FREE CCHT Technical and Environment Test 2

Question 1

The reason potassium dialyzes and RBCs do not is:

Accepted Answer

potassium has a smaller molecular weight

Answer

Dialysis works on the principle of diffusion, where solutes move across a semipermeable membrane. The size of the molecule is a critical factor in this process. Smaller molecules like potassium ions can easily pass through the pores of the dialyzer membrane, while much larger components like red blood cells (RBCs) cannot, ensuring that RBCs remain in the patient's blood.

Question 2

Acceptable limits for total chlorines in water for hemodialysis are?

Accepted Answer

less than 0 .1mg/L (ppm)

Answer

Chlorine and chloramines are highly toxic to hemodialysis patients, as they can cause hemolysis (destruction of red blood cells) if present in the dialysate. Therefore, strict standards are in place for water quality used in hemodialysis. The acceptable limit for total chlorines (chlorine and chloramines) in water for hemodialysis is extremely low, typically less than 0.1 mg/L (parts per million), to ensure patient safety.

Question 3

The following are factors in poor clearance during dialysis except:

Accepted Answer

low hematocrit

Answer

Poor clearance during dialysis refers to the ineffective removal of waste products. Factors like poor dialyzer reuse (reduced efficiency), access recirculation (dialyzed blood re-entering the access), and low blood flow rate (less blood exposed to the dialyzer) directly impair the dialysis process. Low hematocrit, while indicating anemia, does not directly affect the dialyzer's ability to clear solutes from the plasma portion of the blood.

Question 4

The movement of water from an area of low solute concentration to an area of high solute concentration is called:

Accepted Answer

osmosis

Answer

Osmosis is the passive movement of water (solvent) across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. This movement occurs to equalize the solute concentrations on both sides of the membrane. In dialysis, osmosis plays a role in fluid shifts, although ultrafiltration is the primary mechanism for controlled fluid removal.

Question 5

Potting compound, casing, fibers, and headers are part of a:

Accepted Answer

dialyzer

Answer

A dialyzer, often referred to as an 'artificial kidney,' is the core component of the hemodialysis system where blood purification occurs. It consists of a casing that encloses thousands of hollow fibers (the semipermeable membrane), which are sealed at each end by potting compound and held in place by headers. Blood flows through these fibers, and dialysate flows around them, facilitating the exchange of wastes and fluids.

CCHT - Certified Clinical Hemodialysis Technician Practice Test

CCHT - Certified Clinical Hemodialysis Technician Practice Test

FREE CCHT Technical and Environment Test 2