Low Diagnostic Utility of Rechecking Hemoglobins Within 24 Hours in Hospitalized Patients

Am J Med. 2016 Nov;129(11):1194-1197. doi: 10.1016/j.amjmed.2016.07.004. Epub 2016 Jul 22.

Abstract

Background: Clinicians often repeat hemoglobin tests within a 24 hour period to detect or monitor anemia. We sought to determine the percentage of hemoglobin tests repeated within a single hospital day that were at least 1.0 g/dL lower than the first test.

Methods: We performed a retrospective cross-sectional analysis of hospitalized adults on medical or surgical services over 1 year at a single academic hospital. Using patient and laboratory data in the electronic health record, we analyzed the proportion of repeated hemoglobin test results that were at least 1 g/dL less than the initial hemoglobin value of that day, excluding days when transfusions were administered.

Results: A total of 88,722 hemoglobin tests were obtained from 12,877 unique patients, who contributed a total of 86,859 hospitalization days. In 12,230 (14.1%) of those days, 2 or more hemoglobin tests were obtained within a single day. In the 6969 days with 2 hemoglobin tests obtained and no transfusions given, 949 (13.5%) were ≥1 g/dL lower than the initial hemoglobin value of that day, and 260 (3.7%) were ≥2 g/dL lower. Repeated tests did not often reach transfusion thresholds: 482 (6.9%) of repeat hemoglobin values were <8 g/dL, and 64 (0.9%) were <7 g/dL.

Conclusions: Hemoglobin tests were repeated in 14% of hospital days. For patients who had 2 hemoglobin tests obtained on the same day, 13.5% demonstrated a clinically significant drop. This information may be helpful to clinicians when considering whether repeat testing is appropriate.

Keywords: Anemia; High-value care; Laboratory testing; Overuse.

MeSH terms

  • Aged
  • Anemia / diagnosis
  • Anemia / metabolism*
  • Anemia / therapy
  • Cross-Sectional Studies
  • Erythrocyte Transfusion
  • Female
  • Hemoglobins / metabolism*
  • Hospitalization
  • Humans
  • Male
  • Medical Overuse
  • Middle Aged
  • Retrospective Studies
  • Time Factors

Substances

  • Hemoglobins