Michigan Dialysis Services

A UM clinical partnership with Renal Research Institute
Patient Education


As you move through the process of treating your disease, you may come across terms you’re not familiar with. Feel free to ask your Michigan Dialysis Services kidney care team for help, or scroll through the following glossary, developed by the DPC Education Center.


Access: In dialysis, the natural or artificial blood vessel used to get blood in and out of the dialysis filter.
Adverse reaction: An unexpected and undesirable reaction to a drug or treatment that may be serious or life threatening.
Anticoagulation: The process of administering a substance, such as heparin, to prevent the blood from clotting.
Artery: Blood vessels that carry blood away from the heart.
Arteriovenous fistula: Also called an AV fistula. A surgical connection of an artery directly to a vein, usually in the forearm, created in patients who will need hemodialysis.
Arteriogram: An X-ray of the arteries taken with the use of a contrast dye; sometimes called angiography.
Artificial kidney: Another name for a dialysis filter or dialyzer.
Aseptic technique: Practices that reduce the risk of infections.


Bacteria: Single-cell organisms or “germs” that can cause infection or disease.
Bloodborne pathogens: Organisms or “germs” that can live in the blood and can be spread to other people.
Blood flow rate (BFR): The volume of blood per minute flowing from and returning to the patient through the blood tubing and filter. Blood flow rate is measured in ml/min.
Bloodline: The tubing set that carry the blood from the patient to the hemodialysis machine and back to the patient.
Blood pressure: The force of blood exerted on the inside walls of blood vessels, expressed as a ratio (example: 120/80, read as “120 over 80”).
Bolus: Giving a specific amount of intravenous fluid during dialysis. This is usually used to treat low blood pressure.


Catheter: A soft tube that is inserted into a large vein in the neck, chest or leg to provide vascular access.
Chronic kidney disease (CKD): Damage of the kidneys from a variety of causes.
Convection: A process in which waste products are carried across a membrane or filter by the movement of fluid. This works kind of like a coffee maker.


Dehydration: The loss of too much body fluid through excessive urinating, sweating, diarrhea or vomiting.
Dialysis: The process of artificially removing wastes and excess fluid from the blood.
Dialysate: A special fluid mixture used to clean the blood during dialysis.
Dialyzer: The filter used in a dialysis system to remove wastes and fluid.
Diastolic blood pressure: The “bottom” number in a blood pressure reading (120/80), or the blood pressure when the heart rests.
Diffusion: Movement of waste products across a membrane or filter from a high concentration (the blood) to a low concentration (dialysate). This works kind of like making tea with a tea bag.
Disinfection: The process of cleaning to prevent the growth of bacteria that could lead to infection.
Dry weight: The “ideal” weight for a person, at which blood pressure is normal and there is no swelling from extra fluid.
Dwell time: The amount of time dialysis solution remains in the patient’s abdominal cavity during a peritoneal dialysis exchange.


Edema: Swelling caused by excess fluid and salt in the body.
Effluent: The filtered fluid containing waste products and excess fluid removed from the patient’s blood.
Electrolytes: Chemicals in body fluids including sodium, potassium, magnesium and chloride.
End-stage kidney disease: Total and permanent kidney failure.
Erythropoietin: A hormone made by the kidneys that stimulates the body to make red blood cells.


Filter: See dialyzer.
Fistula: A connection created by surgery between an artery and a vein to make a bigger blood vessel for dialysis access. Considered the “gold standard” because it is easy to use, has low infection rates and lasts a long time.
Fluid overload: A condition in which the body contains too much water and salt.


Graft: In hemodialysis, a vascular access surgically created using a synthetic tube to connect an artery to a vein.


Hemodialysis: The process of using of a machine to remove wastes and fluid from the blood after the kidneys have failed.
Hypertension: High blood pressure.
Hypertensive: Having high blood pressure.
Hypotension: Low blood pressure.


Kidney: One of two bean-shaped organs that filter wastes from the blood; located near the middle of the back.
Kidney failure: Loss of kidney function.


Membrane: A thin sheet or layer of tissue that lines a cavity or separates two parts of the body, and that can act as a filter.
Modality: A type of treatment.


Nephrology: A branch of medicine that focuses on the kidneys. A nephrologist is a physician who specializes in diseases of the kidney.
Nocturnal: Happening at night; in dialysis, this is treatment that is done at night while the patient is sleeping.


Oxalate: A chemical that combines with calcium in urine to form the most common type of kidney stone (calcium oxalate stone).
Over-the-counter: Medications that can be sold and obtained legally without a doctor’s prescription.


PCT: A patient care technician who helps nurses deliver dialysis treatments in the clinic.
Peer mentor: A person who is or has gone through dialysis and can offer support from the patient’s point of view.
Phosphate: A substance in many types of foods.
Phosphate binders: Medication that helps prevent a build-up of phosphate in the blood.
Prescription: A doctor’s written orders; can be for medicines or treatments like dialysis.


Renal: Having to do with the kidneys.
Rinse back: Using sterile fluid to rinse the bloodline and dialyzer of all blood after dialysis.


Semipermeable membrane: A natural or artificial membrane that aids in the separation of substances and fluids, and allows only certain types of substances to move across it.
Stenosis: A narrowing of a blood vessel or other organ.
Systolic blood pressure: The first number of a blood pressure (120/80), or the pressure when the heart pushes blood out into the arteries.
Support group: An organized network of people with a disease in common who give and receive help, advice, friendship and emotional support.


Toxin: Something that is poisonous.


Ultrafiltration: A process that removes fluid from the blood; if not replaced, it reduces excess patient weight.
Ultrafiltration rate: The amount of fluid, measured in liters or milliliters per hour, removed from a patient across a filter to reach a dry weight goal.
Universal precautions: A way of preventing infection by treating all blood and body fluids as if they contained infection. See aseptic technique.


Vaccine: A serum containing weakened or killed germs that protect against infections.
Vascular access: A natural or artificial blood vessel used to move blood into and out of a dialysis filter.
Vein: A blood vessel that carries blood toward the heart.