Evaluation of oxygen consumption and resting energy expenditure in critically ill patients with systemic inflammatory response syndrome

Objective: To determine whether oxygen consumption ((V) over dot O-2), CO2 production, and resting energy expenditure (REE) in critically ill patients differ in varying grades of systemic inflammatory response syndrome (SIRS) . Design: Prospective, clinical study. Setting: Intensive care unit at a university hospital. Patients: Twenty-six critically ill patients requiring mechanical ventilati on, Interventions: None, Measurements and Main Results:A total of 100 metabolic measurements were pe rformed. The grade of SIPS and the Acute Physiology and Chronic Health Eval uation II score were evaluated at the time of the metabolic cart study. (V) over dot O-2 and REE differed among the groups inadequate for SIRS (non-Sl RS), with SIRS without infection (nonseptic SIRS), and with SIPS with infec tion (septic SIRS) (125 +/- 37 mL/min/m(2) and 855 +/- 204 kcal/day/m(2), 1 35 +/- 33 mL/min/m(2) and 948 +/- 214 kcal/day/m(2), and 166 +/- 55 mL/min/ m(2) and 1149 +/- 339 kcal/day/m(2), respectively; p < .005). Patients with septic SIRS had higher (V) over dot O-2, and REE than patients with non-SI RS and nonseptic SIRS, Conclusion: (V) over dot O-2 and REE differ among groups of patients with n on-SIPS, nonseptic SIPS, and septic SIPS, Patients with septic SIRS have hi gher (V) over dot O-2, and REE than patients with non-SIRS or nonseptic SIP S, The present study shows that classifying patients into three grades (non -SIRS, nonseptic SIRS, and septic SIRS) is a valid predictor of metabolic s tress in critically ill patients.