Health Care-Associated Infections Among Hospitalized Patients With COVID-19, March 2020-March 2022.

Importance: The reported incidence of many health care-associated infections (HAIs) increased during the COVID-19 pandemic; however, it is unclear whether this is due to increased patient risk or to increased pressure on the health care system. Objective: To assess HAI occurrence among patients admitted to hospitals with and without COVID-19. Design, Setting, and Participants: A cross-sectional retrospective analysis of inpatients discharged both with and without laboratory-confirmed COVID-19 infection was conducted. Data were obtained between January 1, 2019, and March 31, 2022, from community hospitals affiliated with a large health care system in the US. Exposure: COVID-19 infection. Main Outcomes and Measures: Occurrence of central line-associated bloodstream infection (CLABSI), catheter-associated urinary tract infection (CAUTI), methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, and Clostridioides difficile infection as reported to the National Healthcare Safety Network. Results: Among nearly 5 million hospitalizations in 182 hospitals between 2020 and 2022, the occurrence of health care-associated infections (HAIs) was high among the 313 200 COVID-19 inpatients (median [SD] age, 57 [27.3] years; 56.0% women). Incidence per 100 000 patient-days showed higher HAIs among those with COVID-19 compared with those without. For CLABSI, the incidence for the full 9 quarters of the study was nearly 4-fold higher among the COVID-19 population than the non-COVID-19 population (25.4 vs 6.9). For CAUTI, the incidence in the COVID-19 population was 2.7-fold higher in the COVID-19 population (16.5 vs 6.1), and for MRSA, 3.0-fold higher (11.2 vs 3.7). Quarterly trends were compared with the same quarter in 2019. The greatest increase in the incidence of HAI in comparison with the same quarter in 2019 for the entire population occurred in quarter 3 of 2020 for CLABSI (11.0 vs 7.3), quarter 4 of 2021 for CAUTI (7.8 vs 6.8), and quarter 3 of 2021 for MRSA (5.2 vs 3.9). When limited to the non-COVID-19 population, the increase in CLABSI incidence vs the 2019 incidence was eliminated, and the quarterly rates of MRSA and CAUTI were lower vs the prepandemic 2019 comparator quarter. Conclusions and Relevance: In this cross-sectional study of hospitals during the pandemic, HAI occurrence among inpatients without COVID-19 was similar to that during 2019 despite additional pressures for infection control and health care professionals. The findings suggest that patients with COVID-19 may be more susceptible to HAIs and may require additional prevention measures.

Discontinuation of atorvastatin use in hospital is associated with increased risk of mortality in COVID-19 patients.

BACKGROUND: Statins are a commonly used class of drugs, and reports have suggested that their use may affect COVID-19 disease severity and mortality risk. OBJECTIVE: The purpose of this analysis was to determine the effect of discontinuation of previous atorvastatin therapy in patients hospitalized for COVID-19 on the risk of mortality and ventilation. METHODS: Data from 146,413 hospitalized COVID-19 patients were classified according to statin therapy. Home + in hospital atorvastatin use (continuation of therapy); home + no in hospital atorvastatin use (discontinuation of therapy); no home + no in hospital atorvastatin use (no statins). Logistic regression was performed to assess the association between atorvastatin administration and either mortality or use of mechanical ventilation during the encounter. RESULTS: Continuous use of atorvastatin (home and in hospital) was associated with a 35% reduction in the odds of mortality compared to patients who received atorvastatin at home but not in hospital (odds ratio [OR]: 0.65, 95% confidence interval [CI]: 0.59-0.72, p < .001). Similarly, the odds of ventilation were lower with continuous atorvastatin therapy (OR: 0.70, 95% CI: 0.64-0.77, p < .001). CONCLUSIONS: Discontinuation of previous atorvastatin therapy is associated with worse outcomes for COVID-19 patients. Providers should consider maintaining existing statin therapy for patients with known or suspected previous use.

The Impact of Coronavirus Disease 2019 (COVID-19) on Healthcare-Associated Infections.

BACKGROUND: The profound changes wrought by coronavirus disease 2019 (COVID-19) on routine hospital operations may have influenced performance on hospital measures, including healthcare-associated infections (HAIs). We aimed to evaluate the association between COVID-19 surges and HAI and cluster rates. METHODS: In 148 HCA Healthcare-affiliated hospitals, from 1 March 2020 to 30 September 2020, and a subset of hospitals with microbiology and cluster data through 31 December 2020, we evaluated the association between COVID-19 surges and HAIs, hospital-onset pathogens, and cluster rates using negative binomial mixed models. To account for local variation in COVID-19 pandemic surge timing, we included the number of discharges with a laboratory-confirmed COVID-19 diagnosis per staffed bed per month. RESULTS: Central line-associated blood stream infections (CLABSI), catheter-associated urinary tract infections (CAUTI), and methicillin-resistant Staphylococcus aureus (MRSA) bacteremia increased as COVID-19 burden increased. There were 60% (95% confidence interval [CI]: 23-108%) more CLABSI, 43% (95% CI: 8-90%) more CAUTI, and 44% (95% CI: 10-88%) more cases of MRSA bacteremia than expected over 7 months based on predicted HAIs had there not been COVID-19 cases. Clostridioides difficile infection was not significantly associated with COVID-19 burden. Microbiology data from 81 of the hospitals corroborated the findings. Notably, rates of hospital-onset bloodstream infections and multidrug resistant organisms, including MRSA, vancomycin-resistant enterococcus, and Gram-negative organisms, were each significantly associated with COVID-19 surges. Finally, clusters of hospital-onset pathogens increased as the COVID-19 burden increased. CONCLUSIONS: COVID-19 surges adversely impact HAI rates and clusters of infections within hospitals, emphasizing the need for balancing COVID-related demands with routine hospital infection prevention.

Real-World Effectiveness of Remdesivir in Adults Hospitalized With Coronavirus Disease 2019 (COVID-19): A Retrospective, Multicenter Comparative Effectiveness Study.

BACKGROUND: There is an urgent need to understand the real-world effectiveness of remdesivir in the treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: This was a retrospective comparative effectiveness study. Individuals hospitalized in a large private healthcare network in the United States from 23 February 2020 through 11 February 2021 with a positive test for SARS-CoV-2 and ICD-10 diagnosis codes consistent with symptomatic coronavirus disease 2019 (COVID-19) were included. Remdesivir recipients were matched to controls using time-dependent propensity scores. The primary outcome was time to improvement with a secondary outcome of time to death. RESULTS: Of 96 859 COVID-19 patients, 42 473 (43.9%) received at least 1 remdesivir dose. The median age of remdesivir recipients was 65 years, 23 701 (55.8%) were male, and 22 819 (53.7%) were non-White. Matches were found for 18 328 patients (43.2%). Remdesivir recipients were significantly more likely to achieve clinical improvement by 28 days (adjusted hazard ratio [aHR] 1.19, 95% confidence interval [CI], 1.16-1.22). Remdesivir patients on no oxygen (aHR 1.30, 95% CI, 1.22-1.38) or low-flow oxygen (aHR 1.23, 95% CI, 1.19-1.27) were significantly more likely to achieve clinical improvement by 28 days. There was no significant impact on the likelihood of mortality overall (aHR 1.02, 95% CI, .97-1.08). Remdesivir recipients on low-flow oxygen were significantly less likely to die than controls (aHR 0.85, 95% CI, .77-.92; 28-day mortality 8.4% [865 deaths] for remdesivir patients, 12.5% [1334 deaths] for controls). CONCLUSIONS: These results support the use of remdesivir for hospitalized COVID-19 patients on no or low-flow oxygen. Routine initiation of remdesivir in more severely ill patients is unlikely to be beneficial.

Reactions and COVID-19 disease progression following SARS-CoV-2 monoclonal antibody infusion.

SARS-CoV-2 monoclonal antibodies (mAbs) have been proposed as a treatment for mild to moderate COVID-19, with favorable outcomes reported in clinical trials and an emergency use authorization granted by the Food and Drug Administration. Real-world data remain limited, however, and thus this analysis presents findings from over 6,500 outpatient administrations of mAb at facilities affiliated with a large healthcare organization in the United States. Within 48 hours of mAb infusion, 15.6% (1,043) of patients received a drug that was indicative of a possible reaction to the infusion; the majority of these were mild (e.g., acetaminophen). Approximately 5.2% of patients who received mAb (n=347) had a post-infusion emergency department visit or admission for COVID-19 disease progression. The results of this analysis indicate that patients who receive mAb have a low likelihood of both an immediate negative reaction to the treatment as well as future inpatient admission related to COVID-19 disease progression.

Hyperglycaemia increases mortality risk in non-diabetic patients with COVID-19 even more than in diabetic patients.

AIM: Diabetes has been identified as a risk factor for poor outcomes in patients with COVID-19. We examined the association of hyperglycaemia, both in the presence and absence of pre-existing diabetes, with severity and outcomes in COVID-19 patients. METHODS: Data from 74,148 COVID-19-positive inpatients with at least one recorded glucose measurement during their inpatient episode were analysed for presence of pre-existing diabetes diagnosis and any glucose values in the hyperglycaemic range (>180 mg/dl). RESULTS: Among patients with and without a pre-existing diabetes diagnosis on admission, mortality was substantially higher in the presence of high glucose measurements versus all measurements in the normal range (70-180 mg/dl) in both groups (non-diabetics: 21.7% vs. 3.3%; diabetics 14.4% vs. 4.3%). When adjusting for patient age, BMI, severity on admission and oxygen saturation on admission, this increased risk of mortality persisted and varied by diabetes diagnosis. Among patients with a pre-existing diabetes diagnosis, any hyperglycaemic value during the episode was associated with a substantial increase in the odds of mortality (OR: 1.77, 95% CI: 1.52-2.07); among patients without a pre-existing diabetes diagnosis, this risk nearly doubled (OR: 3.07, 95% CI: 2.79-3.37). CONCLUSION: This retrospective analysis identified hyperglycaemia in COVID-19 patients as an independent risk factor for mortality after adjusting for the presence of diabetes and other known risk factors. This indicates that the extent of glucose control could serve as a mechanism for modifying the risk of COVID-19 morality in the inpatient environment.

Universal Protection: Operationalizing Infection Prevention Guidance in the COVID-19 Era.

INTRODUCTION: The COVID-19 pandemic has required facilities to quickly respond to a myriad of infection prevention recommendations, as well as design their own protocols. The varied and changing guidance has been difficult for staff to absorb and has presented challenges for managing compliance. APPROACH: HCA Healthcare recognized the need for a coordinated approach to managing infection prevention guidance during the COVID-19 pandemic and a mechanism for monitoring compliance and responding to implementation challenges remotely. This innovation consisted of a bundle of infection prevention guidance referred to as the Universal Protection Framework that collated existing recommendations into an easy-to-understand structure with four domains: core infection prevention practices, access control, distancing, and patient flow. This was supported by education and clear communication. A remote monitoring program that incorporated a combination of report review and virtual observation via videoconferencing using an on-site leader as a navigator for the discussion assessed 46 survey domains for compliance. RESULTS: This framework was implemented in a large health care system, and to date compliance has been monitored at 15 facilities. Overall, compliance was high (average, 90%). High compliance was seen with oversight and distribution of personal protective equipment, cohorting of COVID-19 patients, facility access controls, and employee exposure monitoring. Challenges were identified in compliance with social distancing and universal masking. CONCLUSION: Complex infection prevention expectations for COVID-19 can be communicated and implemented by bundling into a simple framework. This innovation also demonstrated that compliance can be measured remotely, which may be useful even after the pandemic challenges have passed.

No clinical benefit in mortality associated with hydroxychloroquine treatment in patients with COVID-19.

BACKGROUND: The use of hydroxychloroquine (HCQ), with or without concurrent administration of azithromycin (AZM), for treatment of COVID-19 has received considerable attention. The purpose of this study was to determine whether HCQ administration is associated with improved mortality in COVID-19 patients. METHODS: We conducted a retrospective analysis of data collected during the care process for COVID-19 positive patients discharged from facilities affiliated with a large healthcare system in the United States as of April 27, 2020. Patients were categorized by treatment with HCQ (in addition to standard supportive therapy) or receipt of supportive therapy with no HCQ. Patient outcomes were evaluated for in-hospital mortality. Patient demographics and clinical characteristics were accounted for through a multivariable regression analysis. RESULTS: A total of 1669 patients were evaluated (no HCQ, n = 696; HCQ, n = 973). When adjusting for patient characteristics, receipt of AZM, and severity of disease at admission, there was no beneficial effect of receipt of HCQ on the risk of death. In this population, there was an 81% increase in the risk of mortality among patients who received HCQ at any time during their hospital stay versus no HCQ exposure (OR: 1.81, 95% CI: 1.20-2.77, p = 0.01). CONCLUSIONS: In this retrospective analysis, we found that there was no benefit of administration of HCQ on mortality in COVID-19 patients. These results support recent changes to clinical trials that discourage the use of HCQ in COVID-19 patients.

Patient characteristics and admitting vital signs associated with coronavirus disease 2019 (COVID-19)-related mortality among patients admitted with noncritical illness.

OBJECTIVE: To determine risk factors for mortality among COVID-19 patients admitted to a system of community hospitals in the United States. DESIGN: Retrospective analysis of patient data collected from the routine care of COVID-19 patients. SETTING: System of >180 acute-care facilities in the United States. PARTICIPANTS: All admitted patients with positive identification of COVID-19 and a documented discharge as of May 12, 2020. METHODS: Determination of demographic characteristics, vital signs at admission, patient comorbidities and recorded discharge disposition in this population to construct a logistic regression estimating the odds of mortality, particular for those patients characterized as not being critically ill at admission. RESULTS: In total, 6,180 COVID-19+ patients were identified as of May 12, 2020. Most COVID-19+ patients (4,808, 77.8%) were admitted directly to a medical-surgical unit with no documented critical care or mechanical ventilation within 8 hours of admission. After adjusting for demographic characteristics, comorbidities, and vital signs at admission in this subgroup, the largest driver of the odds of mortality was patient age (OR, 1.07; 95% CI, 1.06-1.08; P < .001). Decreased oxygen saturation at admission was associated with increased odds of mortality (OR, 1.09; 95% CI, 1.06-1.12; P < .001) as was diabetes (OR, 1.57; 95% CI, 1.21-2.03; P < .001). CONCLUSIONS: The identification of factors observable at admission that are associated with mortality in COVID-19 patients who are initially admitted to non-critical care units may help care providers, hospital epidemiologists, and hospital safety experts better plan for the care of these patients.

Changes in hospitalized coronavirus disease 2019 (COVID-19) patient characteristics and resource use in a system of community hospitals in the United States.

Coronavirus disease 2019 (COVID-19) has migrated to regions that were initially spared, and it is likely that different populations are currently at risk for illness. Herein, we present our observations of the change in characteristics and resource use of COVID-19 patients over time in a national system of community hospitals to help inform those managing surge planning, operational management, and future policy decisions.

2019 John M. Eisenberg Patient Safety and Quality Awards: SPOTting Sepsis to Save Lives: A Nationwide Computer Algorithm for Early Detection of Sepsis: Innovation in Patient Safety and Quality at the National Level (Eisenberg Award).

BACKGROUND: In recognition of the potential of data to drive care and the need for early identification of patients with sepsis, HCA Healthcare developed an automated sepsis detection algorithm-SPOT (Sepsis Prediction and Optimization of Therapy). The algorithm was deployed at scale and served as a mechanism to reduce the time to detection and improve sepsis mortality in 173 hospitals across the United States. METHODS: The SPOT algorithm was designed as a rules-based detection of defined criteria that would interpret available electronic and basic laboratory data in near real time. Working from an organizational recognition of the need to construct a national clinical data warehouse to allow for the aggregation and analysis of data streams, HCA Healthcare designed and deployed SPOT and delivered the alert from the algorithm to the bedside to initiate existing clinical workflows for patients with sepsis. RESULTS: SPOT improved the timeliness of sepsis detection by providing alerts when signals of sepsis become available, triggering initiation of sepsis screens. This gave an advantage of about six hours over the legacy practice of sepsis screening at shift change. When deployed alongside existing sepsis improvement initiatives, SPOT was associated with an acceleration of improvement in mortality-particularly in the not-present-on-admission (NPOA) septic shock population, the patients at greatest risk for mortality. This population had seen little improvement with prior initiatives, but mortality improved 3.9 percentage points from 2018 to 2019. When accounting for seasonal variation, there was a decline in mortality rate following the deployment of SPOT, as compared to the year prior, of 9.9% for NPOA severe sepsis and 5.1% for NPOA septic shock. CONCLUSION: Development of the SPOT algorithm for the detection of sepsis from data available in the electronic health record resulted in more timely recognition, faster initiation of treatment, and improved survival for patients.

Reduced post-operative opioid use decreases length of stay and readmission rates in patients undergoing hip and knee joint arthroplasty.

BACKGROUND: While adequate pain relief is central to patient recovery and satisfaction, opioid use is associated with side effects, adverse drug events and opioid use disorder and therefore is under increased scrutiny. Enhanced surgical recovery protocols include multimodal pain management as a key process, but the impact of opioid dose as an independent variable has not been examined. METHODS: Retrospective analysis of 51,824 hip and knee arthroplasty encounters in a large healthcare system. RESULTS: Overall, patients receiving treatment with lower doses of opiates had shorter median length of stay (p < 0.001); this earlier discharge had no negative consequences on readmission rates. In particular, patients discharged on day 1 received a lower median morphine milligram equivalent (MME) per day than those who were not discharged (32.5 [IQR: 19.0-50.0] versus 45.0 [26.7-71.2], respectively, p < 0.001). The probability of discharge on day 1 was 41.2% and 19.6% for those patients on lower versus higher MME/day, respectively. Similarly, there was a reduction in odds of readmission of 15.2% (95% CI 5.8-23.6%) for patients on lower doses of MME/day. CONCLUSION: Lower MME/day following joint arthroplasty is linked to the probability of discharge on both days 1 and 2 post-surgery as well as reduced odds of readmission. These findings persisted even when adjusting for all other factors, including participation in the enhanced surgical recovery program, the use of a multi-modal analgesic regimen, the presence of complications, patient demographics, and other baseline characteristics. Efforts to reduce opioid use in the peri- and immediate post-operative period, regardless of the mechanism, demonstrated a significant effect on patient outcomes.

Driving stroke quality improvement at scale in EDs across a nationwide network of hospitals: strategies and interventions.

OBJECTIVES: Reducing the treatment time while increasing the proportion of eligible stroke patients who receive intravenous tissue plasminogen activator (tPA) has been a priority for many quality improvement efforts. Recent studies have primarily focused on identifying interventions that reduce door-to-needle (DTN) time, while comparatively little has been done to determine whether these interventions also improve tPA rates. METHODS: In order to investigate interventions related to process improvements, an electronic dashboard serving as a stroke performance tool was implemented to store and retrieve patient outcome data. These data were used to study the efficacy of interventions designed to facilitate triage of stroke patients in the ED, and determine the individual interventions associated with the most significant improvements in the fraction of patients receiving tPA and in reducing the DTN time. Stroke performance data from the dashboard collected over a 2-year period (2015-2017) from 89 US hospitals were analysed with respect to interventions implemented by individual facilities, as verified by a hospital survey. RESULTS: A statistically significant association was found between increases in the fraction of patients receiving tPA and reductions in DTN time over the study period. These improvements in outcomes were most strongly associated with process interventions that allocate stroke-specific physical and human resources in the ED, most notably a designated emergency room space for stroke, and with workflows that decrease the time to key checkpoints for determining a patient's eligibility for tPA. CONCLUSIONS: Data from the stroke performance tool was leveraged to identify the programmes and process interventions that lead to improved patient outcomes and allow EDs to better prioritise process interventions and resources.

Units of Distinction: Creating a Blueprint for Recognition of High-Performing Medical-Surgical Nursing Units.

BACKGROUND: Hospital medical-surgical (M/S) nursing units are responsible for up to 28 million encounters annually, yet receive little attention from professional organizations and national initiatives targeted to improve quality and performance. OBJECTIVE: We sought to develop a framework recognizing high-performing units within our large hospital system. METHODS: This was a retrospective data analysis of M/S units throughout a 168-hospital system. Measures represented patient experience, employee engagement, staff scheduling, nursing-sensitive patient outcomes, professional practices, and clinical process measures. RESULTS: Four hundred ninety units from 129 hospitals contributed information to test the framework. A manual scoring system identified the top 5% and recognized them as a "Unit of Distinction." Secondary analyses with machine learning provided validation of the proposed framework. CONCLUSIONS: Similar to external recognition programs, this framework and process provide a holistic evaluation useful for meaningful recognition and lay the groundwork for benchmarking in improvement efforts.

A Comprehensive Program to Reduce Rates of Hospital-Acquired Pressure Ulcers in a System of Community Hospitals.

OBJECTIVES: The prevention of hospital-acquired pressure ulcers (PrUs) has significant consequences for patient outcomes and the cost of care. Providers are challenged with evaluating available evidence and best practices, then implementing programs and motivating change in various facility environments. METHODS: In a large system of community hospitals, the Reducing Hospital Acquired-PrUs Program was developed to provide a toolkit of best practices, timely and appropriate data for focusing efforts, and continuous implementation support. Baseline data on PrU rates helped focus efforts on the most vulnerable patients and care situations. Facilities were empowered to use and adapt available resources to meet local needs and to share best practices for implementation across the system. Outcomes were measured by the rate of hospital-acquired PrUs, as gathered from patient discharge records. RESULTS: The rate of hospital-acquired stage III and IV PrUs decreased 66.3% between 2011 and 2013. Of the 149 participating facilities, 40 (27%) had zero hospital-acquired stage III and IV PrUs and 77 (52%) had a reduction in their PrU rate. Rates of all PrUs documented as present on admission did not change during this period. A comparison of different strategies used by the most successful facilities illustrated the necessity of facility-level flexibility and recognition of local workflows and patient demographics. CONCLUSIONS: Driven by the combination of a repository of evidence-based tools and best practices, readily available data on PrU rates, and local flexibility with processes, the Reducing Hospital Acquired-PrUs Program represents the successful operationalization of improvement in a wide variety of facilities.

Evaluating the Risk Factors for Hospital-Onset Clostridium difficile Infections in a Large Healthcare System.

In this multicenter retrospective cohort study of over 1 million patients at 150 US hospitals, proton pump inhibitors increased the odds of a patient having hospital-onset Clostridium difficile infection as did third and fourth generation cephalosporins, carbapenems, and piperacillin/tazobactam. These findings support appropriate prescribing of acid-suppression therapy and high-risk antibiotics.

Implementing an electronic hand hygiene monitoring system: Lessons learned from community hospitals.

BACKGROUND: Measuring and providing feedback about hand hygiene (HH) compliance is a complicated process. Electronic HH monitoring systems have been proposed as a possible solution; however, there is little information available about how to successfully implement and maintain these systems for maximum benefit in community hospitals. METHODS: An electronic HH monitoring system was implemented in 3 community hospitals by teams at each facility with support from the system vendor. Compliance rates were measured by the electronic monitoring system. The implementation challenges, solutions, and drivers of success were monitored within each facility. RESULTS: The electronic HH monitoring systems tracked on average more than 220,000 compliant HH events per facility per month, with an average monthly compliance rate >85%. The sharing of best practices between facilities was valuable in addressing challenges encountered during implementation and maintaining a high rate of use. DISCUSSION: Drivers of success included a collaborative environment, leadership commitment, using data to drive improvement, consistent and constant messaging, staff empowerment, and patient involvement. CONCLUSIONS: Realizing the full benefit of investments in electronic HH monitoring systems requires careful consideration of implementation strategies, planning for ongoing support and maintenance, and presenting data in a meaningful way to empower and inspire staff.

Data-driven process and operational improvement in the emergency department: the ED Dashboard and Reporting Application.

Emergency departments (EDs) in the United States are expected to provide consistent, high-quality care to patients. Unfortunately, EDs are encumbered by problems associated with the demand for services and the limitations of current resources, such as overcrowding, long wait times, and operational inefficiencies. While increasing the effectiveness and efficiency of emergency care would improve both access and quality of patient care, coordinated improvement efforts have been hindered by a lack of timely access to data. The ED Dashboard and Reporting Application was developed to support data-driven process improvement projects. It incorporated standard definitions of metrics, a data repository, and near real-time analysis capabilities. This helped acute care hospitals in a large healthcare system evaluate and target individual improvement projects in accordance with corporate goals. Subsequently, there was a decrease in "arrival to greet" time--the time from patient arrival to physician contact--from an average of 51 minutes in 2007 to the goal level of less than 35 minutes by 2010. The ED Dashboard and Reporting Application has also contributed to data-driven improvements in length of stay and other measures of ED efficiency and care quality. Between January 2007 and December 2010, overall length of stay decreased 10.5 percent while annual visit volume increased 13.6 percent. Thus, investing in the development and implementation of a system for ED data capture, storage, and analysis has supported operational management decisions, gains in ED efficiency, and ultimately improvements in patient care.

ApoE isoform-dependent changes in hippocampal synaptic function.

The lipoprotein receptor system in the hippocampus is intimately involved in the modulation of synaptic transmission and plasticity. The association of specific apoE isoform expression with human neurodegenerative disorders has focused attention on the role of these apoE isoforms in lipoprotein receptor-dependent synaptic modulation. In the present study, we used the apoE2, apoE3 and apoE4 targeted replacement (TR) mice along with recombinant human apoE isoforms to determine the role of apoE isoforms in hippocampus area CA1 synaptic function. While synaptic transmission is unaffected by apoE isoform, long-term potentiation (LTP) is significantly enhanced in apoE4 TR mice versus apoE2 TR mice. ApoE isoform-dependent differences in LTP induction require NMDA-receptor function, and apoE isoform expression alters activation of both ERK and JNK signal transduction. Acute application of specific apoE isoforms also alters LTP induction while decreasing NMDA-receptor mediated field potentials. Furthermore, acute apoE isoform application does not have the same effects on ERK and JNK activation. These findings demonstrate specific, isoform-dependent effects of human apoE isoforms on adult hippocampus synaptic plasticity and highlight mechanistic differences between chronic apoE isoform expression and acute apoE isoform exposure.