FLUID AND ELECTROLYTEFUNDAMENTALS Approximately 60% of typical adult weight Influenced by age, gender, body fat Men > Women; Obese < Nonobese Approx 2/3 is Intracellular within cells; Extracellular outside cells ECF: intravascular (3L plasma, 3L erythrocytes, leukocytes, thrombocytes), interstitial (11-12L surrounds cell, lymph), transcellular (1L, includes cerebrospinal, pericardial, synovial, intraocular, pleural fluid, sweat, digestive secretions) Loss can disrupt equilibrium. Loss of ECF into a space not contrib. to equilibrium is called third space shift, third spacingTHIRD SPACINGOccur in: ascites, burns, peritonitis, bowel obs, bleeding into joint/body cavity Dec urine OP despite adequate IT b/c fluid out of IV space, kidneys r/c less blood and compensate Inc HR Dec BP Dec CVP Edema Inc BW Imb in I&OElectrolytes Measured in milliequivalents (mEq) per liter (mEq/L)Gains and LossesGains: drinking, eating, IV/SC, enteral feeding***When balance is critical, all routes of G/L must be recorded and vol compared***Loss: kidneys (1-2L/day, 1mL/kg/h), skin (fever/burns inc insensible loss), lungs (greater w/ inc resp rate/depth or in dry climate), GI tract (diarrhea and fistulas inc losses)Avg Daily I&O in an Adult

IntakeOutput

Oral Liquids1300 mLUrine1500 mL

Water in food1000 mLStool200 mL

Water produced via metabolism300 mLLungs (Insens)300 mL

Sweat (Insens)600 mL

Approx Total gain2600 mLApprox Total loss2600 mL