A micro blood sampling system for catheterized neonates and pediatrics in intensive care unit

A new micro blood sampling system has been designed, fabricated, and characterized to reduce iatrogenic blood loss from the catheterized neonates and pediatrics in intensive care unit by providing micro-volume of blood to analytical biomedical microdevices which can do point-of-care testing for their critical care. The system can not only save enormous iatrogenic blood loss through 1 to 10 μL of blood sampling and re-infusion of 1 to 5 mL of discard blood but also reduce the infection risk through the closed structure while satisfying the key criteria of the blood sampler. The sampled blood preserved its quality without rupturing of red blood cells verified by blood potassium concentrations of 3.86 ± 0.07 mM on the sampled blood which is similar to 3.81 ± 0.04 mM measured from the blood which did not go through the system. The sampling volume among the sampling channels showed consistency with the relative standard deviation of 1.41 %. In addition to the micro blood sampling capability, the sampling system showed negligible sample cross-contamination. The analyte-free samples collected after aspirating 7,500 times higher signal sample showed the same output signal as blank. The system was also demonstrated not to cause air-embolism by having no bubble generation during flushing procedure and the system was verified as leak-free since there was no fluid leakage under 30 times higher pressure than central venous pressure for 24 h.