Surfactant content in children with inflammatory lung disease

Crit Care Med. 1996 Jun;24(6):1062-7. doi: 10.1097/00003246-199606000-00029.


Objective: To determine surfactant profiles of tracheal secretions in mechanically ventilated children with respiratory failure secondary to bacterial pneumonia, viral pneumonitis, adult respiratory distress syndrome (ARDS), and cardiopulmonary bypass.

Design: Prospective, cohort study.

Setting: Tertiary, multidisciplinary, pediatric intensive care unit.

Patients: One hundred twenty pediatric patients with respiratory failure requiring mechanical ventilation.

Interventions: Routine tracheal aspirates were collected from children with bacterial pneumonia, viral pneumonitis, ARDS, postcardiopulmonary bypass, and a postsurgical control group. Samples were obtained on days 1, 2, 3, after every week of intubation and on the day of extubation.

Measurements and main results: The tracheal aspirates were analyzed by high-performance liquid chromatography for lecithin/sphingomyelin rations and by enzyme-linked immunosorbent assay for surfactant proteins A and B. Lung compliance and the oxygenation index were measured on each day of sample collection. On day 1, patients with bacterial pneumonia, viral pneumonitis, and ARDS had decreased lecithin/sphingomyelin ration (p < .001), and those patients with bacterial pneumonia and viral pneumonitis had decreased surfactant protein A/protein concentration (p < .001). The lecithin/sphingomyelin ratios and surfactant protein A/protein concentration were significantly different among the groups (p < .001), with the bacterial pneumonia and viral pneumonitis groups having higher lecithin/sphingomyelin ratios and increased surfactant protein concentrations before extubation. Pulmonary compliance was lower and the oxygenation index was higher than controls (p < .001) in patients with bacterial pneumonia, viral pneumonitis, and ARDS. Pulmonary compliance was correlated weakly with lecithin/sphingomyelin ratio (r2 = .11, p < .001) and surfactant protein A/protein concentration (r2 = .03, p < .05). Surfactant protein B was similar in the diagnostic groups. Surfactant content in tracheal secretions from cardiopulmonary bypass patients was equivalent to controls.

Conclusion: Abnormal tracheal aspirate surfactant phospholipids and surfactant protein A were noted in children with bacterial pneumonia, viral pneumonitis, and ARDS, but not in children on cardiopulmonary bypass.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cardiopulmonary Bypass
  • Child
  • Child, Preschool
  • Cohort Studies
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Intensive Care Units, Pediatric
  • Lung Compliance
  • Male
  • Pneumonia, Bacterial / complications
  • Pneumonia, Viral / complications
  • Prospective Studies
  • Pulmonary Surfactants / analysis*
  • Respiration, Artificial
  • Respiratory Distress Syndrome / complications
  • Respiratory Insufficiency / etiology
  • Respiratory Insufficiency / pathology*
  • Respiratory Insufficiency / therapy
  • Trachea / chemistry*


  • Pulmonary Surfactants