NUTRI-REAPED study: nutritional assessment of French critically ill children and nutrition practice survey in French-speaking pediatric intensive care units

Nutritional status at pediatric intensive care unit (PICU) admission is known to affect outcome in critically ill children. Impaired nutritional status is adversely associated with suboptimal outcomes (increased mortality, PICU length of stay, invasive ventilation duration, and rates of acquired infection) [1‐3]. Recent American guidelines [4] strongly recommend systematic nutritional status assessment within the first 48 h of PICU admission. This is recommended using a holistic approach [5], combining both static and dynamic measurements, and describing malnutrition in terms of its etiology, severity, mechanisms, chronicity, and impact on outcomes.

Critically ill children often have underlying chronic health conditions, which may in themselves impact on their nutritional status. Moreover, providing nutritional requirements can be challenging in this setting, resulting in nutrient deficits over the duration of PICU stay [1], which may induce in hospital malnutrition, and worsen outcomes. Identifying these children at risk is essential, in order to provide individualized nutrition support.

Large international PICU studies describing nutritional status at admission have been conducted [1, 6], but no published data exist in French-speaking PICUs. Therefore, to investigate this in a large number of French-speaking PICUs, of different types (medical, surgical or mixed, with various levels of training and concern about nutrition care) is important to gain a more accurate overview of baseline practices and to understand physicians and nurses’ knowledge in this area.

NutriSIP (the French-speaking PICU nutrition workgroup) is composed of dieticians, nurses, and physicians from some French-speaking countries (France, Belgium, and Switzerland) involved in PICU nutrition research and education. NutriSIP aims to improve nutritional practices among critically ill children. This study (the “Nutri-ReaPed study”) designed by NutriSIP aimed to describe the nutritional status of children admitted to French PICUs, by recruiting the majority of French PICUs through its network. In parallel, a survey whose aim was to describe PICU practices and knowledge around nutrition was sent to nurses [7] and physicians in the wider French-speaking PICU network. This was to describe compliance with current recommendations and guidelines and to compare knowledge between professional groups. The results of this study will serve as a base for NutriSIP to target its future educational interventions.

The Nutri-Reaped study involved three different, but related studies: (1) A PICU nurse survey about their local nutritional practices and knowledge, which was previously published [7]. (2) A PICU physician survey about their local nutritional practices and knowledge. (3) An observational point prevalence study assessing the nutritional status of critically ill children in France. This paper presents the results of the latter two studies. Both surveys were disseminated in seven French-speaking countries, while the observational study was conducted only in France, because of ethical permissions.

This is the first prospective study that reports nutritional status of children in pediatric intensive care units in France. The high PICU participation rate allowed for extensive analysis and reduces the risk of recruitment bias. Seasonal recruitment bias was also avoided by collecting data in three time periods. Undernutrition was diagnosed in 18.5% of the children, and those children were significantly younger. Additionally, in our survey, this is the first time that nurses and physicians’ knowledge and practices about nutrition have been compared in French-speaking PICUs. Physicians’ nutritional practices did not comply with international guidance, and their knowledge was inadequate in some areas, while significant differences were found between physicians and nurses’ accounts of local practices.

Undernutrition was frequent and those children were significantly younger. This needs to be taken into consideration by PICU healthcare professionals, as undernutrition is associated with suboptimal outcomes in this setting. This prevalence is higher than those undernutrition rates (10–15%) reported in hospitalized children around Europe (outside PICU) [13‐15].

Previous PICU studies showed undernutrition rates at admission ranging between 15 and 20% in Europe, and up to 65% in Brazil [2, 3, 16‐18]. These studies, however, were often single center and used different indices to define nutritional status (BMI, Waterlow indices, weight-for-age, height for age, etc.). Two recent international multicenter studies reported undernutrition rates at PICU admission (defined as a BMI z-score <  − 2SD) to be 17.1 and 17.9%, respectively [1, 19]. This is close to our results. However, these two studies did not take into account a potential seasonal bias. PICU admission diagnoses are highly seasonal, with respiratory disease prevalent in winter months [20]. This makes comparison with our study challenging. However, Nutri-Reaped study design was underpowered to identify any significant difference between the three time periods of recruitment.

Infants were more likely to be undernourished, as were children transferred from other units, which confirms the vulnerability of children with a medical history and of those with prior chronic conditions leading to PICU admission [21]. The BMI-for-age z-score was chosen to define nutritional status, as per WHO recommendations. Many other nutritional indices have been used in the literature, especially weight-for-age z-score, which does not require length or height for its calculation. However, such an index does not differentiate undernourished children from “short” stature children and should be interpreted and used with caution. Regarding BMI, like other indices, it will not differentiate lean children from those with undernutrition, and overweight children from those with a muscular body composition.

Faltering growth is a dynamic nutritional assessment recommended by Mehta et al. [5], but is rarely reported in the literature. This was not done in daily practice in most units, and this data cannot be retrospectively extracted from medical files or registries. Its assessment requires plotting values on an appropriate growth chart and the interpretation of this, which is time-consuming. These faltering growth and weight loss rates prior to PICU admission found in our study, are much lower than reported by Valla et al. [22] of 4.8% and 13.7%, respectively. This difference may be attributable to the single center design of the Valla et al. study (with potentially different population recruitment), or the less restrictive definition of growth faltering (weight-for-age curve presenting a deceleration of > − 1 z-score in the previous 3 months). However, faltering growth has also been identified in Valla et al. study as a risk factor for increased PICU length of stay and should be actively screened for at PICU admission.

An overweight status was diagnosed in 7.4% of children (BMI z-score > + 2 SD), which is lower than the 8.8–10% in the overall French pediatric population [23, 37]. This may be partly due to a higher prevalence of chronic medical conditions in patients admitted to PICU. Being overweight/obese has also been shown to be associated with suboptimal outcomes in various PICU studies while others found no impact. The obesity paradox described in adults is not yet clear so far in critically ill children with conflicting evidence [19, 24].

Finally, the physician’s subjective assessment of children’s nutritional status showed poor reliability compared to anthropometric measurements, especially in the undernourished subgroup, two-thirds of whom were inaccurately categorized as well nourished. This is consistent with previous studies which reported a limited correlation between objective nutritional assessment and subjective assessment, based on trained dieticians and on a detailed tool [25]. Therefore, this subjective assessment of nutritional status cannot be recommended.

The survey revealed the majority of PICU physicians considered nutrition support as a priority (even though this question within a nutrition survey may induce a bias). However, their knowledge about nutritional care was often inadequate, based on their reported practices, compared to current guidelines [4, 26]. Formal nutritional assessment was rarely undertaken and did not comply with the holistic approach recommended by Mehta et al. [5]. Previous work has shown specific PICU training program can be effective [27] to improve anthropometric measurement, and this should be disseminated in other PICUs.

International guidelines recommend that where possible energy requirements should be measured using indirect calorimetry (IC) [4]. However, this device is available in only 15% of PICUs worldwide [28]. Furthermore, a number of PICU clinical conditions prevent the use of IC (27% of patients), such as FiO₂ > 60%, air leaks, extracorporeal circulation [28]. Predictive equations, specifically Schofield, which are recommended when IC is not possible, were rarely used. In addition, recommended dietary allowances were followed, even though they are known to overestimate energy requirements in this setting, leading to potentially harmful overfeeding (Schofield equations correspond to healthy children’ resting energy expenditure and represent about 65% of recommended dietary allowance). NutriSIP aims to increase physician knowledge and awareness about the optimal method to calculate and prescribe energy goals.

Early enteral nutrition is the preferred administration route, according to current guidelines. However, reasons for withholding enteral nutrition varied between centers, and were not evidence based. [29, 30]. These large variations in responses from PICUs reflect the absence of guidance regarding many practical nutrition delivery issues. One example is the lack of any pediatric studies on prokinetic use in the PICU population. Additionally, the indications for and benefits of post-pyloric feeding on nutrition goal achievement in PICU remain unclear [31, 32]. Local written nutrition guidelines and local nutrition support teams would also help to improve nutritional practices within PICUs [33]. Early parenteral nutrition was standard practice in most PICUs, despite some recent evidence indicating this may be harmful. However, the survey was undertaken prior to the Pepanic trial publication [34]. NutriSIP aims to ensure that nutritional practices in PICU are based on sound evidence or logic, and this is achieved through education programs and future research in this field.

We found some differences and deficits between physicians’ and nurses’ knowledge and practices around nutrition in PICU children. Difference in the education level may explain part of these knowledge differences. However, nurses and physicians also have different roles and responsibilities regarding nutritional care. Physicians are responsible for the nutrition plan (prescription of nutritional support: feeding initiation timing, type of feed, route, and mode of feed delivery, energy, fluid, and protein goals), nurses are responsible for feed administration and feeding tolerance monitoring. Although these roles may sometimes overlap, it is interesting in our study that nurses and physicians sometimes responded differently to the same questions. This may reflect physicians lack of awareness of nursing practices around nutrition. Similarly, nurses frequently lacked awareness of the nutritional strategy planned by physicians. Written guidelines, multiprofessional nutrition rounds, and the continual auditing of practices would help reduce these differences between nurses and physicians. Yet, collaboration between nurses, dietitians, and physicians is essential in the PICU if we are to improve nutritional practices. Training needs to target all three professional groups, but around different areas of knowledge deficiency that is appropriate to their role and responsibilities.

A nutrition support team, consisting of all three professional groups may help achieving this goal. Nurses, especially, need to be engaged in and involved in protocol development, as they are responsible for nutrition delivery. Finally, we suggest review of local professional practices and regular clinical audits of practice after guidelines implementation, in order to ensure compliance with guidelines and direct quality improvement initiatives.

NutriSIP aims to disseminate evidence-based practices in the field of critically ill children nutrition, through research and education projects. NutriSIP will use this survey as a pre-intervention marker of nutrition knowledge and practices in PICUs, which will be reassessed in five years, using the same tool, to evaluate the impact of educational intervention. This intervention consists of an annual one-day free face-to-face teaching program, and open to any healthcare professional involved in PICU nutrition. In addition, various updates are provided in nutrition, at French-speaking pediatric and intensive care congresses. NutriSIP also helps in developing local nutrition guidelines, in order to help physicians setting nutritional goals, and improving nutrition delivery by avoiding unjustified interruptions to enteral nutrition.

This study has some limitations that warrant highlighting. Firstly, weight and height/length could not be measured in all patients; in these, an estimated value was used. This may have impacted on the BMI and other nutritional indices accuracy. Weight accuracy can also be questionable in the PICU setting as it may be influenced by fluid shifts. This may have led to an overestimation of patients’ weight and therefore potentially to an underestimation of undernutrition. Nutritional status definition was based on BMI-for-age z-score, as per WHO guidelines, but a holistic approach as defined by Mehta et al. [5] would be required to properly assess nutritional status, including a dynamic assessment, taking into account pathophysiology, etiology, chronicity and the impact of malnutrition. Anthropometric measurements are difficult to perform in the PICU setting: weighing children may be challenging because of PICU equipment (tubes, probes, mechanical ventilation) or considered unsafe; height cannot be measured respecting WHO guidelines in the bedbound child. This may have impacted on measurement accuracy. The diagnosis of faltering growth occurring prior to PICU admission may also be biased by the accuracy and validity of previous anthropometric measurements, performed outside the study. No data regarding outcomes were collected in the study, which did not allow us to assess the nutritional status impact on outcomes. Comparison between countries was not possible as the number of centers was too small in some countries (Switzerland, Lebanon, Algeria, and Canada). Other factors, such as differences in culture, access to healthcare or the geographical location may also have led to the differences in responses. Finally, there is always a risk of self-report bias in surveys, and responding staff was potentially proactive around PICU nutrition issues. Despite these limitations, we have undertaken the largest study of this type in French-speaking PICUs and have achieved a useful baseline upon which to target future interventions. Future research should address determining the optimal height measurement techniques in PICU children.

Undernutrition in children admitted to French-speaking PICUs is high, especially in infants and in children presenting with chronic underlying medical conditions. PICU professionals’ knowledge is often inadequate and international guidelines are not consistently followed. Assessing nutritional status at PICU admission and following a holistic assessment approach is the basis upon which to implement evidence-based nutrition goal setting to develop individualized nutrition plans. PICU healthcare professionals in French-speaking countries should benefit from increased targeted education and further collaboration, which is a key aim of the NutriSIP Group.