Renal Dialysis (Bac 2015 C-D 1er Tour)
Properly functioning kidney tissue is necessary for life. Inadequate function results in the accumulation of waste products in the blood stream, and alteration of the body's chemical balance. This results in a condition called uremia. When uremia is severe and life - threatening, dialysis is generally instituted.
Dialysis involves pumping the patient's arterial blood through a coiled tube of thin cellophane - like material. This coiled tube is immersed in a bath of fluid which closely resembles normal blood plasma. Excess waste products that have accumulated in the patient's blood are washed out through the coil membrane into the surrounding bath, resulting in more normal blood plasma. The dialyzed or washed blood flows from the coil into tubing that leads back to the patient's venous circulation. Some patients are dialyzed on a short-term basis for acute kidney failure such as it may occur in poisonings, shock, burns, severe acute nephritis, or severe injuries.
Other patients require long-term dialysis for chronic renal failure. A patient on chronic renal dialysis usually has a permanent arteriovenous shunt implanted in an arm or a leg to provide ready access to an artery and a vein, both of which are used in the dialyzing procedure. Since the shunts are often external, they may become uncoupled, accidentally or willfully. The patient will then bleed profusely, and may die if the tube is not damped in time.
Adapted from Effective Approaches to Patients' Behavior.
By Gladys B. Lipkin and Roberta G. Cohen, 1973, P. 154
Vocabulary:
coiled tube = tube enroulé,
to clamp = to remove,
a shunt = un conduit, un implant
Guided commentary
- Basing to the text, what is "uremia"? (2 points)
- According to the text, apart from uremia, what are the other cases that may require dialysis? (3 points)
- Referring to the text, when does a person undergo a long-term or short-term dialysis? (4 points)
- Relying on the text, is there any risks for a long-term dialysis? Why or why not? (5 points)
- Are you for or against the use of technological advancements in medicine? Justify your answer. (6 points)