Hospital infection in a school of medicine intensive care unit: patient evaluation according to ward of origin

Hospital infection in a school of medicine intensive care unit. Patient evaluation according to ward of origin.

THESIS: S. R. L. R. Olbrich submitted this dissertation for her Masters in Tropical Diseases at Botucatu School of Medicine, São Paulo State University, UNESP, Botucatu, São Paulo, Brazil, 2000.

Advisor: Professor Rinaldo Poncio Mendes

^{Address to correspondence}

ABSTRACT: Conditions predisposing to the development of nosocomial infection (NI) are concentrated in the Intensive Care Unit (ICU), where a large number of invasive procedures and antimicrobial agents are used. This study evaluated the clinical and epidemiological aspects related to NI in patients admitted to the Central ICU and from wards in the University Hospital, Botucatu Medical School, São Paulo State University from May 1^st to October 31^st 1997. The ICU has four beds allocated for patients aged at least 12 years old who had been submitted to clinical and/or surgical treatment. All 93 patients admitted during this period were evaluated; the criteria used for NI diagnosis were proposed by the Centers For Disease Control and Prevention (1988). Most patients (76.3%) were 40 years old or more, with a median of 57 years.

On admission to the ICU, 22.6% presented community infection (CI), 20.4% NI, and 6.5% community nosocomial infection (CNI). Hospitalization in the ward of origin ranged from 1 to 43 days, with a mean of 6.3 days. Infections occurred at higher frequency in the respiratory tract (48.6%), followed by gastrointestinal tract (15.3%), urinary tract (11.1%), and blood stream (11.1%). A risk procedure was performed on 89.3% of patients; 75.2% were taking an antibacterial agent, and most were infected or colonized by multiresistant microorganisms.

Events in the ICU - Average stay was longer for NI group (14.3 days) than non-infection group (2.9 days). The most frequent diagnoses leading to transfer to the ICU were diseases of the respiratory tract (31.8%) and circulatory apparatus (24.7%). Patients with NI was 47.3%; the risk of patients admitted with an infection acquiring a new infection was 2.5-fold higher than those admitted without infection. The infected sites were the respiratory tract (39.2%), blood stream (16.5%), and urinary tract (15.2%). Infection rate due to risk procedures was higher in patients receiving assisted respiration (40.7%), followed by surgical procedures (16.9%), delayed bladder catheterization (16.2%), and central venous catheterization (11.1%). The most frequent microorganisms were Pseudomonas aeruginosa (35.9%), Klebsiella pneumoniae (13.9%), coagulase-negative Staphylococcus (8.0%), and yeasts (7.5%). There was a high resistance to most tested drugs; no antibacterial agent was effective against all Pseudomonas aeruginosa strains and two strains were resistant to all drugs. Cefepime showed the highest sensitivity (81.4%). All Gram-positive strains were sensitive to vancomycin. These results show that is important to know the patients’ conditions on admission to the ICU and that previous infectious diseases increase the risk of NI in the Intensive Care Unit.

Key words: nosocomial infection, Intensive Care Unit, University Hospital.

Publication Dates

• Publication in this collection
  09 Dec 2003
• Date of issue
  2003