Adjustment For Severity Of Illness Research Articles

A multicenter study on the clinical outcome of chorioamnionitis in preterm infants

The purpose of this study was to examine the effects of clinical maternal chorioamnionitis on morbidity and mortality rates among infants who are at < 33 weeks of gestation, adjusted for patient characteristics that included admission neonatal illness severity (Score for Neonatal Acute Physiology, version II; SNAP-II). With multivariate logistic regression analysis, prospectively collected hospital outcomes from the Canadian Neonatal Network of singleton infants with birth gestational age of < 33 weeks and clinical chorioamnionitis were compared retrospectively with nonexposed infants. Of 3094 infants, 477 infants (15.4%) who were exposed to clinical chorioamnionitis had significantly higher admission SNAP-II scores. Bivariate analysis revealed that the neonatal mortality rate was increased significantly in the chorioamnionitis group (10.6% vs 6.1%). Multivariate regression analysis with adjustment for illness severity indicated that chorioamnionitis was associated with an increased risk of early sepsis (odds ratio, 5.54; 95% confidence interval, 2.87-10.69) and severe intraventricular hemorrhage (odds ratio, 1.62; 95% confidence interval, 1.17-2.24) but not neonatal death. Preterm infants who are exposed to clinical chorioamnionitis have an increased risk of early-onset sepsis and severe intraventricular hemorrhage.

Racial and ethnic disparities in mortality from acute lung injury.

Little is known about the influence of race and ethnicity on mortality from acute lung injury (ALI). We sought to determine whether black race or Hispanic ethnicity is independently associated with mortality among patients with ALI. Retrospective cohort study of patients enrolled in the Acute Respiratory Distress Syndrome Network randomized controlled trials. Adult intensive care units participating in the Acute Respiratory Distress Syndrome Network trials. A total of 2362 mechanically ventilated patients (1715 white, 449 black, and 198 Hispanic) with ALI. The primary outcome was 60-day mortality. A secondary outcome was number of ventilator-free days. Crude mortality was 33% for both blacks and Hispanics compared with 27% for whites (p = 0.02). After adjusting for demographic and clinical covariates, the association between race/ethnicity and mortality persisted (odds ratio [OR] = 1.42; 95% confidence interval [CI] 1.10-1.84 for blacks; OR = 1.94; 95% CI, 1.36-2.77 for Hispanics; OR = 1.00 for whites). After adjustment for severity of illness (Acute Physiology Score), black race was no longer significantly associated with mortality (OR = 1.25; 95% CI, 0.95-1.66), whereas the association with Hispanic ethnicity persisted (OR = 2.00; 95% CI, 1.37-2.90). Hispanics had significantly fewer ventilator-free days compared with whites after adjustment for demographic and clinical covariates (mean difference in days = -2.3; 95% CI -3.90 to -0.70). Black and Hispanic patients with ALI have a significantly higher risk of death compared with white patients. This increased risk seemed to be mediated by increased severity of illness at presentation for blacks, but was unexplained among Hispanics.

Controlling for Severity of Illness in Outcome Studies Involving Infectious Diseases: Impact of Measurement at Different Time Points

Severity of illness is an important confounder in outcome studies involving infectious diseases. However, it is unclear whether the time at which severity of illness is measured is important. We performed a retrospective study of 328 episodes of gram-negative bacteremia in adult patients to assess the impact of the time of measurement of severity of illness on the association between empirical antimicrobial therapy received and in-hospital mortality. Using a modified Acute Physiology Score (APS), severity of illness was measured at 2 time points: (1) hospital admission and (2) 24 hours before the first culture-positive blood sample was collected. Multivariate logistic regression was used to estimate the impact of adjusting for the APS on the relationship between empirical therapy received (ie, the exposure) and in-hospital mortality (ie, the outcome). The mean APS (+/- standard deviation) of patients with bacteremia increased during their hospital stay (from 19.2 +/- 11.6 at admission to 24.2 +/- 13.6 at the second time point; P < .01). When examining the association between empirical antimicrobial therapy received and in-hospital mortality, and controlling for the APS, there was a trend toward a decreased impact of appropriate therapy received on in-hospital mortality. The unadjusted odds ratio (OR) for the association between appropriate therapy received and in-hospital mortality was 0.83 (95% confidence interval [CI], 0.51-1.34). After controlling for the APS at admission, this association was attenuated (OR, 0.94 [95% CI, 0.57-1.55]), and when a change in the APS was also included in the multivariate logistic regression model, the association was further attenuated (OR, 0.99 [95% CI, 0.58-1.69]). The magnitude of the association between appropriate antimicrobial therapy received and in-hospital mortality among patients with gram-negative bacteremia was sensitive to the timing of adjustment for severity of illness.

Obesity and Symptom Burden in Family Medicine Patients

Medical visits are initiated by patients in search of symptom relief. The extent to which obesity independently increases the risk of common symptoms is unknown. To assess how obesity affects symptom burden among family medicine patients, after adjustment for severity of illness, via retrospective analysis of electronic medical records pertaining to 1738 adult family medicine patients treated in a large family medicine department in Rochester, Minnesota, USA. A symptom index was used to measure symptom burden. Body mass index (BMI; kg/m) was measured during clinic visits. Multiple logistic regression analysis was used to test for an independent relationship between BMI category and the presence of three or more common symptoms. Adjusting for co-morbidity and other confounders using multiple logistic regression analysis revealed that having a BMI ≥35kg/m was independently related to symptom burden (adjusted odds ratio [OR] = 1.80; 95% CI 1.24, 2.63). Patients with low and moderate co-morbidities (as measured by the Charlson Co-morbidity Index) also had higher odds of reporting more symptoms (OR = 1.60; 95% CI 1.17, 2.17 and OR = 1.87; 95% CI 1.36, 2.56, respectively). Symptom burden increased with age. Odds of having three or more symptoms were lower for married patients (OR 0.63; 95% CI 0.47, 0.83). In our sample of family medicine patients, increased symptom burden may be associated with a BMI ≥35kg/m. Lower levels of obesity do not appear to be related to symptom burden.

Correlation between case mix index and antibiotic use in hospitals

To compare the quantitative antibiotic use between hospitals or hospital units and to explore differences, adjustment for severity of illness of hospitalized patients is essential. The case mix index (CMI) is an economic surrogate marker (i.e. the total cost weights of all inpatients per a defined time period divided by the number of admissions) to describe the average patients' morbidity of individual hospitals. We aimed to investigate the correlation between CMI and hospital antibiotic use. We used weighted linear regression analysis to evaluate the correlation between in-hospital antibiotic use in 2006 and CMI of 18 departments of the tertiary care University Hospital Zurich and of 10 primary and 2 secondary acute care hospitals in the Canton of Zurich in Switzerland. Antibiotic use varied substantially between different departments of the university hospital [defined daily doses (DDD)/100 bed-days, 68.04; range, 20.97-323.37] and between primary and secondary care hospitals (range of DDD/100 bed-days, 15.45-57.05). Antibiotic use of university hospital departments and the different hospitals, respectively, correlated with CMI when calculated in DDD/100 bed-days [coefficient of determination (R(2)), 0.57 (P = 0.0002) and 0.46 (P = 0.0065)], as well as when calculated in DDD/100 admissions [R(2), 0.48 (P = 0.0008) and 0.85 (P < 0.0001), respectively]. Antibiotic use correlated with CMI across various specialties of a university hospital and across different acute care hospitals. For benchmarking antibiotic use within and across hospitals, adjustment for CMI may be a useful tool in order to take into account the differences in hospital category and patients' morbidities.

Association between critical care physician management and patient mortality in the intensive care unit.

Critically ill patients admitted to intensive care units (ICUs) are thought to gain an added survival benefit from management by critical care physicians, but evidence of this benefit is scant. To examine the association between hospital mortality in critically ill patients and management by critical care physicians. Retrospective analysis of a large, prospectively collected database of critically ill patients. 123 ICUs in 100 U.S. hospitals. 101,832 critically ill adults. Through use of a random-effects logistic regression, investigators compared hospital mortality between patients cared for entirely by critical care physicians and patients cared for entirely by non-critical care physicians. An expanded Simplified Acute Physiology Score was used to adjust for severity of illness, and a propensity score was used to adjust for differences in the probability of selective referral of patients to critical care physicians. Patients who received critical care management (CCM) were generally sicker, received more procedures, and had higher hospital mortality rates than those who did not receive CCM. After adjustment for severity of illness and propensity score, hospital mortality rates were higher for patients who received CCM than for those who did not. The difference in adjusted hospital mortality rates was less for patients who were sicker and who were predicted by propensity score to receive CCM. Residual confounders for illness severity and selection biases for CCM might exist that were inadequately assessed or recognized. In a large sample of ICU patients in the United States, the odds of hospital mortality were higher for patients managed by critical care physicians than those who were not. Additional studies are needed to further evaluate these results and clarify the mechanisms by which they might occur.

Acquired Weakness, Handgrip Strength, and Mortality in Critically Ill Patients

ICU-acquired paresis (ICUAP) is common in survivors of critical illness. There is significant associated morbidity, including prolonged time on the ventilator and longer hospital stay. However, it is unclear whether ICUAP is independently associated with mortality, as sicker patients are more prone and existing studies have not adjusted for this. To test the hypothesis that ICUAP is independently associated with increased mortality. Secondarily, to determine if handgrip dynamometry is a concise measure of global strength and is independently associated with mortality. A prospective multicenter cohort study was conducted in intensive care units (ICU) of five academic medical centers. Adults requiring at least 5 days of mechanical ventilation without evidence of preexisting neuromuscular disease were followed until awakening and were then examined for strength. We measured global strength and handgrip dynamometry. The primary outcome was in-hospital mortality and secondary outcomes were hospital and ICU-free days, ICU readmission, and recurrent respiratory failure. Subjects with ICUAP (average MRC score of < 4) had longer hospital stays and required mechanical ventilation longer. Handgrip strength was lower in subjects with ICUAP and had good test performance for diagnosing ICUAP. After adjustment for severity of illness, ICUAP was independently associated with hospital mortality (odds ratio [OR], 7.8; 95% confidence interval [CI], 2.4-25.3; P = 0.001). Separately, handgrip strength was independently associated with hospital mortality (OR, 4.5; 95% CI, 1.5-13.6; P = 0.007). ICUAP is independently associated with increased hospital mortality. Handgrip strength is also independently associated with poor hospital outcome and may serve as a simple test to identify ICUAP. Clinical trial registered with www.clinicaltrials.gov (NCT00106665).

Hyperglycemia and the Outcome of Pediatric Cardiac Surgery Patients Requiring Peritoneal Dialysis

To study the nature of the association between glycemia and ICU mortality in pediatric cardiac surgery patients treated with peritoneal dialysis (PD). Retrospective observational study in the ICU of a tertiary hospital involving forty pediatric cardiac surgery patients treated with PD. We selected patients requiring PD, extracted glucose measurements and nutritional intake data during ICU stay and calculated mean and maximum blood glucose values i) during ICU stay; ii) during dependence on PD; and iii) during independence from PD. We statistically assessed the relationship between glycemia-related variables and ICU mortality. Twenty-two patients treated with PD died (mortality 55%). In the PD cohort, 9725 blood glucose measurements were performed (every 3.3 hours on average). The mean glycemia during dependence on PD was significantly higher in non-survivors than survivors (p<0.0001), but not during independence from PD (p=0.49). The area under the receiver operator characteristic curve for the mean glycemia during dependence on PD was significantly greater than that obtained during independence from PD. Even after adjustment for severity of illness using multivariate logistic analysis, the mean glycemia and calorie intake during PD were significant and independent predictors of ICU mortality. A higher mean blood glucose concentration during PD, but not during PD-free periods was associated with greater ICU mortality. Mean glycemia and calorie intake during PD were significant and independent predictors of ICU mortality.

Impact of the More-Potent Antibiotics Quinupristin-Dalfopristin and Linezolid on Outcome Measure of Patients with Vancomycin-Resistant Enterococcus Bacteremia

The impact of antibiotic resistance on the clinical outcome of patients with vancomycin-resistant Enterococcus (VRE) bacteremia remains unclear. There are limited data comparing patient outcomes during the early era of vancomycin resistance with the period of more-potent antibiotic availability. A retrospective review was conducted of 113 patients with VRE bacteremia at a single institution from August 1993 to September 2005. Patients were assigned to a group on the basis of initial antibiotic choice for treatment of VRE (linezolid, quinupristin-dalfopristin, or combinations of other agents, before newer options were available). Outcome measurements were examined for the initial episode of VRE bacteremia, and multiple logistic regression analysis was performed to compare group outcomes. Overall mortality was 37.2% (42 of 113 patients). VRE bacteremia caused or significantly contributed to death in 29 (69%) of 42 patients. Seventy-one patients were initially treated with linezolid, 20 with quinupristin-dalfopristin, and 22 with combinations of other agents. Univariate analysis indicated significantly more deaths in the quinupristin-dalfopristin group (odds ratio, 5.45; 95% confidence interval, 1.89-15.9) and in the other-agents group (odds ratio, 2.94; 95% confidence interval, 1.09-7.94) than in the linezolid group. However, after adjustment for severity of illness, treatment group was not a significant independent factor. Despite the development of antimicrobial agents with greater potency against VRE, a significant change in clinical outcome was not observed. This suggests that vancomycin resistance does not significantly influence mortality and points to the continued need for prospective, randomized clinical trials.

Physical limitations and self-rated overall health in family medicine patients

Objective: To assess how physical limitations relate to self-rated health among family medicine patients after adjustment for severity of illness. Design: A telephone survey of family medicine patients, linked with medical record information. Setting: A large family medicine department in Rochester, Minnesota, USA. Subjects: Self-ratings of health were linked to medical records for 804 adult patients. Results: Adjusting for severity and other confounders using multiple logistic regression analysis revealed that having physical limitations was inversely and independently related to good self-rated health (adjusted odds ratio = 0.20, P<0.001). Odds ratios also were lower for high severity of illness (adjusted odds = 0.43). Morbidly obese patients and patients older than 65 years of age also had reduced odds of good self-rated health. Conclusions: In our sample of family medicine patients, part of the disparity in health status experienced by people with physical limitations is attributable to greater severity of illness, age and obesity.

Sex-and age-based differences in the delivery and outcomes of critical care

Previous studies have suggested that a patient's sex may influence the provision and outcomes of critical care. Our objective was to determine whether sex and age are associated with differences in admission practices, processes of care and clinical outcomes for critically ill patients. We used a retrospective cohort of 466,792 patients, including 24,778 critically ill patients, admitted consecutively to adult hospitals in Ontario between Jan. 1, 2001, and Dec. 31, 2002. We measured associations between sex and age and admission to the intensive care unit (ICU); use of mechanical ventilation, dialysis or pulmonary artery catheterization; length of stay in the ICU and hospital; and death in the ICU, hospital and 1 year after admission. Of the 466,792 patients admitted to hospital, more were women than men (57.0% v. 43.0% for all admissions, p < 0.001; 50.1% v. 49.9% for nonobstetric admissions, p < 0.001). However, fewer women than men were admitted to ICUs (39.9% v. 60.1%, p < 0.001); this difference was most pronounced among older patients (age > or = 50 years). After adjustment for admission diagnoses and comorbidities, older women were less likely than older men to receive care in an ICU setting (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.66-0.71). After adjustment for illness severity, older women were also less likely than older men to receive mechanical ventilation (OR 0.91, 95% CI 0.81-0.97) or pulmonary artery catheterization (OR 0.80, 95% CI 0.73-0.88). Despite older men and women having similar severity of illness on ICU admission, women received ICU care for a slightly shorter duration yet had a longer length of stay in hospital (mean 18.3 v. 16.9 days; p = 0.006). After adjustment for differences in comorbidities, source of admission, ICU admission diagnosis and illness severity, older women had a slightly greater risk of death in the ICU (hazard ratio 1.20, 95% CI 1.10-1.31) and in hospital (hazard ratio 1.08, 95% CI 1.00-1.16) than did older men. Among patients 50 years or older, women appear less likely than men to be admitted to an ICU and to receive selected life-supporting treatments and more likely than men to die after critical illness. Differences in presentation of critical illness, decision-making or unmeasured confounding factors may contribute to these findings.

After-hours admissions are not associated with increased risk-adjusted mortality in pediatric intensive care

To examine the influence of time of admission on risk-adjusted mortality and length of stay for nonelective patients admitted to a pediatric intensive care unit (ICU) without 24-h per day in-house intensivist coverage. Data analyzed came from a comprehensive, prospectively collected ICU database. A 12-bed pediatric ICU located in a university-affiliated tertiary referral children's hospital. Subjects consisted of 4,456 consecutive nonelective patients admitted over a 10-year period (1997-2006). None. Patients were categorized according to time of admission to the ICU as either in-hours (0800-1800 Monday-Friday and 0800-1200 on weekends), when an intensivist is present in the ICU, or after-hours (all other times), when intensivists attend only on an as-needed basis. Multivariate logistic regression was used to assess the effect of time of admission on outcome after adjustment for severity of illness using the Paediatric Index of Mortality (PIM). Patients admitted after hours had a lower risk-adjusted mortality than those admitted during normal working hours, with an odds ratio for death of 0.712 (95% confidence interval 0.518-0.980, p = 0.037). Length of stay was also significantly shorter for patients admitted after hours (44.05h vs. 50.0h, p = 0.001). A lack of in-house intensivist presence is not associated with any increase in mortality or length of stay for patients admitted to our pediatric ICU; on the contrary, after-hours admission in this cohort was associated with a decreased risk-adjusted mortality and a shorter length of stay.

Is hyperglycemia really harmful? A critical appraisal of “Persistent hyperglycemia in critically ill children” by Faustino and Apkon (J Pediatr 2005; 146:30–34)

To review the findings and to discuss the implications of hyperglycemia in critically ill children. A critical appraisal of an article with literature review. In this single-center, retrospective cohort study, the authors report that the prevalence of hyperglycemia ranged from 16.7% to 75%, depending on the cutoff values (120 mg/dL, 150 mg/dL, and 200 mg/dL), among nondiabetic children admitted to a pediatric intensive care unit. Hyperglycemia correlated with an increased in-hospital mortality rate (relative risk, 2.5; 95% confidence interval, 1.26-4.93 for maximum glucose within 24 hrs, >150 mg/dL; and relative risk, 5.68; 95% confidence interval, 1.38-23.47 for highest glucose within 10 days, >120 mg/dL), as well as a longer length of stay in the pediatric intensive care unit. This finding is in concordance with other adult and pediatric studies. However, without adjustment for severity of illness, the study does not distinguish cause and effect, nor does it address the role of strict glucose control in this group of patients. This study adds to the growing body of knowledge that associates the timing, intensity, duration, and variability of glycemia with outcomes in critically ill children. However, its limitations restrict drawing causal relationships and prevents insights regarding therapy.

Two Studies Feed the Debate on Active Surveillance for Methicillin‐ResistantStaphylococcus aureusand Vancomycin‐Resistant Enterococci Carriage: To Screen or Not to Screen?

[5] are but a few examples. Two of the more prominent antibiotic-resistant pathogens are methicillin-resistant Staphylococcus aureus (MRSA) and vancomycinresistant enterococci (VRE). According to a recent report from the National Nosocomial Infections Surveillance system of the US Centers for Disease Control and Prevention (CDC), MRSA accounted for nearly 60% of all nosocomial S. aureus infections in intensive care units (ICUs), whereas 29% of enterococcal infections in this population were caused by vancomycin-resistant species [6]. Infection with either pathogen leads to substantial morbidity and mortality, even compared with infection with their antibiotic-sensitive counterparts. MRSA infections have been associated with more prolonged hospitalizations, higher costs, and higher mortality than methicillin-sensitive S. aureus infections [7-10]. VRE, which is sometimes wrongly considered to be a minor pathogen, can also cause substantial morbidity. Bacteremia caused by VRE, after adjustment for severity of illness, is associated with higher recurrence, mortality, and excess costs than vancomycin-sensitive enterococcal infection [11-13]. Individuals can become colonized with

Impact of intensive care unit discharge time on patient outcome

To determine the impact of nighttime intensive care unit (ICU) discharge on patient outcome. Multiple-center, retrospective observational cohort study. Canadian hospitals. We used a prospectively collected dataset containing information on 79,090 consecutive admissions from 31 Canadian community and teaching hospitals. None. Patients were categorized according to the time of ICU discharge into daytime (07:00-20:59) and nighttime (21:00-06:59). Admissions were excluded if the patients were a) </=16 yrs of age (392); b) admitted following cardiac surgery (6,641); c) admitted following the initial admission for patients readmitted to the ICU within the same hospital stay (3,632); d) admitted due to a lack of available ward or specialty care beds (457); or c) transferred to another acute care facility (7,724). We found that 62,056 patients were discharged to the ward following the initial ICU admission. Of the 47,062 discharges eligible for analyses, 10.1% were discharged at night. The unadjusted odds of death for patients discharged from ICU at night was 1.35 (95% confidence interval, 1.23, 1.49), compared with patients discharged during the daytime. After adjustment for illness severity, source, case-mix, age, gender, and hospital size, the mortality risk was increased by 1.22-fold (95% confidence interval, 1.10, 1.36) for nighttime discharges. Multivariate regression analysis revealed that patients discharged from the ICU at night have a significantly shorter ICU length of stay than those discharged during the day (p < .001). Whereas hospital length of stay was similar for daytime and nighttime discharges who survived hospital stay, patients discharged at night who did not survive hospital stay had a significantly shorter hospital length of stay (p = .002). Patients discharged from the ICU at night have an increased risk of mortality compared with those discharged during the day.

Regional citrate versus systemic heparin anticoagulation for continuous renal replacement in critically ill patients

We determined the effect of regional citrate versus systemic heparin anticoagulation for continuous renal replacement therapy in critically ill subjects suffering from acute renal failure who were not at high risk for hemorrhagic complications. Between April 1999 and June 2002, 30 critically ill subjects requiring continuous renal replacement therapy and using 79 hemofilters were randomly assigned to receive regional citrate or systemic heparin anticoagulation. The median hemofilter survival time was 124.5 hours (95% CI 95.3 to 157.4) in the citrate group, which was significantly longer than the 38.3 hours (95% CI 24.8 to 61.9) in the heparin group (P < 0.001). Increasing illness severity score, male gender, and decreasing antithrombin-III levels were independent predictors of an increased relative hazard of hemofilter failure. After adjustment for illness severity, antithrombin-III levels increased significantly more over the period of study in the citrate as compared to the heparin group (P= 0.038). Moreover, after adjustment for antithrombin-III levels and illness severity score, the relative risk of hemorrhage with citrate anticoagulation was significantly lower than that with heparin (relative risk of 0.14; 95% CI 0.02 to 0.96, P= 0.05). Compared with systemic heparin anticoagulation, regional citrate anticoagulation significantly increases hemofilter survival time, and significantly decreases bleeding risk in critically ill patients suffering from acute renal failure and requiring continuous renal replacement therapy.

Treatment Intensity and Outcome of Patients Aged 80 and Older in Intensive Care Units: A Multicenter Matched‐Cohort Study

To determine whether patients aged 80 and older have similar treatment intensity to that of younger patients in the intensive care unit (ICU). Multicenter, matched-cohort study. Data were extracted from a multicenter database with 36 ICUs in the Paris area (France) during a 4-year period (1997-2000). Three thousand one hundred seventy-five patients aged 80 and older (oldest-old) were retrospectively matched to 3,175 patients aged 65 to 79 (young-old). The matching criteria were severity status on admission (+/-2) (assessed using a corrected Simplified Acute Physiology Score II leaving out age points), Charlson Comorbidity Index, type of admission (surgical vs medical), sex, admission to same ICU, and year of ICU admission. The underlying condition was classified using the McCabe classification. The functional status was assessed using the Knaus classification. The ICU workload was assessed using the OMEGA scoring system. Total and daily workload were lower in the oldest-old than in matched young-old patients. Estimated mean direct medical cost per stay was approximately 1,280 dollars lower for oldest-old patients. Older patients received less mechanical ventilation (adjusted odds ratio (AOR)=0.69, 95% confidence interval (CI)=0.61-0.78), less tracheostomy (AOR=0.37, 95% CI=0.28-0.50), and less renal support (AOR=0.52, 95% CI=0.41-0.66) than matched young-old patients. Oldest-old patients had a shorter length of ICU stay than matched young-old patients and the same length of post-ICU stay. Oldest-old patients receive less treatment in the ICU than young-old patients even after adjustment for severity of illness.

Antimicrobial use and the influence of inadequate empiric antimicrobial therapy on the outcomes of nosocomial bloodstream infections in a neonatal intensive care unit.

To evaluate antimicrobial use and the influence of inadequate empiric antimicrobial therapy on the outcomes of nosocomial bloodstream infections (BSIs). Prospective cohort study with nested case-control analysis. Neonatal intensive care unit (NICU). All patients weighing 2,000 g or less were enrolled. Data collection included risk factors for nosocomial BSI, admission severity of illness, microbiology, antimicrobial therapy, and outcomes. Inadequate empiric antimicrobial therapy was defined as the use of antibiotics for more than 48 hours after the day that blood cultures were performed that did not cover the microorganisms causing the bacteremia or administration of antibiotics that failed to cover resistant microorganisms. Two hundred twenty-nine patients were enrolled. Forty-five developed nosocomial BSIs. The BSI rates were 11.2, 2.8, and 0 per 1,000 catheter-days for patients weighing 1,000 g or less, between 1,001 and 1,500 g, and between 1,501 and 2,000 g, respectively. After adjustment for severity of illness, the mortality in patients with nosocomial BSI receiving inadequate empiric antimicrobial therapy was higher than in those receiving adequate therapy (adjusted odds ratio [AOR], 5.3; 95% confidence interval [CI95], 1.2-23.2). By multivariate analysis, nosocomial BSI attributed to Candida species (AOR, 6.3; CI95, 1.4-28.0) and invasive procedure prior to onset of BSI (AOR, 6.4; CI95, 1.0-39.0) were associated with administration of inadequate empiric antimicrobial therapy. Administration of inadequate empiric antimicrobial therapy among NICU patients with nosocomial BSI was associated with higher mortality. Additional studies on the role of inadequate empiric antimicrobial therapy and the outcomes of BSIs among NICU patients are needed.

Acute severe asthma: Outcome and Medicaid insurance.

OBJECTIVE: Economically disadvantaged children receive less preventive asthma care and more inpatient care. Studies have not evaluated the association of insurance status on children with severe exacerbations. We evaluated differences in severity of illness, resource use, and outcome associated with Medicaid insurance among children receiving intensive care for asthma. DESIGN: Retrospective cohort study. SETTING: Fourteen American pediatric intensive care units participating in the Pediatric Intensive Care Evaluations database. Methods: Patients with a primary diagnosis of asthma treated from May 1995 to February 2000 were identified. Demographic information and clinical data were evaluated to determine whether there was an association between Medicaid insurance, severity of illness, and length of stay. RESULTS: Twenty-six percent of the children had Medicaid insurance; 22% of children with Medicaid insurance received mechanical ventilation compared with 15% of those with commercial insurance and 16% in a health maintenance organization. After adjustment for severity of illness (Pediatric Risk of Mortality III and use of invasive therapies), Medicaid insurance was significantly associated with increased length of stay in the intensive care unit and hospital. Among children who received mechanical ventilation, patients with Medicaid also received ventilator support significantly longer. CONCLUSIONS: Asthmatic children receiving Medicaid had longer pediatric intensive care unit and hospital stays and an increased risk of mechanical ventilation compared with asthmatic children with commercial or health maintenance organization insurance. Further studies are needed to evaluate differences in outcome and resource utilization for economically disadvantaged asthmatic children.

The relation between managed care market share and the treatment of elderly fee-for-service patients with myocardial infarction

Purpose To determine if greater managed care market share is associated with greater use of recommended therapies for fee-for-service patients with acute myocardial infarction. Subjects and methods We examined the care of 112 900 fee-for-service Medicare beneficiaries aged ≥65 years who resided in one of 320 metropolitan statistical areas and who were admitted with an acute myocardial infarction between February 1994 through July 1995. Use of recommended medical treatments and 30-day survival were determined for areas with low (<10%), medium (10% to 30%), and high (>30%) managed care market share. Results After adjustment for severity of illness, teaching status of the admission hospital, and area characteristics, areas with high levels of managed care had greater use of beta-blockers (relative risk [RR] for greater use = 1.18; 95% confidence interval [CI]: 1.06 to 1.29) and aspirin at discharge (RR = 1.05; 95% CI: 1.02 to 1.07), but less appropriate coronary angiography (RR = 0.93; 95% CI: 0.86 to 1.01) and reperfusion (RR = 0.95; 95% CI: 0.85 to 1.03) when compared with areas with low levels of managed care. Conclusions Medicare beneficiaries with fee-for-service insurance who resided in areas with high managed care activity were more likely to have received appropriate treatment with beta-blockers and aspirin, and less likely to have undergone coronary angiography following admission for myocardial infarction. Thus, the effects of managed care may not be limited to managed care enrollees.