KIDENY AND HEMODIALYSES

KIDENYAND HEMODIALYSISKIDNEY AND HEMODIALYSESTITELESKidney DescriptionAnatomy of kidneyFunction of KidneyKidney DiseasesSave your KidneyArtificial kidneysDialysis machinesDialyzer TypesBlood pumpUltra filtrationDialysis Fluids Concentration Perfect HemodialysisKidney DescriptionThe kidneys are a pair of vital() organs that perform many functions to keep the blood clean and chemically balanced. The kidneys are bean ( )-shaped organs which have two parts.they are located near the middle of the back, just below the rib cage, one on each side of the spine.It have 150 gm for any part and also dimensions (10*5*2.5)cm.The Renal Artery ( )enters the kidney to pump unclean blood and Renal Vein extract pure blood from kidney after purification.

KIDNEY AND HEMODIALYSESAnatomy of kidneyNephron :The actual removal of wastes occurs in tiny units inside the kidneys which is nephron. Each kidney has about a million nephrons

Medulla:. The medulla or inner region of the kidney which nephrons found I n contains the loops of Henle Cortex: The cortex or outer region of the kidney contains the glomeruli and Bowman's capsules where filtration occurs

renal pelvis :represents the funnel((-like dilated proximal part of the ureterRenal Artery :which carry blood from Artery to Kidney.Renal vein : which take blood from nephrons to heart.Ureter: which nephrons pour waste product init to send them to Bladder.

Function of KidneyThe kidneys are sophisticated reprocessing machines. Every day, a persons kidneys process about 200 quarts( )of blood to sift out about 2 quarts of waste products and extra water. The wastes and extra water become urine, which flows to the bladder through tubes called ureters. The bladder stores urine until releasing it through urination.The kidneys remove wastes and water from the blood to form urine. Urine flows from the kidneys to the bladder through the ureters.The actual removal of wastes occurs in tiny units inside the kidneys called nephrons. Each kidney has about a million nephrons. In the nephron, a glomeruluswhich is a tiny blood vessel, or capillaryintertwines with a tiny urine-collecting tube called a tubule. The glomerulus acts as a filtering unit, or sieve, and keeps normal proteins and cells in the bloodstream, allowing extra fluid and wastes to pass through. A complicated chemical exchange takes place, as waste materials and water leave the blood and enter the urinary system.

In the nephron (left), tiny blood vessels intertwine with urine-collecting tubesAt first, the tubules receive a combination of waste materials and chemicals the body can still use. The kidneys measure out chemicals like sodium, phosphorus, and potassium and release them back to the blood to return to the body. In this way, the kidneys regulate the bodys level of these substances. The right balance is necessary for life.

Kidney DiseasesMost kidney diseases attack the nephrons, causing them to lose their filtering capacity.The most common causes of kidney disease:Diabetes ( )is a disease that keeps the body from using glucose. If glucose stays in the blood instead of breaking down, it can act like a poison. Damage to the nephrons High Blood Pressure : High blood pressure can damage the small blood vessels in the kidneysPoisons :can lead to kidney disease. Some over-the-counter medicines can be poisonous to the kidneys if taken regularly over a long period of time,stone(),inflammation(),bunions() are causes kidney diseases

Save your KidneyPeople may be able to save their remaining kidney function for many years by controlling their blood glucosecontrolling their blood pressurefollowing a low-protein dietmaintaining healthy levels of cholesterol in the bloodnot smoking

HemodiaLysis machinesArtificial kidneysArtificial kidneys have semi-permeable membranes which are typically about 10-20 micrometers thick, have a surface area of about 100 m2, and have pores(( which are about 500 nm in diameter. Molecules with a molecular weight less than 5,000 pass through the the membrane fairly easily, molecules of intermediate weights (5,000 to 40,000) will pass slowly. Dialysis can only remove a small quantity of amino acids and drugs. Even though amino acids have molecular weights of 75-204, both amino acids and drugs bind to plasma protein and as a result they do not pass through the membrane.

Dialysis Process

Concerning the blood, dialysis performs 2 different functions that are normally done by healthy kidneys:Removing excess fluid.Removing waste like urea, and excess electrolytes (chemicals) like potassium, magnesium, sodium, etc.

The block diagram of a single-pass dialysis system is shown in Figure. In the single-pass system, the dialysis fluid is used at a rate of 500 ml/min.In this system a large amount of fluid is needed and therefore the dialysis fluid is continuously created from a concentrate in a mixing tank with a proportionating pump. The concentration of the fluid is checked by measuring the conductivity of the fluid in addition to the temperature and pressure.

Dialyzer TypesCoil dialyzer: An early design in which the blood compartment consisted of one or two long membrane tubes placed between support screens and then tightly wound around a plastic core. This design had serious performance limitations, which gradually restricted its use as better designs evolved. The coil design did not produce uniform dialysate flow distribution across the membrane. More efficient devices have replaced the coil design.Parallel Plate Dialyzer: Sheets of membrane are mounted on plastic support screens, and then stacked in multiple layers ranging from 2 to 20 or more. This design allows multiple parallel blood and dialysate flow channels with a lower resistance to flow. The physical size of the parallel plate dialyzers has been greatly reduced since their introduction. There have been major improvements which provide (1) thinner blood and dialysate channels with uniform dimensions, (2) minimal masking or blocking of membranes on the support, and (3) minimal stretching or deformation of membranes across the supports.Hollow Fiber Dialyzer: This is the most effective design for providing low-volume high efficiency devices with low resistance to flow. The fibers in the device are termed the fiber bundle. The fibers are potted in polyurethane at each end of the fiber bundle in the tube sheet, which serves as the membrane support.

Blood pumpblood pump, available with optional Carmeda Bioactive Surface or Trillium Biosurface, uses the strained forced-vortex pumping principle in which a series of smooth-surfaced rotating cones pull the blood into the vortex created by the rotation.As the blood flows toward the pump outlet, the air handling vortex energy created by these cones transfers to the blood in the form of pressure and velocity. The Bio-Pump Plus pump is constructed from molded polycarbonate parts and features a double-lip seal design over precision bearings for optimum strength, robust construction, and dependability.

UltrafiltrationThe process of water removal from the blood stream is called ultra filtration; the fluid removed is the ultrafitrate. The UF during dialysis is performed for the purpose of removing water accumulated by ingestion of fluid or by metabolism of food during the interdialytic period. It is essential to prescribe and control the fluid removal rate so that total fluid removed during dialysis will be equal to the total fluid gained since the previous dialysis or from the dry weight.

No hydrostatic pressure is applied. Triangles represent osmotic agent introduced to right compartment. This causes an early water shift to the right (ultrafitration), but this is later reversed if the osmotic agent is also small enough to diffuse along the concentration gradient from right to left. Thus only solutes of such size that they do not easily permeate the semi permeable membrane are capable of exerting a sustained osmotic force.The application of external pressure forces movement of water from left to right. Low molecular weight constituents will be swept through the membrane with this water (solvent drag.). In dialysis setting the pressure gradient is generated by manipulation if dialysis fluid parameters such as pressure volume or flow

Fluids Concentration DialysisSodium with 130 m mole/literPotassium with 1.5 m mole/ literMagnesium with (1-5) m mole /literCalcium with 3.25 m mole/literChloride with 95.75 m mole/literGlucose with 22.2 m mole/liter

Perfect HemodialysisHave a good efficiency for extracting poisons ((and waste products.Have a good extraction of unwanted water.Have a small Dialyzer size to good dial with blood.The materials which used in Dialyses is safe for blood and dont react with it.Finally ,it should be low cost and easy to maintain.