American journal of respiratory and critical care medicine vol:187 issue:3 pages:247-255
Rationale Early parenteral nutrition to supplement insufficient enteral feeding during intensive care (early-PN) delays recovery as compared with withholding parenteral nutrition for one week (late-PN). Objectives To assess whether deleterious effects of early-PN relate to severity of illness or to the dose or type of macronutrients. Methods Secondary analyses of a randomized controlled trial (EPaNIC; N=4640) performed in seven ICUs from three departments in two Belgian hospitals. In part-1, all patients were included to assess the effect of the randomized allocation to early-PN or late-PN in subgroups of patients with increasing upon-admission severity of illness. In part-2, observationally, the association of the amount and the type of macronutrients with recovery was documented in those patient cohorts still present in intensive care at day 3, 5, 7, 10 and 14. Measurements The primary endpoint was time-to-alive-discharge from ICU. For part-1, also a secondary endpoint, acquisition of new infections, was analyzed. All statistical analyses were performed with uni-variable and adjusted multivariable methods. Main Results In none of the subgroups defined by type or severity of illness, a beneficial effect of Early-PN was observed. The lowest dose of macronutrients was associated with the fastest recovery and any higher dose, administered parenterally or enterally, was associated with progressively more delayed recovery. The amount of proteins/amino-acids rather than of glucose appeared to explain delayed recovery with early feeding. Conclusions Early combined parenteral/enteral nutrition delayed recovery irrespective of severity of critical illness. No dose or type of macronutrient was found to be associated with improved outcome. Clinical trial registration information available at www.clinicaltrials.gov, i.d. code NCT00512122.