EVALUATION OF QBC(R)-AUTOREAD PERFORMANCE IN AN EMERGENCY DEPARTMENT SETTING

The objective of the study was to examine the accuracy and clinical ut ility of technology using a quantitative buffy coat analysis in determ ining complete blood cell count results in an emergency department. A prospective observational study was done at an urban pediatric emergen cy department. One hundred ninety-one patients who had a complete bloo d cell count (CBC) ordered by the managing emergency physician from 11 AM to 3 AM participated. A blood analysis was performed in the emerge ncy department on the QBC(R) Autoread System for hemoglobin (Hgb), hem atocrit (Hct), white blood cell count (WBC), absolute and percent gran ulocytes (Gr), absolute and percent lymphocytes/monocytes (L/M), and p latelets (PTLS). Results were compared with a CBC analysis on the hosp ital laboratory system (Coulter S-8-80(R)). Time from specimen collect ion to results were compared for QBC(R) and laboratory CBC. Emergency physicians completed a clinical utility survey after reviewing QBC(R) results. Linear regression curves revealed a high correlation between the two methods for all parameters studied (Hgb: R = 0.911, Hct: R = 0 .868, natural log WBC: R = 0.938, % Gr: R = 0.932, % L/M: R = 0.939, a nd natural log PTLS: R = 0.877). The mean time for collection to QBC(R ) result was 17.3 +/- 11.6 minutes compared with 42.2 +/- 17.9 minutes for collection to CBC result. One hundred thirty-five clinical utilit y forms were completed by the managing physicians after a review of th eir patient's QBC(R) result. In 20% of cases, physicians felt the QBC( R) result would have shortened the patient's length of stay in the eme rgency department, and in 85% they felt the result confirmed their cli nical impression. Fifty-seven percent of physicians felt the results w ere critical (4%) or helpful (53%) in patient management. We concluded that the QBC(R) Autoread System is accurate compared with standard la boratory CBC analysis for routine hematology parameters including Hgb, Hct, WBC, % Gr, % L/M, and PTLS. Disposition time may be shortened fo r some emergency department patients. Other diagnostic tests or proced ures may negate any time saved by obtaining a QBC(R) analysis in high- acuity patients.