【正文】 disadvantages ? Liquid tonicity higher (2 / 3) ? Can not be used as the maintenance media ? Na+ concentration is relatively higher to neonates and infants (proper diluted) . ? ORS： Rice soup 500ml+ salt Fried rice noodles 25g + salt + water 500ml (Cooking 2－ 3min) ?GNS: White sugar 10g + salt + water 500ml (boil) Simple preparation at home Severe dehydration intravenous ? Osmotic pressure of plasma (OPP) OPP= (crystal + colloid) osmotic pressure Na+ 142 Cation: K+ 5 (mmol) Ca++ Mg++ HCO3 27 Anion: Cl 103 (mmol) HPO4= 1 SO4= Organoanion 151 mmol/L 151 mmol/L OPP range： 280－ 320mOsm/L Concentration of electrolyte and calculation ? Osmotic pressure, osmol（ OSM） Dissolve 1mmol solute into 100ml water: 1mOsm. 100ml water 1mmol 1mOsm Concentration of electrolyte and calculation ? To non electrolyte 1mmol GS 1mOsm 2mOsm 1mmol Nacl ? To electrolyte 1mmol Cacl2 3mOsm Concentration of electrolyte and calculation Na:Cl=3:2 （ in plasma） Fluid isotonic Isotonic liquid: osmotic pressure similar with plasma Sodium isotonic: ?Isotonic: 150mmol sodium in 1000ml ?189。 correct acidosis ? Accumulative losses losses from onset to pretreatment ? ongoing losses continuing losses during treatment ? daily requirement to maintain basically physiological function Amount , position and time The first day fluid infusion ： Dehydration Fluid replacement=losses (Accumulation + ongoing + daily ) Accumulation ongoing daily total amount (ml/Kg) mild 50 10~30 60~80 90~120 moderate 50~100 10~30 60~80 120~150 Severe 100~120 10~30 60~80 150~180 Accumulation: accumulation losses Ongoing: Ongoing losses daily: Physiological requirement Severity clinical signs of dehydration mild moderate severe Water loss By weight Spirit Skin Mocous Anterior fontanel and eye ball Tear Urine output Peripheral circulation ＜ 50ml/kg ＜ 5% Slightly dispirited slightly agitated Slightly dry Slightly dry Slightly depressed Normal Slightly reduced normal 50～ 100ml/kg 5%～ 10% Dispirited Agitated Dry, pale Very dry depressed Reduced Little or No Little cool 100～ 120ml/kg ＞ 10% Extremely dispirited apathy, hypnody, a Gray mottled Parched depressed greatly No No urine output Cool, weak pulse,shock Dehydration Accumulation losses amount mild： 50ml/kg moderate: 50~100ml/kg severe： 100~120ml/kg Water supplement1: accumulation losses Amount , position and speed: according to the degree and quality of dehydration position isotonic ： 1/2 tonicity(1:1) hypotonic： 2/3 tonicity(4:3:1) Hypertonic:1/3~1/5 tonicity (1/3 tonicity) speed Principle: fast slow severe： bolus of isotonic fluid 2:1 isotonic : 20ml/kg(300ml) in 30’~1h(rapidly expand) others： 8~12h (8～ 10ml/（ kgh） 10~40ml/ position Water supplement2: ongoing losses daily requirement amount 1/3~1/5 tonicity (Physical main medium) speed ?In 24h, steady speed ?Acpany with stage2 60~80ml/ （ including oral） position Water supplement3: daily requirement To master three principles ?The volum of rehydration Amount Deficit fluid =(percentage of dehydration) (body weight in Kg) ?The type of fluid Composition Isotonic dehydration——1/2 tonicity solution Hypotonic dehydration——2/3 tonicity solution Hypertonic dehydration——1/3 tonicity solution ?The speed of liquidTime： four steps four steps (for fluid