FluidandElectrolyteManagementoftheSurgical.ppt

Fluid and Electrolyte Management of the Surgical Patient References: 克氏外科学（第15版） Maxwell,M.H. Etal: Clinical disorders of fluid and electrolyte metabolism 4th ed. New York, McGraw-Hill,1987. Mengoli,L.R.: Excerpts from the history of postoperative fluid therapy. Am. J.Surg.121:311,1971. 第一节 概述：Total body water  50%-70% of total body weight deuteriun oxide or tritiated water: 60% for male adult and 50% for female adult, both normal variation ±15%.(lean body mass and age) 52% and 47% with elder and 75%-80%for newborn infants, at 1 year of age, 65% Interstitial fluid:  Functioning components (90%) Nonfunctioning components(10%) connective tissue water and transcellular  water, which includes cerebrospinal and  joint fluids. Osmotic PressureThe physiologic and chemical activity of electrolytes depends on the number of particles (present per unit volume (moles or millimoles per liter), the number of electrical charges per unit volume( equivalents or milliequvalents per liter),and the number of osmoles or milliosmoles per liter) A Mole =the molecular weight of that substance in grams Eg:a mole of NaCl:58 grams(Na,23; Cl, 35) An Equivalent of an ion =its atomic weight expressed in grams divided by the valence.Eg:Ca++ 1 millimole equals 2 milliequivalents Osmole refers to the actual number of osmotically active particals present in solution. 1mmol NaCl, 2mOsm;1mmol Na2SO4,3 mOs; 1 mmol glucose,1mOsm. In each compartment the total number of osmotically active particles is 290 to 310 mOsm. The effective osmotic pressure depends on those substances that fail to pass through the pores of the semipermeable membrane. Such as sodium , glucose. The cell membranes are completely permeable to water. Any condition that alters the effective osmotic pressure in either compartment causes redistribution of water between the compartments. Hypokalemia 原因: 进少出多,移入胞内 临床表现: 肌肉兴奋性, 伴随缺水缺钠时的症状被掩盖,碱中度的症状 治疗:逐步补充!