Risk factors for developing pneumonia within 48 hours of intubation

Am J Respir Crit Care Med. 1999 Jun;159(6):1742-6. doi: 10.1164/ajrccm.159.6.9808030.


Two hundred fifty intubated patients were followed during the first 48 h after intubation in order to identify potential risk factors for developing pneumonia within this period. Thirty-two developed pneumonia during this time. Univariate analysis established that large volume aspiration, presence of sedation, intubation caused by respiratory/cardiac arrest or decrease in the level of consciousness, emergency procedure, cardiopulmonary resuscitation (CPR), and Glasgow coma score < 9 were significantly associated with pneumonia. In contrast, prior infection and prior antimicrobial use were associated with a protective effect. Presence of subglottic secretion drainage and 15 other variables had no significant effect. Multivariate analysis selected CPR (odds ratio [OR] = 5.13, 95% confidence intervals [CI] = 2.14, 12.26) and continuous sedation (OR = 4.40, 95% CI = 1.83, 10.59) as significant risk factors for pneumonia, while antibiotic use (OR = 0.29, 95% CI = 0.12, 0.69) showed a protective effect. Our findings emphasize that risk factors for pneumonia change during the intubation period, and preventing pneumonia requires a combined approach.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Infections
  • Cardiopulmonary Resuscitation / adverse effects
  • Cohort Studies
  • Consciousness / physiology
  • Emergency Medical Services
  • Female
  • Glasgow Coma Scale
  • Humans
  • Hypnotics and Sedatives / adverse effects
  • Incidence
  • Intubation / adverse effects*
  • Male
  • Middle Aged
  • Pneumonia / chemically induced
  • Pneumonia / epidemiology
  • Pneumonia / etiology*
  • Pneumonia / microbiology
  • Prospective Studies
  • Risk Factors
  • Time Factors


  • Hypnotics and Sedatives