Hemodialysis Te

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DIFFUSION The movement of particles from an area of

higher concentration to a lower concentration

Higher concentration of toxins in the blood

moves to a lower concentration of the dialysate solution

OSMOSIS The movement of fluids across a semi-

permeable membrane from an area of lesser concentration to higher concentration of particles

Excess water from the blood (lower

concentration)moves to the dialysate bath (higher concentration)

ULTRAFILTRATION Movement of fluid across a semi-permeable

membrane as a result of artificially created pressure gradient

Accomplished by applying a suction/negative

pressure to the dialysis membrane to attract excessive water

More efficient than osmosis This pressure forces salt and water out of the blood and

into the dialysate.The used dialysate with the blood wastes and excess fluid is taken away and drained.

is a method for removing waste products such as creatinine and urea, as well as excess water from the blood when the kidneys are in renal failure

1. Arterial blood passes through a DIALYZER (an artificial kidney) to remove wastes and excess water. semi-permeable membrane surrounding these tubes is very thin and allows only some particles to pass through

2. As blood moves through these tubes it comes into contact with a solution called DIALYSATE a liquid made from water, an acid solution and

a bicarbonate solution. The dialysate liquid is circulated around the outside of the hollow fibers.

3. As a result, some waste products and electrolytes in the blood will move from the blood side of the membrane into the dialysate solution and some molecules will move from the dialysate side of the membrane into the blood.

Large molecules such as blood cells and protein are kept inside the membrane but smaller molecules such as urea and creatinine (and other biological wastes) pass through the small holes of the dialyzers filters into the dialysate solution.

4.Cleansed blood returns to the patient via venous access

Two normally functioning kidneys filter about 180 litres of blood a day, extracting about two litres of waste and extra water. Your body produces hundreds of different waste molecules every second. Some of these molecules become waste products such as CREATININE & UREA, which are the result of the normal breakdown of muscle and food (known as metabolism). The by-product or waste products of metabolism are then turned into urine, which is contained in the bladder until it is expelled. People with kidney failure need the help of dialysis to get rid of these normal metabolic waste products.

Dialysis CAN

Remove waste products (e.g. urea, creatinine, phosphorus, etc.) Remove excess water

Correct high or imbalanced levels of potassium, chloride, sodium, etc. in the blood

Dialysis CANT

Automatically regulate blood pressureProduce hormones like Erythropoetin (EPO)

Regulate normal calcium levels

A few signs (symptoms) of not getting enough dialysis are: Weakness and tiredness Poor appetite Feeling sick to your stomach Trouble getting a good sleep Itchy skin Metallic taste in your mouth Difficulty in concentrating Reduced interest in sex Difficulty breathing, especially when exercising or laying down flat Swelling in your hands and feet Poor blood pressure control

Dialyze all the days youre supposed to

Dialyze for your full treatment timeFollow your diet and fluid restrictions Take your medications regularly Take care of your access and monitor your arterial and venous pressures.


K = CBi CBo x Qb CBiK - is clearance CBi -(concentration at the blood inlet) is the concentration of x solute in the blood entering the dialyzer (arterial sample) CBo -(concentration at the blood outlet) is the concentration of x solute in the blood leaving the dialyzer(venous sample) Qb -is blood flow rate in mL/min

For example, imagine that you wanted to calculate the clearance of urea in a patient for whom: CBi = 82 mg/dL (arterial BUN sample) CBo = 8 mg/dL (venous BUN sample) Qb = 350 mL/min Step 1: (82 8) x 350 82 Step 2: 74 x 350 82 Step 3: 0.9 x 350 = 316 mL/min Therefore, during each minute of dialysis, 316 mL of this patients blood has been cleared of urea.

is achieved by introducing dialysis solution into the peritoneal cavity using a silastic catheter that is inserted through the patient's abdominal wall.

1.This catheter is tunneled under the skin for stability and terminates in the peritoneal space. 2. Using this catheter, the dialysate solution is drained into the peritoneal space by gravity known as INFLOW

3. During DWELL TIME, the natural membrane lining of the peritoneal cavity acts as a dialysis membrane through which waste products and excess water from the body can pass through into the peritoneal dialysate fluid

4. This waste-containing dialysate solution is drained out of the abdomen into a plastic bag known as OUTFLOW and is discarded.5. A new quantity is reintroduced in the next cycle.


Intermittent PD Manually/ cycler machine Echnage rate 30 minutes to 2hours Most common is hourly rate: INFLOW:10min, DWELL Time:30min, OUTFLOW:20min

Continuous Ambulatory PD Continuous Cyclical PD

Acute Intermittent PD


Ambulatory PD done at home by trained pt. or caregiver Exchange of 4 or 5 times/day, 24/7 Before meals & at bedtime

Continuous Cyclical PD

Acute Intermittent PDContinuous Ambulatory PD


Cyclical PD

Overnight intermittent PD w/

prolonged morning dwell time 2-3L exchange @ night 2-3L dwell time in the morning Quiet machine & extra long tubing

must be STERILE Dry heating is used (heating cabinet, incubator, heating pad) It is a HYPERTONIC SOLUTION CONTENT: Electrolytes & minerals high concentration of glucose relative to the

patient's own blood Heparin Antibiotics Insulin

The highly osmolar dialysis solution causes water to move from the patient's circulation through the peritoneal membrane and into the dialysate fluid within the peritoneal cavity by the process of osmosis. Waste products and excess electrolytes move from the patient's circulation into the dialysate solution by the process of diffusion. Each exchange, that is draining of the old solution and replacing it with a fresh solution, takes about 45 min.

Less complication compared to HD Less efficient compared to hemodialysis 36-48hours PD = 6-8hours HD

Candidates: Hemodynamically unstable pt. Patients susceptible to rapid F&E and

metabolic changes (elderly, pulmonary edema, diabetic and CVD patients: severe HPN, heart failure) not a satisfactory technique in patients who are catabolic and produce high levels of nitrogenous wastes, i.e. sepsis, ARDS D


DESCRIPTION Kidney damage (e.g., protein in the urine) with normal GFR Kidney damage with mild decrease in GFR Moderate decrease in GFR


2 3

60 to 89 30 to 59


Severe reduction in GFRKidney failure

15 to 29Less than 15

Your GFR number tells your doctor how much kidney function you have. As chronic kidney disease progresses, your GFR number decreases

The diet for patients with end-stage kidney disease who are on dialysis is usually high in protein and low in sodium, potassium, and phosphorus. Fluid intake is also restricted.

STEPS TO TAKE: Speak to the registered dietitian at your dialysis center. Ask your dietitian to help you plan meals with the right amount of calories. Keep a diary of what you eat each day. Show this to your dietitian on a regular basis.

Ask your doctor and dietitian what your ideal body weight should be.IDEAL WT. GAIN: 1 1.5 KG IN BETWEEN TREATMENT

Weigh yourself each day in the morning. If you are losing too much weight, ask your dietitian how to add extra calories to your diet. If you are slowly gaining too much weight, ask for suggestions on safely reducing your daily calorie intake and increasing your activity level.

If you gain weight rapidly, speak to your doctor and dietitian. 1kg = 1L of fluid gain/ loss

A sudden increase in weight, along with swelling, shortness of breath and a rise in your blood pressure may be a sign that you have too much fluid in your body.

The purpose of this diet is to maintain a balance of electrolytes, minerals, and fluid in patients who are on dialysis. The special diet is important because dialysis alone does not effectively remove ALL waste products. These waste products can also build up between dialysis treatments.

The dialysis diet controls the intake of fluid, protein, sodium, potassium, and phosphorus. The amounts of these nutrients in the diet are based on your blood levels of sodium, potassium, phosphorus, calcium, albumin, and urea. These levels are measured before and immediately after a dialysis treatment. Fluid restriction is based on the amount of urine output and weight gain between dialysis treatments.

PROTEIN (1.2-1.3g/kg/day) Your body needs the right amount of protein for: building muscles, repairing tissue, fighting infections. Before dialysis