Immunonutrition in the intensive care unit. A systematic review and consensus statement.
OBJECTIVE
To systematically review the effects of enteral nutrition with pharmaconutrients-enriched diets in critically ill patients and to establish recommendations for their use.


METHODS
Computerized bibliographic search of published research and citation review of relevant articles.


METHODS
Randomized clinical trials of critically ill patients treated with enteral nutrition comparing diets enriched with pharmaconutrients vs not enriched diets were included. Infectious complications and outcome variables (days on mechanical ventilation, ICU and hospital length of stay and mortality) were evaluated. Studies were classified in four subgroups according to the patient's primary diagnosis: surgical, trauma, burned or medical.


METHODS
A group of experts in methodology performed data extraction and statistical processes. A global analysis of the studies was done and also a separate study for each subgroup. Results of the meta-analysis were discussed within a 'clinical group' of clinicians with experience in the nutritional support of ICU patients, in order to find agreement about recommendations for the use of pharmaconutrients-enriched diets in critically ill patients.


RESULTS
Independent review of 267 articles identified 26 relevant primary studies. Global results indicate that there was a reduction in infection rate in the pharmaconutrition group, considering the appreciated lower incidence in abdominal abscesses (OR: 0.26, CI: 0.12-0.55) (P=0.005), nosocomial pneumonia (OR: 0.54, CI: 0.35-0.84) (P=0.007) and bacteremia (OR: 0.45, CI: 0.35-0.84) (P=0.0002). Also, patients treated with pharmaconutrition diets have a reduction in time on mechanical ventilation (mean 2.25 days, CI: 0.5-3.9) (P=0.009), ICU length of stay (mean reduction of 1.6 days, CI: 1.9-1.2) (P<0.0001) and hospital length of stay (mean reduction of 3.4 days, CI: 4.0-2.7) (P<0.0001). No effects were appreciated on mortality (OR: 1.10, CI: 0.85-1.42) (P=0.5). Nevertheless, the separate analysis for each subgroup showed that the reported beneficial effects were not the same for each patient population. Also, the clinician panel of experts identifies several problems in the published data about enteral pharmaconutrition in critically ill patients. In spite of the subgroup differences and of the problems detected, the clinician group considered that the appreciated results could support a Grade B recommendation for the use of these formulas in ICU patients.


CONCLUSIONS
Considering the beneficial effects and the absence of detrimental ones, the use of diets enriched with pharmaconutrients could be recommended in ICU patients requiring enteral feeding. Nevertheless, more investigation is needed in this field in order to find the more appropriate population of patients that can benefit from this nutritional therapy.
Montejo
Juan C
JC
Intensive Care Unit Hospital Universitario 12 de Octubre, Madrid, Spain.
Zarazaga
Antonio
A
López-Martínez
Jorge
J
Urrútia
Gerard
G
Roqué
Marta
M
Blesa
Antonio L
AL
Celaya
Sebastián
S
Conejero
Ramón
R
Galbán
Cristóbal
C
García de Lorenzo
Abelardo
A
Grau
Teodoro
T
Mesejo
Alfonso
A
Ortiz-Leyba
Carlos
C
Planas
Mercé
M
Ordóñez
Javier
J
Jiménez
Francisco J
FJ
D003422:Critical Care / Q000379:methods*; D016638:Critical Illness / Q000628:therapy*; D004750:Enteral Nutrition; D017052:Hospital Mortality; D006801:Humans; D007107:Immune System / Q000502:physiology; D007362:Intensive Care Units; D009747:Nutritional Physiological Phenomena; D017063:Outcome Assessment, Health Care; D016032:Randomized Controlled Trials as Topic