Severe Weight Loss and Hypermetabolic Paroxysmal Dysautonomia Following Hypoxic Ischemic Brain Injury: The Role of Indirect Calorimetry in the Intensive Care Unit

Abstract

A 14-year-old girl with hypoxic ischemic brain injury developed multiple paroxysms (storms) of dysautonomia. She had a dramatic weight loss of 20 kg over 8 weeks. Resting energy expenditure measured by indirect calorimetry during an autonomic storm was 309% of predicted resting energy expenditure, indicating extreme hypermetabolism. Energy intake and expenditure calculations showed cumulative energy deficits during the period of weight loss. The frequency of her hypermetabolic events increased daily energy needs that were unmatched by her intake, which was calculated from standard equations. Weight stabilized soon after nutrient intake was titrated to account for her heightened energy expenditure. This case illustrates an important nutrition complication of dysautonomic storms in children with brain injury. Regular weight checks during the intensive care course allow detection of weight loss from underfeeding. Measurement of energy needs is prudent when weight loss is unexplained or increased energy expenditure is suspected. In hospitalized patients with metabolic fluctuations, accurate measurement of energy requirements by indirect calorimetry allows serial monitoring of energy balance and may guide nutrition intake to prevent cumulative energy deficits.