Evolving pathogens in the surgical intensive care unit: a 6-year experience

Area of Science:

• Infectious Diseases
• Critical Care Medicine
• Microbiology

Background:

• Nosocomial infections are a significant cause of morbidity and mortality in intensive care units (ICUs).
• The rise of multidrug-resistant pathogens complicates the management of critically ill patients.
• This study focuses on microbial trends in a surgical ICU (SICU).

Purpose of the Study:

• To investigate and document changing microbial trends within the Los Angeles County/University of Southern California Medical Center SICU.
• To identify shifts in the prevalence of drug-resistant pathogens over a six-year period.

Main Methods:

• A six-year retrospective cohort study (2000-2005) of adult patients (18-85 years) with positive blood, urine, or sputum cultures.
• Data analysis included pathogen classification, culture dates, infection types, and patient demographics.
• Patients were divided into two groups: past (2000-2002) and present (2003-2005) for trend analysis.

Main Results:

• Gram-positive (GP) organisms became more prevalent in respiratory and urine cultures over the study period.
• Oxacillin-resistant Staphylococcus aureus (ORSA) significantly increased in blood and respiratory cultures.
• ORSA constituted a larger proportion of staphylococcal species in the present group.

Conclusions:

• Gram-positive organisms are playing an increasing role in infections among critically ill SICU patients.
• Staphylococcal species, particularly drug-resistant strains like ORSA, are becoming more common.
• Continuous surveillance of microbial trends, especially drug-resistant pathogens, is essential in SICUs.