345 - The Validity of Point-of-care Hemoglobin Measurements in Neonates

Poster Number: 345
Publication Number: 345.122

Anitha F. Ahmed, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; John Wang, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; Rangasamy Ramanathan, Keck School of Medicine of USC, Los Angeles, CA, United States; Amy Yeh, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States

Background: Neonates admitted to the neonatal intensive care unit (NICU) are at risk of iatrogenic anemia due to need for repeated blood draws. Low hemoglobin (Hb) is an independent risk factor for mortality among neonates, and long-term anemia can affect growth and development. Hb measured by way of point-of-care (POC) or blood gas analyzers, which each require 1-2 drops of blood per test, could limit phlebotomy as compared to the Complete Blood Count (CBC), which requires 0.6 to 1 milliliter, thus helping prevent iatrogenic anemia.

Objective: This study aims to determine the validity of POC and blood gas Hb as compared to CBC Hb.

Design/Methods: This is a retrospective study of neonates admitted to the LAC+USC Medical Center NICU between January 2020 and April 2021 with paired Hb measurements from the CBC and either POC meter HemoCue B 201 or blood gas analyzer Gem Premier 5000. Qualifying data was divided into groups based on time between different blood draws, the first comprising of measurements collected within 12 hours of each other, the second collected between 12 and 24 hours of each other. T-tests were used for analysis of continuous, normally distributed variables. Regression analysis was performed to determine the relationship between paired Hb values. Bland-Altman analysis was performed to evaluate for bias between mean differences. Statistical significance was set at p< 0.05.

Results: There were 488 paired CBC and blood gas Hb samples in the < 12 hour group, and 243 paired samples in the 12-24 hour group. There were 479 paired CBC and POC Hb samples in the < 12 hour group, and 290 paired samples in the 12-24 hour group (Table 1). Correlation coefficient (r) for the CBC-POC Hb groups was 0.87 in the < 12 hour group and the mean difference is -0.4 (95% confidence interval, CI=-3.18-2.38) and 0.75 in the 12-24 hour group and the mean difference is -0.1 (CI=-3.58-3.37) (Figure 1). Correlation coefficient for the CBC-blood gas Hb groups was 0.89 in the < 12 hour group and the mean difference is 0.68 (CI=-2.04-3.39). and 0.83 in the 12-24 hour group and the mean difference is 0.62 (CI=-2.43-3.66) (Figure 2).Conclusion(s): There was a strong correlation between paired POC or blood gas and CBC Hb values obtained within 12 hours of one another. Our results show that POC Hb or blood gas Hb could be considered as alternatives for CBC Hb which would help prevent iatrogenic anemia in the NICU. Prospective studies with age- or weight-based grouping and planned pairing within pre-defined time periods would be beneficial in determining whether the correlation persists between POC and CBC Hb measurements in the NICU.
Anitha Ahmed Curriculum VitaeAhmed Anitha CV Jan 2022.pdf
Figure 1Correlation Between Paired CBC Hb and POC Hb Measurements