Parenteral nutrition represents a well-established but highly sensitive process associated with several patient conditions. It typically involves assessments of many parameters and a wide range of observations in order to come up with the best possible parenteral solution for a patient. Different calculation tables are used to determine correct ratios of nutritional elements which would later be administered. This work focuses on providing a process map for parenteral nutrition in children using the combination of Petri nets and openEHR methodology to create an overview for the decision-making process.