The critical care community still has mixed feelings when considering the optimal nutrition of intensive care unit (ICU) patients, which is understandable as randomized controlled trials have not been very helpful in improving clinical practice. There have been no randomized controlled trials (RCTs) to contribute to the discussion, especially concerning the role of enterally fed protein in optimal critical care. Recent studies on the route of feeding have shown that enteral nutrition (EN) is not necessarily superior to parenteral nutrition (PN) [1, 2]. There appears to be a strong consensus, with backup from a meta-analysis, on the preferential use of EN over PN [3]. The infection rate was especially used as an argument; however, this is not substantiated in recent trials [1, 2]. We have to consider how applicable this current knowledge is to all ICU patients. Early EN is still the preferred way of feeding [3]. Starting feeding early may improve the outcome of ICU patients. RCTs have all investigated (supplemental parenteral) energy delivery [4]. Only two trials have ‘considered’ protein: the PERMIT trial [5] (protein supplemented, equal level) and EAT-ICU trial [6] (protein supplemented, higher level). Early energy delivery should be applied cautiously since it appears to be related to worse outcome in ICU patients [7, 8, 9]. Therefore, and from the perspective of clinical practice, the Swiss Supplemental PN (SPN) trial appears to provide the most logical design [10]—start with early EN and evaluate on day 3 what the level of energy delivery is; when delivery levels are low (< 60%) start supplementation PN. In clinical practice in our ICU the enteral feeding levels are high enough to avoid PN supplementation, which therefore restricts the specific indication to use PN. The focus of this research has been caloric delivery. There are more than enough observational data to support that higher protein delivery is associated with improved outcome in ICU patients [7, 8, 9]. These observational studies clearly show the benefit of higher protein delivery. However, they are considered relatively weak evidence since illness is considered a confounding factor in the relationship between delivery and outcome for which we cannot completely adjust. Randomized trials have not been conducted, although two trials with randomized high(er) amino acid infusion are available and somewhat contradicting [11, 12]. As with the studies on caloric delivery, the studies on protein have been hampered by insufficient knowledge on energy and protein metabolism under these (patho)physiological circumstances in the ICU patient [7, 8, 9]. Therefore, mechanistic studies on the protein physiology in ICU patients is an essential and current development. The Swedish group of Wernerman and Rooyackers has provided crucial information on the topic. They showed that it was possible to change protein balance during the early phase of admission to the ICU from negative to positive by a short-term (3-h) high-level (1 g/kg/day) amino acid (AA) infusion [13]. This observation was very important to help understand the physiology since it showed that, under these circumstances of critical illness, some basic principles of nutrition still perform well. In the December 2017 issue of Critical Care, Sundstrom et al. showed that the effect of supplemental AA infusion at 3 h is still present at 24 h [14]. Why is this so important to know? We know from extensive studies in sports and the elderly that protein synthesis can be stimulated by bolus protein feeding; however, we know relatively little about the effects of continuous (low dose per time unit) feeding. While the absolute levels of protein balance still have to be considered with caution (e.g., choice of tracer), and we are not completely sure where the protein is going, we now know this positive effect on protein balance is lasting. The next challenge is to reconnect this physiological information with the outcome of ICU patients. We have shown that muscle (protein) mass at admission to the ICU is relevant for the outcome of ICU patients [15]. We do not know if we can change muscle mass and outcome of ICU patients with protein nutrition. The study by Sundstrom et al. [14] is very promising for protein balance, but will that be enough to change outcome? And, if so, is that true for all patients—does one size fit all? The ICU patient group is heterogeneous. Earlier, we found high protein delivery to be associated with lower mortality, except for sepsis patients and patients with early caloric overfeeding [7]. The EAT-ICU trial did not find an effect of early goal-directed feeding on physical component score at 6 months or on mortality [6]. Goal-directed feeding included feeding energy based on indirect calorimetry and protein up to 1.5 g/kg/day from day 1. Feeding calories up to the measured caloric target from day 1 may be equal to caloric overfeeding [7]. The 47% of patients with sepsis in the EAT-ICU trial might also not benefit from the higher protein feeding [7]. Therefore, the effects of protein and energy cannot be assessed individually from this trial. Ferrie et al. showed interesting differences in muscle mass and function between an AA infusion rate of 0.8 and 1.2 g/kg/day [12], but not all patients are equal—one size does not fit all! Those patients with a low protein reserve (low muscle mass) may be at highest risk in the ICU and may benefit more from intervention with early protein nutrition. We have to await further studies, including randomized studies and post-hoc observational studies, to further develop this area of interest. The studies trying to understand the mechanism behind the physiological effect are important as well; we might come nearer to the truth of what works and what does not work in ICU nutrition.
Muscle fiber-type specific expression of UCP3-protein is reported here for the firts time, using immunofluorescence microscopy
Abstract: INTRODUCTION: Early protein and energy feeding in critically ill patients is heavily debated and early protein feeding hardly studied.
The European eel (Anguilla anguilla) is a delicacy fish and an integral part of the Dutch culinary history. However, the stock of adult eel has decreased significantly due to a precipitous recruitment of glass eel fall. This relates to multiple factors including obstacles in migration pathways, loss of habitat and chemical pollution. Consequently, Anguilla anguilla has become a critically endangered species and is protected under European legislation. One possible solution, explored on laboratory scale, is the captive reproduction of eels and growth of glass eel in aquaculture. A big challenge of this technique is the limiting aspect of possible nutrients for the eels in the larval stage, as the diet must be delivered in micrometric capsules (< 20 µm) with a high protein content. Such diets are not yet available on the market. Electrohydrodynamic atomization (EHDA) is a novel option to prepare a micro-diet suitable for eel larvae. EHDA is especially interesting for its narrow size distribution capabilities and for applications which require submicrometric sizes. This project aims to evaluate the use of EHDA to produce high protein content micrometric size capsules for feeding larval eels. If successful, this would assist in the captivity production of glass eel and to make the eel culture independent of wild catches, restoring the culinary market. The project will be conducted in two phases. Firstly, tests will be conducted to evaluate the necessary conditions of the capsules using EHDA. Subsequently, the obtained capsules will be tested as feed for eel larvae. The main objective is to favour the development of a more sustainable eel culture, regarding the possibilities of investigating the current fish in natura option and exchanging it for a captivity one.
Circular agriculture is an excellent principle, but much work needs to be done before it can become common practice in the equine sector. In the Netherlands, diversification in this sector is growing, and the professional equine field is facing increasing pressure to demonstrate environmentally sound horse feeding management practices and horse owners are becoming more aware of the need to manage their horses and the land on which they live in a sustainable manner. Horses should be provided with a predominantly fibre-based diet in order to mimic their natural feeding pattern, however grazing impacts pasture differently, with a risk of overgrazing and soil erosion in equine pastures. Additionally, most horses receive supplements not only with concentrates and oils, but also with minerals. Though the excess minerals are excreted in the manure of horses, these minerals can accumulate in the soil or leach to nearby waterways and pollute water resources. Therefore, the postdoc research aims to answer the main question, “What horse feeding practices and measurements are needed to reduce and prevent environmental pollution in the Netherlands?” The postdoc research is composed of two components; a broad survey-based study which will generate quantitative data on horse feeding management and will also obtain qualitative data on the owners’ engagement or willingness of horse owners to act sustainably. Secondly, a field study will involve the collection of detailed data via visits to horse stables in order to gather data for nutritional analysis and to collect fecal samples for mineral analysis. Students, lecturers and partners will actively participate in all phases of the planned research. This postdoc research facilitates learning and intends to develop a footprint calculator for sustainable horse feeding to encompass the complexity of the equine sector, and to improve the Equine Sports and Business curriculum.
