Nosocomial infections in the Intensive care unit: global problem of modern medicine

Abstract

Increased volume of surgical interventions, improvement of efficiency of special treatment modalities and modes of respiratory support, as well as development of new generation antibiotic medications has led to significant improvement of clinical outcomes of intensive therapy for critical conditions. At the same time, introduction of innovative and largely invasive interventions resulted in the emergence of new disease entities.
 Presently, the development of hospital-acquired infections (HAI) has become one of the riveting and serious problems of modern hospitals. These infections often lead to prolonged hospital stay, which in turn adds to the morbidity and mortality, worsen patient quality of life and also has significant economic consequences [1-5].
 There are number of varying definitions of infections related to medical care [6]. According to the WHO, infections that develop 48 hours after hospitalization, excluding the incubation period, are called hospital-acquired or nosocomial infections. Some authors also include here infections that develop 4 weeks after patient’s discharge from hospital or 30 days after surgical interventions are also included in this category. Infections that develop within 30 days after last chemotherapy in patients with metastatic cancer are also included as additional criteria according to a medical literature [7]. Other authors conclude that readmission of patients with established infection that was the result of previous hospitalization as well as any infectious diseases of hospital employee that develops secondary to the work in the hospital, irrespective to the time of onset of symptoms (during or after the hospital visit or stay) shall also be regarded as the hospital-acquired infections (HAI) [8-10].
 The average prevalence of HAI is around 3.5-10.5% or 9.0-91.7 cases per 1000 patient-days [11]. It is estimated that the probability of infectious complications increases after five days of hospitalization [12]. According to the modern medical knowledge, the prevalence of HAI of various causes among the hospitalized patients in North America and Europe is around 5-10% and those in Latin America and Asia is around 40% [13,14]. The mortality among patients with HAI is seven times higher than among other patients aligned based on age, sex, main disease and comorbidities and severity of disease. According to the official statistics, HAIs are fourth most common cause of mortality in the US leading to 90.000 deaths annually. Annual economic burden and additional costs associated with the treatment of HAIs in the US is about 2.4-4.5 billion US dollars [15-17].