The Association between Positive Tracheal Aspirate Cultures and Adverse Pulmonary Outcomes in Preterm Infants with Severe Bronchopulmonary Dysplasia

Am J Perinatol. 2017 Jan;34(1):96-104. doi: 10.1055/s-0036-1584541. Epub 2016 Jun 10.

Abstract

Objective Bacterial colonization of the airway may contribute to the development of bronchopulmonary dysplasia. Whether airway colonization increases risk for later adverse respiratory outcomes is less clear. We described tracheal aspirate culture results obtained from preterm infants receiving mechanical ventilation at 36 weeks postmenstrual age (PMA) and evaluated the association between bacteria type and the risk for prolonged supplemental oxygen use. Study Design We conducted a retrospective, single-center cohort study comparing infants (1) with and without a tracheal aspirate culture that grew a Gram-negative rod (GNR) and (2) with and without a culture that grew a Gram-positive cocci (GPC). Results Among 121 infants, 65 (53.7%) and 51 (42.2%) had a tracheal aspirate culture that grew a potentially pathogenic GNR and GPC prior to 36 weeks PMA, respectively. GNR were associated with increased risk for death or use of supplemental oxygen at discharge (adjusted odds ratio [aOR], 6.2; 95% confidence interval [CI], 1.8-21.1), and use of supplemental oxygen at discharge among survivors (aOR, 5.5; 95% CI, 1.6-19.0). GPC did not affect the risk for any study outcomes. Conclusion GNR but not GPC in the airways of preterm infants receiving mechanical ventilation at 36 weeks PMA is associated with increased risk for prolonged supplemental oxygen use.

MeSH terms

  • Bronchopulmonary Dysplasia / epidemiology*
  • Cohort Studies
  • Female
  • Gestational Age
  • Gram-Negative Bacteria / isolation & purification
  • Gram-Negative Bacterial Infections / epidemiology*
  • Gram-Negative Bacterial Infections / microbiology
  • Gram-Positive Bacterial Infections / epidemiology*
  • Gram-Positive Bacterial Infections / microbiology
  • Gram-Positive Cocci / isolation & purification
  • Humans
  • Infant
  • Infant, Extremely Premature
  • Infant, Newborn
  • Infant, Premature
  • Infant, Very Low Birth Weight
  • Male
  • Odds Ratio
  • Oxygen Inhalation Therapy
  • Patient Discharge
  • Perinatal Death
  • Respiration, Artificial*
  • Respiratory Distress Syndrome, Newborn / therapy*
  • Retrospective Studies
  • Severity of Illness Index
  • Trachea / microbiology

Supplementary concepts

  • Respiratory Distress Syndrome In Premature Infants