Point-of-Care Testing of White Blood Cell Count and C-Reactive Protein in a Pediatric Emergency Department

Date of submission: 14-10-2019 | Date of acceptance: 22-06-2020 | Published: 02-10-2020

Abstract

Introduction: Laboratory workup is often required to assess patients admitted to the Pediatric Emergency Department. Among bloodwork, white blood cell count (WBC) and C-reactive protein (CRP) are commonly screened markers. Only a few studies about point-of-care (POC) tests performance in a pediatric clinical setting have been reported. The main goal of the study was to compare the accuracy and clinical applicability of POC tests for WBC and CRP with conventional testing methods. We also assessed patient discomfort and hands-on time for both procedures.

Methods: Patients were included based on clinical criteria for blood sampling. For each patient, capillary blood samples for POC tests and venous blood samples for conventional analysis were collected to measure WBC and CRP. Pain was assessed with age appropriate scales and both procedures were timed. Statistical analysis was performed using MedCalc^® version 15.8. Agreement between sample collections was analyzed with Bland-Altman plot.

Results: A total of 242 blood samples sets were obtained. POC test showed good agreement with the conventional method in all assessed parameters. The mean differences between POC and conventional test were 0,9 x 10³/μL for WBC and -0,2 mg/dL for CRP. The error rate of POC test was 5% for CRP and 17% for WBC. The pain score and hands-on time for sampling were lower in the capillary puncture (p < 0,001).

Discussion: POC tests were considered accurate. Overall, capillary blood sampling was less painful and time-consuming than venipuncture. POC testing can be a useful tool to improve the management of patients in a Pediatric Emergency Department.