Use of methylene blue spectrophotometry to detect subclinical aspiration in enterally fed intubated pediatric patients

Objective: Enteral feeding is widely used in ventilated patients admitted to pediatric intensive care units. Although studies in adult patients have shown that the site of feeding (stomach vs. small intestine) may be associated with aspiration pneumonia, there are no such reports in critically ill pediatric patients. We hypothesized that in intubated pediatric patients, there was no difference in the frequency of aspiration between nasogastric and postpyloric enteral feeding. Design: Randomized, prospective clinical study. Setting: Single pediatric intensive care unit of a tertiary care children’s hospital. Patients: Forty-four intubated patients (≤18 yrs old). Interventions: Intubated patients were randomized to receive either nasogastric (n = 27) or postpyloric (n = 17) enteral feeding. Feeding tube placement by the bedside nurse was confirmed by abdominal radiograph. Methylene blue was added at a standard dilution to an age-appropriate formula. Tracheal secretions were suctioned every 8 hrs, tested for blue color by observation, and analyzed via spectrophotometry. Patients were followed until feeds were stopped for anticipated extubation. Aspiration pneumonia was defined using criteria of the Centers of Disease Control and Prevention (CDC). Measurements and Main Results: Methylene blue was detected in two patients in the postpyloric group by spectrophotometry. None of the patients met the CDC criteria for aspiration. There was no difference in the frequency of aspiration between the two groups (p < .07). The time until beginning feedings in the postpyloric group was greater than that for the nasogastric group (18–24 hrs vs. 6 hrs, p < .05). The postpyloric group required more abdominal radiographs compared with the nasogastric group (three radiographs vs. one, p < .05). Conclusions: Use of nasogastric feeding shortens the time needed to reach nutritional goals and reduces the number of radiographic studies. Nasogastric feeding demonstrates no increase in aspiration compared with postpyloric feeding in intubated pediatric patients.