水电解质平衡失调的处理.ppt

Fluid Electrolyte Management 水电解质平衡失调的处理 The surgical patient is liable to develop numerous disorders of body fluid volume and composition, some of which may be iatrogenic. Understanding the physiological mechanisms that regulate the composition and volume of the body fluids and the principles of fluid and electrolyte therapy is therefore essential for patient management. Body water its distribution体液的分布 Total body water (45-60% body weight) Intracellular (ICF) 2/3(40%bw) Extracellular (ECF)1/3 Plasma 25%(5%bw) Interstitial fluid75%(15%bw) Body water its distribution Composition ECF ICF Electrolyte = Proteins (Albumin Colloid osmotic pressure) Ions of body fluid Cation sodium Na+ potassium K+ ? magnesium Mg2+ Anion chloride Cl- organic phosphate P3 bicarbonate HCO3- proteins Regulation of body fluid balance体液平衡的调节 by kidneys: (1) filtration and reabsorption of sodium, which adjusts urinary sodium excretion to match changes in dietary intake (2) regulation of water excretion in response to changes in secretion of antidiuretic hormone. to keep the volume and osmolality of body fluid constant within a few percentage points despite wide variations in intake of salt and water. A corollary is that analysis of the composition. Regulation of body fluid balance体液平衡的调节 (1) filtration and reabsorption of sodium, which adjusts urinary sodium excretion to match changes in dietary intake (2) regulation of water excretion in response to changes in secretion of antidiuretic hormone. These two mechanisms allow the kidneys to keep the volume and osmolality of body fluid constant within a few percentage points despite wide variations in intake of salt and water. A corollary is that analysis of the