Final answer:
Hyperglycemia as a PN complication can arise from high glucose levels leading to infections, fever, and dehydration, caused by conditions such as diabetes mellitus and compounded by impaired insulin function and poor glycemic control.
Step-by-step explanation:
The possible causes of hyperglycemia as a complication of Parenteral Nutrition (PN) include infection, fever, and dehydration. High glucose concentrations in PN solutions can foster an environment conducive to microbial growth, leading to infections and delayed wound healing. Moreover, PN solutions containing high glucose can cause imbalances in insulin function, leading to diabetes mellitus, characterized by hyperglycemia. This condition is due to either low insulin production or tissue resistance to insulin, preventing glucose absorption by cells. Over time, uncontrolled high blood glucose levels can result in serious complications such as nerve damage, kidney failure, and cardiovascular disease due to the glycosylation of proteins and blood vessels.