Question: is d5 half normal saline isotonic?
Answer: Most physicians have been taught to use 0.9 NaCl (normal saline) for boluses, and either dextrose 5% with 0.2 NaCl (D5 quarter-normal) or dextrose 5% with 0.45 NaCl (D5 half-normal) for maintenance. Both 0.2 NaCl and 0.45 NaCl are hypotonic fluids, 0.9 NaCl is considered isotonic.