KidneyCoach: Glossary of Commonly Used Terms

Take care of your body. It is the only place you have to live”
— John Rohnert

Glossary of Commonly Used Terms: Features definitions of terms found in the treatment of Kidney Disease.


Abdomen: The part of the body containing the internal organs. Lies between the pelvis and the chest cavity.

Access: A means to get into the body. Accesses to the bloodstream for hemodialysis are fistulas, grafts, etc. Access to the peritoneal cavity for peritoneal dialysis is a catheter.

Acute: Rapidly developing; severe; short duration.

Acute Renal Failure: Sudden and severe decrease in kidney function that is short term.

Ambulatory: Able to walk; movable.

Anemia: A condition in which there is a reduction of red blood cells.

Antibiotic: Medication used to kill bacteria and fight infection.

Anticoagulant: Medication that delays or stops the clotting of blood such as Coumadin or heparin.

Antihypertensive: Medication that lowers blood pressure.

Antiseptic: Chemical that stops growth and reproduction of bacteria and viruses, but doesn't necessarily destroy them as a disinfectant would.

Arterial Line: A tube that carries blood away from the body into the artificial kidney.

Arteriosclerosis: Hardening of the arteries.

Artery: A blood vessel carrying blood away from the heart to other parts of the body.

Artificial Kidney: A filtering device used with an artificial kidney machine to remove excess fluid and waste products from the body. Also known as "dialyzer" and "hemodialyzer."

Artificial Kidney Machine: A machine that supports and monitors the functioning of the artificial kidney (dialyzer). Also call "hemodialysis machine."


Bacteria: Single cell organisms, capable of rapid reproduction. They are present everywhere; some are harmless, others are known to produce infectious disease.

Bath: See "dialysate."

Benign: Not harmful in effect: in particular, (of a tumor) not malignant

Blood Chemistries: Measurement of certain chemicals in the blood.

Blood Flow Rate: In dialysis, the rate at which the patient's blood is pumped through the artificial kidney.

Blood Pressure: Pressure blood exerts on the walls of the blood vessels. This is expressed in two numbers, such as 120/80. The systolic (top) number is the pressure when the heart is contracting and the diastolic (bottom) number is the pressure when the heart is at rest.

Bruit: Sound produced by the blood flowing through a graft, fistula or shunt.

BUN (Blood Urea Nitrogen): Combination of waste products (nitrogen and urea) in the blood normally excreted by the kidneys.


Cadaver Donor: Someone who has died and whose kidneys have been donated for transplantation.

Calcium: Element found in the body. Important to bone growth and formation, blood clotting, nerve and muscle functioning and the activation of certain enzymes.

Carbohydrate: Category of food that is easily used by the body for energy.

Cardiac: Anything to do with the heart.

Catheter: A flexible, hollow tube through which fluids enter or leave the body. A catheter is implanted in the abdomen for peritoneal dialysis.

Chronic: Of long duration or recurring often.

Chronic Renal (Kidney) Failure: Damage to the kidneys that cannot be reversed, usually progressive in nature.

Clearance: Rate that waste products in the blood are removed through dialysis expressed in milliliters/minute.

Coagulation: The process of forming a blood clot.

Concentration: Strength of a solution.

Congestive Heart Failure: A condition in which the body is fluid over-loaded, causing the heart to pump less effectively. Congestive heart failure may result in excess fluid in the lungs.

Contaminate: Allowing microorganisms to contact a sterile area, making it unsterile and creating potential for infection.

Continuous Ambulatory Peritoneal Dialysis (CAPD): A form of dialysis in which dialysate drains into and out of the peritoneal cavity by gravity several times a day.

Continuous Cycling Peritoneal Dialysis (CCPD): A form of dialysis that uses a cycling machine to infuse and drain dialysate from the peritoneal cavity several times during the night while the patient sleeps.

Convulsion: Involuntary muscle contractions and relaxation.

Creatinine: One of the many waste products in the blood produced by normal tissue breakdown and removed by the kidneys, or by dialysis in patients with renal failure.

Cross-matching: Testing of blood and tissues to check compatibility of donor kidney and patient for kidney transplantation.

Culture: A sample of organisms taken from a site to identify the specific organism causing infection.


Dialysate: Solution containing water and chemicals (electrolytes) that passes through the artificial kidney to remove excess fluids and wastes from the blood. Also called "bath."

Dialysis: Cleansing the body of unwanted toxins, waste products and excess fluid by filtering them from the blood through a semipermeable membrane.

Dialysis Treatment Plan: Regimen based on the individual needs of the chronic renal failure patient to reestablish physical balance .

Dialyzer: See "artificial kidney."

Diffusion: Passage of particles from a solution of high concentration to a solution of low concentration resulting in an even distribution of particles.

Disinfectant: An agent which will kill most microorganisms (bacteria, viruses) it contacts.

Dry Weight: The weight of a dialysis patient when excess fluid has been removed. Also known as "ideal weight."

Dwell Time: Length of time dialysis solution stays in the peritoneal cavity during peritoneal dialysis.


Edema: Swelling or puffiness due to buildup of excess fluid in the tissues most noticeable in ankles, hands, and face. Occurs in dialysis patients as a result of excess fluid intake or decreased ultrafiltration.

End-Stage Renal Disease (ESRD): Stage of kidney damage that requires dialysis or kidney transplantation to maintain life. Another term for permanent kidney failure.

Exchange: The process of changing used dialysate for fresh solution in peritoneal dialysis.

Exit Site: The area where the needles enter or exit through the access. Also, where a peritoneal dialysis catheter or subclavian catheter exits the skin.


Fistula: The surgical joining of an artery and a vein so that the vein enlarges due to the flow of arterial blood. A fistula is a type of access, also known as an "arteriovenous fistual."

Fluid Overload: Point at which extra fluid in the body causes edema, difficulty in breathing, or extra strain on the heart.


Glomerulonephritis: Inflammation of the kidney's filters.

Graft: In dialysis, surgical placement of a material between an artery and vein to create a circulatory access for hemodialysis. Graft also refers to a transplanted kidney.


Hematocrit: The ratio of red blood cells to whole blood.

Hemodialysis: Removal of excess fluids and waste products by passage of blood through an artificial kidney.

Hemodialyzer: See "artificial kidney."

Hemoglobin: Protein portion of the red blood cell which carries oxygen from lungs to body tissues.

Heparin: A "blood thinner" or anticoagulant given in hemodialysis to slow clotting time so that blood will not clot in the lines or dialyzer.  

Hepatitis: Inflammation of the liver caused by virus, bacteria, toxic agents or medication.

Hepatitis B Surface Antigen: Substance that indicates infection with hepatitis B. Testing for this antigen is performed frequently on clinic staff and patients.

Hypertension: High blood pressure.

Hypotension: Low blood pressure.


Immunosuppressive Drug: Type of medication that suppresses the body's immune response. Given to transplant recipients to help prevent rejection of the transplanted kidney.

Infection: Invasion of the body by disease-producing organisms and the reaction of the tissues to their presence.

Inflammation: Localized heat, redness, swelling and pain; usually as a result of infection or irritation.

Intravenous: Within a vein.


Kt/V: Clearance "X" time/volume. Measure that indicates how well waste products have been removed by dialysis treatment.

Kidneys: Two bean-shaped organs located at the back of the abdominal cavity, one on each side of the spinal column. Kidneys maintain the body's chemical balance by excreting waste products and excess fluid in the form of urine.

Kilogram: 1,000 grams; 1 kilogram equals 2.2 pounds.


Liter: The basic unit of volume measurement in metric system, approximately equal to quart.


Membrane: Thin layer of tissue or material, usually an outer layer or lining of organs or group of organs.

Metabolism: Physical and chemical changes occurring within the body in order to produce and use energy.

Minerals: Inorganic substances necessary to normal body function, but toxic in high concentrations.

Monitor: (noun) Electronic device used to check, remind or warn. (verb) Watching patients during their treatments, or checking the adequacy of treatments over time.


Nausea: Upset stomach.

Nephrectomy: Surgical removal of the kidney.

Nephrologist: Doctor specializing in kidney disorders.

Nephron: Unit of the kidney which maintains the body's chemical balance. There are approximately one million nephrons in each kidney.

Neuropathy: Any disease of the nerves.


Osmosis: Movement of fluid through a semipermeable membrane to achieve equal concentration on both sides of the membrane.

Overheat: Make or become too hot.

Palpitation: Irregular beating of the heart.

Parathyroid Glands: Small glands located in the neck that produce a hormone which regulates calcium and phosphorus levels in the blood.

Parathyroidectomy: Surgical removal of the parathyroid glands. Can be partial or complete.

Pericarditis: Inflammation of the pericardium, the sac-like structure surrounding the heart.

PD Plus: A combination of CCPD and CAPD mostly used by PD patients who need more efficient dialysis.

Peritoneal Cavity: Space surrounding the abdominal organs located under the abdominal muscles.

Peritoneal Dialysis: A form of dialysis in which the lining of the abdomen, the peritoneal membrane, acts as a natural filter.

Peritoneum (or Peritoneal Membrane): Smooth, semipermeable membrane that covers the abdominal organs and lines the abdominal cavity.

Peritonitis: Infection of the peritoneal cavity that must be treated immediately by a doctor.

Phosphate Binders: Medications that bind with dietary phosphorus so that it may be eliminated from the body; helps keep calcium and phosphorus in balance for dialysis patients.

Phosphorus: An element necessary for normal body functions, especially bone formation.

Polycystic Kidney Disease: Hereditary disease involving growth of cysts on kidney tissue.

Potassium: An element needed by the body for normal muscle and nerve function and cell maintenance.

Prophylactic: A medicine or course of action used to prevent disease.

Proteins: Group of nitrogen containing compounds found in the body that are essential to life.

Pruritus: Itching.

Pulse: Throbbing sensation felt in the arteries in time with the heartbeat.

Red Blood Cell: Type of blood cell containing hemoglobin which carries oxygen to the tissues.

Renal: Referring to the kidneys.


Semipermeable Membrane: Material that allows fluids and small particles to flow through but not larger particles.

Sodium: Element found in the body that helps regulate the body's fluid content.

Sterile: Totally Free from any living microorganisms.


Thrill: Pulsation (vibration or buzzing) felt over the graft or fistula.

Tissue Typing: Matching the blood cells of potential transplant recipients with donors.

Toxin: Waste product in the blood or any substance that is poisonous.


URR: Urea reduction ratio. Percentage based on how much blood urea nitrogen (BUN) was removed during a dialysis treatment. Indicates how effectively urea and other waste products have been removed.

Ultrafiltration: Process used to remove excess fluid from the blood during dialysis.

Urea: Nitrogenous waste product formed during the breakdown of protein in the body.

Uremia: Buildup of waste products in the blood due to the inability of the kidneys to excrete them.


Vascular: Pertaining to blood vessels.

Vein: Blood vessel that carries blood from other parts of the body back to the heart.

Venous: Referring to veins and the flow of blood to the heart.

Venous Line: Tube that carries blood from the dialyzer back to the body.


Waste Products: Substances formed from the breakdown of protein in foods and from normal muscle activity.

White Blood Cell: Type of blood cell that fights infection in the body.

Recommended Reading:

The 5 Stages Of Kidney Disease: Kidney Disease is described as having five stages (Stage 1 to Stage 5) based on the percentage of kidney function remaining. Determine your stage and how to prevent further progression.

Success Tips: These tips will reduce the risks of  hospitalization and will generally improve your overall quality of life by addressing head on those issues that may worry you,  mistakes that are  commonly made, and misconceptions frequently held.

End Stage Renal Disease (ESRD) Treatment Alternatives: Over 275,000 Americans rely on dialysis to live,  and nearly twice that number receive therapy for ESRD. Find out what treatment plan works best for your lifestyle.

Monitoring Lab Results: Blood tests are taken routinely on a monthly basis, and though they may vary slightly from one lab to another, note the standard ranges for key tests. Identify strategies to manage test results and maintain a higher level of energy and health.

Kidney Community Resources: These organizations service the Kidney Community.