[alex_md]

First I would replace the VOLUME, so the answer sould be E. The patient has methabolic normal anion gap acidosis. His kidneys are trying to work hard to hold on to free water without any respect to osmolality! By restoring volume we will supress his high ADH and nornalize his sodium. Giving bicarb now is not correct. First need to restore perfusion. If you give the bicarb it will drive his K+ into the cells and may cause severe hypokalemia. I personally do not give bolus bicarb for if Ph> 6.9 but his not that sick, right?

PS: Low or high sodium is NEVER about sodium. It is ALWAYS about free water.
PPS: Hypertonic saline is givent in only ONE case in Medicine - Hyponatremic seizures. In all other cases it is considered malpactice. If you sodium increases by more then 10 in first 24 hours or so you will paralize the poor guy.