5% dextrose in 1/2 NS?

  1. 1
    I don't understand this. I know of 5DW and 1/2 NS but combining them together? Would this be isotonic, hyper/hypotonic? Can somebody help me figure this out?

    thanks
    l.a.m.b likes this.

    Get the hottest topics every week!

    Subscribe to our free Nursing Insights: Student Edition newsletter.

  2. 14 Comments...

  3. 8
    This is a standard IV solution. I'm thinking that what may be confusing you is the way it is written. It is written a number of different ways:
    • D5 1/2 NS
    • D5/0.45 NS
    • Dextrose 5% in 0.45% Normal Saline
    • Dextrose 5% in 1/2 Normal Saline
    • 5% Dextrose in 0.45% Normal Saline
    • 5% Dextrose in 1/2 Normal Saline
    It is a hypertonic solution. A hypertonic solution is one that has an osmolality greater than 340 mOsm/kg. Hypertonic solutions exert more osmotic pressure than the extracellular fluid so when these solutions are infused, fluid gets pulled into the vascular system. You want to monitor patients receiving any hypertonic solutions for fluid overload, particularly if they are being given at a rapid rate of infusion.

    The osmolality of 5DW and 1/2 NS is 405 m/Osm/liter and it's pH is about 4.4. It contains 50 grams of dextrose and 77 mEq of sodium and 77 mEq of chloride. The remainder is just sterile water.
    Last edit by Daytonite on Oct 11, '07
    gigglestarsRN, kywoodrd, Mike R, and 5 others like this.
  4. 0
    loved your answer. can you explain to me how hypotonic fluids work and LR?
  5. 13
    Quote from l.a.m.b
    loved your answer. can you explain to me how hypotonic fluids work and LR?
    Hypotonic solutions have an osmolality of less than 240 mOsm/liter. They exert less osmotic pressure than the fluid in the extracellular compartment which allows water to be drawn from the extracellular fluid. Blood cells will draw these solutions into them causing the blood cells to swell and burst. There is only one hypotonic solution in common use and that is 0.45% sodium chloride (1/2 Normal Saline). It has an osmolality of 155, a pH of 5.6, and contains 77 mEq of sodium and 77 mEq of chloride. Continuous infusion can cause dilution and depletion of electrolytes because of the small amount of sodium in this particular mixture resulting in hyponatremia. Because there are no calories in the solution, the patient is going to become calorie depleted as well if it is infused for a long period. Isn't it interesting that adding 5% Dextrose to it to make 5% Dextrose in 0.45% Normal Saline makes it a hypertonic solution?

    Lactated Ringers solution has an osmolarity of 275 mOsm/liter and a pH of 6.6. It contains 130 mEq of sodium, 4 mEq of potassium, 3 mEq of calcium, 109 mEq of chloride, and 28 grams of lactate. It is an isotonic solution. It is also called Hartmann's solution. It is primarily used to treat hypovolemia and when the patient's oral intake is limited, absent or fluid losses are very high. It does not, however, supply enough electrolytes for maintenance and does not contain any magnesium. The lactate is a buffer that when metabolized produces bicarbonate. Complications connected with the infusion of LR (Lactated Ringers) are overhydration, electrolyte excess (particularly sodium), electrolyte dilution, and calorie depletion. Patient can also develop metabolic alkalosis if LR is run over long periods of time. It shouldn't be used in patients with liver disease because the lactate is metabolized in the liver. You will commonly see LR used for surgical patients. Adding 5% dextrose to LR makes the solution hypertonic.

    Isotonic solutions have the same tonicity as plasma so that when they are infused into a vein, water neither enters or leaves the cells. These kinds of IV solutions are used to expand the extracellular fluid volume and do not cause any fluid to move from into or out of the blood cells. Isotonic solutions have an osmolality of 240 to 340 mOsm/liter. Other isotonic solutions are:
    • 0.9% Sodium Chloride
    • 5% Dextrose and Water
    • Ringer's solution
    • 2.5% Dextrose in 0.45% Sodium Chloride
    • 2.5% Dextrose in 1/2 strength Lactated Ringer's
    • 6% Dextran and 0.9% Sodium Chloride
    • 10% Dextran and 0.9% Sodium Chloride
    The only difference between Ringer's solution and Lactated Ringer's solution is that Lactated Ringer's has the 28 grams of lactate in it. Otherwise, the solutions have the identical other components.
    gigglestarsRN, kywoodrd, gdgrrrl, and 10 others like this.
  6. 0
    Is there such a thing as D5W/0.5 NS???
  7. 0
    i dont think so.... i know there is a .45% ns though. anything combined with 5% or 10% dextrose is HYPERtonic...
  8. 0
    Quote from sewnew
    Is there such a thing as D5W/0.5 NS???
    Nothing standard. Pharm can technically make any number of combinations of fluids by mixing inhouse but that would be so expensive you will never see it.
  9. 2
    Keep in mind D5W 1/2NS is hypertonic for about 5 minutes or so. The dextrose is quickly metabolized in about 5 minutes leaving only .45NS, turning hypotonic.
    kywoodrd and jelly221,RN like this.
  10. 0
    Thank you for the replies. I contacted the instructor and it was a typo on the slide. She had meant D5W/0.45 NS.
  11. 0
    Quote from Asystole RN
    Keep in mind D5W 1/2NS is hypertonic for about 5 minutes or so. The dextrose is quickly metabolized in about 5 minutes leaving only .45NS, turning hypotonic.
    Interesting...If that is the case, would D5W 1/2 NS still be contraindicated in a dehydrated patient?


Nursing Jobs in every specialty and state. Visit today and Create Job Alerts, Manage Your Resume, and Apply for Jobs.

A Big Thank You To Our Sponsors
Top