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Chapter 8
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To further individualise and thereby optimise nutritional support, (bio)markers involved in the
neuro-endocrine, immunologic/inflammatory and metabolic part of the stress response, could
be used to identify the onset of the different phases within each child. Due to the insufficient
sensitivity, specificity or availability of most (bio)markers, integration of several markers
combined with clinical characteristics might be most promising to optimise individualised
nutritional therapy in the PICU.
To investigate the effect of such a patient-tailored approach on short-, and preferably also
long-termclinical outcomes, clinical trials are needed to compare a strategy of marker-targeted
feeding with the current generally applied nutritional practices.
This information will add valuable evidence to current guidelines, that as of now do not
distinguishbetweenphaseofcriticalillness,severityofillnessanddiagnoses.Recommendations
derived from the high-level evidence provided by the PEPaNIC trial are also generally
applicable, but provide specific recommendations on provision of PN in respect to phase of
illness. Because recommendations on other aspects of nutritional support, such as enteral
caloric and macronutrient goals, should take these phases into account as well
51,82
(Chapter 1),
an update of current guidelines is urgently needed. Until other studies have provided evidence
to individualise nutritional support to disease and settings, these updated guidelines should
be used as a foundation for nutritional therapy, whilst considering the physiology of the
individual patient.
In the PEPaNIC trial, the strategy of withholding PN was limited to the period following PICU
admission. One might question if deterioration of clinical status beyond this period might
evoke a similar acute stress response and therefore if the child might benefit from parenteral
nutrient restriction as well. When more insight can be provided into the relation between the
stress response and the beneficial effects of late PN based on the PEPaNIC trial, application of
this strategy later during PICU stay might need to be investigated.
Finally, since we have shown that permissive parenteral underfeeding is beneficial early
in critical illness, avoidance of overfeeding has become even more significant. In order to
improve its detection, a new definition of overfeeding is urgently needed and should take into
account the age and nutritional status of the child, the phase of critical illness, and possibly
also the route of nutrition. However, to develop such a phase-dependent definition, adequate
identification of these phases is essential. In a subset of PEPaNIC patients, results from REE
measurements by IC will be analysed to gain more insight in the concept of overfeeding on
the PICU.
Other nutritional aspects in critically ill children that were beyond the scope of this thesis, but
in profound need of high-level evidence, are the optimal amount of EN early in critical illness