Would an intravenous injection of a 085 NaCl solution give t

Would an intravenous injection of a 0.85% NaCl solution give the same osmotic pressure to the cells of the bloodstream as a 0.85% NaCl dextrose (glucose) solution? Is the osmotic pressure of 0.85% NaCl and 5% dextrose the same?

Solution

No, the osmotic pressure of  0.85% NaCl solution and the osmotic pressure of 0.85% NaCl dextrose (glucose) solution is different. Addition of dextrose increases the osmotic pressure. Adding 5% dextrose increases the osmotic pressure. Every 50 g./lit adds 278 mOsm to the intravenous fluid. The osmotic pressure exerted by 0.9% NaCl is, 308 mOsm/liter. The osmotic pressure exerted by 0.85% NaCl and 5% dextrose is same, they are iso-osmotic.

In hospitals, 5% dextrose and normal saline are used as intravenous infusions because they are isotonic with the blood.