[Home enteral nutrition. Annual report 1999. NADYA-SENPE Group]

GOAL

During 1999, as in previous years, the NADYA-SENPE Group has maintained an annual register of patients with Artificial Nutrition at Home in order to keep up to date our available knowledge of this therapy. The present paper analyzes the results of the sixth National Register of patients under treatment with Enteral Nutrition at Home corresponding to 1999, produced with the co-operation of twenty-three centres in the Spanish national health network.

MATERIAL AND METHODS

The data were collected through a closed questionnaire included on our web site (www.nadya-senpe.com). Apart from epidemiological information, the form includes the indication that led to the prescription of nutrition, nutritional treatment, access path, complications and admissions to hospital, follow-up of the treatment, patients' quality of life and progress. All of the data are processed by the co-ordinating team. The Nutrition Unit at La Paz Teaching Hospital in Madrid has acted as the group co-ordinator.

RESULTS

During 1999, a total of 2,262 patients at the twenty-three collaborating centres followed treatment with Home Enteral Nutrition (NED in its Spanish acronym). The mean age was 63.6 (19.67 years (males: 57.6%; females: 42.3%). The mean time with nutritional treatment is 5.89 (4.25 months. The neurological alterations (37.5%) and neoplasias (36.8%) were the most frequent indications for NED. Most patients used oral administration (50.7%), the use of artificial routes is less frequent, with 5NG being used on 27.9% and PEG on 12.7%. The polymeric formulas are the ones most commonly used (87.7%). The number of complications recorded amounted to 1,403 episodes, representing 0.62 complications per patient per year, of which 40.8% were gastro-intestinal (0.26 complications per patient per year) and 18.7% were mechanical complications, with only 9 recorded cases of bronchoaspiration. It was necessary to admit patients to hospital on 836 occasions (0.38 admissions per patient), albeit generally for causes not associated with nutrition (86.1%). At year-end, 51.4% of patients continued to receive nutritional support.

CONCLUSIONS

Enteral nutrition at home is a safe technique whose use is growing in Spain. It requires the existence of appropriately equipped nutrition teams as well as the collaboration of the Primary Health Care services and the suitable training of patients and relatives. It is essential to progress more deeply into the development and application of clinical routes that provide a clear and concise methodology covering all nutrition-related aspects. In itself, nutrition is a therapeutic alternative regardless of whether access is obtained through a natural or an artificial route. It is necessary for the persons responsible for health-care administration to realize that the appropriate nutrition of patients leads to an improvement in their general health, a shorter course for their illness and, therefore, a reduction in costs.

Serum leptin levels in male marathon athletes before and after the marathon run

Leptin is a hormone produced by the adipocytes to regulate food intake and energy expenditure at the hypothalamic level. It is commonly accepted that the main determinants of leptin secretion are the net amount of body fat and the mean size of adipocytes. On the contrary, important vectors of energy flux in the organism, such as food intake and energy expended on exercise, are not thought to be regulators of that secretion. To understand whether leptin is regulated by an acute energy expenditure such as strenuous exercise, 29 male athletes who had trained for marathon running were studied before and after a marathon run and compared with 22 nonobese, age-, sex-, and body mass index (BMI)-matched sedentary controls. Controls and marathon athletes showed no differences in BMI or fat-free mass. Marathon runners showed a strong reduction in total fat mass (6.2 +/- 0.4 kg; 9.1 +/- 0.5% of body fat) compared with controls (12.3 +/- 0.5 kg; 16.1 +/- 0.5% of body fat; P < 0.05). This difference in body composition was paralleled by a mean serum leptin level that in marathonians (2.9 +/- 0.2 micrograms/L) was significantly (P < 0.05) reduced compared with that in controls (5.1 +/- 0.6 micrograms/L). It is remarkable that the ratio of leptin per kg body fat, showed a very good agreement between the two groups, 0.40 +/- 0.04 microgram/L.kg for controls and 0.46 +/- 0.03 microgram/L.kg for marathonians. In the two groups, leptin was correlated with both body weight, BMI, and fat mass (P < 0.001). The marathon trajectory was the standard 42.195 km accomplished in an average time of 3 h, 17 min, 7 s, with a calculated energy expenditure of over 2800 Cal. After the marathon run, a water imbalance occurred, with a significant decrease in body weight and an increase in serum albumin. A significant (P < 0.05) reduction in leptin values was observed after the run (2.6 +/- 0.2 micrograms/L) compared with before (2.9 +/- 0.2 micrograms/L), which was more relevant considering the relative hemoconcentration. In conclusion, 1) compared with sedentary subjects, leptin levels are reduced in male marathon runners in parallel with the relevant reduction in total body fat; 2) expressed as a ratio of leptin per kg body fat, no differences were observed between marathonians and controls; and 3) after an energy expenditure of 2800 Cal in the marathon run, a reduction in leptin levels occurred. Strong changes in energy expenditure may regulate serum leptin levels in man.

[Percutaneous endoscopic gastrostomy and gastrojejunostomy. Experience and its role in domiciliary enteral nutrition]

Percutaneous Endoscopic Gastrostomy (PEG) and its variation Percutaneous Endoscopic Gastrojejunostomy (PEGJ), has become the method of choice to achieve an enteral access route in patients who require long term enteral nutrition, especially in the area of the At Home Enteral Nutrition (AHEN). We present our experience on the first PEG's and PEGJ's carried out in our hospital.

MATERIAL

We studied 48 patients (14 women and 34 men) in whom a PEG/Percutaneous Endoscopic Gastrojejunostomy (PEGJ) was indicated, as they required enteral nutrition for prolonged periods of time (> 4 weeks) and/or they presented obstructive dysphagia, neuromotor dysphagia, or incorrigible vomiting in the two cases in whom PEGJ was carried out. 34 patients underwent the Ponsky-Gauderer technique, 6 patients underwent the Sacks-Vine technique, and 2 patients underwent a PEGJ. 24 hours after the PEGJ enteral nutrition (EN) was begun in a progressive manner. During the hospitalization period there was a daily follow up of the patient. In those cases in which At Home Enteral Nutrition was programmed, the patients/families were trained in the techniques and the care of the PEG and the EN, and the control was carried out through the Nutrition out patient department.

RESULTS

PEG was successfully carried out in 42 patients (88%). 35 patients had previously been given EN through a naso-gastric tube (NGT), while in 7 cases the PEG was the first enteral access route. The average duration of the PEG was 212 days, and 27 patients (64%) needed the PEG for more than 3 months. The mean caloric supply was 1921 +/- 200 kcal/day. The mode of administration was by means of an intermittent infusion by gravity in 31 cases, and by continuous infusion using a volumetric pump in 11 patients. Two patients with pregnancy induced hyperemesis underwent a PEGJ in the 3rd and the 4th month of pregnancy, with the pregnancy being successfully brought to term and ending in vaginal deliveries. Carrying out a PEG permitted release from hospital and the programming of At Home Enteral Nutrition in 30 patients. With respect to the evolution of the patients, 22 patients have died during the course of the study. 18 patients remain in follow up in an ambulatory Enteral Nutrition program, and in the two patients with pregnancy induced hyperemesis, the PEGJ was removed after the pregnancy was successfully ended. There were no complications of any kind in 21 patients. The most common complication was the infection of the gastrostomy, which occurred in 13 patients. There was an accidental removal of the gastrostomy tube in 3 patients. In 3 cases there was an eversion of the gastric mucosa through the ostomy within the first 24-hours, and 20 days after the PEG respectively. In 2 cases there was an incarceration of the gastrostomy tube in the abdominal wall. Only two patients showed an important reflux of the gastric contents. There were no deaths as a result of PEG complications.

CONCLUSION

From our experience we can conclude the advantages of PEG as a long term nutritional support, showing a low incidence of complications, and the endoscopic technique has a zero mortality.

Esophageal obstruction by solidification of the enteral feed: a complication to be prevented

We report three cases of esophageal obstruction due to solidification of enteral feed refluxed from the stomach in patients being fed through a nasogastric tube. All three patients were administered sucralfate continuously by tube. The few previous descriptions of this rare complication have also implicated sucralfate with its pathogenesis. Given its clinical importance and the growing use of long-term enteral nutrition, this adverse event needs to be considered.

[Evaluation of energy metabolism in burn patients: indirect calorimetry predictive equations]

INTRODUCTION

Knowing the most reliable method for measuring the metabolic energy use (MEU), is of great importance in patients with severe burns. For the calculation of the energetic requirements of large burn patients, several predictive equations (PE's) are used, based on weight, size, age, body surface area (BSA), and burned body surface (BBS). Previous studies note the tendency for over-or underestimating the MEU, depending on whether one or another PE is used, which is why it is considered necessary to calculate the energy requirements in the most exact manner possible, which can be done by means of indirect calorimetry (IC).

MATERIAL AND METHODS

18 patients (14 men and 4 women) who were admitted to the Burn Unit between 1994 and 1995, were included in the study, with the following inclusion criteria; age > 18 years and < 65 years, and who presented deep burns on are than 15% of the body surface. The MEU of the patients was evaluated by means of IC, using a Deltatrac il unit. The MEU calculated by means of IC was compared with that calculated by means of the four most commonly used PE's in literature: Long Formula: MEU = Basal energy use (BEU) x activity factor x aggression factor which is variable according to the BBS; Curreri Formula: MEU = (Weight x 25) + (total BBS x 40); MEU = 2000 x BSA. As statistical methods, one looked for the existence of correlation, by means of the Pearson method, and the "r" were compared by means of the Fischer conversion. The regression coefficient was found among the values obtained through the PE's and those measured by IC, as well as among those of IC and the percentage of deep burn and the total burned body surface.

RESULTS

All the formulate included overestimated the MEU measured between 30.6% and 43.8% with the 2 x MEU formula being the one which did so least (30.6%). In any of them, there is an important variation of the percentage of overestimation with respect to the average MEU in this group. All are correlated in an important way with the MEU. The reliability of these PE's is variable, as is shown by the slopes of the regression lines, with the most reliable PE being that of 2000 x BSA, and that of 2 x MEU, by Harris-Benedict. There is also correlation between the average MEU by IC and the deeply burned body surface.

CONCLUSION

This study proves the usefulness of the IC for knowing the EME in burn patients, to prevent their hypernutrition, as well as the relative value of the formulae usually used clinically to estimate this parameter.

[Decrease of the incidence of sepsis syndrome after early enteral nutrition of patients with severe burns]

The objective of this study was to evaluate the effect of early enteral nutrition on the incidence of the septic syndrome as well as its tolerance, in patients with severe burns. We retrospectively studied 64 patients older than 15 years of age, with a greater than 20% burned body surface area. They were divided into 2 groups as a function of the time elapsed between the beginning of Enteral Nutrition and the time of the burning: 23 patients were given Enteral Nutrition within 24 hours after the burn, and in 41 patients the enteral nutrition was started later than 24 hours after sustaining the thermal injury. Both groups were similar with respect to age, sex, percentage of 2nd and 3rd degree burns, incidence of inhalation, and deaths. All patients received the Enteral Nutrition through a nasogastric tube, with administration of a polymeric, hyperprotein and hypocaloric formula through a continuous infusion pump. In our study we saw a reduction of the incidence of the septic syndrome in the patients who received early enteral Nutrition (26%; 6 patients of a total of 23), with respect to those who did non receive early Enteral Nutrition (54%; 22 patients of a total of 41), with a statistical significance of p > 0.05. There were no differences between both groups with respect to the digestive tolerance to Enteral Nutrition. From our study we can deduce that early Enteral Nutrition reduces the incidence of septic complications, without this increasing the digestive intolerance to the same.

Implications of a quasispecies genome structure: effect of frequent, naturally occurring amino acid substitutions on the antigenicity of foot-and-mouth disease virus

We provide evidence that the quasispecies nature (extreme genetic heterogeneity) of foot-and-mouth disease virus is relevant to the virus evading an immune response. A monoclonal antibody neutralizing the viral infectivity (clone SD6) recognizes an epitope located around a highly conserved sequence (amino acid sequence Arg-Gly-Asp-Leu-Ala at positions 141-145) in the capsid protein VP1 of foot-and-mouth disease virus of serotype C1. The amino acid substitutions Ala-138----Thr and Leu-147----Ile (or ----Val) reduced 100-fold the binding titer of monoclonal antibody SD6 to virions or to VP1. The effect of those substitutions was quantitatively reproduced with synthetic peptides representing the relevant sequences. This provides evidence that the two chemically conservative amino acids replacements--and not other substitutions present in the virus quasispecies--are responsible for the modified interaction with neutralizing monoclonal antibody SD6. The three substitutions were fixed in the viral capsid during one occurrence of foot-and-mouth disease and, furthermore, they are of a type found frequently among independent foot-and-mouth disease virus isolates. The results implicate the extreme heterogeneity of foot-and-mouth disease virus as an important element of viral pathogenesis.