Interest of conventional clinical, biochemical and bioimpedance measurements as indicators of mortality risk in critical patients

Risk assessment is nowadays an essential part of the management of seriously ill subjects, and multiple scoring methods are available, based on single or preferably multiple determinations. Some of these protocols have been successfully used around the world, and they permit the prediction of outcomes in different clinical populations. However, many indices are labor-intensive or demand an expanded set of biochemical determinations, thus representing an economical burden. Aiming to evaluate the prognostic value of ordinary variables that are already present in the clinical observation, 50 consecutive patients admitted at the intensive care unit were prospectively documented. Methods included clinical (age, sex, stay in ICU, FIO2), biochemical (serum albumin, hemoglobin, glucose, creatinine, WBC count), and bioimpedance variables (resistance, reactance, body impedance coefficient). All these values were registered at admission and before discharge or death, and compared with survival rate. Initially only WBC count was significantly different in survivors, but ongoing documentation revealed that later on, four indices were endowed with prognostic impact: serum album, glucose levels, WBC count and FIO2 requirements. Organ or function-sustaining procedures were also associated with outcome, nominally mechanical ventilation, vasoactive drugs, and enteral/parenteral nutrition. Furthermore, patients submitted to two or three of these methods exhibited higher mortality than those receiving just one, with even better result for those not requiring any. It is concluded that observation of ongoing changes in conventional clinical variables available in the clinical chart are a valid means of estimating the mortality risk in critical cases.

[Assessment of body composition in pregnant women at term]

BACKGROUND

Pregnancy is associated with well-known physiologic changes of maternal fluid and energy compartments, along with organ hypertrophies and the appearance of fetal and placental tissues. As a consequence, body composition is modified, but this phenomenon has not been well documented. The advent of bioimpedance has contributed to the documentation of the desired information in a safe and practical way.

AIMS

The aims of this study were: To register the principal anthropometric variables in a population of pregnant women at term; To determine body composition by bioimpedance analysis; To compare these findings with the former results, as well as with other assessment procedures reported in the literature.

PATIENTS AND METHOD

The population consisted of 30 pregnant women at term admitted for delivery, without complications, fetal distress or multiple pregnancy, and submitted to the following measurements: Anthropometry--Weight, height, body mass index, triceps skinfold, arm muscle circumference; Bioimpedance analysis--Body fat, lean body mass, total water, intra and extra-cellular water, third space, and exchangeable Na/K ratio.

RESULTS

Body weight and body mass index were increased but within the expected values for these patients. Total body water was similar to results in non-pregnant women when expressed as percentage, in accordance with other studies, but with a trend toward increase in the extracellular compartment and presence of third space fluid. Body fat was elevated, but the proportions were not much different from previous anthropometric surveys.

CONCLUSIONS

In the conditions of this investigation, in which a bioimpedance equation for general use was employed, the method indicated results that were consistent with the clinical course, anthropometric documentation, and the findings of other groups. It is concluded that bioimpedance analysis compares favorably with other assessment procedures in pregnancy, and further studies with this method should be undertaken.

Measurement of body composition changes during hemodialysis by bioimpedance analysis

Monitoring of fluid exchanges during hemodialysis is essential for the safety and efficacy of the procedure. Bioimpedance analysis has been used for the measurement of body compartments in many settings, but experience during hemodialysis is relatively scare. In a prospective study of 28 cases of chronic renal failure treated by long-term hemodialysis on an outpatient basis, body composition studies were done immediately before and after the dialysis session. Methods included body weight, serum albumin, hematocrit, hemoglobin, sodium and osmolality. These variables were compared with impedance (BIA) findings, namely lean body mass, body fat, total water, extra and intra-cellular water, third space, and exchangeable sodium/potassium ratio. Patients lost weight and improved hematocrit, hemoglobin, osmolality and serum sodium during the therapy, and BIA measurements were consistent with these changes. Lean body mass and body fat markedly changed along the dialysis session (respectively -24.5% and + 7.5%), and these results were out of proportion regarding known gains and losses in that period. It is concluded that BIA was useful for monitoring water fluxes during hemodialysis, but provided unreliable information about body fat and lean body mass.

Preoperative assessment in cases of adult megacolon suffering from moderate malnutrition

Acquired megacolon is a chronic disease associated with constipation and malnutrition. Surgical treatment may be required for the alleviation of the intestinal symptoms, emphasizing the interest of nutritional assessment in this population. In a prospective study of 33 patients suffering from acquired megacolon and requiring either anterior resection or pull-through operation, standard anthropometric and biochemical measurements as well as the PNI of Buzby and Mullen were preoperatively assessed. Mean age of the population was 49 +/- 13 y, with 17 males and 16 females. The combined nutritional score indicated 63.6% of the population were malnourished (21/33) of the patients, whereas the Prognostic nutritional index (PNI) revealed 3 high-risk cases (9.1%), 9 with moderate risk (27.3%), and reduced risk for all others. Indeed, 39.4% (13/33) of the patients displayed surgical or septic problems. Chi-square analysis confirmed that both studied criteria were significantly associated with complications (p < 0.05), as morbidity was restricted predominantly to cases with unfavorable Prognostic nutritional index (PNI) results or clear signs of nutritional deficit. Both PNI and conventinoal nutritional assessment are valuable tools for the screening of these surgical candidates. Artificial alimentation was not used in this experience, but deserves consideration in selected patients. Nutritional status improved in the late postoperative period, with normalization of bowel function.

Hematologic disorders in trauma patients during parenteral alimentation with lipids

Total parenteral nutrition with lipids is a well-accepted modality of metabolic support in seriously ill trauma patients. Intolerance to lipid administration is unusual when dosage limits are not exceeded, and few hematologic disturbances have been recorded with modern fat emulsions. In the course of intravenous alimentation of six adults admitted for traumatic lesions, eosinophilia with or without leukocytopenia was noticed after periods of four days to five weeks. Principal clinical events and hematologic derangements were documented in this population. Sepsis was not always present in the patients by the time of the complication, and in those that did require antibiotics and other drugs, the prescription remained unchanged along the episode. Discontinuation of the nutritional regimen with lipids was followed by normalization of the hematologic profile, suggesting that an acute or sub-acute allergic reaction was responsible. The appearance of skin rash in two occasions reinforces this hypothesis, and the possibility of hemophagocytosis merits consideration in two of the cases who displayed reversible acute leukocytopenia. It is concluded that blood cell aberrations are possible during intravenous feeding with lipids in trauma subjects, but tend to respond to suppression of the lipid-containing nutritional prescription.

[Nutritional assistance to patients during radiotherapy]

With the aim of assessing the possible benefits of nutritional therapy, 140 patients were prospectively studied during radiotherapy of the head and neck (81%) and esophageal cancer (19%). Mean age was 56.0 (17-80), with 114 males and 26 females. Duration of both nutrition and radiotherapy was 78.0 +/- 45 days. Tube feeding was the primary modality in 50.7% of the population, and oral regimens in the remaining 49.3%, but associations between the methods were also used. Enteral diets were supplied under the supervision of a specialized tem for home alimentation (PROSNED). Compliance to the program was 100%, and a lymphocyte count diminished along this period (1933 +/- 1033 vs 1265 +/- 688, p. 0.001). A subjective improvement was reported by 84% of the population, and total calorie intake, that was below 60% of estimated needs in 100% of the cases initially, significantly improved to just 40% inadequate at the end of the observations. Radiotherapy was associated with mucositis in 21% of the patients, taste changes in 79%, xerostomy in 81%, anorexia in 66% and odinophagia in 59%. In the individuals selected for enteral feeding, side-effects were represented by technical problems (20%) and gastrointestinal disorders (13%). All patients completed the nutritional support program and there was no mortality in this series. It is concluded that; 1) Early nutritional support during radiotherapy was able to maintain or improve the nutritional status; 2) Tube feeding, alone or in combination with oral diets, was indicated whenever appropriate and contributed to fulfillment of the energy requirements; 3) Reduction of total lymphocytes could not be prevented by the mentioned therapy; 4) Complications of enteral alimentation were mild and affected a small proportion of the population; 5) Troubles induced by radiotherapy were as frequent as expected, and tended to disturb the intake of food; 6) The compliance to the therapeutic plan was excellent and can be attributed to the efforts of the multidisciplinary team as well as to the help of the specialized home alimentation unit (PROSNED): Diet therapy. Cancer. Nutritional assessment. Radiotherapy. Nutritional support.

[Iron-deficiency anemia in enteral nutrition: correlation with tube position]

Enteral alimentation is a commonly employed procedure for pre-operative rehabilitation and nutritional maintenance of depleted patients suffering from esophageal diseases. In a prospective study of 61 cases exhibiting benign (n = 38) and malignant (n = 23) conditions, a commercial polymeric diet was supplied in the proportion of 40 Kcal/kg/day during at least two weeks. The liquid preparation was infused by bolus technique at home, by the patients themselves, via nasogastric (n = 25) or nasoduodenal silastic tube (n = 36). Total food intake, that before treatment had been under 60% of estimated requirements, reached the expected range throughout the therapeutic period, and also iron input was adequate (0.3 mg/kg/day). Standart anthropometric and biochemical assessment of these cases, with included serum iron and hemoglobin concentration, indicated stabilization of general nutritional parameters, but with persistence of moderate anemia(hemoglobin 12.6 +/- 2.0 g/dl; iron 59.2 +/- 35.7 mg/dl). Stratification of the population according to enteral tube position demonstrated similar diagnoses and clinical conditions for both groups. Mean initial iron and hemoglobin concentration was also the same, but final serum iron was increased after gastric administration (p < 0.05) and diminished with duodenal diet (p < 0.05). It is concluded that: home enteral nutrition in malnourished patients with esophageal diseases is consistent with an acceptable nutritional status, but without significant recovery from anemia, serum iron in this population only increases after intra-gastric alimentation; it is probable that this last finding is related to impaired ionization and absorption of dietary iron, when food is introduced in a postpyloric site.

[Cardiovascular effects of arginine and nitric oxide]

Amino acids are an unusual chemical category because they are endowed with alimentary properties, but at the same time they may determine typical pharmacologic responses in some circumstances. These facts were responsible for the origin of modern pharmaconutrition, which has been using arginine for some time because of its beneficial impact on immune function, nitrogen anabolism and wound healing. The recent identification of its metabolite NO (nitric oxide), a powerful mediator related to a large number of physiologic and pathophysiologic phenomenons, has augmented the interest for this amino acid.

[Comparative study of arginine and glutamine supplements in malnourished surgical patients]

Protein-calorie malnutrition is frequently diagnosed in patients with serious digestive conditions displaying obstructive symptoms, notably in esophageal cancer. In the present study a homogeneous group of subjects affected by esophageal cancer and candidates for elective surgery was randomly treated by one of the following oral supplements: arginine (group I), glutamine (group II), or mixed commercial amino acids (Group III-controls). The methods included nutritional measurements (biochemical and anthropometric assement), immunologic survey (skin tests), and general clinical and surgical findings, with emphasis on surgical morbidity. Body weight remained stable throughout the study, whereas serum albumin, total lymphocytes and skin tests tended to improve in all groups, with statistical confirmation for albumin in arginine-treated cases (group II). Post-operative hospitalization was numerically shorter during glutamine supplementation, and this trend was statistically significant when total morbidity was compared between the groups. It is concluded that: 1) Malnutrition and anergy were a major problem in this population, with equally severe post-operative morbidity; 2) Administration of arginine enabled serum albumin levels to improve; 3) Glutamine-treated subjects displayed reduced post-operative morbidity; 4) No side effects could be attributed to the therapy here employed.

[Nutritional support, free radicals, and antioxidants]

Antioxidants and free radical scavengers are molecules endowed with the ability of neutralizing reactive oxygen species that may accumulate in the organism during various pathologic processes. In circumstances of peroxidation of lipids and damage to enzymatic chains, cell membranes and other structures may be followed by functional losses and even cell death. Many antioxidants are normal constituents of the diet in the form of vitamins, trace elements and amino acids, and other useful properties cannot be easily distinguished from their free-radical scavenging abilities. Much controversy surrounds also the indications of these substances, both for prophylactic and therapeutic purposes. The first large-scale population studies have only recently been arranged, and additional investigations are required in many promising areas, including cancer patients undergoing chemo and radiotherapy.

[Infections of central venous catheters]

The central venous catheter is considered the lifeline of patients requiring long-term parenteral nutrition, and its infectious complications accordingly represent a frequent cause for hospitalization and morbidity. Modern catheters made of Silastic increase the duration and efficiency of venous access, but their substitution is also more complex and expensive. In a small series of patients undergoing home parenteral nutrition due to short bowel syndrome, and carrying. Silastic catheters, infection of the cannula was treated by administration of systemic as well as local antimicrobial agents. The septic process was resolved without the need of removing the catheters, and with excellent tolerance to the medications. It is concluded that in-situ sterilization of long-term catheters should be attempted in selected cases.

Gastric mucosal injury after hepatic arterial infusion chemotherapy with floxuridine. A clinical and pathologic study

BACKGROUND

Hepatic arterial infusion chemotherapy (HAIC) of liver metastases of colon cancer with an implantable pump is associated with liver and gastrointestinal complications.

METHODS

The authors retrospectively studied the clinical features and gastric histopathology of nine patients who received HAIC and had gastritis develop and in whom biopsy specimens were available.

RESULTS

Gastritis was heralded in these patients by epigastric pain and tenderness, nausea, vomiting, weakness, and anorexia. In seven patients, 18 gastric ulcers were endoscopically detected. Mucosal damage developed despite prophylactic antiulcer therapy and healed only upon cessation of HAIC. These observations suggest that the predominant drug given, floxuridine, was the responsible toxic agent. Seventeen biopsy specimens were reviewed, and all exhibited varied histologic evidence of inflammation, reactive glandular changes, and cell necrosis. These mucosal changes were present even in tissues obtained from patients without ulcers. In addition, floxuridine-induced glandular atypia was noted in eight biopsy samples from six patients. The crowded glands were distorted and lined by large cells that included bizarre forms with pleomorphic nuclei.

CONCLUSIONS

Gastric injury in HAIC appeared analogous to the general features encountered in reactive gastritis resulting from chemical irritants. The glandular atypia is peculiar to HAIC, and although the changes were morphologically alarming, in this clinical situation care should be exercised not to interpret floxuridine-induced atypia as carcinoma.

[The prognostic value of cholesterol levels in malnourished patients with esophageal carcinoma]

A variety of clinical calculations, including serum cholesterol, have been used as parameters of prognostic value in surgical populations, but there are few studies aimed at patients with esophageal carcinoma. In a set of patients with established esophageal cancer, cholesterol and triglyceride levels were recorded, along with the following parameters: age, sex, body weight, serum albumin, total lymphocytes, and hemoglobin concentration. Manual grip strength was measured, along with delayed cutaneous hypersensitivity response, and the type of surgical treatment was distinguished (palliative versus radical). Total complications and postoperative hospitalisation time are the main indicators used in our study for the surgical results. Patients were divided into two groups: those with serum cholesterol levels over 150 mg/dl (Group I) and those under that figure (Group II). Most nutritional and functional values were lower in Group II patients, for whom the radical surgery rate was also lower, with greater postoperative morbidity. It was concluded that 1): Cholesterol depletion is associated with nutritional and immunological alterations and 2) post-surgical results are poorer in patients with levels below 150 mg/dl.