TOTAL-ENERGY EXPENDITURE DURING TOTAL PARENTERAL-NUTRITION - AMBULATORY PATIENTS AT HOME VERSUS PATIENTS WITH SEPSIS IN SURGICAL INTENSIVE-CARE

Background. To avoid the complications associated with overfeeding or underfeeding, the energy requirements of patients receiving total pare nteral nutrition (TPN) must be accurately prescribed. However, until r ecently it has not been possible to directly measure the rates of tota l energy expenditure (TEE) in. surgical patients receiving TPN. Method s. Values for total body water and TEE in four patients with sepsis (m ean Acute Physiology and Chronic Health Evaluation [APACHE] score, 10) receiving TPN in surgical intensive care unit and in four patients wi th chronic intestinal failure receiving long-term TPN at home (HPN) ha ve been determined by using the doubly labeled water technique. The va lues for TEE have been compared with those of resting energy expenditu re obtained with indirect calorimetry (REE CAL) and calculated by usin g the Harris-Benedict equation (REE HB). Results. In both the patients with sepsis and the patients receiving HPN the proportion of body wei ght made up of water was normal for patient age and gender. In patient s with sepsis the REE HB significantly (p < 0.05) underestimated the R EE CAL (15.39 +/- 3.80 kcal/kg/day(-1) versus 31.3 +/- 1.23 kcal/kg/da y(-1)) and was significantly less than the TEE derived by using doubly labeled water (44.62 +/- 1.09 kcal/kg/day(-1); p < 0.001). In the amb ulatory patients receiving HPN no difference was noted between the REE HB and the REE CAL (18.02 +/- 0.41 kcal/kg/day(-1) versus 21.37 +/- 0 .94 kcal/kg/day(-1)). The average TEE these patients was 30.25 +/- 3.4 2 kcal/kg/day(-1), and this was significantly greater (p < 0.006) than both REE CAL and REE HB. Conclusions. This investigation has shown th at in patients with sepsis TEE constitutes 1.4 times the REE CAL or ap proximately 40 kcal/kg/day, whereas in HPN patients TEE can be estimat ed by supplying 1.4 times the REE or approximately 30 kcal/kg/day(-1).