor the patient’s cardiovascular, respiratory, neurological, musculoskeletal, renal, integumentary, and gastrointestinal status. FLUID VOLUME IMBALANCES FLUID VOLUME DEFICIT DESCRIPTION u Dehydration occurs when the fluid intake of the body is insufficient to meet the fluid needs of the body. u The goal of treatment is to restore fluid volume, replace electrolytes as needed, and eliminate the cause of the fluid volume deficit. TYPES OF FLUID VOLUME DEFICITS u Isotonic dehydration: Water and dissolved electrolytes are lost in equal proportions. Known as hypovolemia, isotonic dehydration is the most common type of dehydration. u Hypertonic dehydration: Water loss exceeds electrolyte loss. The clinical problems that occur result from alterations in the concentrations of specific plasma electrolytes. u Hypotonic dehydration: Electrolyte loss exceeds water loss. The clinical problem that occurs results from the fluid shifts between compartments, causing a decrease in plasma volume. CAUSES OF FLUID VOLUME DEFICITS u Isotonic dehydration: Inadequate intake of fluids and solutes; Fluid shifts between compartments; Excessive losses of isotonic body fluids u Hypertonic dehydration: Conditions that increase fluid loss, such as excessive perspiration, hyperventilation, ketoacidosis, prolonged fevers, diarrhea, early-stage kidney disease, and diabetes insipidus. u Hypotonic dehydration: Chronic illness; Excessive fluid replacement (hypotonic); Kidney disease; Chronic malnutrition ASSESSMENT Cardiovascular Thready, increased pulse rate; diminished peripheral pulses Decreased blood pressure and orthostatic (postural) hypotension Flat neck and hand veins in dependent positions Decreased central venous pressure Dysrhythmias Respiratory Increased rate and depth of respirations Dyspnea Neuromuscular Decreased central nervous system activity, from lethargy to coma. Skeletal muscle weakness Fever, depending on the amount of fluid loss Renal Decreased urine output (oliguria) Integumentary Dry skin Poor turgor, tenting Dry mouth Gastrointestinal Decreased motility and diminished bowel sounds Constipation Decreased body weight Thirst Laboratory Findings Increased serum osmolality Increased hematocrit Increased blood urea nitrogen (BUN) level Increased sodium level Increased urine specific gravity NURSING INTERVENTIONS 1. Prevent further fluid losses and increase fluid compartment volumes to normal ranges. 2. Provide oral rehydration therapy if possible and IV fluid replacement if the dehydration is severe; monitor intake and output. 3. In general, isotonic dehydration is treated with isotonic fluid solutions, hypertonic dehydration with hypotonic fluid solutions, and hypotonic dehydration with hypertonic fluid solutions. NURSING INTERVENTIONS 4. Administer medications, such as antidiarrheal, antimicrobial, antiemetic, and antipyretic medications, as prescribed to correct the cause and treat any symptoms. 5. Monitor electrolyte values and prepare to administer medication to treat an imbalance, if present. FLUID VOLUME EXCESS DESCRIPTION u Fluid intake or fluid retention exceeds the fluid needs of the body. u Also called overhydration or fluid overload. TYPES u Isotonic overhydration: Known as hypervolemia, results from excessive fluid in the extracellular fluid compartment. Only the extracellular fluid compartment is expanded, and fluid does not shift between the extracellular and intracellular compartments. u Hypertonic overhydration: The occurrence is rare and is caused by an excessive sodium intake. Fluid is drawn from the intracellular fluid compartment; the extracellular fluid volume expands, and the intracellular fluid volume contracts. TYPES u Hypotonic overhydration: Known as water intoxication. The excessive fluid moves into the intracellular space, and all body fluid compartments expand. CAUSES u Isotonic overhydration: Inadequately controlled IV therapy; Kidney disease; Long-term corticosteroid therapy u Hypertonic overhydration: Excessive sodium ingestion; Rapid infusion of hypertonic saline; Excessive sodium bicarbonate therapy u Hypotonic overhydration: Early kidney disease; Heart failure; Syndrome of inappropriate antidiuretic hormone secretion; Inadequately controlled IV therapy; Replacement of isotonic fluid loss with hypotonic fluids; Irrigation of wounds and body cavities with hypotonic fluids ASSESSMENT FLUID VOLUME EXCESS Cardiovascular Bounding, increased pulse Elevated blood pressure Distended neck and hand veins Elevated central venous pressure Dysrhythmias Respiratory Increased respiratory rate (shallow respirations) Dyspnea Moist crackles on auscultation Neuromuscular Altered level of consciousness Skeletal muscle weakness Headache, visual disturbances Paresthesias Renal Increased urine output if kidneys can compensate; decreased urine output if kidney damage is the cause. Integumentary Pale, cool skin Pitting edema in dependent areas Gastrointestinal Increased motility in the gastrointestinal tract Diarrhea Increased body weight Liver enlargement Ascites Laboratory Findings Decreased serum osmolality Decreased hematocrit Decreased blood urea nitrogen (BUN) level Decreased sodium level Decreased urine specific gravity NURSING INTERVENTIONS 1. Prevent further fluid overload and restore normal fluid balance. 2. Administer diuretics; initially, osmotic diuretics may be prescribed to prevent severe electrolyte imbalances. 3. Restrict fluid and sodium intake as prescribed. 4. Monitor intake and output; monitor weight. 5. Monitor electrolyte values and prepare to administer medication to treat an imbalance if present.  FLUID VOLUME DEFICIT FLUID VOLUME EXCESS Cardiovascular Cardiovascular Thready, increased pulse rate; diminished peripheral pulses Bounding, increased pulse Decreased blood pressure and orthostatic (postural) hypotension Elevated blood pressure Flat neck and hand veins in dependent positions Distended neck and hand veins Decreased central venous pressure Elevated central venous pressure Dysrhythmias Dysrhythmias Respiratory Respiratory Increased rate and depth of respirations Increased respiratory rate (shallow respirations) Dyspnea Dyspnea Moist crackles on auscultation Neuromuscular Neuromuscular Decreased central nervous system activity, from lethargy to coma. Altered level of consciousness Skeletal muscle weakness Skeletal muscle weakness Fever, depending on the amount of fluid loss Headache, visual disturbances Paresthesias Renal Renal Decreased urine output Increased urine output if kidneys can compensate; decreased urine output if kidney damage is the cause. Integumentary Integumentary Dry skin Pale, cool skin Poor turgor, tenting Pitting edema in dependent areas Dry mouth Gastrointestinal Gastrointestinal Decreased motility and diminished bowel sounds Increased mobility in the gastrointestinal tract Constipation Diarrhea Decreased body weight Increased body weight Thirst Liver enlargement Ascites Laboratory Findings Laboratory Findings Increased serum osmolality Decreased serum osmolality Increased hematocrit Decreased hematocrit Increased blood urea nitrogen (BUN) level Decreased blood urea nitrogen (BUN) level Increased sodium level Decreased sodium level Increased urine specific gravity Decreased urine specific gravity