Hypotonic IV fluids and liver disease

Jill2Shay · Sep 2, 2013

I mean to say I understand why not for lactated ringers solution, but not for a hypotonic solution.

Esme12, ASN, BSN, RN · Sep 2, 2013

When an isotonic solution is infused.......water neither moves into nor is pulled out of cells because roughly the same concentration of solute is on both sides of the membrane (the tonicity is equal). That's why isotonic solutions such as 0.9% sodium chloride, Ringer's lactate, Ringer's acetate, and dextrose 5% in water (D5W), are given to expand circulating volume and replace actual fluid losses. Because these solutions expand the intravascular compartment, closely monitor the patient for signs and symptoms of fluid overload, especially if he has a history of hypertension or heart failure.

Although D5W is isotonic in the bag, it acts like a hypotonic solution once it enters the bloodstream because simple sugars such as dextrose are the preferred energy source for cells. The low concentration of dextrose in D₅W is quickly consumed by the cells lining the vein and circulating in the bloodstream. Use this solution with caution in patients at risk for increased intracranial pressure (ICP).

Sodium lactate is a racemic salt....... which is oxidized by the liver to bicarbonate, and the dextro form, which is converted to glycogen. Lactate is slowly metabolized to carbon dioxide and water, accepting one hydrogen ion and resulting in the formation of bicarbonate for the lactate consumed. The liver converts lactate to bicarbonate, so don't give lactated Ringer's solution if the patient has a serum blood pH above 7.5 or liver disease as they won't be able to metabolize the lactate, worsening his alkalosis.

http://instructor.mstc.edu/instructor/randers/documents/IV%20fluids%20chart.pdf