09 Fluid

Water + Electrolytes

• 1 amp bicarb = 50 meq Na + 5 meq bicarb

• D5 + 1 amp = 50 meq / L Na

• LR

  • 130 meq Na

  • 4 K: Do not use for K problems

  • 1.5 Ca

  • 28 lactate: for acidosis

• D5 0.45% Na w/ 20 meq K = maintenance

  • can cause hyponatremia. NS as alternative

Hyponatremia

• < 135 meq

• pt:

  • increased risk of heart, liver, kidney dysfunction

  • post op patients, especially young women (estrogen sensitizes receptor response; stress stimulates ADH)

  • older patients with thiazide diuretics

  • malignancy - para neoplastics

  • psych illness

  • endurance athletes

• sx

  • no neurologic

  • neurologic: mental fog, gait instability, encephalopathy, seizures, cerebral edema

• dx

  • check Na. If hyponatremic: check serum osm, urine osm, urine Na

• rx

  • 3% NaCl to correct temporary sx and recheck 1-2 hours

  • if overcorrected and hyper Na

    • desmopressin

    • dextrose

  • treat hyperna: calculate free water deficit: [Na]-140/140) X TBW (50% in women, 60% in men)