Abstract:
Nosocomial lower respiratory tract infection (LRI) is a common problem in
Thailand , especially among patients who receive mechanical ventilation (MV). The
purpose of this case-control study was to determine factors associated with
nosocomial lower respiratory tract infection in ventilated patients. The population of
this study consisted of patients over 15 years old who were admitted to Saraburi
Hospital during 1st April 2002 to 31st March 2003, and who had received mechanical
ventilation (MV) for more than 48 hours. Cases were ventilated patients who had
developed LRI, while controls were ventilated patients who had not developed LRI
following the diagnosis of nosocomial LRI, including pneumonia, reported by
physicians. There were 145 cases and 295 controls.
In multiple logistic regression analysis, it was found that these factors, principal
disease (trauma), surgery (tracheostomy and other types of surgery) and prior
antibiotic use, explained 40.5 percent of variance among nosocomial LRI in ventilated
patients in Saraburi Hospital R2 =40.5% ). The test indicated that after controlling for
the effect of other variables, the ventilated patients with trauma had 4.31 times the
risk of developing nosocomial LRI on MV as compared to those with other diseases
Tracheostomy and other surgery patients had higher risks for developing nosocomial
LRI on MV than those who had not received any surgery (16.96 and 2.59 times,
respectively). The last factor, prior antibiotic use, was a protective factor against
developing nosocomial LRI on MV (odds ratio = 0.28).