Stijn Blot

Clinical and Economic Outcomes in Critically Ill Patients with Nosocomial Catheter-Related Bloodstream Infections

BACKGROUND Central venous catheters are universally used during the treatment of critically ill patients. Their use, however, is associated with a substantial infection risk, potentially leading to increased mortality and costs. We evaluate clinical and economic outcomes associated with nosocomial central venous catheter-related bloodstream infection (CR-BSI) in intensive care unit (ICU) patients. METHODS A retrospective (1992-2002), pairwise-matched (ratio of case patients to control subjects, 1:2 or 1:1), risk-adjusted cohort study was performed at a 54-bed general ICU at a university hospital. ICU patients with microbiologically documented CR-BSI (n = 176) were matched with control subjects (n = 315) on the basis of disease severity, diagnostic category, and length of ICU stay (equivalent or longer) before the onset of CR-BSI in the index case patient. Clinical outcome was principally evaluated by in-hospital mortality. Economic outcome was evaluated on the basis of duration of mechanical ventilation, length of ICU and hospital stays, and total hospital costs, as derived from the patients hospital invoices. RESULTS The attributable mortality rate for CR-BSI was estimated to be 1.8% (95% confidence interval, -6.4% to 10.0%); in-hospital mortality rates for patients with CR-BSI and matched control subjects were 27.8% and 26.0%, respectively. CR-BSI was associated with significant excesses in duration of mechanical ventilation, duration of ICU and hospital stays, and a significant increase in total hospital cost. Linear regression analysis with adjustment for duration of hospitalization and clinical covariates, revealed that CR-BSI is independently associated with higher costs. CONCLUSIONS In ICU patients, CR-BSI does not result in increased mortality. It is, however, associated with a significant economic burden, emphasizing the importance of continuous efforts in prevention.

Effects of nosocomial candidemia on outcomes of critically ill patients

PURPOSE To determine whether nosocomial candidemia is associated with increased mortality in intensive care unit (ICU) patients. SUBJECTS AND METHODS We performed a retrospective (1992 to 2000) cohort study of 73 ICU patients with candidemia and 146 matched controls. Controls were matched based on disease severity as measured by the Acute Physiology and Chronic Health Evaluation (APACHE) II score (+/- 1 point), diagnostic category, and length of ICU stay before onset of candidemia. RESULTS In comparison with the control group, patients with candidemia developed more acute respiratory failure (97% [n = 71] vs. 88% [n = 129], P = 0.03) during their ICU stay. They were mechanically ventilated for a longer period (29 +/- 26 days vs. 19 +/- 19 days, P<0.01) and had a longer stay in the ICU (36 +/- 33 days vs. 25 +/- 23 days, P = 0.02) as well as in the hospital (77 +/- 81 days vs. 64 +/- 69 days, P = 0.04). There was no difference in in-hospital mortality between the groups (48% [n = 35] vs. 43% [n = 62], P = 0.44), a difference of 5% (95% confidence interval [CI]: -8% to 19%). In a multivariate analysis, older age (hazard ratio [HR] = 1.13 per 10 years; 95% CI: 1.04 to 1.23; P = 0.004), acute renal failure (HR = 1.4; 95% CI: 1.1 to 2.0; P = 0.02), and unfavorable APACHE II scores (HR = 1.10 per 5 points; 95% CI: 1.00 to 1.20; P = 0.05) were independent predictors of mortality. Candidemia was not associated with mortality in a model that adjusted for these factors (HR = 0.9; 95% CI: 0.7 to 1.2; P = 0.53). CONCLUSION Nosocomial candidemia does not adversely affect the outcome in ICU patients in whom mortality is attributable to age, the severity of underlying disease, and acute illness.

Severe burn injury in europe: a systematic review of the incidence, etiology, morbidity, and mortality

IntroductionBurn injury is a serious pathology, potentially leading to severe morbidity and significant mortality, but it also has a considerable health-economic impact. The aim of this study was to describe the European hospitalized population with severe burn injury, including the incidence, etiology, risk factors, mortality, and causes of death.MethodsThe systematic literature search (1985 to 2009) involved PubMed, the Web of Science, and the search engine Google. The reference lists and the Science Citation Index were used for hand searching (snowballing). Only studies dealing with epidemiologic issues (for example, incidence and outcome) as their major topic, on hospitalized populations with severe burn injury (in secondary and tertiary care) in Europe were included. Language restrictions were set on English, French, and Dutch.ResultsThe search led to 76 eligible studies, including more than 186,500 patients in total. The annual incidence of severe burns was 0.2 to 2.9/10,000 inhabitants with a decreasing trend in time. Almost 50% of patients were younger than 16 years, and ~60% were male patients. Flames, scalds, and contact burns were the most prevalent causes in the total population, but in children, scalds clearly dominated. Mortality was usually between 1.4% and 18% and is decreasing in time. Major risk factors for death were older age and a higher total percentage of burned surface area, as well as chronic diseases. (Multi) organ failure and sepsis were the most frequently reported causes of death. The main causes of early death (<48 hours) were burn shock and inhalation injury.ConclusionsDespite the lack of a large-scale European registration of burn injury, more epidemiologic information is available about the hospitalized population with severe burn injury than is generally presumed. National and international registration systems nevertheless remain necessary to allow better targeting of prevention campaigns and further improvement of cost-effectiveness in total burn care.

Clinical relevance of Aspergillus isolation from respiratory tract samples in critically ill patients

IntroductionThe diagnosis of invasive pulmonary aspergillosis, according to the criteria as defined by the European Organisation for the Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG), is difficult to establish in critically ill patients. The aim of this study is to address the clinical significance of isolation of Aspergillus spp. from lower respiratory tract samples in critically ill patients on the basis of medical and radiological files using an adapted diagnostic algorithm to discriminate proven and probable invasive pulmonary aspergillosis from Aspergillus colonisation.MethodsUsing a historical cohort (January 1997 to December 2003), all critically ill patients with respiratory tract samples positive for Aspergillus were studied. In comparison to the EORTC/MSG criteria, a different appreciation was given to radiological features and microbiological data, including semiquantitative cultures and direct microscopic examination of broncho-alveolar lavage samples.ResultsOver a 7 year period, 172 patients were identified with a positive culture. Of these, 83 patients were classified as invasive aspergillosis. In 50 of these patients (60%), no high risk predisposing conditions (neutropenia, hematologic cancer and stem cell or bone marrow transplantation) were found. Typical radiological imaging (halo and air-crescent sign) occurred in only 5% of patients. In 26 patients, histological examination either by ante-mortem lung biopsy (n = 10) or necropsy (n = 16) was performed, allowing a rough estimation of the predictive value of the diagnostic algorithm. In all patients with histology, all cases of clinical probable pulmonary aspergillosis were confirmed (n = 17). Conversely, all cases classified as colonisation had negative histology (n = 9).ConclusionA respiratory tract sample positive for Aspergillus spp. in the critically ill should always prompt further diagnostic assessment, even in the absence of the typical hematological and immunological host risk factors. In a minority of patients, the value of the clinical diagnostic algorithm was confirmed by histological findings, supporting its predictive value. The proposed diagnostic algorithm needs prospective validation.

Nosocomial Bacteremia Caused by Antibiotic-Resistant Gram-Negative Bacteria in Critically Ill Patients: Clinical Outcome and Length of Hospitalization

Population characteristics and outcomes were retrospectively compared for critically ill patients with nosocomial bacteremia caused by antibiotic-susceptible (AB-S; n=208) or antibiotic-resistant (AB-R; n=120) gram-negative bacteria. No significant differences in severity of illness and comorbidity factors were seen between groups. Patients with bacteremia caused by AB-R strains had a longer hospitalization before the onset of the bacteremia. The in-hospital mortality for patients with bacteremia caused by AB-S strains was 41.8%; for patients infected with AB-R strains, it was 45.0% (P=.576). A multivariate survival analysis demonstrated that older age (P=.009), a high-risk source of bacteremia (abdominal and lower respiratory tract; P=.031), and a high acute physiology and chronic health evaluation II-related expected mortality (P=.032) were independently associated with in-hospital mortality (P<.05). Antibiotic resistance in nosocomial bacteremia caused by gram-negative bacteria does not adversely affect the outcome for critically ill patients.

Prevention of ventilator-associated pneumonia with oral antiseptics: a systematic review and meta-analysis

BACKGROUND We did a systematic review and random effects meta-analysis of randomised trials to assess the effect of oral care with chlorhexidine or povidone-iodine on the prevalence of ventilator-associated pneumonia versus oral care without these antiseptics in adults. METHODS Studies were identified through PubMed, CINAHL, Web of Science, CENTRAL, and complementary manual searches. Eligible studies were randomised trials of mechanically ventilated adult patients receiving oral care with chlorhexidine or povidone-iodine. Relative risks (RR) and 95% CIs were calculated with the Mantel-Haenszel model and heterogeneity was assessed with the I(2) test. FINDINGS 14 studies were included (2481 patients), 12 investigating the effect of chlorhexidine (2341 patients) and two of povidone-iodine (140 patients). Overall, antiseptic use resulted in a significant risk reduction of ventilator-associated pneumonia (RR 0.67; 95% CI 0.50-0.88; p=0.004). Chlorhexidine application was shown to be effective (RR 0.72; 95% CI 0.55-0.94; p=0.02), whereas the effect resulting from povidone-iodine remains unclear (RR 0.39; 95% CI 0.11-1.36; p=0.14). Heterogeneity was moderate (I(2)=29%; p=0.16) for the trials using chlorhexidine and high (I(2)=67%; p=0.08) for those assessing povidone-iodine use. Favourable effects were more pronounced in subgroup analyses for 2% chlorhexidine (RR 0.53, 95% CI 0.31-0.91), and in cardiosurgical studies (RR 0.41, 95% CI 0.17-0.98). INTERPRETATION This analysis showed a beneficial effect of oral antiseptic use in prevention of ventilator-associated pneumonia. Clinicians should take these findings into account when providing oral care to intubated patients. FUNDING None.

Nosocomial bacteremia involving Acinetobacter baumannii in critically ill patients: a matched cohort study

ObjectiveTo determine outcome and attributable mortality in critically ill patients with nosocomial bacteremia involving A. baumannii.DesignA retrospective matched cohort study in which all ICU patients with microbiologically documented A. baumannii bacteremia were defined as cases. Matching of the controls was based on equivalent APACHE II score (±2 points) and diagnostic category. Control patients were required to have an ICU stay equivalent to or longer than the case prior to onset of the bacteremia.SettingThe 54–bed ICU of the 1060-bed Ghent University Hospital.Patients45 ICU patients with A. baumannii bacteremia and 90 matched control subjects without clinical or microbiological evidence of blood stream infection.MeasurementsPopulation characteristics and in-hospital mortality rates of patients with A. baumannii bacteremia and their controls were compared. Attributable mortality is determined by subtracting the crude mortality rate of the controls from the crude mortality rate of the cases.ResultsPatients with A. baumannii bacteremia had significantly more hemodynamic instability, longer ICU stay, and longer length of ventilator dependence than controls. In-hospital mortality rates for cases and controls were, respectively, 42.2% and 34.4%; thus the attributable mortality was 7.8%.ConclusionIn critically ill patients A. baumannii bacteremia is not associated with a significantly increased mortality rate.

The rising problem of antimicrobial resistance in the intensive care unit

Mainly due to its extremely vulnerable population of critically ill patients, and the high use of (invasive) procedures, the intensive care unit (ICU) is the epicenter of infections. These infections are associated with an important rise in morbidity, mortality, and healthcare costs. The additional problem of multidrug-resistant pathogens boosts the adverse impact of infections in ICUs. Several factors influence the rapid spread of multidrug-resistant pathogens in the ICU, e.g., new mutations, selection of resistant strains, and suboptimal infection control. Among gram-positive organisms, the most important resistant microorganisms in the ICU are currently methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. In gram-negative bacteria, the resistance is mainly due to the rapid increase of extended-spectrum Beta-lactamases (ESBLs) in Klebsiella pneumonia, Escherichia coli, and Proteus species and high level third-generation cephalosporin Beta-lactamase resistance among Enterobacter spp. and Citrobacter spp., and multidrug resistance in Pseudomonas aeruginosa and Acinetobacter species. To conclude, additional efforts are needed in the future to slow down the emergence of antimicrobial resistance. Constant evaluation of current practice on basis of trends in MDR and antibiotic consumption patterns is essential to make progress in this problematic matter.

Fungal Infections in Patients with Severe Acute Pancreatitis and the Use of Prophylactic Therapy

Data from an 8-year period for 46 patients with severe acute pancreatitis and infected pancreatic necrosis were analyzed to determine the incidence of fungal infection, to identify risk factors for the development of fungal infection, and to assess the use of early fluconazole treatment. Intraabdominal fungal infection was found in 17 (37%) of 46 patients. Candida albicans was isolated most frequently (15 patients); Candida tropicalis and Candida krusei were found in 1 patient each. Characteristics of patients with fungal infection were not different from patients without fungal infection. The difference in mortality was not statistically significant between patients with fungal infection and patients without fungal infection. Early antifungal therapy (prophylactic or preemptive antifungal therapy) was administered to 18 patients, and only 3 of them developed fungal infection. In this cohort of critically ill patients, no risk factors for fungal infection could be demonstrated, and mortality among patients who received early antifungal therapy was not different. Early treatment with fluconazole seems to prevent fungal infection in these high-risk patients.

Intra-abdominal hypertension in patients with severe acute pancreatitis

IntroductionAbdominal compartment syndrome has been described in patients with severe acute pancreatitis, but its clinical impact remains unclear. We therefore studied patient factors associated with the development of intra-abdominal hypertension (IAH), the incidence of organ failure associated with IAH, and the effect on outcome in patients with severe acute pancreatitis (SAP).MethodsWe studied all patients admitted to the intensive care unit (ICU) because of SAP in a 4 year period. The incidence of IAH (defined as intra-abdominal pressure ≥ 15 mmHg) was recorded. The occurrence of organ dysfunction during ICU stay was recorded, as was the length of stay in the ICU and outcome.ResultsThe analysis included 44 patients, and IAP measurements were obtained from 27 patients. IAH was found in 21 patients (78%). The maximum IAP in these patients averaged 27 mmHg. APACHE II and Ranson scores on admission were higher in patients who developed IAH. The incidence of organ dysfunction was high in patients with IAH: respiratory failure 95%, cardiovascular failure 91%, and renal failure 86%. Mortality in the patients with IAH was not significantly higher compared to patients without IAH (38% versus 16%, p = 0.63), but patients with IAH stayed significantly longer in the ICU and in the hospital. Four patients underwent abdominal decompression because of abdominal compartment syndrome, three of whom died in the early postoperative course.ConclusionIAH is a frequent finding in patients admitted to the ICU because of SAP, and is associated with a high occurrence rate of organ dysfunction. Mortality is high in patients with IAH, and because the direct causal relationship between IAH and organ dysfunction is not proven in patients with SAP, surgical decompression should not routinely be performed.