Gastric vs small-bowel feeding in critically ill children receiving mechanical ventilation: a randomized controlled trial.

STUDY OBJECTIVES: To determine the effect of feeding tube position (gastric vs small bowel) on adequacy of nutrient delivery and feeding complications, including microaspiration, in critically ill children. DESIGN: Randomized controlled trial. SETTING: Pediatric ICU in a university teaching hospital. PATIENTS: Seventy-four critically ill patients < 18 years of age receiving mechanical ventilation were randomized to receive gastric or small-bowel feeding. INTERVENTIONS: All feeding tubes were inserted at the bedside. Color, pH, and bilirubin concentration of the feeding tube aspirates were used to guide placement. Final tube position was confirmed radiographically. Continuous feedings were advanced to achieve a caloric goal based on age and body weight. Tracheal secretions were collected daily and tested for gastric pepsin by immunoassay. MEASUREMENTS AND RESULTS: Thirty-two patients were randomized to the gastric group, and 42 patients were randomized to the small-bowel group. Twelve patients exited the study because a small-bowel tube could not be placed at the bedside, leaving 30 patients in the small-bowel group. Gastric and small-bowel groups were similar at baseline in age, sex, percentage of ideal body weight, serum prealbumin concentration, and pediatric risk of mortality score. The percentage of daily caloric goal achieved was less in the gastric group compared to the small-bowel group (30 +/- 23% vs 47 +/- 22%, p < 0.01). No difference was found in the proportion of tracheal aspirates positive for pepsin between the gastric and small-bowel groups (50 of 146 aspirates vs 50 of 172 aspirates, respectively; p = 0.3). No differences were found in the frequency of feeding tube displacement, abdominal distension, vomiting, or diarrhea between groups. CONCLUSIONS: Small-bowel feeds allow a greater amount of nutrition to be successfully delivered to critically ill children. Small-bowel feeds do not prevent aspiration of gastric contents.

Pressure-controlled ventilation in children with severe status asthmaticus.

OBJECTIVE: The optimum strategy for mechanical ventilation in a child with status asthmaticus is not established. Volume-controlled ventilation continues to be the traditional approach in such children. Pressure-controlled ventilation may be theoretically more advantageous in allowing for more uniform ventilation. We describe our experience with pressure-controlled ventilation in children with severe respiratory failure from status asthmaticus. DESIGN: Retrospective review. SETTING: Pediatric intensive care unit in a university-affiliated children's hospital. PATIENTS: All patients who received mechanical ventilation for status asthmaticus. INTERVENTIONS: Pressure-controlled ventilation was used as the initial ventilatory strategy. The optimum pressure control, rate, and inspiratory and expiratory time were determined based on blood gas values, flow waveform, and exhaled tidal volume. MEASUREMENT AND MAIN RESULTS: Forty patients were admitted for 51 episodes of severe status asthmaticus requiring mechanical ventilation. Before the institution of pressure-controlled ventilation, median pH and Pco(2) were 7.21 (range, 6.65-7.39) and 65 torr (29-264 torr), respectively. Four hours after pressure-controlled ventilation, median pH increased to 7.31 (6.98-7.45, p <.005), and Pco(2) decreased to 41 torr (21-118 torr, p <.005). For patients with respiratory acidosis (Pco(2) >45 torr) within 1 hr of starting pressure-controlled ventilation, the median length of time until Pco(2) decreased to <45 torr was 5 hrs (1-51 hrs). Oxygen saturation was maintained >95% in all patients. Two patients had pneumomediastinum before pressure-controlled ventilation. One patient each developed pneumothorax and subcutaneous emphysema after initiation of pressure-controlled ventilation. All patients survived without any neurologic morbidity. Median duration of mechanical ventilation was 29 hrs (4-107 hrs), intensive care stay was 56 hrs (17-183 hrs), and hospitalization was 5 days (2-20 days). CONCLUSIONS: Based on this retrospective study, we suggest that pressure-controlled ventilation is an effective ventilatory strategy in severe status asthmaticus in children. Pressure-controlled ventilation represents a therapeutic option in the management of such children.

Detection of pepsin and glucose in tracheal secretions as indicators of aspiration in mechanically ventilated children.

OBJECTIVES: The detection of glucose in tracheal secretions has been used as an indicator of aspiration in mechanically ventilated, tube-fed children. Pepsin detection may be a more specific indicator. We determined the frequency of pepsin and glucose detection in tracheal secretions of mechanically ventilated children and studied the relationships between tracheal secretion pepsin and glucose and clinical evidence of gastroesophageal reflux. DESIGN: Prospective observational study. SETTING: University teaching hospital. PATIENTS: A convenience sample of mechanically ventilated children. INTERVENTIONS: Tracheal secretions were collected at the time of routine endotracheal tube suctioning. Tracheal aspirate glucose concentrations were assessed by using glucose oxidase reagent strips. Tracheal aspirate pepsin was detected by laboratory immunoassay. MEASUREMENTS AND MAIN RESULTS: One hundred tracheal aspirates were collected from 37 children. Pepsin (>or=1 microg/mL) was detected in nine aspirates, and glucose (>or=20 mg/dL) was detected in 59 aspirates. Overall, five (13.5%) patients had at least one pepsin-positive aspirate, and 33 (89%) had at least one glucose-positive aspirate. Patients with at least one pepsin-positive aspirate were more likely to have clinical evidence of gastroesophageal reflux than patients with pepsin-negative aspirates (5 of 5 vs. 9 of 32, p <.01, Fisher's exact test). Tracheal aspirate glucose positivity was unrelated to the administration of tube feedings and gastroesophageal reflux. No relationship between pepsin and glucose positivity was observed. CONCLUSIONS: Pepsin is detectable in tracheal secretions of mechanically ventilated children at risk for aspiration. Elevated glucose concentrations in tracheal secretions can occur by mechanisms other than aspiration of glucose-rich formula. Pepsin may be a more specific marker for aspiration than glucose.