Evaluating the Impact of Enteral Glutamine Supplementation on Preventing Ventilator-Associated Pneumonia: A Pilot Randomized Clinical Trial in Critically Ill Patients
Abstract
Background: Ventilator-associated pneumonia (VAP) is a common and serious complication of mechanical ventilation in intensive care units (ICUs). The current study evaluates the effectiveness of enteral glutamine (GLN) supplementation in preventing VAP in ICU patients.
Methods: This controlled, randomized clinical trial was performed on mechanically ventilated ICU patients who had a Clinical Pulmonary Infection Score (CPIS) of ≤ 6 within 48 hours of starting ventilation. Patients in the intervention group received 40 g of GLN during the first 48 hours after intubation, and this was continued for seven days. Both the intervention and control groups received standard preventive care. Outcomes were evaluated by comparing the incidence of VAP, the number of pneumonia-free days, and the duration of ventilation and ICU length of stay in each group.
Results: We analyzed the medical records of 613 patients to identify those who met the eligibility criteria for our study, resulting in a final cohort of 35 participants (16 in the intervention group and 19 in the control group). The present clinical trial did not reach its target sample size of 23 patients per group, primarily because of participant attrition and loss to follow-up. Our findings revealed no significant differences in the incidence of early, late, or overall VAP between the two groups. However, the number of pneumonia-free days was significantly higher in the intervention group compared to the control group (log-rank test: P-value= 0.05). Other secondary outcomes, such as mortality rate, and the duration of ICU stay, hospital stay, and mechanical ventilation, also showed no significant differences between the two groups.
Conclusion: The administration of oral GLN supplements has been associated with an increase in the number of pneumonia-free days among ICU patients; however, this benefit does not appear to reduce the incidence of VAP. Further high-quality studies are warranted to validate these observations and to investigate the potential efficacy of GLN supplementation within specific patient cohorts.
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| Issue | Vol 13, No 3 (Summer 2025) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/jpc.v13i3.20322 | |
| Keywords | ||
| Pneumonia Intensive Care Unit Ventilator-Associated Glutamine | ||
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