A methodological and clinical approach to measured energy expenditure in the critically ill pediatric patient.

The metabolic response to injury and stress is characterized initially by a decreased energy expenditure (Ebb phase) followed by an increased metabolic expenditure (Flow phase). Indirect calorimetry is a methodology utilized to measure energy expenditure and substrate utilization by measuring gas exchange in exhaled air and urinary nitrogen. The use of indirect calorimetry in critically ill patients requires precise equipment to obtain accurate measurements.

Dead space ventilation in critically ill children with lung injury.

Study Objective: In children with acute lung injury, there is an increase in minute ventilation (E) and inefficient gas exchange due to a high level of physiologic dead space ventilation (VD/VT). Mechanical ventilation with positive end-expiratory pressure, when used in critically ill patients to correct hypoxemia, may contribute to increased VD/VT. The purpose of this study was to measure metabolic parameters and VD/VT in critically ill children.