The paper is based on a bachelor thesis dealing with the amount of blood aspirated before sampling from the central venous catheter. To accomplish this clinical study, I was led by the fact that there are no uniform standards in the Czech Republic for the number of aspiration before sampling.
I also paid attention to the effects of potassium on the human body, the laboratory method of blood potassium level testing, and possible mistakes made during collection. I also dealt with a detailed description of the structure of the central venous catheters and, in particular, their volume.
The work includes results that were evaluated after a clinical study of 30 patients with established central venous catheter.