***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective To determine the attributable cost of ventilator-associated pneumonia from a hospital-based cost perspective , after adjusting for potential confounders . Design Patients admitted between January 19 , 1998 , and December 31 , 1999 , were followed prospect ively for the occurrence of ventilator-associated pneumonia . Hospital costs were defined by using the hospital cost accounting data base . Setting The medical and surgical intensive care units at a suburban , tertiary care hospital . Patients Patients requiring > 24 hrs of mechanical ventilation . Interventions None . Measurements and Main Results We measured occurrence of ventilator-associated pneumonia , in-hospital mortality rate , total intensive care unit ( ICU ) and hospital lengths of stay ( LOS ) , and total hospital cost per patient . Ventilator-associated pneumonia occurred in 127 of 819 patients ( 15.5 % ) . Compared with uninfected , ventilated patients , patients with ventilator-associated pneumonia had a higher Acute Physiology and Chronic Health Evaluation II score on admission ( p < .001 ) and were more likely to require multiple intubations ( p < .001 ) , hemodialysis ( p < .001 ) , tracheostomy ( p < .001 ) , central venous catheters ( p < .001 ) , and corticosteroids ( p < .001 ) . Patients with ventilator-associated pneumonia were more likely to be bacteremic during their ICU stay ( 36 [ 28 % ] vs. 22 [3%];p < .001 ) . Patients with ventilator-associated pneumonia had significantly higher unadjusted ICU LOS ( 26 vs. 4 days;p < .001 ) , hospital LOS ( 38 vs. 13 days;p < .001 ) , mortality rate ( 64 [ 50 % ] vs. 237 [34%];p < .001 ) , and hospital costs ( $ 70,568 vs. $ 21,620 , p < .001 ) . Multiple linear regression , controlling for other factors that may affect costs , estimated the attributable cost of ventilator-associated pneumonia to be $ 11,897 ( 95 % confidence interval = $ 5,265–$26,214;p < .001 ) . Conclusions Patients with ventilator-associated pneumonia had significantly longer ICU and hospital LOS , with higher crude hospital cost and mortality rate compared with uninfected patients . After we adjusted for underlying severity of illness , the attributable cost of ventilator-associated pneumonia was approximately $ 11,897 OBJECTIVES To characterize the current economic burden of ventilator-associated pneumonia ( VAP ) and to determine which services increase the cost of VAP in North American hospitals . DESIGN AND SETTING We performed a retrospective , matched cohort analysis of mechanically ventilated patients enrolled in the North American Silver-Coated Endotracheal Tube ( NASCENT ) study , a prospect i ve , r and omized study conducted from 2002 to 2006 in 54 medical centers , including 45 teaching institutions ( 83.3 % ) . METHODS Case patients with microbiologically confirmed VAP ( n = 30)were identified from 542 study participants with cl aims data and were matched by use of a primary diagnostic code , and subsequently by the Acute Physiology and Chronic Health Evaluation II score , to control patients without VAP ( n = 90 ) . Costs were estimated by applying hospital-specific cost-to-charge ratios based on all-payer inpatient costs associated with VAP diagnosis-related groups . RESULTS Median total charges per patient were $ 198,200 for case patients and $ 96,540 for matched control patients ( P < .001 ) ; corresponding median hospital costs were $ 76,730 for case patients and $ 41,250 for control patients ( P = .001 ) . After adjusting for diagnosis-related group payments , median losses to hospitals were $ 32,140 for case patients and $ 19,360 for control patients ( P = .151 ) . The median duration of intubation was longer for case patients than for control patients ( 10.1 days vs 4.7 days ; P < .001 ) , as were the median duration of intensive care unit stay ( 18.5 days vs 8.0 days ; P < .001 ) and the median duration of hospitalization ( 26.5 days vs 14.0 days ; P < .001 ) . Examples of services likely to be directly related to VAP and having higher median costs for case patients were hospital care ( P < .05 ) and respiratory therapy ( P < .05 ) . CONCLUSIONS VAP was associated with increased hospital costs , longer duration of hospital stay , and a higher number of hospital services being affected , which underscores the need for bundled measures to prevent VAP . TRIAL REGISTRATION NASCENT study Clinical Trials.gov Identifier : NCT00148642 HYPOTHESIS Catheter-related bloodstream infection ( CRBSI ) in critically ill surgical patients with prolonged intensive care unit ( ICU ) stays is associated with a significant increase in health care re source use . DESIGN Prospect i ve cohort study . SETTING Surgical ICU at a large tertiary care center . PATIENTS Critically ill surgical patients ( N = 260 ) with projected surgical ICU length of stay greater than 3 days . INTERVENTIONS Central venous catheters were cultured for clinical suspicion of infection . MAIN OUTCOME MEASURES Increases in total hospital cost , ICU cost , hospital days , and ICU days attributable to CRBSI were estimated using multiple linear regression after adjusting for demographic factors and severity of illness ( APACHE III [ Apache Physiology and Chronic Health Evaluation III ] score ) . RESULTS The incidence of CRBSI per 1000 catheter-days was 3.6 episodes ( 95 % confidence interval [ CI ] , 2.1 - 5.8 episodes ) . Microbiologic isolates were Gram-positive bacteria in 75 % , Gram-negative bacteria in 20 % , and yeast in 5 % . After adjusting for demographic factors and severity of disease , CRBSI was associated with an increase of $ 56 167 ( 95 % CI , $ 11 523-$165 735 ; P = .001 ) ( in 1998 dollars ) in total hospital cost , an increase of $ 71 443 ( 95 % CI , $ 11 960-$195 628 ; P<.001 ) in ICU cost , a 22-day increase in hospital length of stay , and a 20-day increase in ICU length of stay . CONCLUSIONS For critically ill surgical patients , CRBSI is associated with a profound increase in re source use . Prevention , early diagnosis , and intervention for CRBSI might result in cost savings in this high-risk population OBJECTIVE To determine the additional direct costs of hospitalization attributable to catheter-associated urinary tract infection ( CAUTI ) in 1,497 newly catheterized patients . DESIGN Prospect i ve observational and laboratory study . SETTING University hospital . METHODS Data were collected on risk factors for CAUTI  ( defined as > 10(3 ) colony-forming units [CFU]/mL ) , severity of illness , and diagnostic and therapeutic interventions in consenting newly catheterized patients . Daily urine cultures were obtained from each newly catheterized patient , but the results of these cultures were not revealed to his or her physician . During the study , one of the investigators ( DGM ) review ed each patient 's record and made a judgment as to which of the diagnostic tests and treatments ordered and what incremental length of stay could reasonably be ascribed to his or her CAUTI . The total hospital costs for each patient were also obtained . RESULTS Overall , 235 patients acquired CAUTIs during the study ; most of the CAUTIs were completely asymptomatic , and only 52 % were diagnosed by the patients ' physicians using the hospital laboratory . Only 1 patient with a CAUTI had a secondary bloodstream infection . Thirty-three ( 13 % ) of the CAUTIs were caused by Escherichia coli ; 63 ( 25 % ) by Klebsiella , Enterobacter , Citrobacter , Pseudomonas aeruginosa , or other antibiotic-resistant , gram-negative bacilli ; 87 ( 35 % ) by enterococci or staphylococci ; and 67 ( 27 % ) by C and ida species . The 123 CAUTIs diagnosed by the hospital laboratory were judged to have been responsible for an additional $ 20,662 in extra costs of diagnostic tests and $ 35,872 in extra medication costs , a mean of $ 589 ( median , $ 356 ) per CAUTI . CAUTIs caused by E. coli cost considerably less than infections caused by other gram-negative bacilli ( $ 363.3 + /- $ 228.2 vs $ 690.4 + /- $ 783.7 ; P = .02 ) or yeasts ( $ 821.2 + /- $ 2,169.9 ) . There were less striking differences in the costs per CAUTI caused by staphylococci or enterococci ( $ 387.1 + /- $ 434.8 ) . CONCLUSIONS The extra direct costs associated with nosocomial CAUTI found in this prospect i ve study , which was done in the era of managed care during the late 1990s , are substantially lower than those reported in the largest comparable studies done more than 15 years ago , most of which were retrospective , reflecting the powerful impact of cost-containment measures that are now implemented in managed care OBJECTIVE To evaluate changes in the epidemiological features of Clostridium difficile colitis in hospitalized patients in the United States ( C difficile is a common cause of nosocomial diarrhea that has been shown to be increasing in virulence in Canada and across Europe ) . DESIGN Cohort analysis of all patients with C difficile colitis in the Nationwide Inpatient Sample . SETTING Population -based data from the Nationwide Inpatient Sample , a 20 % stratified r and om sample of US hospital discharge abstract s from January 1 , 1993 , through December 31 , 2003 . PATIENTS Using st and ard International Classification of Diseases , Ninth Revision ( ICD-9 ) diagnostic codes , we identified patients with C difficile colitis . We controlled for comorbid conditions by calculating the Deyo modification of the Charlson score . To determine the relationship of year of diagnosis on main outcome measures , we constructed multivariate models . MAIN OUTCOME MEASURES The prevalence , case fatality , total mortality rate , and colectomy rate of C difficile colitis . RESULTS We found that the prevalence , case fatality , total mortality rate , and colectomy rate of C difficile colitis increased from 1993 through 2003 . In our regression analysis , the year of diagnosis predicted an increase in prevalence , case fatality , total mortality rate , and colectomy rate after adjusting for potential confounders . CONCLUSIONS The prevalence , case fatality , total mortality rate , and colectomy rate of C difficile colitis significantly increased from 1993 to 2003 . These findings provide compelling evidence of the changing epidemiological features of C difficile colitis A total of 271 patients were prospect ively followed up to determine whether patients whose hospital stay is complicated by diarrhea due to Clostridium difficile experience differences in cost and length of stay and survival rates when compared with patients whose stay is not complicated by C. difficile-associated diarrhea . Forty patients ( 15 % ) developed nosocomial C. difficile-associated diarrhea . These patients incurred adjusted hospital costs of $ 3669 - -that is , 54 % ( 95 % confidence interval [ CI ] , 17%-103%)--higher than patients whose course was not complicated by C. difficile-associated diarrhea . The extra length of stay attributable to C. difficile-associated diarrhea was 3.6 days ( 95 % CI , 1.5 - 6.2 ) . C. difficile-associated diarrhea was not associated with excess 3-month or 1-year mortality after adjustment for age , comorbidity , and disease severity . On the basis of the findings of this study , a conservative estimate of the cost of this disease in the United States exceeds $ 1.1 billion per year Objective : To determine the attributable cost and length of stay of intensive care unit (ICU)–acquired , catheter-associated bloodstream infections from a hospital-based cost perspective , after adjusting for potential confounders . Design : Patients admitted to the ICU between January 19 , 1998 , and July 31 , 2000 , were observed prospect ively for the occurrence of catheter-associated bloodstream infections . Hospital costs were obtained from the hospital cost accounting data base . Setting : The medical and surgical ICUs at a 500-bed suburban , tertiary care hospital . Patients : Patients requiring central venous catheterization while in the ICU . Interventions : None . Measurements and Main Results : We measured occurrence of catheter-associated bloodstream infection , in-hospital mortality rate , total ICU and hospital lengths of stay , and total hospital costs . Catheter-associated bloodstream infection occurred in 41 of 1,132 patients ( 3.6 cases per 1000 catheter days ) . Patients with catheter-associated bloodstream infection had significantly 
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As hospitals realize savings from prevention of these complications under payment reforms , they may be more likely to invest in such strategies