Epidemiology, risk factors and outcome of nosocomial infections in a Respiratory Intensive Care Unit in North India

Abstract

Objective: To determine the epidemiology, risk factors and outcome of infections in a Respiratory Intensive Care Unit (RICU) of a tertiary care institute in northern India.

Methodology: Prospective, observational clinical study.

Results: The study included 201 patients (1285 patient days) admitted to RICU over a period of one-and-a-half years. A total of 77 infections were identified in 67 patients (33.5%). The infections included pneumonia (23%), sepsis of unknown origin (10.5%), bacteremia (7.5%), urinary tract infections (1.5%), catheter related blood stream infections (1%) and Clostridium difficile colitis (1%). The most commonly identified organisms were the Acinetobacter species (34.8%), Pseudomonas aeruginosa (23.9%) and Escherichia coli (15.2%). The median length of stay in patients with and without infection was 13 days (interquartile range, IQR, 28) and 4 days (interquartile range, IQR, 3), respectively (p<0.0001). Multivariate analysis showed the following risk factors for ICU-acquired infection: the admitting diagnosis of infection (odds ratio [OR] 3.3; 95% confidence intervals [CI] 1.06-10.1), length of stay in the RICU (OR, 1.2; 95% confidence intervals [CI] 1.1-1.33); renal failure (OR, 4.7; 95% CI, 1.52-14.41) and institution of parenteral nutrition (OR, 16.9; 95% CI, 1.07-269.03). Multivariate analysis showed the following risk factors for death in ICU: APACHE II scores (OR, 1.06; 95% CI, 1.01-1.11), and endotracheal intubation (OR, 5.07; 95% CI, 1.24-20.65).

Conclusions: This study clearly documents a high prevalence rate of infections in the ICU, and the data suggest that occurrence of infections was associated with a prolonged ICU stay but had no significant effect on the final outcome.