| Abstract: | The application of the standard battery of nutritional assessment tests, measurements, and calculations is of limited value in the immediate nutritional diagnosis of the critically ill patient. Many of these tests are affected by stress, making it impossible to distinguish the etiology of abnormalities during the early postinjury period. Altered test results because of stress or injury include: increased excretion of creatinine; increased white blood cell (WBC) counts; increased anergy to skin tests; and decreased serum albumin, transferrin, thyroxin-binding prealbumin, and retinol-binding protein concentrations. Therefore, in assessing the nutritional status of the critically ill patient, it is important to focus on indexes that are realistic relative to the patient's metabolic status. Timing of data collection is of keen importance; data collected after fluid resuscitation and the peak metabolic response to injury on postinjury days 5 through 10 are usually more meaningful than those collected immediately after hospital admission. Admission assessment is necessary only to identify the high-risk patient in need of immediate nutrition intervention, to estimate energy/nutrition and fluid requirements, and to provide guidelines for planning nutrition care. This article presents recommendations for initial assessment, postcatabolism assessment, and serial assessment of the critically ill patient. Guidelines for estimating energy/nutrient requirements and timing data collection are also presented. |
