This study was designed to identify whether significant energy deficits occur when feedings are (1) withheld perioperatively and (2) withheld because of gastric ileus. We studied patients with more than 20% total body surface area burns, who had survived at least one surgery, and who were intubated within 3 days of admission. Energy needs and energy received from enteral feedings were summed across the period during which the patients underwent surgical procedures. The difference between energy needed and energy received was divided into that caused by feedings being withheld perioperatively and that caused by feedings being withheld because of a gastric ileus. Twenty-five patients (9 women and 16 men) were included in the study. The total energy deficit was a mean of 15,969 kcal (31.6% of 50,546 kcal needed); 58% of the energy deficit (9264 kcal of the 15,969 kcal deficit) was caused by feedings being withheld perioperatively and 42% of the energy deficit (6705 kcal of the 15,969 kcal deficit) was caused by feedings being withheld because of gastric ileus. The withholding of feedings perioperatively and because of gastric ileus were both significant contributors to energy deficits. Future studies are necessary to determine whether energy needs being more closely met would result in improved outcomes for these patients.