Gelareh Z. Gabayan

Sensitivity of Noncontrast Cranial Computed Tomography for the Emergency Department Diagnosis of Subarachnoid Hemorrhage

STUDY OBJECTIVE Emergency physicians use noncontrast cranial computed tomographic (CT) imaging of headache patients to identify subarachnoid hemorrhage caused by aneurysms or arteriovenous malformations. Given sufficiently high sensitivity, CT imaging could be used as a definitive diagnostic study in these patients. The purpose of this study is to determine the sensitivity of noncontrast cranial CT in detecting all spontaneous subarachnoid hemorrhages and those caused by aneurysm or arteriovenous malformation. METHODS This was a retrospective review performed at an urban tertiary academic emergency department (ED). Using a combination of noncontrast cranial CT radiology coding, lumbar puncture results, International Classification of Diseases, Ninth Revision discharge diagnosis, and medical record review, we identified all patients who presented to a tertiary care academic ED from August 1, 2001, to December 31, 2004, with spontaneous subarachnoid hemorrhage. We determined whether patients were diagnosed by cranial CT or lumbar puncture, the presence of headache and level of consciousness at ED presentation, and whether or not they had an aneurysm or arteriovenous malformation. RESULTS We identified 149 patients who were diagnosed with spontaneous subarachnoid hemorrhage during the study period. Noncontrast cranial CT scan diagnosed 139 patients, and 10 were diagnosed with lumbar puncture. This yielded an overall CT scan sensitivity of 93% (95% confidence interval [CI] 88% to 97%). Of the 149 with subarachnoid hemorrhage, 117 (79%) had aneurysm or arteriovenous malformation; cranial CT scan demonstrated subarachnoid hemorrhage in 110 of the 117, for a sensitivity of 94% (95% CI 88% to 98%). For the 67 patients presenting with headache and normal mental status who had a subarachnoid hemorrhage and vascular lesions (either aneurysm or arteriovenous malformation), the sensitivity of cranial CT scan was 91% (95% CI 82% to 97%). CONCLUSION Noncontrast CT imaging exhibits inadequate sensitivity to serve as a sole diagnostic modality in detecting spontaneous subarachnoid hemorrhage caused by aneurysm or arteriovenous malformation.

Predictors of 30-Day Serious Events in Older Patients With Syncope

STUDY OBJECTIVE We identify predictors of 30-day serious events after syncope in older adults. METHODS We reviewed the medical records of older adults (age > or =60 years) who presented with syncope or near syncope to one of 3 emergency departments (EDs) between 2002 and 2005. Our primary outcome was occurrence of a predefined serious event within 30 days after ED evaluation. We used multivariable logistic regression to identify predictors of 30-day serious events. RESULTS Of 3,727 potentially eligible patients, 2,871 (77%) met all eligibility criteria. We excluded an additional 287 patients who received a diagnosis of a serious clinical condition while in the ED. In the final study cohort (n=2,584), we identified 173 (7%) patients who experienced a 30-day serious event. High-risk predictors included age greater than 90 years, male sex, history of an arrhythmia, triage systolic blood pressure greater than 160 mm Hg, abnormal ECG result, and abnormal troponin I level. A low-risk predictor was a complaint of near syncope rather than syncope. A risk score, generated by summing high-risk predictors and subtracting the low-risk predictor, can stratify patients into low- (event rate 2.5%; 95% confidence interval [CI] 1.4% to 3.6%), intermediate- (event rate 6.3%; 95% CI 5.1% to 7.5%), and high-risk (event rate 20%; 95% CI 15% to 25%) groups. CONCLUSION We identified predictors of 30-day serious events after syncope in adults aged 60 years and greater. A simple score was able to stratify these patients into distinct risk groups and, if externally validated, might have the potential to aid ED decisionmaking.

Factors Associated With Short-Term Bounce-Back Admissions After Emergency Department Discharge

STUDY OBJECTIVE Hospitalizations that occur shortly after emergency department (ED) discharge may reveal opportunities to improve ED or follow-up care. There currently is limited, population-level information about such events. We identify hospital- and visit-level predictors of bounce-back admissions, defined as 7-day unscheduled hospital admissions after ED discharge. METHODS Using the California Office of Statewide Health Planning and Development files, we conducted a retrospective cohort analysis of adult (aged >18 years) ED visits resulting in discharge in 2007. Candidate predictors included index hospital structural characteristics such as ownership, teaching affiliation, trauma status, and index ED size, along with index visit patient characteristics of demographic information, day of service, against medical advice or eloped disposition, insurance, and ED primary discharge diagnosis. We fit a multivariable, hierarchic logistic regression to account for clustering of ED visits by hospitals. RESULTS The study cohort contained a total of 5,035,833 visits to 288 facilities in 2007. Bounce-back admission within 7 days occurred in 130,526 (2.6%) visits and was associated with Medicaid (odds ratio [OR] 1.42; 95% confidence interval [CI] 1.40 to 1.45) or Medicare insurance (OR 1.53; 95% CI 1.50 to 1.55) and a disposition of leaving against medical advice or before the evaluation was complete (OR 1.90; 95% CI 1.89 to 2.0). The 3 most common age-adjusted index ED discharge diagnoses associated with a bounce-back admission were chronic renal disease, not end stage (OR 3.3; 95% CI 2.8 to 3.8), end-stage renal disease (OR 2.9; 95% CI 2.4 to 3.6), and congestive heart failure (OR 2.5; 95% CI 2.3 to 2.6). Hospital characteristics associated with a higher bounce-back admission rate were for-profit status (OR 1.2; 95% CI 1.1 to 1.3) and teaching affiliation (OR 1.2; 95% CI 1.0 to 1.3). CONCLUSION We found 2.6% of discharged patients from California EDs to have a bounce-back admission within 7 days. We identified vulnerable populations, such as the very old and the use of Medicaid insurance, and chronic or end-stage renal disease as being especially at risk. Our findings suggest that quality improvement efforts focus on high-risk individuals and that the disposition plan of patients consider vulnerable populations.

Predictors of Short-Term (Seven-Day) Cardiac Outcomes After Emergency Department Visit for Syncope

Syncope is a common reason for emergency department (ED) visits, and patients are often admitted to exclude syncope of cardiovascular origin. Population-based data on patterns and predictors of cardiac outcomes may improve decision-making. Our objective was to identify patterns and predictors of short-term cardiac outcomes in ED patients with syncope. Administrative data from an integrated health system of 11 Southern California EDs were used to identify cardiac outcomes after ED presentation for syncope from January 1, 2002, to December 31, 2005. Syncope and cause of death were identified by codes from the International Classification of Disease, Ninth Revision. Cardiac outcomes included cardiac death and hospitalization or procedure consistent with ischemic heart disease, valvular disease, or arrhythmia. Predictors of cardiac outcomes were identified through multivariate logistic regression. There were 35,330 adult subjects who accounted for 39,943 ED visits for syncope. Risk of cardiac outcome sharply decreased following the 7 days after syncope. A 7-day cardiac outcome occurred in 893 cases (3%). Positive predictors of 7-day cardiac outcomes included age > or =60 years, male gender, congestive heart failure, ischemic heart disease, cardiac arrhythmia, and valvular heart disease. Negative predictors included dementia, pacemaker, coronary revascularization, and cerebrovascular disease. There was an age-dependent relation between 7-day cardiac outcomes and arrhythmia and valvular disease, with younger patients (<60 years of age) having greater risk of an event compared to their same-age counterparts. In conclusion, ED decision-making should focus on risk of cardiac event in the first 7 days after syncope and special attention should be given to younger patients with cardiac co-morbidities.

Emergency department crowding predicts admission length-of-stay but not mortality in a large health system

Background:Emergency department (ED) crowding has been identified as a major threat to public health. Objectives:We assessed patient transit times and ED system crowding measures based on their associations with outcomes. Research Design:Retrospective cohort study. Subjects:We accessed electronic health record data on 136,740 adults with a visit to any of 13 health system EDs from January 2008 to December 2010. Measures:Patient transit times (waiting, evaluation and treatment, boarding) and ED system crowding [nonindex patient length-of-stay (LOS) and boarding, bed occupancy] were determined. Outcomes included individual inpatient mortality and admission LOS. Covariates included demographic characteristics, past comorbidities, severity of illness, arrival time, and admission diagnoses. Results:No patient transit time or ED system crowding measure predicted increased mortality after control for patient characteristics. Index patient boarding time and lower bed occupancy were associated with admission LOS (based on nonoverlapping 95% CI vs. the median value). As boarding time increased from none to 14 hours, admission LOS increased an additional 6 hours. As mean occupancy decreased below the median (80% occupancy), admission LOS decreased as much as 9 hours. Conclusions:Measures indicating crowded ED conditions were not predictive of mortality after case-mix adjustment. The first half-day of boarding added to admission LOS rather than substituted for it. Our findings support the use of boarding time as a measure of ED crowding based on robust prediction of admission LOS. Interpretation of measures based on other patient ED transit times may be limited to the timeliness of care.

Patterns and Preexisting Risk Factors of 30-Day Mortality After a Primary Discharge Diagnosis of Syncope or Near Syncope

OBJECTIVES The risk of short-term mortality after an emergency department (ED) visit for syncope is poorly understood, resulting in prognostic uncertainty and frequent hospital admission. The authors determined patterns and risk factors for short-term mortality after a diagnosis of syncope or near syncope to aid in medical decision-making. METHODS A retrospective cohort study was performed of adult members of Kaiser Permanente Southern California seen at 11 EDs from 2002 to 2006 with a primary discharge diagnosis of syncope or near syncope (International Classification of Diseases, Ninth Revision [ICD-9] 780.2). The outcome was 30-day mortality. Proportional hazards time-to-event regression models were used to identify risk factors. RESULTS There were 22,189 participants with 23,951 ED visits, resulting in 307 deaths by 30 days. A relatively lower risk of death was reached within 2 weeks for ages 18 to 59 years, but not until 3 months or more for ages 60 and older. Preexisting comorbidities associated with increased mortality included heart failure (hazard ratio [HR] = 14.3 in ages 18 to 59 years, HR = 3.09 in ages 60 to 79 years, HR = 2.34 in ages 80 years plus; all p < 0.001), diabetes (HR = 1.49, p = 0.002), seizure (HR = 1.65, p = 0.016), and dementia (HR = 1.41, p = 0.034). If the index visit followed one or more visits for syncope in the previous 30 days, it was associated with increased mortality (HR = 1.86, p = 0.024). Absolute risk of death at 30 days was under 0.2% in those under 60 years without heart failure and more than 2.5% across all ages in those with heart failure. CONCLUSIONS The low risk of death after an ED visit for syncope or near syncope in patients younger than 60 years old without heart failure may be helpful when deciding who to admit for inpatient evaluation. The presence of one or more comorbidities that predict death and a prior visit for syncope should be considered in clinical decisions and risk stratification tools for patients with syncope. Close clinical follow-up seems advisable in patients 60 years and older due to a prolonged risk of death.

Predictors of Admission After Emergency Department Discharge in Older Adults

To identify predictors of hospital inpatient admission of older Medicare beneficiaries after discharge from the emergency department (ED).

Qualitative Factors in Patients Who Die Shortly After Emergency Department Discharge

OBJECTIVES Early death after emergency department (ED) discharge may signal opportunities to improve care. Prior studies are limited by incomplete mortality ascertainment and lack of clinically important information in administrative data. The goal in this hypothesis-generating study was to identify patient and process of care themes that may provide possible explanations for early postdischarge mortality. METHODS This was a qualitative analysis of medical records of adult patients who visited the ED of any of six hospitals in an integrated health system (Kaiser Permanente Southern California [KPSC]) and died within 7 days of discharge in 2007 and 2008. Nonmembers, visits to non-health plan hospitals, patients receiving or referred to hospice care, and patients with do not attempt resuscitation or do not intubate orders (DNAR/DNI) were excluded. Under the guidance of two qualitative research scientists, a team of three emergency physicians used grounded theory techniques to identify patient clinical presentations and processes of care that serve as potential explanations for poor outcome after discharge. RESULTS The source population consisted of a total of 290,092 members with 446,120 discharges from six KPSC EDs in 2007 and 2008. A total of 203 deaths occurred within 7 days of ED discharge (0.05%). Sixty-one randomly chosen cases were reviewed. Patient-level themes that emerged included an unexplained persistent acute change in mental status, recent fall, abnormal vital signs, ill-appearing presentation, malfunctioning indwelling device, and presenting symptoms remaining at discharge. Process-of-care factors included a discrepancy in history of present illness, incomplete physical examination, and change of discharge plan by a third party, such as a consulting or admitting physician. CONCLUSIONS In this hypothesis-generating study, qualitative research techniques were used to identify clinical and process-of-care factors in patients who died within days after discharge from an ED. These potential predictors will be formally tested in a future quantitative study.

Emergency Department Crowding and Outcomes After Emergency Department Discharge

STUDY OBJECTIVE We assess whether a panel of emergency department (ED) crowding measures, including 2 reported by the Centers for Medicare & Medicaid Services (CMS), is associated with inpatient admission and death within 7 days of ED discharge. METHODS We conducted a retrospective cohort study of ED discharges, using data from an integrated health system for 2008 to 2010. We assessed patient transit-level (n=3) and ED system-level (n=6) measures of crowding, using multivariable logistic regression models. The outcome measures were inpatient admission or death within 7 days of ED discharge. We defined a clinically important association by assessing the relative risk ratio and 95% confidence interval (CI) difference and also compared risks at the 99th percentile and median value of each measure. RESULTS The study cohort contained a total of 625,096 visits to 12 EDs. There were 16,957 (2.7%) admissions and 328 (0.05%) deaths within 7 days. Only 2 measures, both of which were patient transit measures, were associated with the outcome. Compared with a median evaluation time of 2.2 hours, the evaluation time of 10.8 hours (99th percentile) was associated with a relative risk of 3.9 (95% CI 3.7 to 4.1) of an admission. Compared with a median ED length of stay (a CMS measure) of 2.8 hours, the 99th percentile ED length of stay of 11.6 hours was associated with a relative risk of 3.5 (95% CI 3.3 to 3.7) of admission. No system measure of ED crowding was associated with outcomes. CONCLUSION Our findings suggest that ED length of stay is a proxy for unmeasured differences in case mix and challenge the validity of the CMS metric as a safety measure for discharged patients.

Is emergency department crowding associated with increased “bounceback” admissions?

Objective:Emergency department (ED) crowding is linked with poor quality of care and worse outcomes, including higher mortality. With the growing emphasis on hospital performance measures, there is additional concern whether inadequate care during crowded periods increases a patient’s likelihood of subsequent inpatient admission. We sought to determine if ED crowding during the index visit was associated with these “bounceback” admissions. Methods:We used comprehensive, nonpublic, statewide ED and inpatient discharge data from the California Office of Statewide Health Planning and Development from 2007 to identify index outpatient ED visits and bounceback admissions within 7 days. We further used ambulance diversion data collected from California local emergency medical services agencies to identify crowded days using intrahospital daily diversion hour quartiles. Using a hierarchical logistic regression model, we then determined if patients visiting on crowded days were more likely to have a subsequent bounceback admission. Results:We analyzed 3,368,527 index visits across 202 hospitals, of which 596,471 (17.7%) observations were on crowded days. We found no association between ED crowding and bounceback admissions. This lack of relationship persisted in both a discrete (high/low) model (OR, 1.01; 95% CI, 0.99, 1.02) and a secondary model using ambulance diversion hours as a continuous predictor (OR, 1.00; 95% CI, 1.00, 1.00). Conclusions:Crowding as measured by ambulance diversion does not have an association with hospitalization within 7 days of an ED visit discharge. Therefore, bounceback admission may be a poor measure of delayed or worsened quality of care due to crowding.