Inadequate therapy and antibiotic resistance. Risk factors for mortality in the intensive care unit.
BACKGROUND
The impact of nosocomial infections and multidrug resistance on mortality is a topic of considerable controversy.


METHODS
A prospective, nested case control study was conducted in four intensive care units (ICUs) in Mexico to measure the impact of antibiotic resistance on and identify the main risk factors for mortality in critically ill patients with nosocomial infections.


RESULTS
One hundred thirteen patients developed 119 nosocomial infections. Multivariate analysis identified two variables that were significantly and independently associated with mortality: ventilator-associated pneumonia (p = 0.0041, odds ratio [OR] = 7.7) and inadequate antibiotic treatment (p <0.0001, OR = 70.5). Although antibiotic resistance in Gram-negative rods was not an independent risk factor for mortality, there was a strong association between antibiotic resistance and inadequate treatment (chi2 for linear trend = 29.3, p <0.00001). For patients with ventilator-associated pneumonia, predicted mortality calculated by APACHE II score was 23% compared to an observed mortality of 71%.


CONCLUSIONS
In this study the major risk factors for mortality were inadequate antibiotic treatment and development of ventilator-associated pneumonia. Multidrug resistance significantly increased the probability of receiving inadequate antibiotic treatment. The striking differences between observed and predicted mortality in these four ICUs indicate the need for further research and a reassessment of the current programs for prevention and control of nosocomial infections in Mexico.
Zaidi
Mussaret
M
Departamento de Investigación y Cuidados Intensivos, Hospital General O'Horan, Mérida, Yucatán, Mexico. mbzaidi@yuc.quik.com
Sifuentes-Osornio
José
J
Rolón
Ana Lilia
AL
Vázquez
Gabriela
G
Rosado
Rilke
R
Sánchez
Mauro
M
Calva
Juan J
JJ
de León-Rosales
Samuel Ponce
SP
D016022:Case-Control Studies; D004352:Drug Resistance, Microbial; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D011446:Prospective Studies; D012307:Risk Factors