Transmyocardial laser revascularisation in acutely ischaemic myocardium

Objective: Although recent experience suggests that transmyocardial laser revascularisation (TMLR) relieves angina, its mechanism of action remains undefined. We examined its functional effects and analysed its morphological features in an animal model of acute ischaemia. Methods: A total of 15 pigs were randomised to ligation of left marginal arteries (infarction group, n=5), to TMLR of the left lateral wall using a holmium:yttrium-aluminium garnet (Ho:YAG) laser (laser group, n=5), and to both (laser-infarction group, n=5). All the animals were sacrificed 1 month after the procedure. Haemodynamics and echocardiography with segmental wall motion score were carried out at both time intervals (scale 0-3: 0, normal; 1, hypokinesia; 2, akinesia; 3, dyskinesia). Histology of the involved area was analysed. Results: Laser group showed no change of the segmental wall motion score of the involved area 30 min after the laser channels were made (score: 0±0). Infarction and laser-infarction groups both showed a persistent and definitive increase of the segmental wall motion score (at 30 min: 1.6±0.3 and 2±0, respectively; at 1 month: 1.8±0.2 and 1.8±0.4, respectively). These increases were all statistically significant in comparison with baseline values (P<0.5), however comparison between infarction and laser-infarction groups showed no significant difference. On macroscopic examination of the endocardial surface, no channel was opened. On histology, there were signs of neovascularisation around the channels in the laser group, whereas in the laser-infarction group the channels were embedded in the infarction scar. Conclusions: In this acute pig model, TMLR did not provide improvement of contractility of the ischaemic myocardium. To the degree that the present study pertains to the clinical setting, the results suggest that mechanisms other than blood flow through the channels should be considered, such as a laser-induced triggering of neovascularisation or neural destructio

Détection précoce de la malnutrition protéino-calorique: un atout thérapeutique

In the industrialised countries, the sedentary life and the ageing process of the population, as well as the more frequent chronic diseases and heavy treatments, increase the incidence of protein-energy malnutrition (PEM). The insidious nature and harmful outcome of the PEM on the recovery process requires careful attention of the practitioner to the clinical signs of PEM. Their detection includes an anamnesis, anthropometric examinations, and assessments of the nutritional intakes and the impact of disease and medico-surgical treatments. However, the loss of muscle mass, which is the main indicator of the PEM, is often only assessed by the measurement of the body composition using bioelectrical impedance analysis. The advantage of this method is to distinguish fat-free mass, including muscle mass, from fat mass, when the loss of muscle is hidden by an increase of fat mass and/or body water. Using these different tools allows the practitioner to early detect PEM, to identify its causes, and to establish an appropriate nutritional schedule, in order to prevent from PEM or correct it.La sédentarité et le vieillissement de la population, ainsi que les maladies chroniques et les interventions thérapeutiques lourdes toujours plus fréquentes, augmentent l'incidence de la malnutrition protéino-calorique (MPC) dans les pays industrialisés. Le caractère insidieux et les conséquences délétères de la MPC sur le processus de guérison requièrent l'attention du praticien aux signes d'alarme de la MPC. Leur détection inclut une anamnèse, des examens anthropométriques, une évaluation des apports nutritionnels, une appréciation de l'impact de la maladie et des traitements médico-chirurgicaux. Cependant, l'estimation de la fonte musculaire, le principal indicateur de la MPC, n'est souvent possible que par une mesure de la composition corporelle au moyen de la bioimpédance électrique. Cette technique permet de différencier la masse non grasse comprenant la masse musculaire, de la masse grasse, lorsque la fonte musculaire est masquée par une augmentation de la masse grasse et/ou de l'eau corporelle. L'utilisation conjointe de ces différents outils permet au praticien de détecter très tôt la MPC, d'identifier ses causes, et d'établir un programme nutritionnel approprié afin de prévenir ou corriger la malnutrition.</p

Ergonomic and economic aspects of total parenteral nutrition

Ergonomics in total parenteral nutrition include the work performed in the (hospital) pharmacy and on the medical ward. This article reviews the developments in total parenteral nutrition ergonomics and the related cost-savings

Precision and accuracy of bioelectrical impedance analysis devices in supine versus standing position with or without retractable handle in Caucasian subjects

Background & aims: Bioelectrical impedance analysis (BIA) could be facilitated in subjects who are able to stand by using scales without (BIAstd4) or with a retractable handle (BIAstd8), provided that they are as precise as BIA devices commonly used in the supine position in the hospital setting (BIAstd4). This observational prospective cross-sectional study aimed to compare the precision and accuracy of BIAstd4, BIAstd8 and BIAsup in a Caucasian population

Modulation de l'immunité chez le patient cancéreux: une arme à double tranchant?

Nutritional support of cancer patients should ideally contribute to improve the immune defence, maintain the protein body pool and sensitize the tumour to oncologic treatments. Such a goal is not easy to achieve, because any nutritional support efficient at stimulating immune response and protein syntheses might also simultaneously stimulate the tumour growth. Contradictory observations have been reported for several nutrients contained in the nutritive solutions available on the market. This is the case for glutamine, arginine, omega-3 fatty acids and nucleotides. Their clinical use during oncologic therapies deserves further testing and analysis.Le support nutritionnel d'un patient cancéreux devrait idéalement contribuer à améliorer sa défense immunitaire, maintenir ses réserves protéiques et sensibiliser la tumeur aux traitements oncologiques. Un tel objectif n'est pas aisé, car un support nutritionnel capable de stimuler la réponse immunitaire et la synthèse protéique pourrait se révéler à double tranchant, en stimulant également la croissance tumorale. Des résultats expérimentaux contradictoires ont été obtenus avec plusieurs nutriments contenus dans les solutions nutritives commercialisées. C'est le cas pour la glutamine, l'arginine, les acides gras omega-3 et les nucléotides. Leur utilisation clinique durant les traitements oncologiques mérite donc d'être davantage explorée et analysée.</p

Evaluation de l'état nutritionnel des patients admis aux urgences: contribution de la mesure de la composition corporelle

Weight and body mass index are used in clinical routine to detect malnourished patients. However, a study performed at the emergency admission of the University Hospital of Geneva shows that the prevalence of malnutrition is very underestimated when based on body mass index instead of fat-free mass. Indeed, a third of the patients with normal body mass index, i.e. between 20 and 24.9 kg/m2, present a fat-free mass under percentile 10. This suggests that the body mass index alone cannot be used as diagnostic criteria for malnutrition. This review describes the prevalence of malnutrition at the emergency admission of the University Hospital of Geneva, the prevalence of malnutrition in the literature and its relationship with length of hospital stay and mortality.Le poids et l'indice de masse corporelle sont utilisés de routine pour dépister les patients souffrant de malnutrition. Or, une investigation réalisée aux urgences de l'Hôpital Universitaire de Genève montre que la prévalence de la malnutrition est fortement sous-estimée si on se base sur l'indice de masse corporelle plutôt que sur la masse non grasse. En effet, un tiers des patients avec un indice de masse corporelle normal, i.e. entre 20 et 24.9 kg/m2, présentent une masse non grasse inférieure au percentile 10. Ceci suggère que l'indice de masse corporelle ne peut pas être utilisé comme seul critère diagnostique de la malnutrition. Cette revue décrit la prévalence de la malnutrition aux urgences de l'Hôpital Universitaire de Genève, la prévalence de la malnutrition dans la littérature et son lien avec la durée d'hospitalisation et la mortalité

Rôle de l'impédancemétrie dans le dépistage de la dénutrition

Nutritional status has a prognostic value in the clinical evolution of patients who are malnourished, are becoming malnourished or are in process of being rehabilitated. The evaluation of nutritional status is based on a comprehensive approach, and includes body composition measurement by bio-impedance analysis (BIA). BIA determines the quantity of body fat-free and fat mass and has a precision around 4%. The reliability of BIA depends on the use of body composition prediction equations that are adapted to the subjects studied and on the inclusion of various anthropometric parameters (weight, height, sex, age, race, etc). BIA remains imprecise in the presence of abnormal distribution of body compartments (ascites, dialysis, lipodystrophy) or of extreme weights (cachexia, severe obesity). Multi-frequency or segmental BIA were developed to overcome hydration abnormalities and variations in body geometry. However, these techniques require further validation. This review discusses the indications and limitations of BIA.L'état nutritionnel est un facteur pronostique de l'évolution clinique des patients dénutris, en voie de dénutrition ou de réalimentation. Son évaluation repose sur une approche globale, dont fait partie la bioimpédance électrique (BIA). Cette méthode évalue la répartition des compartiments corporels (masse grasse et non grasse) ; elle présente une reproductibilité d'environ 4%. Sa précision repose sur l'utilisation d'équations de prédiction intégrant plusieurs paramètres (poids, taille, sexe, âge, ethnie, etc) spécifiques aux populations étudiées. La BIA est imprécise lors de distribution anormale des compartiments corporels (ascite, dialyse, lipodystrophie, etc) ou de corpulence extrême (obésité sévère, cachexie). Le développement de mesures de BIA à fréquences multiples ou segmentaire vise à préciser les variations hydriques et géométriques. Ces techniques sont encore à valider. Cette revue évalue les indications et les limites de la BIA

Body composition in 995 acutely ill or chronically ill patients at hospital admission: a controlled population study

Objective: To determine if fat-free mass and fat mass in acutely ill and chronically ill patients differed from healthy controls at hospital admission and if prevalence of malnutrition differed by body mass index (BMI) or fat-free mass percentile. Subjects/setting: 995 consecutive patients 15 to 100 years of age admitted to the hospital were measured in the hospital admission center and compared with 995 healthy age-and height-matched subjects Design: Cross-sectional study. Fat-free mass, fat mass, and percentage fat mass were determined by 50 kHz bioelectrical impedance analysis. Prevalence of malnutrition was determined by BMI &lt; or = 20 kg/m2 or fat-free mass in the 10th percentile. Statistical analysis: Analysis of variance was used to examine differences between acutely ill and chronically ill patients and controls and between age groups. Results: Fat-free mass was significantly lower in patients than controls (P&lt; or = .05), and the difference with age in fat-free mass in patients was greater than the age-related difference in the controls. A higher percentage fat mass was found in spite of lower BMI in chronically ill patients older than 55 years. Among participants, 25% of acutely ill and 37.3% of chronically ill patients fell below fat-free mass in the 10th percentile, compared with 15.6% of acutely ill and 18.9% of chronically ill patients falling below BMI &lt; or = 20 kg/m2. Applications/conclusion: Weight and BMI do not evaluate body compartments and therefore do not reveal if weight changes result in loss of fat-free mass or gain in fat mass. In spite of minimal differences in BMI between patients and controls, we found that fat-free mass was lower and fat mass was higher in acutely ill and chronically ill patients than controls. The objective measurement of body composition, as part of a comprehensive nutritional assessment, helps to identify subjects who have low fat-free mass or high fat mass.</p

Physical characteristics of total parenteral nutrition bags significantly affect the stability of vitamins C and B1: a controlled prospective study

Background: Vitamin degradation occurring during the storage of total parenteral nutrition (TPN) mixtures is significant and affects clinical outcome. This study aimed to assess the influence of the TPN bag material, the temperature, and the duration of storage on the stability of different vitamins. Methods: Solutions of multivitamin and trace elements at recommended doses were injected into either an ethylvinyl acetate (EVA) bag or a multilayered (ML) bag filled with 2500 mL of an identical mixture of carbohydrates (1200 kcal), fat (950 kcal), and amino acids (380 kcal). The bags were then stored at 4 degrees C, 21 degrees C, or 40 degrees C. Concentrations of vitamins A, B1, C, and E were measured up to 72 hours after compounding, using high-pressure liquid chromatography. Results: Ten percent to 30% of vitamin C degradation occurred within the first minutes after TPN compounding. Vitamin C was more stable in ML bags (half-life: 68.6 hours at 4 degrees C, 24.4 hours at 21 degrees C, and 6.8 hours at 40 degrees C) than in EVA bags (half-life: 7.2 hours at 4 degrees C, 3.2 hours at 21 degrees C, and 1.1 hour at 40 degrees C). Moreover, appearance of dehydroascorbic acid in the TPN mixture did not compensate for vitamin C losses. Vitamin B1 was stable at 21 degrees C, but a 43% loss occurred at 40 degrees C after 72-hour storage in EVA bags. The other vitamins were stable in the TPN mixture stored in both bags at any temperature and without daylight protection. Conclusions: Degradations of vitamins C and B, are significantly reduced in ML bags compared with EVA bags. To prevent vitamin C deficiencies, its initial dose should be adapted to its degradation rate, which depends on the TPN bag material, the ambient temperature, and the length of time between TPN compounding and the end of infusion to the patient.</p