Nutritional strategies for noninvasively ventilated critically ill patients: results from the NUTRINIV retrospective study

The ideal nutritional strategy for patients on noninvasive ventilation (NIV) remains uncertain. This study assessed the nutritional management of intensive care unit (ICU) patients undergoing NIV, evaluating discrepancies between actual intake and recommended targets. Associations between different nutritional modalities and patient outcomes were also analyzed. This retrospective study analyzed electronic records of adults undergoing NIV for more than two days in the ICU from March 1, 2020, to February 1, 2023. Data included nutritional management, NIV settings, and patient outcomes. Daily caloric and protein gaps were calculated as the difference between actual intakes and targets determined using the ESPEN stepwise approach. Descriptive statistics and tests were used to assess differences in nutrition modality. Univariable and multivariable Cox regression models were applied to examine associations between nutritional variables and outcomes. Records from 92 patients (62 males, 67%) with a median (Q1; Q3) age of 67 (59; 75) years were analyzed. Nutrition began a median of 1 (0; 2) day after NIV initiation and lasted for a median of 4 (2; 8) days. Enteral nutrition (EN) was provided to 10% of patients, parenteral nutrition (PN) to 43%, and both modalities to 23%, while 24% received oral nutrition. Median caloric intake in the ICU was 8.9 (4.2; 11.8) kcal/kg/day, and protein intake was 0.4 (0.1; 0.5) g/kg/day. Although mean (SD) daily caloric intake increased from 102.9 (257.7) kcal on day 1 to 726.2 (597.6) kcal on day 8, up to 90% of patients still failed to meet the recommended caloric intake targets. Patients on PN or combined nutrition achieved higher caloric and protein intakes but were associated with longer NIV durations (p < 0.001). Multivariable analysis showed that the peak daily caloric intake during ICU stay was independently associated with lower ICU mortality. This study highlights that critically ill patients undergoing NIV received sub-target caloric and protein intake, despite early initiation of nutritional support. Patients receiving PN or combined modalities achieved higher nutritional intakes but had longer NIV durations. An association was observed between higher peak daily intake and lower mortality, but not between days below target and adverse outcomes. ClinicalTrials.gov NCT06260202 registered on January 29, 2024.