Use of a Screening Procedure for Blood Urea Nitrogen

The results of a paper strip test for blood urea nitrogen were compared with the values obtained by automatic analysis. The short procedure satisfactorily differentiates nor-mal from abnormal levels and can be conveniently used for emergency determinations. CONSTANT PROBLEM lli the hospital climiical laboratory is the emer-gency order which arrives with great regularity after the routine mu of a particular analysis has been finished. With automatiomi the problem has increased, particularly in laboratories where one automatic instrument is used for several different procedures in turii. There are three possible solutions. One is to perforni the test mimanuahly. This requires, gemierally, a second set of standards, comitrol, and reagents, and a more-or-less dif-ferent method for each type of assay from thiat usually perfornied auto-IiiatiCally. Furthermore, these simigle deteriiiinatiomms are highly unpopu-lar with the teehimuical personmiel, who as a consequence often resort to the secOnd solution, which is to reset the automatic instrumentation to run this single determimiatiomi. This is uneconomical for the laborator