Prototype and evaluation of automatic fingertip-blood-sampling system that uses fingertip blood-vessel images to determine puncture position.

We are developing an automatic fingertip-blood-sampling system to reduce the burden on trained medical personnel. For this system to withdraw a consistent volume of sampled blood for blood tests, we developed a mechanism for our system to select and puncture the vicinity of a large blood vessel from the blood-vessel image of an individual's fingertip. We call this mechanism the fingertip-vessel-puncture mechanism. From the results of an experiment in which the fingertips of 20 individuals (men and women in their 20 s to 60 s) were manually punctured at near and far locations from the blood vessel selected with our mechanism, the following conclusions were obtained. The fingertip-vessel-puncture mechanism tends to increase the volume of sampled blood, thus is effective in sampling more than 650 µL of blood for automatic blood analyzers. It was also found that it is more effective in increasing the volume of sampled blood in the men and those who were younger.

Evaluation of cardiac assays on a benchtop chemiluminescent enzyme immunoassay analyzer, PATHFAST.

Devices for cardiac immunoassay are widely available at point of care settings. The lateral flow method is the most popular solution for ease of use. But its major shortcomings, poor assay precision, and low analytical sensitivity may lead to false negative results. Therefore, confirmatory testing by a routine lab analyzer sometimes is necessary. In the current study, we evaluated the cardiac assays troponin I, MB isoenzyme of creatine kinase, myoglobin, and N-terminal pro brain natriuretic peptide on a chemiluminescent enzyme immunoassay analyzer, PATHFAST. All of the assays demonstrated correlation coefficients higher than 0.97 against the predicate devices along with good total precision (coefficients of variation <10%), and the troponin I assay showed analytical sensitivity in conformance with the guidelines of European Society of Cardiology/American College of Cardiology and National Academy of Clinical Biochemistry. We concluded that the system was rapid and easy to use without compromising analytical performance.