3)principles of treatment O treating primary disease ②0.9%NaCl 2. hypertonic dehydration (1 water loss sodium loss 2 Serum sodium> 150mmol/L plasma osmotic pressure>310mOsm/L3) principles of treatment ① treating primary disease ② 0.9%NaCl 2. hypertonic dehydration ① water loss > sodium loss ② serum sodium > 150mmol/L ③ plasma osmotic pressure>310mOsm/L