腹膜透析基础

Pathways for Peritoneal Transport
腹膜转运途径
Endothelium 内皮
Interstitium 间质
Capillaries 毛细血管
Small solutes 小分子溶质
Macro molecules 大分子溶质
Water 水
Glucose 葡萄糖
Crystalloid Colloid osmosis osmosis 晶体渗透压 胶体渗透压
Mesothelium 间皮
Peritoneal tissue layer 腹膜组织层
Peritoneal Cavity (Dialysate) 腹腔（透析液）
Ultrafiltration
超滤
腹膜转运机理
小分子依靠弥散作用从毛细血管进入腹膜间质，再进入透析液中 透析液中的葡萄糖借助弥散作用从腹腔进入腹膜间质，加上弥散出来
间皮细胞、单核巨噬细胞、调理素
Components of the peritoneum as a dialysis membrane
腹膜（做为透析膜）的组成
The mesothelium
The stagnant fluid film
The interstitium Peritoneal capillaries
Terms used in convec源自文库ive transport
Sieving coefficient:
Ratio of solute being passed the barrier
Reflection coefficient
Ratio of solute being rejected by the barrier
The transport of solutes and water across a “membrane” that separates two fluid containing compartments.
The blood in the peritoneal capillaries
Dialysis solution in the peritoneal cavity
溶质依靠溶液之间浓度梯度透过半透膜（腹膜）进行的转运
弥散是小分子溶质清除的主要机制
影响弥散的因素
溶质分子的大小
腹膜表面积
静水压
溶质的电负荷
Convective transport
对流转运
Solute transport along with fluid movement
High during active ultrafiltration
2. Weigh 2-L bag of warmed 2.5% dextrose solution 3. Infuse over 10min(at a rate of 200 ml/min).
After each 400-ml infused, roll the patient from side to side. 4. Indwell for 4 hours. Ambulatory during dwell time. 5. Drain over 20 min. 6. After drainage,the bag is again weighed.
Stagnant capillary fluid The capillary endothelium itself The endothelial basement membrane
间皮
滞留液体层（阻力）
间质 腹膜毛细血管
毛细血管滞留液体 毛细血管内皮 内皮基底膜
A Basic Concept of Peritoneal Dialysis 腹透基本概念
1. 最好在使用2.5％葡萄糖腹透液留腹过夜8－12小时后，充分排放透析液 至少20分钟
2. 秤量袋装2升规格的已加温的2.5％葡萄糖腹膜透析液 3. 十分钟以上灌入腹内(速度200ml/min),每灌入400ml时让患者翻转身体. 4. 留腹4小时，留腹期间要求不卧床. 5. 排液时间20分钟以上. 6. 排液后再次秤量腹透液袋.
尿毒症毒素清除
Small solutes
Diffusion: Convective transport
Middle or large solutes
Peritoneal leak
小分子溶质
弥散 : 对流转运：
中等或大分子溶质
腹膜渗漏
Diffusion 弥散
Definition: Solute movement due to concentration gradient of two solutes between components across a semi-permeable membrane
决定水分渗透No的rm方al向os。molality 正常渗透压
Aquaporin mediated: 50%
水孔蛋白介导：50％，
H2O
（只能使水通过，也叫水通道）
Small pore: 50%
小孔：50％
High glucose-High osmolality
Peritoneal Space
高糖－高渗 腹膜部位
the circulation
从透析液到血循环的溶质
What is PET?
• Based on equilibration of solute concentration in dialysate to plasma and peritoneal glucose absorption.
• Dialysate to plasma concentration ratio of solutes such as creatinine, urea, potassium (D/P solutes): Dialysate creatinine concentration increases as creatinine diffuses into the peritoneal cavity due to the concentration gradient.
• Dialysate glucose concentration decreases as peritoneal glucose absorbs during a dwell time. • Drain volume is inversely correlated to solute transport rate.
• PET建立在血浆与透析液中溶质浓度的平衡以及腹膜对葡萄糖吸 收作用的基础上.
• 透析液和血浆中溶质浓度的比值(D/P)如肌酐、尿素、钾离子：随着
血液中肌酐顺着浓度梯度弥散入腹腔内，透析液中肌酐浓度逐渐增 加. • 留腹期间透析液中葡萄糖的浓度随着腹膜对葡萄糖的吸收而降低. • 引流量和溶质转运率负相关.
腹膜透析－ESRD治疗
中南大学湘雅医院 宁建平
How PD works
腹透原理
What is the peritoneal membrane ?
腹膜是被覆于腹腔的光滑 浆膜 脏层腹膜 壁层腹膜 腹膜凹陷 腹腔和腹膜腔
Components of the peritoneum
The mesothelium The interstitium
PET: Sampling
PET：取样
▪ Blood sample: 0,2,4 hour ▪ Dialysate sample:
200 ml of dialysis solution is drained into the bag, mixed well, a 10 ml sample is taken, and the remaining 190 ml is reinfused back
腹膜将下列两种液体分隔， 水分和溶质进行跨膜转运
腹膜毛细血管中的血液
腹腔中的透析液
PERITONEAL
腹 膜
TISSUE
BLOOD
腹膜组织
血液
Membrane
PERITONEA L CAVITY DIALYSATE 腹腔 透析液
Membrane model 腹膜模型
Removal of uremic toxins
PD水分清除：晶体渗透压
Osmotic Ultrafiltration
Movement of water from a chamber with lower osmotic pressure to higher one across a semi-permeable membrane
渗透超滤
水分通过半透膜Ca从pi低llar渗y s透pa压ce的毛腔细室血转管移到高渗透压的腔室，静水压和渗透压的矢量和
Main driving force for small solute removal Factors involved in diffusion
Size of solute Peritoneal surface area Hydrostatic pressure Electrical charge of solutes 定义:
Protect peritoneal organs Prevent friction of moving organs Host defense mechanisms:
Mesothelial cells, monocytesmacrophages, opsonins
支持、保护腹腔脏器 分泌滑液防止脏器移动时的摩擦 宿主的防御机制:
通过上述过程，毛细血管内的水被超滤出来，小分子和大分子毒素通过弥散 和对流作用也被排出，从而实现水和毒素的清除，同时伴随着透析液葡萄 糖被机体摄入。
Protein
Solutes from the circulation to
dialysis solutions
从血循环到透析液中的溶质
Solutes from dialysis solutions to
筛选系数（Sieving coefficient）： 溶质通过膜屏障的比例
反射系数（Reflection coefficient）： 溶质被膜屏障阻挡的 比例
筛选系数＝1－反射系数
影响对流转运的因素
溶质分子的大小 溶质的电负荷
Removal of Water in PD : Crystalloid Osmosis
Peritoneal Equilibration Test
腹膜平衡试验
Intraperitoneal Volume in Different Transport Groups
不同转运的腹膜在腹透时超滤量的变化
3250
Intraperitoneal volume, ml 腹腔内液体容量
3000 2750
Sieving coefficient=1reflection coefficient
Factors involved in convective transport
Size of solute
Electrical charge of solutes
定义：水分转运时伴随的溶质清除 高效超滤过程中对流作用大 对流转运应用的参数
2500
2250 0
60 120 180 240 300 360
Time, min
Wang et al. Nephrol Dial Transplant 13: 1242-49, 1998
H高转运 H-A高平均 L-A低平均 L低转运
PET: Protocol
PET：操作程序
1. Drain for at least 20min, ideally after an 8- to 12-hour overnight dwell using 2L of 2.5% dextrose solution
Macrophages/Monocytes
Peritoneal capillaries
Plays important role water and solute exchange
间皮 间质
巨噬细胞/单核细胞
腹膜毛细血管
在水和溶质的转换中起重 要作用
Role of the peritoneum 腹膜的功能
的小分子，使间质晶体渗透压升高，对毛细血管内水分形成超滤，水 就从毛细血管移出； 毛细血管中水分的超滤对毛细血管中大分子又产生对流作用，大分子 就进入间质，使局部胶体渗透压升高，水被进一步超滤，这样，水和 大分子然后分别进入透析液当中； 葡萄糖不断进入间质和毛细血管使渗透梯度下降，水的超滤下降。