Ideally patients will recover quickly enough to replace the water deficit themselves by taking fluids orally.
There is no experimental evidence to justify using hypotonic fluids less than 0.45% sodium chloride
solution. However, if the osmolality is no longer declining despite adequate fluid replacement with 0.9%
sodium chloride solution AND an adequate rate of fall of plasma glucose is not being achieved then
0.45% sodium chloride solution should be substituted.