Energy needs in adult critically ill patients with infection.

Indirect calorimetry is the gold standard in the determination of energy needs of critically ill patients. Current practice is to use less accurate estimations of energy requirements using predictive methods which are quicker and lower cost. There is minimal data on energy needs during the course of ICU admission in critically ill patients with infection and the feasibility of indirect calorimetry in a busy Intensive Care Unit (ICU). Indirect calorimetry measurement results, along with clinical judgement will be used to adjust feeding prescription for the participant if required, as part of clinical practice. Study design: Prospective single-centre quantitative observational study conducted at Sir Charles Gairdner Hospital (SCGH) ICU, Perth, Australia commencing August 2021. Participant recruitment: The SCGH ICU Dietitian will screen ICU admissions daily on weekdays for eligibility criteria via a screening log. Population: Inclusion criteria includes admission to the ICU with a suspected infection requiring vasopressors, greater than or equal to 18 years of age and mechanically ventilated, with an expected ICU length of stay (LOS) of greater than 24 hours. Data collection: Recruited subjects will have an indirect calorimetry measure conducted by a Senior ICU Dietitian trained in indirect calorimetry each week day until extubation or after four weeks, whichever is reached first. The testing time for each indirect calorimetry measure will be a maximum of 60 minutes, and tests included with a minimum of five continuous minutes of steady state. Demographic, nutrition, clinical, indirect calorimetry, feasibility and outcome variables of interest will be collected daily for the duration of the study period (that is, until extubation or after four weeks, whichever is reached first). Indirect calorimetry results obtained will be considered based on clinical judgement for energy provision as part of the feeding regime.