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Peritoneal dialysis

What is it?

• The kidneys are two bean-shaped organs located on either side of the spine, below the rib cage.

• The kidneys are very important because they perform three essential functions:
  • they remove waste products from the blood;
  • they regulate the amount of water and certain minerals that the body needs to stay healthy;
  • they produce hormones that control other body functions.
• In their elimination function, the kidneys “clean” the blood by removing waste products and excess water and mineral salts that form urine. The kidneys specifically eliminate:
  • waste products: Urea is a waste product produced by the breakdown of proteins absorbed from food and creatinine is a waste product produced by muscle use. Some drugs also produce waste products through their breakdown. The elimination of wastes products by the kidneys prevents the onset of many ailments.
  • excess water: The body must contain the right amount of fluids to function properly. The kidneys ensure the balance of liquids by keeping the necessary amount of water in the tissues and by removing the surplus. This balance stabilizes the blood pressure and prevents swelling.
  • excess mineral salts: Mineral salts (eg, sodium, potassium, calcium, phosphorus) must be present in adequate amounts in the blood and body fluids for the body to function properly. Excess minerals are eliminated by the kidneys to prevent complications (eg, irregular heartbeat, muscle cramps, brittle bones, etc.).
  • excess acids: The balance between the acidity and alkalinity of the body (or acid-base balance) is essential to maintain good health. The kidneys play an essential role in maintaining this balance by producing acidic urine (to remove excess acids in the urine) or basic urine (to keep the necessary acids in the blood). This balance contributes to the healthy growth and development of the. The pH of a solution (eg, urine) is a measure of whether it is acidic or basic.
• The elimination function of the kidneys can be imagined as a “washing machine” for the body, where the blood enters “dirty” (with waste) and leaves “clean” (without waste).
• In the production function, the kidneys make hormones. Hormones are substances that circulate in the bloodstream and act as “messengers” to influence certain body functions (eg, control of blood pressure, production of red blood cells and maintenance of adequate calcium levels in the body). More specifically, the kidneys make or help make theses important hormones:
  • renin: helps maintain normal blood pressure;
  • erythropoietin: stimulates the bone marrow to produce red blood cells and thus avoid anemia;
  • calcitriol (active vitamin D): helps to strengthen bones and maintain adequate levels of calcium in the blood. Calcium is necessary to keep bones healthy.
• Let’s get back to the elimination function of the kidneys. The absorption of food through the stomach and intestines produces waste. These wastes end up in the bloodstream. Every minute, about 20% of the total volume of blood in the body flows through the kidneys via the renal arteries. After the kidney filters the blood, the cleaned (or purified) blood then returns to the circulation via renal veins.

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• The cleaning of the blood is done by filtration. Each kidney contains more than a million small units (nephrons). Each nephron consists of a tiny filter, the glomerulus, connected to a small tube (tubule).
• Blood coming from the renal arteries is filtered through the glomeruli, which retain red blood cells and proteins and allow water to pass into the tubules. This is the beginning of urine formation. The good elements (eg, minerals, vitamins, amino acids, glucose, etc.) and most of the water return to the blood from the tubules while the waste products remain in the urine. If some of the good elements are in excess, they are eliminated in the urine.
• The urine formed in the tubules flows into the funnel-like renal pelvis.

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• The renal pelvis extends outside the kidney into a long tube (ureter). Urine leaves the kidneys through both ureters and travels to the bladder, which is a pouch-like storage space. The urine stays in the bladder until the child urinates (pees). Urine leaves the bladder via a small tube (urethra) to the outside of the body.

• When a child drinks a lot of liquids, the kidneys produce and eliminate a lot of urine. On the other hand, when a child loses fluid through vomiting, diarrhea or sweating, the kidneys produce less urine to keep the body’s fluids in balance.
• When the kidneys are not functioning properly, there is a gradual build-up of waste products, minerals and water in the body. There is also a dysfunction in the production of hormones that control blood pressure, red blood cell production and calcium absorption. This is called kidney disease (or kidney failure).
• Kidney disease can be temporary or permanent. It can range from mild to severe and can progress over time. There are two types of kidney disease:
  • acute kidney disease: sudden loss of kidney function that can be caused by decreased blood flow to the kidneys, severe dehydration, toxicity (adverse effects) of certain medications, inflammation, or kidney blockage; acute kidney disease is usually temporary and lasts only a few weeks if treated promptly.
  • chronic kidney disease (CKD): gradual loss of kidney function (decrease in kidney function for three months or more) caused by a chronic disease; CKD may be mild and remain so, develop very rapidly, or progress slowly over several years; it may also worsen to the point where the kidneys stop functioning completely.
• The main causes of chronic kidney disease in children are:
  • congenital abnormalities of the kidneys or urinary tract; eg, malformations with obstruction (blockage of urine) or with reflux (urine that flows back up from the bladder to the kidneys),
  • kidney malformations (eg, dysplasia or hypoplasia of the kidneys),
  • glomerular diseases/glomerulopathies (eg, glomerulonephritis).
• As the kidneys deteriorate and chronic kidney disease progresses, symptoms vary depending on the severity of the disease:
  • fatigue, weakness,
  • vomiting, nausea,
  • loss of appetite, bad taste in the mouth,
  • weight loss,
  • swelling of the ankles, hands and eyelids,
  • shortness of breath,
  • insomnia at night and drowsiness during the day,
  • itching,
  • muscle cramps.
• Chronic kidney disease (CKD) is divided into stages based on how much the kidneys are functioning and able to filter waste products. Kidney/renal function is assessed by measuring the GFR (Glomerular Filtration Rate). Measuring GFR involves checking the clearance of creatinine, which is the amount of this waste product eliminated by the kidneys.

STAGES OF CHRONIC KIDNEY DISEASE (CKD)

Stage 1: CKD with normal renal function

• Renal function (GFR): >90%
• Symptoms: None
• Treatments:
  • Search for the cause
  • Medical follow-up

Stage 2: CKD with mild renal failure

• Renal function (GFR): 60-89%
• Symptoms: None
• Treatments:
  • Medical follow-up
  • Evaluation of the progression of the CKD

Stage 3A: CKD with mild to moderate renal impairment

• Renal function (GFR): 45-59%
• Symptoms: First symptoms may appear
• Treatments:
  • Same as stages 1 and 2
  • Tests to identify, prevent and treat complications (anemia, bone disorders)
  • Treatment of associated diseases

Stage 3B: CKD with moderate to severe renal impairment

• Renal function (GFR): 30-44%
• Symptoms: First symptoms may appear
• Treatments:
  • Same as stages 1, 2 and 3A
  • Preservation of veins (keep veins n good condition for possible hemodialysis treatments)

Stage 4: CKD with severe renal failure

• Renal function (GFR): 15-29%
• Symptoms: Worsening of symptoms
• Treatments:
  • Same as stages 1, 2 and 3
  • Discussion of future treatment options
  • Continued treatment and monitoring
  • Begin evaluation for renal transplantation

Stage 5: CKD with End-Stage Renal Disease (ESRD)

• Renal function (GFR): <15%
• Symptoms: Worsening of symptoms and appearance of new symptoms
• Treatments:
  • Depending on the nature of the symptoms and the assessment of the renal function: start of treatment to replace the elimination function of the kidneys
  • Registration on the transplant list

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• The healthcare team uses a variety of factors to determine the most appropriate treatment for the child with chronic kidney disease:
  • assessment of kidney function,
  • the nature of the symptoms experienced,
  • general health,
  • other factors (eg, the amount of protein in the urine, which means the kidneys are not working well).
• If chronic kidney disease is left untreated, it can lead to various complications:
  • anemia,
  • mineral and bone disorders,
  • fluid overload,
  • hypertension (high blood pressure),
  • neurological changes,
  • skin problems,
  • growth and development problems,
  • cardiovascular diseases (eg, left ventricular hypertrophy, calcium deposits in blood vessels),
  • dyslipidemia (increased cholesterol and triglycerides in the blood),
  • nutritional problems (eg, weight loss, weight gain, malnutrition),
  • etc.

TREATMENT OPTIONS FOR END-STAGE RENAL DISEASE (ESRD)

Dialysis

• Dialysis is a treatment that replaces the elimination function of the kidneys. It cleans the blood of waste and excess by passing it through a filter, much like healthy kidneys would do. Dialysis does not replace the production function of the kidneys.
• During dialysis, blood is on one side of the filter and a special solution (dialysate) is on the other side. The waste products from the blood pass through the filter and into the dialysate. Larger particles (eg, red blood cells) remain in the blood. The cleaned blood returns to the circulation and some of the waste is removed.
• Dialysis does not cure kidney disease, but it reduces the discomfort and improves the quality and length of life.
• In addition to dialysis, the child must take medication and follow a special diet to treat possible complications of kidney disease.
• Dialysis is sometimes used temporarily in situations of acute kidney disease.
• When the kidneys stop working permanently (as in end-stage renal disease), the child must have regular dialysis treatments. Unless the child has a kidney transplant or receives supportive care (see below), dialysis must be continued for life.

Kidney transplant

• This surgical procedure allows for the transplantation of a kidney in good condition from a living or cadaveric donor. This kidney takes over and does the work that the child’s kidneys can no longer do.
• The child must take anti-rejection medication for life.
• The transplant does not cure the kidney disease, but the child can live a more normal life.

Supportive care other than dialysis (conservative/palliative care)

• This treatment consists of medication and a special diet, which slows the deterioration of kidney function and reduces symptoms.
• For some children, a kidney transplant or dialysis is not a good option. Supportive care aims to improve the quality of life while minimizing suffering.

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• Even though a child is receiving dialysis treatment, the kidney disease is still present. The child must still follow a special diet and take certain medications to avoid complications.
• There are two kinds of dialysis. With the help of the healthcare team, the family chooses the type of dialysis that is best for the child based on their condition and lifestyle.

 

TYPES OF DIALYSIS

Hemodialysis

• Hemodialysis filters and cleans blood outside the body using a machine and an artificial filter called a dialyzer (or artificial kidney).
• This dialysis is made possible by placing a central venous catheter in a large vein at the base of the neck or by making an arteriovenous fistula (connecting a vein and an artery) in the arm. The machine removes blood through the catheter or fistula and passes it into the dialyzer. The dialyzer removes waste and excess water. The machine returns the cleaned blood to the circulation through the catheter or fistula.
• The blood is cleaned in this way three times a week or more frequently in young children.
• Each treatment usually takes four to five hours.
• Hemodialysis for children is done in the hospital; it can also be done at home, but less frequently.

 

 

 

 

Peritoneal Dialysis (PD)

• Peritoneal dialysis uses the peritoneum (thin membrane that lines the inside of the belly) to filter and clean the blood inside the body.
• A special solution (dialysate) is injected into the peritoneal cavity through a catheter installed in the peritoneum. The blood surrounding the peritoneum is brought into contact with the dialysate. Excess water and blood waste pass into the dialysate. The soiled dialysate (effluent) is drained out of the body through the same catheter.
• The exchange of solutions is mostly done at night with a machine (cycler) or can be done manually during the day.
• Peritoneal dialysis is usually done at home.

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• Peritoneal dialysis has several advantages:
  • gives autonomy and control in the child’s care,
  • allows for a more flexible schedule,
  • facilitates travel because it can also be done outside the home,
  • requires fewer days away from school and fewer trips to the hospital,
  • allows for less fluid restriction,
  • allows for less dietary restriction,
  • allows for better blood pressure control,
  • maintains remaining kidney function longer.
• With proper monitoring and daily care, peritoneal dialysis is effective and safe at home. It allows your child to continue to grow and develop well.

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https://complexcareathomeforchildren.com/peritoneal-dialysis/

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