Gastrointestinal dysfunction during enteral nutrition delivery in intensive care unit (ICU) patients: Risk factors, natural history, and clinical implications. A post-hoc analysis of The Augmented versus Routine approach to Giving Energy Trial (TARGET)

BACKGROUND: Slow gastric emptying occurs frequently during critical illness and is roughly quantified at bedside by large gastric residual volumes (GRVs). A previously published trial (The Augmented versus Routine approach to Giving Energy Trial; TARGET) reported larger GRVs with energy-dense (1.5 kcal/mL) compared with standard (1.0 kcal/mL) enteral nutrition (EN), warranting further exploration. OBJECTIVE: To assess the incidence, risk factors, duration, and timing of large GRVs (≥250 mL) and its relation to clinical outcomes in mechanically ventilated adults. METHODS: A post-hoc analysis of TARGET data in patients with ≥1 GRV recorded. Data are n (%) or median [IQR]. RESULTS: Of 3876 included patients, 1777 (46%) had ≥1 GRV ≥250 mL, which was more common in males (50 compared with 39%; P < 0.001) and in patients receiving energy-dense compared with standard EN (52 compared with 40%; RR = 1.27 (95% CI: 1.19, 1.36); P < 0.001) in whom it also lasted longer (1 [0–2] compared with 0 [0–1] d; P < 0.001), with no difference in time of onset after EN initiation (day 1 [0–2] compared with 1 [0–2]; P = 0.970). Patients with GRV ≥250 mL were more likely to have the following: vasopressor administration (88 compared with 76%; RR = 1.15 [1.12, 1.19]; P < 0.001), positive blood cultures (16 compared with 8%; RR = 1.92 [1.60, 2.31]; P < 0.001), intravenous antimicrobials (88 compared with 81%; RR = 1.09 [1.06, 1.12]; P < 0.001), and prolonged intensive care unit (ICU) stay (ICU-free days to day 28; 12.9 [0.0–21.0] compared with 20.0 [3.9–24.0]; P < 0.001), hospital stay (hospital-free days to day 28: 0.0 [0.0–12.0] compared with 7.0 [0.0–17.6] d; P < 0.001), ventilatory support (ventilator-free days to day 28: 16.0 [0.0–23.0] compared with 22.0 [8.0–25.0]; P < 0.001), and a higher 90-d mortality (29 compared with 23%; adjusted: RR = 1.17 [1.05, 1.30]; P = 0.003). CONCLUSION: Large GRVs were more common in males and those receiving energy-dense formulae, occurred early and were short-lived, and were associated with a number of negative clinical sequelae, including increased mortality, even when adjusted for illness severity. This trial was registered at clinicaltrials.gov as NCT02306746.