Potential preanalytical errors in whole-blood analysis: Effect of syringe sample volume on blood gas, electrolyte and lactate values

Abstract

Background: Arterial blood samples are sensitive to bias because of the physiological properties of blood. Several errors can occur in the preanalytical phase leading to incorrect diagnosis and improper treatment of patients. Collection of a blood specimen, as well as its handling and transport, belong to the key factors to affect the accuracy and good quality of clinical laboratory analysis. Methods: The aim of this study was to validate the effect of different sample volumes on the blood gas, electrolyte and lactate values using 3mL Rapidlyte plastic syringes with filter cap and Rapidlab 865 blood gas analyser. Also, the stability of blood gas analyser parameters with different sample volume was studied. Results: No substantial change in blood gas, electrolyte and lactate parameters was found when the results of 3mL, 1.8mL sample volumes in the 3mL syringes were compared. The sample volume of 1.0mL or 1.5mL in the 3mL syringe is not suitable for the measurement of oxygen tension, especially when accurate results of pO₂ and arterial blood is needed for patient's diagnosis. Conclusions: The minimum sample volume when blood gases, electrolytes and lactate are all measured with the Rapidlab system should be 1.8mL using 3mL Rapidlyte plastic syringe with filtercap. According to this study <1.8mL sample volumes can provide inaccurate results and can impose biases on measurements.

Keywords::

• Blood gas analyzer
• preanalytical
• sample volume
• syringe
• whole-blood analysis

Acknowledgements

In memoriam: We owe this study and our warmest thanks to Dr Päivi Kaukoranta for her invaluable collaboration during this work.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Abbreviations:

CLSI: Clinical and Laboratory Standards Institute; NCCLS: National Committee for Clinical Laboratory Standards.