Hypocaloric Parenteral Nutrition Research Articles

Whole-body protein kinetics in critically ill patients during 50 or 100% energy provision by enteral nutrition: A randomized cross-over study.

Enteral nutrition (EN) is a ubiquitous intervention in ICU patients but there is uncertainty regarding the optimal dose, timing and importance for patient-centered outcomes during critical illness. Our research group has previously found an improved protein balance during normocaloric versus hypocaloric parenteral nutrition in neurosurgical ICU patients. We now wanted to investigate if this could be demonstrated in a general ICU population with established enteral feeding, including patients on renal replacement therapy. Patients with EN >80% of energy target as determined by indirect calorimetry were randomized to or 50% or 100% of current EN rate. After 24 hours, whole-body protein kinetics were determined by enteral and parenteral stable isotope tracer infusions. Treatment allocation was then switched, and tracer investigations repeated 24 hours later in a crossover design with patients serving as their own controls. Six patients completed the full protocol. During feeding with 100% EN all patients received >1.2 g/kg/day of protein. Mean whole-body protein balance increased from -6.07 to 2.93 µmol phenylalanine/kg/h during 100% EN as compared to 50% (p = 0.044). The oxidation rate of phenylalanine was unaltered (p = 0.78). It is possible to assess whole-body protein turnover using a stable isotope technique in critically ill patients during enteral feeding and renal replacement therapy. Our results also suggest a better whole-body protein balance during full dose as compared to half dose EN. As the sample size was smaller than anticipated, this finding should be confirmed in larger studies.

Postoperative Hypocaloric Peripheral Parenteral Nutrition With Branched-Chain-Enriched Amino Acids Provides No Better Clinical Advantage Than Fluid Management in Nonmalnourished Colorectal Cancer Patients

To assess clinical efficacy of using postoperative branched-chain amino acids (BCAAs)-enriched nutritional support in lower gastrointestinal cancer patients, we conducted a retrospective observational study comparing this regimen with traditional fluid management. Sixty-one eligible colorectal cancer patients consecutively admitted in the Colorectal Surgery Ward to receive postoperative hypocaloric peripheral parenteral nutrition (HPPN) were categorized into dextrose-only control group (n = 20), dextrose plus low-dose BCAA fat group (n = 20), and dextrose plus high-dose BCAA fat group (n = 21). Nutritional, clinical, and biochemical outcomes were collected on the day before and 7 days after surgery. Patients were nonmalnourished. Over the 7-day observation period, the control group had a significantly higher reduction in body mass index than the lower dose and the higher dose BCAA groups (P = 0.023 and P = 0.002, respectively). Compared to high-dose BCAA group, the control group also had a lower nitrogen excretion (P < 0.0001) and less reduction in nitrogen balance (P < 0.0001). There were no differences between study groups in biochemical measures, phlebitis, postoperative hospital stay, and in-hospital mortality. We found no better clinical advantage to the postoperative administration of BCAA-enriched HPPN than fluid management in nonmalnourished colorectal cancer patients.

Effect of hypocaloric versus normocaloric parenteral nutrition on whole body protein kinetics in critically ill neurosurgical patients

The optimal feeding of critically ill patients treated in the ICU is controversial. Present guidelines for protein feeding are based on weak evidence obtained with suboptimal methods. Whole body protein kinetics is an attractive technique to assess optimal protein intake by measuring the effect of protein feeding strategies on protein synthesis rates, protein degradation rates and protein balance. Here protein kinetics were measured in critically ill neurosurgical patients during hypocaloric and normocaloric parenteral nutrition.

Efficacy of hypocaloric parenteral nutrition for surgical patients: A systematic review and meta-analysis

Hypocaloric parenteral nutrition is an underfeeding strategy that lowers energy intake to around 20 kcal/kg/d. It is believed to achieve benefits by modulating metabolic responses and alleviating hyperglycemia. This study aims to systematically review the clinical efficacy of hypocaloric parenteral nutrition on surgical patients. Medline, SCI, Embase, Cochrane Library, Chinese Biomedicine Database (CBM) and China Knowledge Resource Integrated Database (CNKI) were searched for studies published before July 1, 2010. Randomized control trials (RCTs) that compared hypocaloric PN with standard or higher energy PN in surgical patients were identified and included. Methodological quality assessment was based on Cochrane Reviewers' Handbook and modified Jadad's Score Scale. Statistical software RevMan 5.0 was used for meta-analysis. Five trials met all inclusion criteria and were included in the final meta-analysis. There were significant reductions in infectious complications (RR, 0.60; 95%CI 0.39-0.91, P = 0.02; I(2) = 38%) and length of hospitalization (LOS) associated with receiving hypocaloric PN (MD-2.49 days, 95%CI -3.88 to -1.11, P = 0.0004; I² = 48%). Stratified analysis of the smaller trials (<60) and larger trials demonstrated that the heterogeneity between trials was mainly associated with sample size. When smaller trials were excluded, hypocaloric PN was associated with reduction in infectious complications (RR, 0.21, 95%CI 0.06-0.72, P = 0.01, I2 = 0%) and shortening of LOS (MD, -2.32 days, 95%CI -3.72 to -0.93, P = 0.001, I² = 0%). Hypocaloric parenteral nutrition may reduce infectious complications and the length of hospitalization in post-operative patients. However, this conclusion is tentative due to patient type and sample size. Furthermore, in terms of hypocaloric PN, the actual energy amount still varies a great deal (from 15 kcal/kg/d to 20 kcal/kg/d). This suggests that further research, including larger randomized clinical trials is required.

Treatment with growth hormone, somatostatin and insulin in combination with hypocaloric parenteral nutrition in gastrointestinal cancer patients after surgery

Objective The metabolic response to gastrointestinal cancer in patients undergoing surgery is associated with hypermetabolism and insulin resistance. The potential use of synergetic anabolic hormones in conjunction with hypocaloric parenteral nutrition ( HPN) has become a significant area of investigation. The current study was performed to determine the clinical efficiency and safety of combined hormone therapy in addition to HPN in gastrointestinal cancer patients. Methods One hundred patients with the nutrition risk screening ( NRS) score of 3 or 4 undergoing surgery for gastrointestinal cancer were randomized into two groups. The patients in the control group received standard total parenteral nutrition (TPN) and systemic insulin. The patients in the study group received HPN and systemic insulin in addition to the pretreatment of recombinant human growth hormone ( r-hGH) and octreotide. Clinical efficiency and safety were evaluated by the measurement of hormones and protein metabolites, immune function, clinical outcome,and adverse events. Follow-ups were performed to determine the influence on prognosis. Results Treatment with r-hGH, octreotide, and insulin in combination with HPN significantly increased protein synthesis , immune function and metabolic tolerance, decreased infectious complications, and shortened postoperative hospital stays, but did not increase the risk of tumor development and recurrence in the study group compared to the control group. Conclusion The proper short-term perioperative administration of growth hormone,somatostatin,and insulin in combination with HPN can overcome the postoperative stress response through the increase of protein synthesis to improve immune function in gastrointestinal cancer patients after surgery. Key words: Hypocaloric parenteral nutrition; Recombined human growth hormone; Somatostatin ,cancer

Treatment with growth hormone, somatostatin, and insulin in combination with hypocaloric parenteral nutrition in gastrointestinal cancer patients after surgery

Objective The metabolic response to gastrointestinal cancer in patients undergoing surgery is associated with hypermetabolism and insulin resistance. The potential use of synergetic anabolic hormones in conjunction with hypocaloric parenteral nutrition (HPN) has become a significant area of investigation. The presented study was performed to determine the clinical efficiency and safety of hormone therapy combined with HPN in patients with gastrointestinal cancer. Methods One hundred patients with a Nutrition Risk Screening score of 3 or 4 undergoing surgery for gastrointestinal cancer were randomized into two groups. The patients in the control group received standard total parenteral nutrition and systemic insulin. The patients in the study group received HPN and systemic insulin in addition to pretreatment with recombinant human growth hormone and octreotide. Clinical efficiency and safety were evaluated by the measurement of hormones and protein metabolites, immune function, clinical outcome, and adverse events. Follow-ups were performed to determine the influence on prognosis. Results Treatment with recombinant human growth hormone, octreotide, and insulin in combination with HPN significantly increased protein synthesis, immune function, and metabolic tolerance, decreased infectious complications, and shortened postoperative hospital stays, but did not increase the risk of tumor development and recurrence in the study group compared with the control group. Conclusion The proper short-term perioperative administration of growth hormone, somatostatin, and insulin in combination with HPN can overcome the postoperative stress response through the increase of protein synthesis to improve immune function in patients with gastrointestinal cancer after surgery.

Nutrition therapy in the critical care setting: What is “best achievable” practice? An international multicenter observational study*

To describe current nutrition practices in intensive care units and determine "best achievable" practice relative to evidence-based Critical Care Nutrition Clinical Practice Guidelines. An international, prospective, observational, cohort study conducted January to June 2007. One hundred fifty-eight adult intensive care units from 20 countries. Two-thousand nine-hundred forty-six consecutively enrolled mechanically ventilated adult patients (mean, 18.6 per site) who stayed in the intensive care unit for at least 72 hrs. Data on nutrition practices were collected from intensive care unit admission to intensive care unit discharge or a maximum of 12 days. Relative to recommendations of the Clinical Practice Guidelines, we report average, best, and worst site performance on key nutrition practices. Adherence to Clinical Practice Guideline recommendations was high for some recommendations: use of enteral nutrition in preference to parenteral nutrition, glycemic control, lack of utilization of arginine-enriched enteral formulas, delivery of hypocaloric parenteral nutrition, and the presence of a feeding protocol. However, significant practice gaps were identified for other recommendations. Average time to start of enteral nutrition was 46.5 hrs (site average range, 8.2-149.1 hrs). The average use of motility agents and small bowel feeding in patients who had high gastric residual volumes was 58.7% (site average range, 0%-100%) and 14.7% (site average range, 0%-100%), respectively. There was poor adherence to recommendations for the use of enteral formulas enriched with fish oils, glutamine supplementation, timing of supplemental parenteral nutrition, and avoidance of soybean oil-based parenteral lipids. Average nutritional adequacy was 59% (site average range, 20.5%-94.4%) for energy and 60.3% (site average range, 18.6%-152.5%) for protein. Despite high adherence to some recommendations, large gaps exist between many recommendations and actual practice in intensive care units, and consequently nutrition therapy is suboptimal. We have identified "best achievable" practice that can serve as targets for future quality improvement initiatives.

Randomized Controlled Study of Glycerol Versus Dextrose in Postoperative Hypocaloric Peripheral Parenteral Nutrition

The aim of this study was to use glycerol and dextrose in hypocaloric peripheral parenteral nutrition (HPNN) and investigate their effects on postoperative metabolic and nutritional responses. Thirty patients who had undergone major gastrointestinal surgery were examined in a prospective randomized study. The study period extended from the day before operation to postoperative day 7. Fifteen patients (intervention group) received 1.2 g amino acids, 1.2 g glycerol, and 0.5 g fat emulsion/kg/day (approximately 15 kcal/kg/day). The other 15 patients (control group) received 1.2 g amino acids, 1.5 g dextrose, and 0.5 g fat emulsion/kg/day (approximately 15 kcal/kg/day). After 7 days of study, both groups were found to have a decrease in body weight, mid-arm circumference, triceps skin fold, serum albumin, and transferrin and prealbumin levels, but an increase in serum cholesterol and triglyceride levels. However, the differences between them were not significant. Improvements in nitrogen balance were observed in the intervention group (p =. 035). These data suggest that advantages favoring the administration of glycerol instead of dextrose in hypocaloric parenteral nutrition could hardly be found in our investigation, except that better nitrogen equilibrium is maintained. Nonetheless, the peripheral intravenously administered ProcalAmine with fat emulsion has been well tolerated and safe for these patients, as well as more convenient for clinical use.

Randomized Clinical Trial of the Anabolic Effect of Hypocaloric Parenteral Nutrition After Abdominal Surgery

Randomized Clinical Trial of the Anabolic Effect of Hypocaloric Parenteral Nutrition After Abdominal Surgery

Randomized clinical trial of the anabolic effect of hypocaloric parenteral nutrition after abdominal surgery

The observed failure of hypocaloric nutrition to establish an anabolic state after surgery may reflect inadequate control for the type and quality of analgesia in the studies performed. This study was designed to test the hypothesis that hypocaloric nutrition induces anabolism in patients who receive effective segmental pain relief using perioperative epidural analgesia. Sixteen patients who underwent colorectal surgery and received epidural analgesia were randomly assigned to receive intravenous glucose either without (glucose only) or with amino acids (nutrition). Feeding was administered over 48 h from surgical skin incision until the second day after operation. Glucose provided 50 per cent of the patient's resting energy expenditure (REE). Amino acids were infused at rates that provided 20 per cent of REE. Leucine rate of appearance (Ra), leucine oxidation and non-oxidative leucine disposal (NOLD) were assessed by measuring L-[1-13C]leucine kinetics. A positive leucine balance, that is the difference between NOLD and leucine Ra, indicated anabolism. After surgery, leucine Ra in the nutrition group was lower than that in the glucose only group (mean(s.d.) 88(25) versus 131(22) micromol per kg per h). The leucine balance remained negative in the glucose only group, whereas it became positive in the nutrition group (mean(s.d.) -24(3) versus 38(12) micromol per kg per h; P < 0.001). Patients who receive hypocaloric parenteral nutrition can be rendered anabolic after colorectal surgery in the presence of epidural analgesia.

Impact of postoperative treatment with recombinant human growth hormone and hypocaloric parenteralnutrition on gastrointestinal cancer

Impact of postoperative treatment with recombinant human growth hormone and hypocaloric parenteralnutrition on gastrointestinal cancer

The optimal nitrogen proportion to non-protein calories in normal rats receiving hypocaloric parenteral nutrition

The purpose of this study was to determine the optimal ratio of amino acids, in terms of the ratio of non-protein calories to nitrogen (NPC/N ratio), in peripheral parenteral nutrition (PPN). Test solutions that NPC/N ratio is 50, 100, 150 or 200, or amino acid free solution were administered parenterally at a rate of 120 kcal/kg/day for 5 days to normal rats, after which the effects of amino acid on protein metabolism were assessed. Cumulative nitrogen balance increased with a decrease in the NPC/N ratio (with a increase in amino acid dose), but there were no statistically significant differences between group NPC/N: 50, group NPC/N: 100, and group NPC/N: 150. The protein synthesis rate in the liver increased with a decrease in the NPC/N ratio, and the value in group NPC/N: 200 and group NPC/N: 150 was significantly lower than that in group NPC/N: 50. However, in group NPC/N: 50, the levels of serum urea nitrogen (SUN) and serum branched chain amino acids (BCAA) were high, suggesting the excessive administration of amino acids. Based on the above findings, the optimal NPC/N ratio is estimated to be about 100 (50 g as amino acids), when the intravenous solution is administered at the anticipated daily dose in clinical use (1000 kcal/day).

Considerations in Feeding Obese Patients: A Review of a Classic Article

Thirteen obese patients requiring parenteral nutrition for postoperative complications were studied prospectively to evaluate the efficacy of hypocaloric, high‐protein parenteral feeding. Nonprotein caloric intake averaged 881 kcal/d or 51.5% of the patients' measured resting energy expenditure. Protein averaged 2.13 ± 0.59 g/kg ideal body weight (IBW). Serum albumin and TIBC increased significantly (2.8 ± 0.5 g/dL to 3.2± 0.4 g/dL, p &lt; .01 and 196 ±39 μg/dL to 248 + 49μ g/dL, p &lt; .05, respectively), and subjects lost weight (120.0± 60.0 kg to 109.7 ±32.5 kg, p &lt; .05). Nitrogen balance studies in 8 subjects suggested nitrogen equilibrium or positive balance can be achieved (+2.4 ± 1.9 g/dL). All patients exhibited complete tissue healing of wounds and abscess cavities and closure of fistulae. In obese, protein‐depleted surgical patients, net protein anabolism and clinical efficacy can be achieved with hypocaloric, high‐protein feeding. Abundant endogenous fat stores provide obligatory energy. (Dickerson RN, Rosato, E, Mullen JL. New protein anabolism with hypocaloric parenteral nutrition in obese stressed patients.

Current Literature: Hypocaloric Parenteral Nutrition Support in Elderly Obese Patients

Hypocaloric nutrition support has been successfully used to achieve positive nitrogen balance in obese patients. However, advanced age is associated with changes in substrate metabolism. To evaluate the efficacy of this practice in elderly patients, we retrospectively reviewed 30 obese patients requiring parenteral nutrition support. Total caloric requirements (TCR) were calculated on the basis of the Harris‐Benedict equation. Patients were given a minimum of 1.5 g/kg/day protein, 75% of TCR when current body weight was &gt;120 and ≤150% of ideal body weight (IBW), and 60% of TCR if current body weight was &gt;150% of IBW. The patients were divided into two groups: group I (N = 18) patients were age &lt;60 and group II (N = 12) patients were ≤60 years of age. Only one of the group I patients (143.2 ± 25.7% IBW, received 18.2 ± 3.7 keal/kg/day and 1.6 ± 0.4 g/kg/day protein), but five of the group II patients (141.3 ± 14.4% IBW, received 18.3 ± 2.6 keal/kg/day and 1.7 ± 0.3 g/kg/day protein), had negative nitrogen balance (p = .025). Apparently, elderly obese patients have limited capacity to mobilize their fat stores as energy sources and may continue to undergo protein catabolism with hypocaloric high‐protein nutrition support. Therefore this form of nutrition support should be used with caution in elderly obese patients. (Am Surg 66:394–400, 2000)

Hypocaloric Parenteral Nutrition Support in Elderly Obese Patients

Hypocaloric nutritional support has been successfully used to achieve positive nitrogen balance in obese patients. However, advanced age is associated with changes in substrate metabolism. To evaluate the efficacy of this practice in elderly patients, we retrospectively reviewed 30 obese patients requiring parenteral nutrition support. Total caloric requirements (TCR) were calculated on the basis of the Harris-Benedict equation. Patients were given a minimum of 1.5 g/kg/day protein, 75 per cent of TCR when current body weight was >120 and < or =150 per cent of ideal body weight (IBW), and 60 per cent of TCR if current body weight was >150 per cent of IBW. The patients were divided into two groups: Group I (N = 18) patients were age <60 and Group II (N = 12) patients were > or =60 years of age. Only one of the Group I patients (143.2 +/- 25.7% IBW, received 18.2 +/- 3.7 kcal/kg/day and 1.6 +/- 0.4 g/kg/day protein), but five of the Group II patients (141.3 +/- 14.4% IBW, received 18.3 +/- 2.6 kcal/kg/day and 1.7 +/- 0.3 g/kg/day protein), had negative nitrogen balance (P = 0.025). Apparently, elderly obese patients have limited capacity to mobilize their fat stores as energy sources and may continue to undergo protein catabolism with hypocaloric high-protein nutrition support. Therefore, this form of nutritional support should be used with caution in elderly obese patients.

Influence of surgical stress and parenteral nutrition on serum leptin concentration

Experimental studies suggest that leptin may be an important metabolic signal for energy regulation.Aim: To assess whether surgical stress produces changes in serum leptin concentration and to investigate and compare the effect of total parenteral nutrition and hypocaloric parenteral nutrition on serum leptin levels.Patients and methods: Twenty-two surgical patients (11 male and 11 female) in need of parenteral nutrition were recruited. Parenteral nutrition was always initiated 24 h after surgical procedure. Group I (n=15) received total parenteral nutrition, while Group II (n=7) were treated with hypocaloric parenteral nutrition. Serum leptin concentration was determined before surgical procedure (day −1), after surgery and before parenteral nutrition was started (day +1), and after 5 days of treatment with parenteral nutrition (day +6).Results: A tendency to increase serum leptin levels was observed after surgical procedure (6.0±1.9 vs 9.9±2.7 ng/ml;P= 0.07). After starting parenteral nutrition no significant changes on serum leptin concentrations were found in both groups, but a trend to raise serum leptin was observed in Group I (6.2±1.7 vs 8.3±2.7 ng/ml) whereas a trend to decrease serum leptin was detected in Group II (4.6±2.5 vs 1.6±0.5 ng/ml). On day +6 an increase of serum leptin and insulin levels was observed in Group I in comparison with Group II (8.3±2.7 vs 1.6±0.5 ng/ml;P⪡ 0.05 and 58±41 vs 12±15 μU/l;P⪡ 0.05 respectively). Finally, a positive correlation at day +6 between insulin and serum leptin levels was observed (r= 0.66;P⪡ 0.01).Conclusions: a) Surgical stress is associated to an increase of serum leptin concentrations; b) Total and hypocaloric parenteral nutrition produces quite different effects on serum leptin levels that could be related to distinct insulin response.

Comparison of Glucose and Fat as Energy Sources in Peripheral Parenteral Nutrition in Rats.

Glucose is usually chosen as the energy source for total parenteral nutrition. However, the optimal glucose:fat ratio for peripheral parenteral nutrition has not been examined sufficiently. We compared glucose:fat ratios in hypocaloric nutrition. Male SD rats were given hypocaloric parenteral nutrition (approx. 190 kcal/kg/d) for 5 d after laparotomy. The hypocaloric solutions used contained 0, 33, 50, 67 or 100% of the non-protein energy in the form of fat. Body weight change, nitrogen balance, organ weights, and hepatic, splenic and plasma biochemistries were assessed. Body weight increase in the 67 and 100% fat groups was significantly greater than that in the 0% fat group. Nitrogen balance was the same in all groups. Hepatic glycogen content was significantly lower in the 100% fat group than that in the 0% fat group. The weight of epididymal fat deposits was significantly lower in the 0% fat group than in the 50 and 67% fat groups. On the other hand, tissue triglyceride content and plasma lipid levels in the 100% fat group were significantly higher than in the 0% fat group, and were also higher than in the control group. It is suggested that combinations of glucose and fat have sparing effects on body fat and hepatic glycogen. Combinations of glucose and fat as non-protein energy sources were superior to glucose or fat alone for hypocaloric parenteral nutrition.

Posttraumatic Hypocaloric Parenteral Nutrition – Development and Clinical Application

The use of hypocaloric parenteral nutrition (HPN) is very common in surgical medicine because it allows for a standardized peripheral venous supply of nutrients. HPN causes very little stress to the posttraumatically labile carbohydrate metabolism-this applies to the use of glucose as well as to sugar substitutes: For example, mean glucose concentrations in serum on glucose administration of 2-3 g/kg/day are between 5.5 and 8.4 mmol/l. The mean dose of amino acids of 1.0-1.2 g/kg/day commonly used in HPN leads to a 50-67% improvement in the N-balance compared to an exclusive water/electrolyte supply or the administration of 2 g of carbohydrates per kg and day. Even a high caloric nutritional therapy leads to no significantly improved N-balances on the first posttraumatic days. HPN is recommended after major surgery and severe trauma in order to better estimate the individual metabolic reaction to nutritional supply prior to any consumption-orientated parenteral nutrition. HPN is also important as an adjunct to early-phase enteral nutrition. Its value after moderate surgical interventions is questionable because studies have yet to confirm HPN's clinical efficacy. HPN should not be used after minor surgery or brief periods of fasting. A possible, but as yet uncertified indication for HPN is the longer-term nutrition of very obese patients.

Effect of Balanced Amino Acid Solution on Protein Metabolism after Surgery

The aim of this study was to investigate the nitrogen-sparing effect of hypocaloric parenteral nutrition (HPN) with a balanced amino acid supply compared with that of a standard Rose's formula. Eighteen well-nourished patients with colorectal cancer were randomly distributed into 3 groups: I control, II Study group, III Rose's formula. The amount of non-protein calories was similar in both groups: 8 kcal/kg administered as glucose, and 1.33 g of amino acid/kg was also infused during 5 days. There were no differences in the plasma protein levels of total proteins, albumin, and transferrin, but retinol-binding protein was higher in group II compared with the control. Nitrogen balance was significantly better in group II than in group III during the 3rd and 4th days. There were differences in the concentration of aspartic acid and glycine in the plasmatic aminograms between groups II and III. It was concluded that the balanced amino acid solution does not significantly improve a patient's nutritional state. Nor have we observed that the balanced amino acid solution causes fewer modifications in the plasma aminograms. However, it does achieve a slight improvement in the nitrogen balances and the synthesis of retinol-binding protein.

Regulation of ketone body flux in septic patients.

To assess the effect of sepsis on ketone body (KB) kinetics in humans, we measured in normal and septic subjects KB appearance rate (Ra) before (initial state) and during a rise of free fatty acids (FFA) level (intravenous infusion of a triglycerides emulsion). We studied normal subjects in postabsorptive state and septic patients when receiving an hypocaloric intravenous infusion of glucose and amino acids or 12 h after its interruption. When receiving glucose and amino acids infusion, septic patients had higher glucose and insulin levels than normal subjects, and despite lower FFA concentrations (255 +/- 44 vs. 480 +/- 51 mumol/l, P less than 0.05) comparable initial KB Ra (2.50 +/- 0.10 vs. 2.48 +/- 0.30 mumol.kg-1.min-1). Triglyceride infusion increased FFA to comparable values (septic 780 +/- 130, normal 730 +/- 45 mumol/l), but KB Ra rose in septic patients only to 3.7 +/- 1.1 instead of 7.7 +/- 1.1 mumol.kg-1.min-1 as in normal subjects (P less than 0.05). Somatostatin infusion decreased the hyperinsulinemia of septic patients but did not restore a normal ketogenesis. After interruption of nutriment infusion, septic patients had normal FFA levels and only mild hyperglycemia and hyperinsulinemia. Their initial KB Ra was not modified. However, their response of KB Ra (increase to 6.27 +/- 2.0 mumol.kg-1.min-1) to raised FFA levels (842 +/- 170 mumol/l) was comparable to the response of normal subjects. In conclusion, although septic patients receiving an hypocaloric parenteral nutrition had a depressed ketogenesis they were able to restore a normal ketogenic capacity after a short-time caloric deprivation. Glucose and/or insulin appears to have a major role in this modulation of hepatic ketogenesis.