A controlled trial of fixed versus tailored calorie intake in patients receiving intravenous feeding after abdominal surgery

Excessive intravenous calorie intakes have been shown to increase fat deposition and CO2 production with deleterious results. A controlled trial has therefore been performed to determine whether there is clinical benefit from tailoring calorie intake of intravenously fed patients to the patient's metabolic expenditure. Twenty patients requiring intravenous feeding after abdominal surgery were randomly allocated to receive either (i) a constant regimen containing 2 600 calories and 15.55 g nitrogen or (ii) a varied regimen with a fixed calorie: N2 ratio of 167:1 but with the calorie intake adjusted according to the previous day's metabolic expenditure. Only one patient had a requirement of greater than 2 600 calories; there was no difference in mean RQ during intravenous feeding between the constant regimen (0.90 +/- 0.10 s.d.) and the varied regimen (0.90 +/- 0.09 s.d.) and no significant difference in peak CO2 production. Excess calorie intake over expenditure did not correlate with increased positive nitrogen balance but on the varied regimen patients receiving a higher nitrogen intake tended to be in more positive nitrogen balance. This study suggests that a fixed calorie intake of 2 600 calories per day is suitable for adult patients requiring intravenous feeding after abdominal surgery but currently prescribed nitrogen intakes may be suboptimal.     

Prolonged impairment of cell-mediated immunity after major abdominal surgery in malnourished patients

The effect of the nutritional status on postoperative impairment of the immune response was studied in adults undergoing major abdominal surgery. The immune function was evaluated by measuring in vitro the lymphocytic response to phytohaemagglutinin (PHA), concanavalin A (Con A) and the purified protein derivative of tuberculin (PPD) in whole blood cultures, and in vivo delayed skin hypersensitivity to candida, mumps, streptokinase-streptodornase and PPD. Nutritional assessment was carried out by evaluating recent weight loss, the weight for height index and by measuring the arm muscle circumference (AMC), triceps skinfold thickness (TSF), the creatinine-height index (CHI) and the serum concentration of albumin and prealbumin. The patient was considered malnourished, if at least three of these criteria were abnormal. The immune parameters were measured preoperatively, at the end of the surgery and five days after operation. Before the operation both malnourished and well-nourished patients had normal lymphocytic responses, but the malnourished patients had a slower recovery of immune responses after the operation and they had an increased number of postoperative complications. No significant differences in the incidence of anergy were observed between the well and malnourished patients pre or postoperatively.     

Abnormal plasma amino acid profiles in patients undergoing bone marrow transplant

Amino acid concentrations in plasma have been measured during total parenteral nutrition in patients undergoing bone marrow transplantation. Profound hyperaminoacidemia was noted in the immediate para-transplant period. The increase was due mainly to high levels of phenylalanine and methionine. During the radiation treatment period these amino acids plus valine, proline, serine and glycine were exceptionally high. Levels of cystine and asparagine tended to be low. The results suggest that infusion of a mixture of amino acids which is lower in phenylalanine and methionine might result in better nitrogen utilization.     

A comparison of immediate post-operative enteral and parenteral nutrition in patients with gastric carcinoma

Fourteen patients with gastric carcinoma were studied in the first post-operative week following the administration of immediate post-operative nutrition. Eight received Clinifeed ISO^® enteral feed and six received parenteral nutrition (TPN) (Vamin-glucose, dextrose and Intralipid^®). Plasma albumin and transferrin concentrations decreased post-operatively in both groups, but did not differ significantly between the groups. Positive nitrogen balance was achieved on the fifth post-operative day in the enteral group and on the first post-operative day in the TPN group. There were no significant differences in the pre and post-operative weights and anthropometric measurements in either group. One patient in each group developed a subphrenic abscess, six patients in the enteral group experienced nausea and diarrhoea and two of these also vomited. The results indicate that immediate post-operative enteral nutrition is accompanied by a degree of negative nitrogen balance because a 3 day ‘build up’ period is necessary to achieve a full intake and with a higher incidence of minor gastro-intestinal complications which are easily controlled.     

A comparison of serum albumin, age and the Sheffield prognostic index in the prediction of surgical complications

The ability of the Sheffield prognostic index (S.P.I) to predict postoperative complications and death in patients undergoing gastrointestinal surgery has been compared with that of serum albumin alone, and with age. Both the S.P.I. and age were better at predicting complications than serum albumin. Serum albumin was the best predictor of death.     

Pattern of energy storage in the liver and muscle of rats submitted to total parenteral nutrition

TPN was administered to young male rats for 10 days at a low (270 kcal/kg/day) and a high (250 kcal/kg/day) energy level, with an isonitrogenous supply (0.9 g N/kg/day). The non-protein calories were divided into three energy substrate ratios: 0% Fat 100% Glucose , 6% Fat 94% Glucose , and 60% Fat 40% Glucose . Glycogen, acylglycerols and enzyme activities of the heart and some skeletal muscles (tib. anterior, ext. dig. longus and soleus) were unaffected by the various intravenous regimens. The glycogen content of the liver was significantly higher in both low fat groups. There was also a clear tendency in all groups to lower values of glycogen as the energy level of the TPN increased. The opposite trend was seen with acylglycerols, which were highest in the high glucose and high fat groups. The highest acylglycerol content was found in the high fat group at the high energy level. This study demonstrates that unbalanced intravenous regimens, without fat or with a fat overload (20 g/kg/day), seem to alter the storage pattern of glycogen and fat in the liver, particularly when hypercaloric regimens are given. The heart and skeletal muscles seemed to be protected from this effect.     

Nutritional intake after colorectal surgery: a comparison of a traditional and a new post-operative regimen

The energy and protein intake was studied for 12 days after colorectal surgery in 36 patients. Eighteen patients followed a traditional management with nasogastric suction until bowel movements occurred after which a liquid diet, protective diet and normal food were successively administered. In a subsequent period a new regimen was introduced. Nasogastric suction was not used. Instead, 18 patients received liquid diet from the first post-operative day and normal food, when the patient wanted to eat it. In addition, the nutritional intake was supplemented by protein-enriched refreshing drinks and milk products between the meals. The new regimen was tolerated without discomfort and resulted in a significant increase in protein intake (43 g/day vs. 26 g/day, p<0.001) and energy intake (78% vs. 71% of the basal metabolic rate, p<0.05). The increase was most pronounced in the first 4 days after the operation. Finally, the weight loss was significantly lower on the new regimen (1.8 kg vs. 3.9 kg, p<0.001).     

The effect of stress hormones on the interorgan flux of amino acids and on the concentration of free amino acids in skeletal muscle

Plasma concentrations of free amino acids have previously been found to decrease posttraumatically and this decrease can be reproduced by infusion of stress hormones. The mechanisms underlying this effect has not been investigated and therefore 14 healthy subjects were studied by infusing adrenaline alone or a combination of adrenaline, glucagon, and cortisol, in dosages giving pathophysiological plasma concentrations of the hormones. The influence on the interorgan fluxes of free amino acids and on the concentrations of free amino acids in skeletal muscle were determined. During hormone infusion splanchnic oxygen consumption doubled, indicating an increase in metabolic activity. There was a significant decrease in the arterial plasma level of all amino acids except alanine. Significant increases in alanine flux was noted, the release from one leg doubled and the splanchnic uptake increased by 60%. After only 1 h all essential amino acids showed a significantly decreased concentration in muscle while the level of alanine was increased. There were no differences between the two hormone groups. The results indicate that stress hormones can initiate an increased formation of alanine in skeletal muscle and an increase in alanine transport from the periphery to the splanchnic area.     

Energy replacement during parenteral nutrition in surgery, sepsis and cancer

For many years, the increased nutritional requirements of surgical, septic and cancer patients were identified, but no effective therapy existed for averting their negative calorie and nitrogen balance. Parenteral nutrition offered an answer in many of these situations. However, abnormalities in liver function, ventilatory load, hyperglycemia and a disturbed metabolic homeostasis showed that in excessive amounts, glucose can behave as a relatively toxic substance. For cases with increased energy expenditure, new alternatives had to be devised in order to avoid excessive glucose intakes. One obvious possibility in these cases was to refrain from offering more than the basal caloric needs, until the patient had passed the period of acute injury, or other measures had effectively controlled the sepsis or cancer. Other options included the partial substitution of glucose by lipids or amino acids. Preliminary information suggests that this approach could lead to better nutritional outcome and survival rates, but additional studies are required.     

Effect of a caloric supplement in malnourished patients with Crohn's disease

The purpose of this work was to evaluate the efficacy of adding a caloric supplement to the daily diet of malnourished outpatients with Crohn's disease in remission. Seven underweight patients following a one month period of weight-maintenance diet took 10 KCal/kg Ideal body weight/day of a nutritionally complete preparation (carbohydrates 82%, proteins 10%) as supplement for 2 months. At the end of this period, a significant increase in body weight (mean 3 ± 0.3%) as well as a sum of 10 skinfolds (mean 13.1 ± 4.0%) were observed. No significant change in arm muscle circumference was recorded. All the patients then continued with their weight-maintenance diet alone for a further 2 months and during this period a mean decrease of 0.65 ± 0.7% of body weight occurred. A caloric supplement may be a means of increasing body weight and anthromometric variables in underweight patients with Crohn's disease.     

Prospective study of nasogastric feeding via East Grinstead or Viomedex tubes compared with oral dietary supplementation in patients with cirrhosis

Forty-seven patients with alcoholic hepatitis and/or cirrhosis were randomised to receive nutritional supplementation by oral sip feeding or by nasogastric infusion administered via either an East Grinstead or a Viomedex nasoenteric tube. The three groups were well matched for severity and complications of liver disease. Patients fed by the nasogastric route attained their daily target dietary intake significantly more often than did those supplemented orally, but the consequent improvement in their nitrogen balance was not significant. There were no significant differences between nasogastric and sip feeding, or between the types of tube studied, in the frequency with which vomiting, diarrhoea or variceal bleeding occurred, but Viomedex tubes required reinsertion significantly less frequently than did the East Grinstead type.     

Origins of hyperphenylalaninemia in burn patients

Plasma phenylalanine concentrations were measured on the seventh postburn day in patients with burn surface areas ranging from 1 to 39%. Hepatic function (glutamate-pyruvate transaminase, prothrombin time) and protein breakdown (nitrogen balance, urine 3-methylhistidine/creatinine ratio) were evaluated in parallel. Plasma phenylalanine concentrations in patients with normal hepatic function and those with hepatic failure were similar. A correlation was shown between phenylalaninemia and nitrogen balance for all patients but phenylalaninemia only correlated with the urine 3-methyl-histidine/creatinine ratio in patients with burn surface areas under 20%. Taken as a whole, the data suggest that the determination of plasma phenylalanine concentration is a valuable test to assess the nitrogen balance in burn patients. This test, when performed on day 7, is particularly relevant in patients with normal hepatic function and either slight or moderate burn injury.     

Glucose balance and muscle glycogen during TPN in the early post-operative phase

In order to study how muscle glycogen is influenced by different nutritional regimens in the early post-operative period we took muscle biopsies from 20 patients preoperatively and on the fourth post-operative day after abdominal aortic surgery. Ten patients received 93% of non-protein energy as glucose, 7% as fat (Intralipid) and insulin was given to keep the blood glucose below 10 mmol/l. The remaining patients had 80% of non-protein energy as fat (Intralipid). Amino acids constituting 12 g of nitrogen daily were given to both groups. Daily measurements of gas exchange (oxygen uptake, CO2-production) were performed and from these data glucose balance was calculated as the difference between glucose intake and glucose expenditure. Muscle biopsies were analysed for glycogen, adenosine triphosphate, glucose-6-phosphate, lactate and citrate. We found that it was possible to maintain muscle glycogen stores at pre-operative levels with a glucose-insulin regimen. With the fat regimen there was a 31% decrease in muscle glycogen and two patients had a negative glucose balance despite the fact that 150 g of glucose were given. Average glucose balance throughout the study correlated positively with glucose intake. A significant correlation between glucose on the third day and change in muscle glycogen content was found. Muscle content of adenosine triphosphate, glucose-6-phosphate, lactate and citrate were similar in both groups.     

Nasogastric tube substitution for nutritional support in patients with oesophageal cancer: A simple method

A simple method is described allowing an easy and rapid substitution of nasogastric tubes for enteral nutrition in patients with stenosing oesophageal cancer, using the Seldinger technique.     

Comparison of forearm muscle dynamometry with nutritional prognostic index, as a preoperative indicator in cancer patients

We studied 95 patients with cancer of the gastrointestinal tract in various sites. The aim of the study was to compare the forearm dynamometry vs the prognostic nutritional index which was reported by Busby et al, 1890. We used these methods as preoperative prognostic indicators for postoperative mortality and morbidity. The forearm muscle dynamometry has greater positive predictive value (58.33 vs 32.4%), higher sensitivity (77.78 vs 66.6%), and specificity (86.11 vs 65.28%) than the prognostic nutritional index. The forearm muscle dynamometry predicted the patients mortality with a high rate of sensitivity (100%). The results suggest that dynamometry is a useful, rapid, and inexpensive test. It is more accurate than the nutritional index, and can identify cancer patients at a high risk of developing major postoperative complications, and predict the postoperative morbidity and mortality.     

Metabolic effects of four intravenous nutritional regimens in patients undergoing elective surgery II.--Muscle amino acids and energy-rich phosphates

Muscle amino acids and energy-rich phosphates have been determined in 28 patients before and after resection of a carcinoma of colon or rectum. Before operation the patients received a synthetic diet (Vivasorb for four days and postoperatively four different intravenous regimens with different amounts and proportions of amino acids were given for six days, the energy intake being the same for all groups. When compared with age-matched healthy controls the patients showed only slight increases in phenylalanine and isoleucine concentration in muscle and plasma with elevated plasma glutamate during the four days prior to the operation. Vivasorb treatment increased the concentration of alanine, glycine and methionine in both muscle and plasma while increases of threonine and histidine were seen only in muscle. Decreased concentrations of valine were found in muscle and plasma, while lysine and leucine decreased only in plasma. As an effect of operation, but independent of the nutritional regimen, muscle asparagine increased and muscle glutamine and glutamate decreased in all groups. The unique pattern of amino acid changes in postoperative trauma was confirmed in the present investigation but few differences in amino acid concentrations could be related to the various nutritional intakes. Alterations in the individual amino acid concentrations were not influenced by the intake of amino acids and seemed to have little relationship to the composition of any solution infused. Prior to operation there were low levels of ATP in muscle possibly due to immobilisation and chronic semistarvation but no changes in the energy rich phosphates could be attributed to trauma or nutrition. The content of muscle glycogen increased as a result of the Vivasorb supply indicating that the preoperative carbohydrate administration promotes muscle glycogen synthesis and postoperatively muscle glycogen was reduced significantly indicating enhanced glycogenolysis in the postoperative state. This finding emphasizes the importance of providing the patients with ample amount of glucose before and after surgery.     

Measurement of fatty acid oxidation in premature newborn infants with the 13C-triolein breath test

The 13C-triolein breath test is a method giving evidence of extent and rate of fatty acid oxidation in newborn infants on parenteral nutrition. The test has the special advantage of being non-invasive. Triolein labeled with the stable carbon isotope 13C and emulsified in soybean-oil is used as a tracer. 10 mg of 13C triolein per kg body weight are administered intravenously. The 13CO2 resulting from the fatty acid oxidation is analysed in expired breath by ratio-mass-spectrometry. The calculated 13C elimination is representative of the rate of fatty acid oxidation during the examination period. First studies on 15 premature infants have shown that an average of 27.0 +/- 1.8% of the dose administered is oxidized within 4 h. The present results suggest that the oxidation rate may be related to the maturity of the prematurely born infants.     

Changes in muscle and plasma amino acid metabolism in severe malnutrition--the influence of total parenteral nutrition

The concentrations of free amino acids in muscle and plasma were determined in nine female patients with severe anorexia nervosa before and after 3 to 5 weeks of total parenteral nutrition (TPN). The patients had lost 25 to 42% of their pre-morbid weight. During TPN their weight gain was around 2.5 kg/week. Initially total non-essential amino acids (NEAA) in muscle were decreased 30% compared to controls. The major part of this depletion was due to a 40% reduction in glutamine. After TPN the level of glutamine normalized. Alanine, being normal before TPN, decreased after TPN. Proline and several other non-essential amino acids in muscle were decreased before and after TPN. Total essential amino acids (EAA) in muscle were initially normal and were not significantly affected by TPN. Total NEAA in plasma were decreased at admission and normalized after TPN. Total EAA in plasma, however, were normal both before and after TPN. This study demonstrates that severely malnourished patients with anorexia nervosa have changes in amino acid patterns in both muscle and plasma. These changes were largely, though not completely, reversed after 3 to 5 weeks of TPN.     

Clinical implications of continuous measurement of energy expenditure in mechanically ventilated patients

Energy expenditure was monitored in 20 critically-ill mechanically ventilated patients using the Siemens-Elema Oxygen Consumption Calculator (OCC 980). Energy expenditure was measured continuously over the 24-h period in all patients (altogether, over 2500 patient hours; range 48-288 h). A predicted energy expenditure was calculated for each patient from standard tables for basal metabolic rates modified according to previously published reports on the influence of trauma, infection and elevated body temperature. For all patients combined, the agreement between the predicted and the measured energy expenditure was good. However, in individual patients the measured energy expenditure varied between 48 and 148% of the predicted value. The measured energy expenditure in surviving traumatized and/or septic patients correlated well (95-100%) with the predicted value at the time when weaning off the ventilator could be initiated. On the first day of measurements, the energy expenditure (in % of the predicted value) in the six patients who later died was significantly lower than in surviving patients (84 +/- 6 vs 107 +/- 2%; p < 0.01). Over a 24-h period, energy expenditure, defined as the value noted during a stable 30-40-min period of measurement, varied between 12 and 50% in the individual patients. This study shows that energy expenditure cannot be accurately predicted in the individual patient, that an energy expenditure below predicted values appears to be indicative of a poor prognosis and that short periods of energy expenditure monitoring may fail to reflect 24-h conditions.     

The metabolic status of internal intensive care patients as indicated by 3-methylhistidine excretion and nitrogen balance

The metabolic status of 15 intensive care patients receiving a standardized total parenteral nutrition regimen was followed up to 15 days immediately after admission by measuring 3-methylhistidine, total nitrogen, and creatinine excretion. The average 3-methylhistidine excretion was within the normal range during the first 3 days, rising on day 4 and reached a maximum of 70% above normal values on day 5. It declined to within normal range thereafter in most of the patients. Mean values for creatinine excretion remained relatively constant within the normal range throughout the study. During all days 3-methylhistidine was negatively correlated with N-balance. It is concluded that these patients had increasing catabolism with a maximum on day 5 and that the catabolic condition was associated with an increased muscle protein breakdown.