Methemoglobinemia in critically ill patients during extended hemodialysis and simultaneous disinfection of the hospital water supply.
BACKGROUND
To evaluate the cause of methemoglobinemia in patients undergoing extended daily hemodialysis/hemodiafiltration we analyzed the relationship between methemoglobinemia and the water disinfection schedule of the hospital.


METHODS
We reviewed all arterial blood gas analyses, obtained over a one-year period, in patients undergoing extended hemodialysis/hemodiafiltration, and compared the methemoglobin concentrations obtained on the days when the water supply was disinfected, using a hydrogen peroxide/silver ion preparation, with data measured on disinfection-free days.


RESULTS
The evaluation of 706 measurements revealed a maximum methemoglobin fraction of 1.0 (0.8; 1.2) % (median and 25th; 75th percentiles) during hemodialysis/hemodiafiltration on the disinfection-free days. The methemoglobin fraction increased to 5.9 (1.3; 8.4) % with a maximal value of 12.2% on the days of water disinfection (P < 0.001 compared to disinfection-free days). Spot checks on hydrogen peroxide concentrations in the water supply, the permeate, and the dialysate, using a semi-quantitative test, demonstrated levels between 10 and 25 mg/l during water disinfection.


CONCLUSIONS
Our results demonstrate that even a regular hospital water disinfection technique can be associated with significant methemoglobinemia during extended hemodialysis. Clinicians should be aware of this potential hazard.
Bek
Martin Johannes
MJ
Dialysis Centre Bad Krozingen, Heart Centre Bad Krozingen, Suedring 15, 79189 Bad Krozingen, Germany. Bek.Martin@web.de.
Laule
Sven
S
Reichert-Jünger
Christine
C
Holtkamp
Rainer
R
Wiesner
Michael
M
Keyl
Cornelius
C
D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis; D016638:Critical Illness; D004203:Disinfection / Q000379:methods*; D005260:Female; D006761:Hospitals; D006801:Humans; D006861:Hydrogen Peroxide; D008297:Male; D008706:Methemoglobin / Q000032:analysis / Q000096:biosynthesis*; D008708:Methemoglobinemia / Q000175:diagnosis / Q000209:etiology*; D008875:Middle Aged; D006435:Renal Dialysis; D012189:Retrospective Studies; D018030:Silver Compounds; D013997:Time Factors; D014871:Water Microbiology / Q000592:standards; D014881:Water Supply / Q000592:standards*
D018030:Silver Compounds; D008706:Methemoglobin; D006861:Hydrogen Peroxide