10/8/2018 5:39 AM,外科病人的体液失调 Fluid Disorders of Surgical Patients,10/8/2018 5:39 AM,有用的概念 Useful Concepts,10/8/2018 5:39 AM,体液,脊椎动物进化于海水 脊椎动物身体的大约2/3是水 大多数脊椎动物的细胞外液的浓度是恒定的 体液=水+电解质+蛋白质+气体,10/8/2018 5:39 AM,Body Fluid 体液,Major Factors Affecting Body Fluids Age Gender Body fat,影响体液的主要因素 年龄 性别 体脂,10/8/2018 5:39 AM,Body Fluid 体液,Birth: 75-80% of body composition 1 year: 65% After puberty 60% males 50% females Older adults 50% males 40% females,出生： 75-80% 身体成分 1岁：65% 青春期后 60% 男 50% 女 老年 50% 男 40% 女,10/8/2018 5:39 AM,Body Fluid 体液,Intracellular Fluid (ICF) 40% BW for male 35% for female) Extracellular Fluid (ECF) 20% BW Plasma 5% BW Interstital Fluid 15% BW,细胞内液 (ICF) 40%体重（男） 35%体重（女） 细胞外液 (ECF) 20%体重 血浆 5%体重 组织间液 15%体重,10/8/2018 5:39 AM,Body Fluid 体液,细胞内液 Na+ CI- , HCO3 - & Protein - 细胞外液 K +, Mg +HPO42- & Protein -,10/8/2018 5:39 AM,Homeostasis 内稳态,Homeostasis, from the Greek words for “same“ and “steady“ Defined as the dynamic constancy of the internal environment despite changes in the external environment More a dynamic state in which internal conditions vary within narrow limits,内稳态一词来自希腊文“相同的”和“稳定的” 指无论外环境如何变化，保持内环境的动态稳定 内环境的多数的动态变化仅限于很窄的范围,10/8/2018 5:39 AM,Homeostasis 内稳态,Necessary for survival Most of these mechanisms operate by negative feedback Every organ system plays a role in maintaining homeostasis Nervous and endocrine systems are major communication systems,内稳态为生存所必需 大多数以负反馈机制调节 每一器官系统对维持内稳态具有作用 神经内分泌系统是主要的信息传递系统,10/8/2018 5:39 AM,Osmotic Pressure 渗透压,The pressure required to stop osmosis through a semipermeable membrane between a solution and pure solvent It is proportional to the osmolality of the solution. Normal value 290-310 mmol/L Formula 2(Na)+K+BUN+Glu,指为维持通过半透膜所隔开的溶液与纯溶剂之间的渗透平衡而需要的压力 与重量克分子渗透压浓度一致 正常值 290-310 mmol/L 公式 2(钠)+钾+尿素氮+葡萄糖,10/8/2018 5:39 AM,Fluid Balance 体液平衡,Water balance Water intake & loss are equal Electrolyte balance Ectrolytes absorbed in small intestine = amount lost in urine Acid base balance Hydrogen ions lost = hydrogen ions produced by metabolism,水平衡 水摄入=水丢失 电解质平衡 小肠吸收电解质量=尿中丢失量 酸碱平衡 氢离子丢失=代谢产生,10/8/2018 5:39 AM,Fluid Regulation 体液调节,Thirst Kidneys ADH Aldosterone Angiotensin II Prostaglandins Glucocorticoids Atrial Natriuretic Peptide,渴感 肾脏 抗利尿激素 醛固酮 血管紧张素 前列腺素 糖皮质激素 心钠素,10/8/2018 5:39 AM,水、钠代谢紊乱 Water and Sodium Disorders,10/8/2018 5:39 AM,Water Balance 水的平衡,10/8/2018 5:39 AM,Water Balance 水的平衡,NPO (non per os ) Anorexia,摄入水（INPUT）,10/8/2018 5:39 AM,Sodium 钠,Since sodium (Na) is the major osmotically active cation in the ECF compartment, changes in total body Na content are paralleled by changes in ECF volume,钠是细胞外液间隙中主要的渗透性活性阳离子，体内钠含量的变化与细胞外液容量的变化是平行的,10/8/2018 5:39 AM,Composition of GI Secretions 消化液成分,10/8/2018 5:39 AM,Dehydration 缺水,Dehydration is a condition that occurs when the loss of body fluids, exceeds the amount that is taken in Isotonic dehydration Hypotonic dehydration Hypertonic dehydration,缺水指体液丢失超过摄入 等渗性缺水 低渗性缺水 高渗性缺水,10/8/2018 5:39 AM,Dehydration 缺水,Normal RBCs,Isotonic Solution,Equal movement of water into and out of cells,Net movement of water out of cells,Net movement of water into cells,Shriveled RBCs,Swollen RBCs,Hypertonic Solution,Hypotonic Solution,10/8/2018 5:39 AM,Isotonic dehydration 等渗性缺水,Usually called fluid volume deficit, or hypovolemia in West Sodium loss = water loss Serum Na+ unchanged Plasma osmotic pressure unchanged,在西方通常称作容量缺乏或低血容量 钠丢失=水丢失 血清钠不变 血浆渗透压不变,10/8/2018 5:39 AM,Isotonic dehydration 等渗性缺水,Causes Excessive Fluid Losses Vomiting, diarrhea, GI suction, hemorrhage，intestinal fistulae, burn, intestinal obstruction, intra-abdominal infection, ect. Poor / Inadequate Fluid Intake,病因 体液丢失过多 呕吐、腹泻、胃肠减压、出血、肠瘘、肠梗阻、腹腔感染等 摄入不足,10/8/2018 5:39 AM,Isotonic dehydration 等渗性缺水,Clinical Manifestations Acute weight loss Urinary Output Anorexia Flattened neck veins Muscle weakness May not thirst Cool, clammy skin Skin turgorWeak, rapid pulse Orthostatic hypotension,临床表现 急性体重丢失 尿量减少 厌食 颈静脉萎陷 肌肉无力 可能不口渴 皮肤湿冷 皮肤弹性下降 脉搏细弱 体位性低血压,10/8/2018 5:39 AM,Isotonic dehydration 等渗性缺水,Management Replace ECF loss Address underlying cause IV route: Isotonic Solutions (Lactated Ringers, LR),处理 补充细胞外液量 去除病因 静脉补液：等渗溶液（乳酸林格氏液）,10/8/2018 5:39 AM,Hypotonic Dehydration 低渗性缺水,Definition Sodium losswater loss osmotic pressure 290mmol/L Na+水丢失 血浆渗透压 290mmol/L 血清Na+ 135mmol/L 也称作低血容量性低钠血症,10/8/2018 5:39 AM,Hypotonic Dehydration 低渗性缺水,Causes GI losses: Vomiting and diarrhea, intestinal obstruction, fistulas, drainage and NG tubes (chronic) Renal losses: Use of diuretics Extensive wounds (burn) Third spacing (peritonitis, pancreatitis, intestinal obstruction, ascites),病因 胃肠道丢失：长期呕吐和腹泻，慢性肠梗阻，肠瘘，引流管和鼻肠管 肾脏丢失：利尿剂的应用 大面积创伤(烧伤) 第三间隙丢失：(腹膜炎，胰腺炎，肠梗阻，腹水),