Gastric versus postpyloric enteral nutrition in elderly patients (age ≥ 75 years) on mechanical ventilation: a single-center randomized trial

Background: The risk of ventilator-associated pneumonia (VAP) is reduced when postpyloric enteral nutrition (EN) is administered compared to when gastric EN is administered in specific populations. In the present study, we tested the hypothesis that postpyloric EN is superior to gastric EN in reducing the incidence of VAP in elderly patients (age >= 75 years) who are admitted to the intensive care unit (ICU) and require mechanical ventilation. Methods: We performed a single-center randomized clinical trial involving elderly patients (age >= 75 years) who were admitted to the ICU and required mechanical ventilation. The patients were randomly assigned to either the postpyloric EN group or the gastric EN group. The primary outcome was the VAP rate. Results: Of the 836 patients screened, 141 patients were included in the study (70 in the postpyloric EN group and 71 in the gastric EN group). The patients in the postpyloric EN group were 82.0 (75.0-99.0) years old (male 61.4%), and those in the gastric EN group were 82.0 (75.0-92.0) years old (male 63.4%). The Acute Physiology and Chronic Health Evaluation II scores were 28.09 +/- 6.75 in the postpyloric EN group and 27.80 +/- 7.60 in the gastric EN group (P = 0.43). VAP was observed in 8 of 70 patients (11.4%) in the postpyloric EN group and in 18 of 71 patients (25. 4%) in the gastric EN group, which resulted in a significant between-group difference (OR 0.38, 95% CI 0.15-0.94; P = 0.04). In the postpyloric EN group, there were significant reductions in vomiting (12 patients in the postpyloric EN group vs 29 patients in the gastric EN group; OR 0.30, 95% CI 0.14-0.65; P = 0.002) and abdominal distension (18 patients in the postpyloric EN group vs 33 patients in the gastric EN group; OR 0.40, 95% CI 0.20-0.81; P = 0.01). No significant differences were observed between the two groups regarding mortality and other secondary outcomes. Conclusions: Our study demonstrated that, compared with gastric EN, postpyloric EN reduced the VAP rate among elderly patients who were admitted to the ICU and required mechanical ventilation.