CCHT Water Treatment and Quality 3

Question 1

A dialysis patient develops aluminum toxicity. Which water treatment failure is the most likely cause?

Accepted Answer

Inadequate removal of aluminum from the source water by the RO system

Answer

Aluminum toxicity in dialysis patients is primarily caused by inadequate removal of aluminum from source water, which then enters the patient's bloodstream via the dialysate. The RO system must effectively remove aluminum; failure of the RO or elevated source water aluminum can cause toxic accumulation.

Question 2

What is the purpose of testing dialysis water for endotoxins?

Accepted Answer

To detect bacterial cell wall fragments that can cause inflammatory reactions even in the absence of live bacteria

Answer

Endotoxins are lipopolysaccharides derived from gram-negative bacterial cell walls. Even dead bacteria release endotoxins. When endotoxins enter the bloodstream via the dialysate, they trigger immune responses causing fever, hypotension, and systemic inflammation—even without live bacterial infection.

Question 3

During a water quality check, the RO product water conductivity reading is 45 μS/cm, significantly higher than the baseline of 8 μS/cm. What does this most likely indicate?

Accepted Answer

The RO membrane is failing or bypassed, allowing solutes to pass through into the product water

Answer

A sudden increase in RO product water conductivity from 8 to 45 μS/cm (nearly 6-fold increase) indicates that the RO membrane is no longer effectively rejecting dissolved solutes. This is a significant quality failure requiring immediate investigation and potentially halting patient treatments until resolved.

Question 4

What is the function of the distribution loop in the dialysis water treatment system?

Accepted Answer

To continuously circulate RO-purified water to dialysis machines, preventing stagnation and bacterial growth in supply lines

Answer

The distribution loop continuously circulates RO product water through the supply lines to all dialysis machines. Continuous circulation prevents water from becoming stagnant in the lines, which would allow bacterial biofilm to form and multiply in the piping system.

Question 5

What type of water quality testing documents are required to be maintained in the dialysis facility?

Accepted Answer

Daily chlorine/chloramine logs, monthly bacteriology and endotoxin results, and annual chemical analysis, retained for at least 2 years

Answer

Facilities must maintain comprehensive water quality records including daily chlorine/chloramine logs, monthly microbiological results (bacteria and endotoxins), and annual chemical analysis for all AAMI-required contaminants. CMS Conditions for Coverage require these records to be retained and available for surveyor review.

CCHT - Certified Clinical Hemodialysis Technician Practice Test

CCHT - Certified Clinical Hemodialysis Technician Practice Test

CCHT Water Treatment and Quality 3