Assessment of the prevalence of microaspiration by gastric pepsin in the airway of ventilated children

Aim: Mechanically ventilated patients are at risk for aspiration of gastric contents. The aim of this observational study was to determine the prevalence of micro-aspiration in children with cuffed and uncuffed endotracheal (ET) tubes and with tracheostomies and to assess the effect of feeding status on aspiration. Micro-aspiration was determined by measuring gastric pepsin in tracheal aspirates. Methods: We studied 27 children on ventilators in paediatric intensive care unit (PICU) and 10 children undergoing elective surgeries for various indications. Tracheal aspirates were collected from children on ventilatory support in the intensive care unit during medically indicated suctioning and from the group of children undergoing elective surgery in the operation room. Pepsin was detected by enzymatic assay. Results: Overall 70% of cases in PICU were positive for pepsin in at least one of the aspirates. Pepsin positivity was significantly lower in the cuffed group than in the uncuffed and tracheostomy groups. Tube feedings did not significantly influence the prevalence of pepsin positivity. Conclusions: Measurement of gastric pepsin in tracheobronchial fluid is a sensitive tool to detect aspirations in mechanically ventilated children and to assess the efficacy of preventive measures in PICU settings.