The impact of early enteral nutrition on 28-day mortality in septic shock: a cohort study

Enteral nutrition (EN) in septic shock patients is a double-edged sword. The impact of early enteral nutrition (EEN) on mortality in septic shock patients remains uncertain, and whether this association is modified by vasopressor dosage is also unclear.

The study aimed to investigate the association between EEN and 28-day in-hospital mortality in patients with septic shock and to explore whether the association varied across different dosages of vasopressors during the first 24 h.

Data were extracted from the Chinese Database in Intensive Care (CDIC). Adult septic patients who received vasopressors within 24 h of intensive care unit (ICU) admission were eligible for inclusion. The primary exposure was whether patients received early nutrition within the first 24 h after ICU admission (the EEN group). The primary outcome was 28-day mortality. Multivariate Cox regression models were employed to assess the association between the EEN group and 28-day mortality in the overall population and in patients receiving different vasopressor dosing intensity (VDI) levels. VDI was defined as the total vasopressor dose expressed in norepinephrine equivalents (NEEs), calculated as the time-weighted average over the first 24 h.

A total of 26,478 patients were screened and, ultimately, 1855 patients met the inclusion criteria. The median Sequential Organ Failure Assessment (SOFA) score was 11 [interquartile range (IQR): 8-14], and the Acute Physiology and Chronic Health Evaluation (APACHE) II score was 20 (IQR: 15-26). The 28-day in-hospital mortality rate was 19.7%. Compared to patients in the EEN group, those in the late enteral nutrition (LEN) group required higher vasopressor doses (8.7 vs. 10.6 ug/min, p<0.001) and had a higher 28-day mortality rate (16.6% vs. 21.1%, p = 0.03). After adjusting for confounding factors, EEN was not significantly associated with a reduction in the risk of 28-day mortality [Hazard ratio (HR) 0.832, 95% confidence interval (CI) (0.654-1.059), p = 0.135]. When stratified by VDI (norepinephrine equivalents), EEN exhibited a trend toward reduced 28-day mortality; however, this difference failed to reach statistical significance in patients with VDI < 15ug/min [HR 0.738, 95% CI (0.523-1.042), p = 0.084]. In contrast, EEN had no discernible impact on 28-day mortality risk in patients with VDI ≥ 15ug/min [HR 0.926, 95% CI (0.660-1.298, p = 0.655)].

Early enteral nutrition was not associated with a lower 28-day mortality risk in patients with septic shock, and it only demonstrated a trend in patients receiving low doses of vasopressors.