[49501611]
Our alfa wasserman ace axcel chemical analyzer has demonstrated instability during testing of serum electrolyte levels. This has resulted in erroneous serum chloride, sodium and potassium levels. The problem has been most pronounced with the chloride levels. This issue has been discussed in great detail with the manufacturer, however they could offer no solution to the problem. Review of the problem within our laboratory seems to indicate either a reagent stability problem or an ion selective electrode (ise) problem. During our internal analysis of this issue, we noted that the temperature within the instrument in the area of the internal reagent storage and the ise location was substantially warmer than the ambient temperature (i. E. Room temperature). A one-week analysis performed by obtaining hourly temperature readings both of the ambient and internal temperatures using nist-traceable thermometers showed an average elevation of temperature of 7. 1 degrees celsius inside the unit. Currently, we are showing stability of the reagents once placed into the machine of approximately one week, while the labeling of the package indicates that the reagents should be stable for several months to a year. Also, the reagent labeling indicates that the reagents should be stored at no higher than 26 degrees celsius, while we are reading internal temps at 29 - 31 degrees celsius. Discussion with another lab using the same model of analyzer confirms the same internal temperature elevation and reagent instability problems. Note that all other reagents in this analyzer are kept in a temperature-controlled internal area, but that the ise reagents are not maintained in a temperature-controlled area. The manufacturer did indicate to us that a component of the analyzer which generates a large proportion of the heat from the unit is located adjacent to the ise reagent storage area. My concern is that this markedly elevated internal temperature is creating rapid degradation of the ise reagents, and that this is leading to erroneous electrolyte testing results. This appears to be due to a design flaw with this chemical analyzer. Copies of our testing data as discussed above are available from this laboratory on request.
Patient Sequence No: 1, Text Type: D, B5