Final aqueous formaldehyde concentration delivered to the dialyzer should be 4
percent and allowed to dwell in the dialyzer for 24 hours at a temperature of at
least 20 degrees C. Lower concentrations of formaldehyde can be used at higher
temperatures if validated as effective. Peracetic acid (PAA) based solutions for
dialyzer reprocessing (Micro-X, Renalin, or Peracidin) should be an unexpired 3 -
3.5 percent solution allowed to dwell in the dialyzer for 11 hours at room temperature.
PAA solutions should not be heated. Mix germicide solutions thoroughly.
Do not rely on the flow force of the dilution water to mix germicides. Ovens used
for heat disinfection (or heating dialyzers filled with formaldehyde) must be
checked periodically to verify temperature controls are working properly.
Consider quantitative testing for the presence of formaldehyde/glutaraldehydes
instead of dyes. Do not put dye in PAA solutions. If you are using a manual
system, make sure volume of blood compartment and dialysate compartment are
both exchanged at least 3 times with germicide before capping for storage.
Consider using ultrafiltration of final germicide when manually reprocessing high
flux dialyzers (see procedure at end of rationale section). Your dialyzer filling
procedure must guarantee that blood and dialysate side final germicide concentrations
are at least 90 percent of the prescribed concentration.