Severe traumatic brain injury (TBI) is a catastrophic event that often has destructive familial, economic, and societal consequences. It contributes to many deaths and cases of permanent disability, especially among patients 15-30 years old. 8,10 The average mortality rate for patients with severe TBI is 39%, and 60% of these patients have an unfavorable outcome on the Glasgow Outcome Scale. 24,26 Furthermore, those who survive tend to have significant disabilities, which also can cause a major socioeconomic burden.Patients with severe TBI have reduced immune function and higher risks of nosocomial infections as a result of decreased energy and increased protein catabolism. 4,7 By providing additional daily calories, nutrition support abbreviatioNs APACHE II = Acute Physiology and Chronic Health Evaluation II; GCS = Glasgow Coma Scale; ICU = intensive care unit; ISS = Injury Severity Score; MV = mechanical ventilation; RCT = randomized controlled trial; RR = risk ratio; TBI = traumatic brain injury; VAP = ventilator-associated pneumonia; WMD = weighted mean difference. obJect Nutritional support is highly recommended for reducing the risk of nosocomial infections, such as pneumonitis, in patients with severe traumatic brain injury (TBI). Currently, there is no consensus for the preferred route of feeding. The authors compared the risks of pneumonitis and other important outcomes associated with small intestinal and gastric feeding in patients with severe TBI. methods This systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant randomized controlled trials (up to December 16, 2013) that compared small bowel to gastric feeding in patients with severe TBI were identified from searches in the PubMed and Embase databases. The primary outcome was risk of pneumonia. Secondary outcomes included ventilatorassociated pneumonia, mortality, length of intensive care unit stay, length of hospital stay, duration of mechanical ventilation, total number of complications, aspiration, diarrhea, distention, Glasgow Coma Scale score, Injury Severity Score, and Acute Physiology and Chronic Health Evaluation II score. results Five randomized controlled trials with 325 participants in total were included in the meta-analysis. Compared with gastric feeding, small bowel feeding was associated with a significant reduction in the incidence of pneumonitis (risk ratio [RR] 0.67; 95% CI 0.52-0.87; p = 0.002; I 2 = 0.0%) and ventilator-associated pneumonia (RR 0.52; 95% CI 0.34-0.81; p = 0.003; I 2 = 0.0%). Small intestinal feeding was also associated with a decrease in the total number of complications (RR 0.43; 95% CI 0.20-0.93; p = 0.03; I 2 = 68%). However, small intestinal feeding did not seem to significantly convert any of the other end points in the meta-analysis. coNclusioNs The limited evidence suggests that small bowel feeding in patients with severe TBI is associated with a risk of pneumonia that is lower than that with gast...