This study was performed to evaluate the clinical utility of blood smear analysis by emergency room personnel (ERP). The efficacy of ERP blood smear evaluation was compared with automated or manual evaluation by veterinary clinical pathology staff and personnel in 155 blood smears from cats (n = 16) and dogs (n = 139) presented at Tufts Cummings School of Veterinary Medicine (TCSVM) between September 2008 and July 2009. ERP included emergency/critical care residents (53), interns (50), or veterinary students (52). In addition to estimated white blood cell and platelet counts, estimates of the number of smears interpreted weekly by each reader, erythrocyte/leukocyte morphology, and any other abnormalities were noted on a standardized form. The point-of-care assessments were compared with the TCSVM clinical laboratory results. Slides demonstrating cellular abnormalities underwent further direct evaluation by a clinical pathologist. Poor agreement was noted between ERP-estimated and TCSVM automated white blood cell counts. Moderate agreement was noted for platelet counts. Furthermore, abnormal clinical pathologic findings were inconsistently identified on ERP slides.

Commentary: These results suggest that one cannot rely solely on blood smear analysis in the emergency situation for clinical diagnosis, as results may not be as accurate as those of clinical pathology laboratories. However, the importance of early diagnosis and management, particularly in emergencies involving hematologic derangements, cannot be overemphasized. Future studies should evaluate the performance of estimates by ERP as well as by benchtop point-of-care analyzers to better characterize their accuracy. Lastly, it may be beneficial to create modules in emergency hematologic analysis for ERP as reference materials to enhance patient care.—Indu Mani, DVM, DSc

Interpretation of canine and feline blood smears by emergency room personnel. Lanaux TM, Rozanski EA, Simoni RS, et al. VET CLIN PATHOL 40:18-23, 2011.