Fluid Imbalance PDF

osmolality/osmolarity (serum and urine) (concentration) I. Isotonic Imbalances -same *- no shifting of fluid* A. Hypovolemia -- low blood volume 1. Extracellular volume depletion 2. Water and electrolytes lost in same proportion 3. Etiology a. Decrease in intake of fluids: decrease IV fl...

osmolality/osmolarity (serum and urine) (concentration) I. Isotonic Imbalances -same *- no shifting of fluid* A. Hypovolemia -- low blood volume 1. Extracellular volume depletion 2. Water and electrolytes lost in same proportion 3. Etiology a. Decrease in intake of fluids: decrease IV fluids/ not drinking enough water b. Decrease in extracellular volume: vomiting, hemorrhaging, diarrhea 4. Pathophysiology a. Volume deficit → decreased CHP & filtration b. Cells deprived 5. Clinical Manifestations of hypovolemia a. Tissue dehydration: decreased skin turgor (elasticity) b. Decreased blood volume c. Decreased tissue perfusion B. Hypervolemia: increase in volume of blood 1. Excess extracellular fluid volume 2. Water and electrolytes gained in same proportion 3. Etiology a. Increased administration of isotonic fluids: excess IV fluid b. Increased dietary intake of NaCl c. Disease states - chronic renal failure, liver failure, heart failure - hyperaldosteronism (RAAS system: attachment) d. Expansion of extracellular space and circulatory overload: heart working harder 4. Clinical Manifestations a. Edema: swelling b. Increased BP and bounding pulse: strong pulse c. Urine output ↑ d. Weight gain: water weight e. Shortness of breath: Pressure on lungs; fluid around alveoli C. Edema: expansion or accumulation of interstitial fluid volume (Third-space shift) -from plasma to interstitial space: cells/tissues 1. Fluid Shifts from plasma (intravascular) to interstitial spaces → connective tissues 2. Etiology b\. Increased blood volume c\. Venous obstruction: increased pressure on the venous system that prevents the capillary from emptying to the venous system. d\. Decreased serum albumin: don't have osmotic pressure to keep fluid in 3. Pathophysiology 4. Clinical Manifestations: types of edema a. Pitting: pushing on the swelling and a indentation forms b. Weeping: fluid seeps through the pores of the skin II\. Osmolar Imbalances A. Hypo-osmolar (Hypotonic) Imbalance: excess retention of free water or solute loss (water intoxication) 1. Etiology a. Excess water intake b. End-stage renal failure c. Inappropriate ADH release 2. Pathophysiology a. Movement of water -\> into cell b. Cellular swelling 3. Clinical Manifestations a. Decreased serum osmolality b. Decreased hematocrit (hemodilution) - \% of blood volume that is made up of RBC's c. Low urine specific gravity d. Central nervous system changes B. Hyperosmolar (Hypertonic) Imbalance: excess concentration of ECF (water deficit) 1. Etiology a. Decreased water intake b. Insufficient intake of free water c. Increased loss of free water d. Excess intake of hypertonic solutions: high glucose IV's 2. Pathophysiology a. Hypertonic ECF environment: in the vessel but outside the cell b. Shrinkage of cells 3. Clinical Manifestations a. Elevated serum osmolality: high blood concentration b. Increased hematocrit (Hemoconcentration): high RBC concentration c. High urine specific gravity: concentrated urine d. Tissue dehydration: pinch the skin above the clavicle e. Polydipsia: increase in thrist f. Central nervous system changes