A first node of a patient care device processes data relating to the patient care device and sets a public variable equal to a value of the data. A second node receives the public variable from the first node, sets a private variable equal to the value of the public variable, and executes a software program that reads the private variable but not the public variable. In other embodiments, the second node checks to see if the public variable is registered at the second node, and if so, uses the private variable in carrying out a function. The first node executes a first software program that sets the public variable to the value and relies on a service to share the value with the second node. The sharing occurs despite the first software program not containing any instructions for transmitting the value or variable to the second node.