Nutritional requirements are difficult to predict in mechanically ventilated patients because of their disease processes, inflammatory responses, and other variables. At the same time, proper nutrition support and its careful monitoring are vital to optimal outcomes. This monitoring requires the expertise of both respiratory therapy and nutritional support teams. It is best accomplished with indirect calorimetry (IC), which measures oxygen consumption and carbon dioxide production to assess energy expenditure and so determine nutritional needs.
IC is preferred over estimations (predictive equations) whenever measuring patients is feasible. An understanding of the variables and potential confounders involved in IC is critical in assessing and interpreting its results. Three articles in the Critical Decisions publication examine IC from both respiratory therapy and nutrition support perspectives. They offer a comprehensive, interdisciplinary view of how the collective expertise of these groups and intensive care teams can use IC to patients’ greatest advantage. The articles include practice scenarios and a discussion of various IC technologies.