PhD Scientific Days 2025

Conservative Medicine I.

Volumetric Absorptive Microsampling: A Novel Technique for Neonatal Blood Sample Collection for Steroid Measurement

Name of the presenter

Kerekes Ramóna

Institute/workplace of the presenter

Pediatric Center, Semmelweis University

Authors

Kerekes Ramóna¹, Dobi Marianna¹, Zsolnai Hanna¹, Karvaly Gellért Balázs², Farkas Róbert², Csöndör Éva², Méder Ünőke¹, Jermendy Ágnes¹, Szabó Miklós¹, Kovács Kata¹

1: Department of Neonatology, Pediatric Center, Semmelweis University, Budapest, Hungary
2: Department of Laboratory Medicine, Semmelweis University, Budapest, Hungary

Text of the abstract

Introduction: Volumetric absorptive microsampling (VAMS) is an innovative technique that allows for the collection and dried storage of arterial, capillary, and venous blood samples. One of the key advantages of VAMS is its minimal blood volume requirement - only 10 μL per sample. Therefore, the application of VAMS, which has not yet been tested in critically ill neonates, could be highly valuable.
Aims: This study aimed to assess the feasibility of using VAMS and to validate its application for measuring cortisol and cortisone levels in neonates undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy (HIE).
Methods: We conducted a prospective study at Semmelweis University, Budapest, Hungary between November 2023 and January 2025, enrolling neonates with HIE who underwent therapeutic hypothermia. During the hypothermia, we collected capillary blood samples using VAMS (10 μL) and, as a reference, arterial blood samples (200 μL). Cortisol and cortisone concentrations were measured using a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method. The cortisol and cortisone levels were compared with the two sampling methods using Bland–Altman analysis.
Results: We analyzed 75 paired capillary and arterial samples from 23 neonates with HIE. Median arterial cortisol level was 15.3 μg/dL [IQR: 1.8-30.4], and the median arterial cortisone level was 5.7 μg/dL [IQR: 2.0-8,1]. Cortisol levels measured from capillary blood using VAMS were, on average, 2.2 μg/dL lower (95% CI: –15.0 to 10.6 μg/dL), while cortisone levels were, on average, 1.3 μg/dL higher (95% CI: –2.5 to 5.1 μg/dL) compared to reference arterial blood samples.
Conclusions: The average differences between VAMS-derived capillary samples and standard arterial samples appear to be within clinically acceptable limits; however, the variability among individual values is considerable. VAMS may offer significant advantages in critically ill neonates by reducing the required blood volume for laboratory testing. Nonetheless, further data are needed to fully evaluate its accuracy and ensure its reliability for future clinical decision-making.
Funding: OTKA PD 142288; TKP2021-EGA25; National Laboratory of Translational Neuroscience, Recovery and Resilience Facility of the European Union, Programme Széchenyi Plan Plus