CMS SOM App. H, Tag V253

7.2 Microbial monitoring methods

7.2.1 General: Dialysate (dialysate sampling frequency)

Culture … dialysis fluid weekly for new systems until a pattern has been established. For

established systems, culture monthly unless a greater frequency is dictated by historical

data at a given institution.

Samples of water should be collected from several places to give an indication of the microbial

quality of the water throughout the water distribution system. In general, samples should be

collected in the following areas: from the first and last outlets of the water distribution loop,

where water enters equipment used to reprocess dialyzers, and where water enters equipment

used to prepare bicarbonate concentrate or from the bicarbonate concentrate mixing tank.

Additional testing, such as at the end of the water purification cascade and at the outlet of the

storage tank, if one is used, may be necessary during initial qualification of a system or when

troubleshooting the cause of contamination within the distribution loop.

Dialysate samples should be collected from at least two machines monthly and from enough

machines so that each machine is tested at least once per year. If testing of any dialysis

machine reveals a level of contamination above the action level, an investigation should be

conducted that includes retesting the offending machine, reviewing compliance with

disinfection and sampling procedures, and evaluating microbiological data for the previous

3 months to look for trends. The medical director also should be notified. An example of a

decision tree for this process is given in Figure 1.

7.2.2 Sample collection

Dialysate samples should be collected from a dialysate port of the dialyzer… [or] dialysate

sampling ports that can be accessed using a syringe. At least 25 mL of fluid, or the volume

specified by the laboratory performing the test, should be collected in sterile endotoxin-free

specimen containers.

Interpretive Guidance § 494.40(a)

Page 107 of 420

ANSI/AAMI RD52:2004

7.2.2 Sample collection

In some newer dialysis machines, dialysate flow stops when the effluent line is disconnected from

the port. In these instances, the machines are equipped with dialysate sampling ports that can be

accessed using a syringe. These sample ports may be disinfected with alcohol and allowed to air

dry. A 30 mL sterile syringe should then be used to aspirate dialysate out of and into the port

before filling the syringe. The filled syringe should be discarded, and a fresh sample of dialysate

collected using a new sterile syringe.

Additional Guidance:

Facilities may take samples of dialysate using a “clean catch” technique of the effluent from the

Hansen connectors into sterile endotoxin-free collection containers, use a needleless system to

access the port on the dialysate line, or use a syringe and needle to aspirate a sample from the

port on the dialysate line.

A flow chart which gives suggestions for evaluating dialysate culture results and initiating

corrective actions can be found in the original AAMI RD52:2004 document at Figure 1.