External Validation of the San Francisco Syncope Rule in the Canadian Setting

An efficient approach to the inpatient Syncope Workup

OBJECTIVE

This review aims to provide hospitalists with a streamlined understanding of the evaluation of syncope, a commonly encountered complaint in hospital medicine.

METHODS

Authors conducted a literature review using the keyword 'syncope' to compile current evidence and recommendations regarding the categorization, risk stratification, and diagnostic evaluation of syncope.

RESULTS

The review outlines the categorization of syncope into cardiac, neurally-mediated, and orthostatic types, detailing the clinical features, etiologies, and differential diagnoses of each. It provides a structured framework for history-taking, physical examination, orthostatic vital sign assessment, and risk stratification to guide clinicians in efficiently identifying high-risk patients requiring urgent intervention. Diagnostic modalities including electrocardiography, echocardiography, and point-of-care ultrasound are discussed, along with their respective indications and limitations.

CONCLUSION

By embracing standardized approaches and evidence-based practices outlined in this review, hospitalists can optimize resource utilization, streamline patient care, and improve outcomes in patients presenting with syncope.

Comparison of syncope risk scores in predicting the prognosis of patients presenting to the emergency department with syncope

BACKGROUND

Various scores have been derived for the assessment of syncope patients in the emergency department (ED).

AIM

We aimed to compare the effectiveness of Canadian Syncope Risk Scores (CSRS), San Francisco Syncope Rules (SFSR), and Osservatorio Epidemiologico sulla Sincope nel Lazio (OESIL) risk scores in predicting the risk of major adverse cardiac events (MACE) and mortality among syncope patients within 30 days of the initial ED visit.

METHODS

We performed a prospective, observational case series study of adults (≥ 18 years) with unexplained syncope/near-syncope who presented to ED. Demographic characteristics of the patients and clinical and laboratory data were recorded in the standard data collection form of the study. Our primary outcome was a 30-day mortality.

RESULTS

A total of 421 patients (mean age 50.9 ± 20.8, 51.5% male) were enrolled. The rate of MACE development in the 30-day follow-up of the patients was 12.8% (n = 54). While 20.2% (n = 85) of the patients were hospitalized, two of the patients died in the emergency room and the 30-day mortality was 5.5% (n = 23). CSRS was found to have the highest predictive power of mortality (AUC: 0.869, 95% CI 0.799-0.939, p < 0.001). If the cut-off value of CSRS was 0.5, the sensitivity was found to be 82.6% and the specificity was 81.9%. Also CSRS (OR: 1.402, 95% CI: 1.053-1.867, p = 0.021) was found to be an independent predictor of the 30-day mortality.

CONCLUSION

The CSRS may be used as a safety risk score for a 30-day risk of MACE and mortality after discharge from the emergency department.

Risk stratification tools for patients with syncope in emergency medical services and emergency departments: a scoping review

BACKGROUND

Patients with a syncope constitute a challenge for risk stratification in (prehospital) emergency care. Professionals in EMS and ED need to differentiate the high-risk from the low-risk syncope patient, with limited time and resources. Clinical decision rules (CDRs) are designed to support professionals in risk stratification and clinical decision-making. Current CDRs seem unable to meet the standards to be used in the chain of emergency care. However, the need for a structured approach for syncope patients remains. We aimed to generate a broad overview of the available risk stratification tools and identify key elements, scoring systems and measurement properties of these tools.

METHODS

We performed a scoping review with a literature search in MEDLINE, CINAHL, Pubmed, Embase, Cochrane and Web of Science from January 2010 to May 2022. Study selection was done by two researchers independently and was supervised by a third researcher. Data extraction was performed through a data extraction form, and data were summarised through descriptive synthesis. A quality assessment of included studies was performed using a generic quality assessment tool for quantitative research and the AMSTAR-2 for systematic reviews.

RESULTS

The literature search identified 5385 unique studies; 38 were included in the review. We discovered 19 risk stratification tools, one of which was established in EMS patient care. One-third of risk stratification tools have been validated. Two main approaches for the application of the tools were identified. Elements of the tools were categorised in history taking, physical examination, electrocardiogram, additional examinations and other variables. Evaluation of measurement properties showed that negative and positive predictive value was used in half of the studies to assess the accuracy of tools.

CONCLUSION

A total of 19 risk stratification tools for syncope patients were identified. They were primarily established in ED patient care; most are not validated properly. Key elements in the risk stratification related to a potential cardiac problem as cause for the syncope. These insights provide directions for the key elements of a risk stratification tool and for a more advanced process to validate risk stratification tools.

International Validation of the Canadian Syncope Risk Score : A Cohort Study

BACKGROUND

The Canadian Syncope Risk Score (CSRS) was developed to predict 30-day serious outcomes not evident during emergency department (ED) evaluation.

OBJECTIVE

To externally validate the CSRS and compare it with another validated score, the Osservatorio Epidemiologico della Sincope nel Lazio (OESIL) score.

DESIGN

Prospective cohort study.

SETTING

Large, international, multicenter study recruiting patients in EDs in 8 countries on 3 continents.

PARTICIPANTS

Patients with syncope aged 40 years or older presenting to the ED within 12 hours of syncope.

MEASUREMENTS

Composite outcome of serious clinical plus procedural events (primary outcome) and the primary composite outcome excluding procedural interventions (secondary outcome).

RESULTS

Among 2283 patients with a mean age of 68 years, the primary composite outcome occurred in 7.2%, and the composite outcome excluding procedural interventions occurred in 3.1% at 30 days. Prognostic performance of the CSRS was good for both 30-day composite outcomes and better compared with the OESIL score (area under the receiver-operating characteristic curve [AUC], 0.85 [95% CI, 0.83 to 0.88] vs. 0.74 [CI, 0.71 to 0.78] and 0.80 [CI, 0.75 to 0.84] vs. 0.69 [CI, 0.64 to 0.75], respectively). Safety of triage, as measured by the frequency of the primary composite outcome in the low-risk group, was higher using the CSRS (19 of 1388 [0.6%]) versus the OESIL score (17 of 1104 [1.5%]). A simplified model including only the clinician classification of syncope (cardiac syncope, vasovagal syncope, or other) variable at ED discharge-a component of the CSRS-achieved similar discrimination as the CSRS (AUC, 0.83 [CI, 0.80 to 0.87] for the primary composite outcome).

LIMITATION

Unable to disentangle the influence of other CSRS components on clinician classification of syncope at ED discharge.

CONCLUSION

This international external validation of the CSRS showed good performance in identifying patients at low risk for serious outcomes outside of Canada and superior performance compared with the OESIL score. However, clinician classification of syncope at ED discharge seems to explain much of the performance of the CSRS in this study. The clinical utility of the CSRS remains uncertain.

PRIMARY FUNDING SOURCE

Swiss National Science Foundation & Swiss Heart Foundation.

Syncope and the aging patient: Navigating the challenges

Syncope in the elderly patient is a common presentation and the most common causes are usually non-cardiac. Older adults however are more challenging dilemmas as their presentation is complicated by co-morbidities, mainly cardiovascular and neurodegenerative disorders. Frailty and cognitive impairment add to the ambiguity of the presentation, and polypharmacy is often a major modifiable contributing factor. Vasovagal syncope is a common presentation throughout life even as we age. It has a favorable prognosis and conservative management usually suffices. Vasovagal syncope in this population may be misdiagnosed as accidental falls and is frequently associated with injury, as is carotid sinus syndrome. The initial approach to these patients entails a detailed history and physical examination including a comprehensive medication history, orthostatic vital signs, and a 12-lead electrocardiogram. Further cardiac and neuroimaging rarely helps, unless directed by specific clinical findings. Head-up tilt testing and carotid sinus massage retain their diagnostic accuracy and safety in the elderly, and implantable loop recorders provide important information in many elderly patients with unexplained falls and syncope. The starting point in management of this population with non-cardiac syncope is attempting to withdraw unnecessary vasoactive and psychotropic medications. Non-pharmacologic and pharmacologic therapy for syncope in the elderly has limited efficacy and safety concerns. In selected patients, pacemaker therapy might offer symptomatic relief despite lack of efficacy when vasodepression is prominent. An approach focused on primary care with targeted specialist referral seems a safe and effective strategy.

Personalised risk prediction following emergency department assessment for syncope

BACKGROUND

Published risk tools do not provide possible management options for syncope in the emergency department (ED). Using the 30-day observed risk estimates based on the Canadian Syncope Risk Score (CSRS), we developed personalised risk prediction to guide management decisions.

METHODS

We pooled previously reported data from two large cohort studies, the CSRS derivation and validation cohorts, that prospectively enrolled adults (≥16 years) with syncope at 11 Canadian EDs between 2010 and 2018. Using this larger cohort, we calculated the CSRS calibration and discrimination, and determined with greater precision than in previous studies the 30-day risk of adjudicated serious outcomes not identified during the index ED evaluation depending on the CSRS and the risk category. Based on these findings, we developed an on-line calculator and pictorial decision aids.

RESULTS

8233 patients were included of whom 295 (3.6%, 95% CI 3.2% to 4.0%) experienced 30-day serious outcomes. The calibration slope was 1.0, and the area under the curve was 0.88 (95% CI 0.87 to 0.91). The observed risk increased from 0.3% (95% CI 0.2% to 0.5%) in the very-low-risk group (CSRS -3 to -2) to 42.7% (95% CI 35.0% to 50.7%), in the very-high-risk (CSRS≥+6) group (Cochrane-Armitage trend test p<0.001). Among the very-low and low-risk patients (score -3 to 0), ≤1.0% had any serious outcome, there was one death due to sepsis and none suffered a ventricular arrhythmia. Among the medium-risk patients (score +1 to+3), 7.8% had serious outcomes, with <1% death, and a serious outcome was present in >20% of high/very-high-risk patients (score +4 to+11) including 4%-6% deaths. The online calculator and the pictorial aids can be found at: https://teamvenk.com/csrs CONCLUSIONS: 30-day observed risk estimates from a large cohort of patients can be obtained for management decision-making. Our work suggests very-low-risk and low-risk patients may be discharged, discussion with patients regarding investigations and disposition are needed for medium-risk patients, and high-risk patients should be hospitalised. The online calculator, accompanied by pictorial decision aids for the CSRS, may assist in discussion with patients.

External validation of the Canadian Syncope Risk Score for patients presenting with undifferentiated syncope to the emergency department

OBJECTIVE

To validate the accuracy and safety of the Canadian Syncope Risk Score (CSRS) for patients presenting with syncope.

METHODS

Single centre prospective observational study in Brisbane, Australia. Adults presenting to the ED with syncope within the last 24 h were recruited after applying exclusion criteria. Study was conducted over 1 year, from March 2018 to March 2019. Thirty-day serious adverse events (SAE) were reported based on the original derivation study and standardised outcome reporting for syncope. Individual patient CSRS was calculated and correlated with 30-day SAE and disposition status from ED.

RESULTS

Two hundred and eighty-three patients were recruited to the study. Average age was 55.6 years (SD 22.7 years), 37.1% being male with a 39.9% admission rate. Thirty-day SAE occurred in seven patients (2.5%) and no recorded deaths. The CSRS performed with a sensitivity of 71.4% (95% confidence interval [CI] 30.3-94.9%), specificity 72.8% (95% CI 67.1-77.9%) for a threshold score of 1 or higher.

CONCLUSION

Syncope patients in our study were predominantly very low to low risk (72%). The prevalence of 30-day SAE was low, majority occurring following hospital discharge. Sensitivity estimates for CSRS was lower than the derivation study but lacked robustness with wide CIs because of a small sample size and number of events observed. However, the CSRS did not miss any clinically relevant outcomes in low risk patients making it potentially useful in aiding their disposition. Larger validation studies in Australia are encouraged to further test the diagnostic accuracy of the CSRS.

A Rational Evaluation of the Syncope Patient: Optimizing the Emergency Department Visit

Syncope accounts for up to 2% of emergency department visits and results in the hospitalization of 12–86% of patients. There is often a low diagnostic yield, with up to 50% of hospitalized patients being discharged with no clear diagnosis. We will outline a structured approach to the syncope patient in the emergency department, highlighting the evidence supporting the role of clinical judgement and the initial electrocardiogram (ECG) in making the preliminary diagnosis and in safely identifying the patients at low risk of short- and long-term adverse events or admitting the patient if likely to benefit from urgent intervention. Clinical decision tools and additional testing may aid in further stratifying patients and may guide disposition. While hospital admission does not seem to offer additional mortality benefit, the efficient utilization of outpatient testing may provide similar diagnostic yield, preventing unnecessary hospitalizations.

Multivariable risk scores for predicting short-term outcomes for emergency department patients with unexplained syncope: A systematic review

OBJECTIVES

Emergency department (ED) patients with unexplained syncope are at risk of experiencing an adverse event within 30 days. Our objective was to systematically review the accuracy of multivariate risk stratification scores for identifying adult syncope patients at high and low risk of an adverse event over the next 30 days.

METHODS

We conducted a systematic review of electronic databases (MEDLINE, Cochrane, Embase, and CINAHL) from database creation until May 2020. We sought studies evaluating prediction scores of adults presenting to an ED with syncope. We included studies that followed patients for up to 30 days to identify adverse events such as death, myocardial infarction, stroke, or cardiac surgery. We only included studies with a blinded comparison between baseline clinical features and adverse events. We calculated likelihood ratios and confidence intervals (CIs).

RESULTS

We screened 13,788 abstracts. We included 17 studies evaluating nine risk stratification scores on 24,234 patient visits, where 7.5% (95% CI = 5.3% to 10%) experienced an adverse event. A Canadian Syncope Risk Score (CSRS) of 4 or more was associated with a high likelihood of an adverse event (LR_score≥4  = 11, 95% CI = 8.9 to 14). A CSRS of 0 or less (LR_score≤0  = 0.10, 95% CI = 0.07 to 0.20) was associated with a low likelihood of an adverse event. Other risk scores were not validated on an independent sample, had low positive likelihood ratios for identifying patients at high risk, or had high negative likelihood ratios for identifying patients at low risk.

CONCLUSION

Many risk stratification scores are not validated or not sufficiently accurate for clinical use. The CSRS is an accurate validated prediction score for ED patients with unexplained syncope. Its impact on clinical decision making, admission rates, cost, or outcomes of care is not known.

Association Between US Physician Malpractice Claims Rates and Hospital Admission Rates Among Patients With Lower-Risk Syncope

IMPORTANCE

The US Government Accountability Office has changed its estimate of the annual costs of defensive medicine, largely because it has been difficult to objectively measure its impact. Evaluating the association of malpractice claims rates with hospital admission rates and the costs of admitting patients with low-risk conditions would help to document the impact of defensive medicine. Although syncope is a concerning symptom, most patients with syncope have a low risk of adverse outcomes. However, many low-risk patients are still admitted to the hospital, with associated costs of more than $2.5 billion per year in the US.

OBJECTIVE

To assess whether hospital admission rates after emergency department visits among patients with lower-risk syncope are associated with state-level variations in malpractice claims rates.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study of emergency department visits among patients with lower-risk syncope used deidentified data from the Clinformatics Data Mart database (Optum). Lower-risk syncope visits were defined as those with a primary diagnosis of syncope and collapse based on International Classification of Diseases, Ninth Revision, Clinical Modification code 780.2 or International Classification of Diseases, Tenth Revision, Clinical Modification code R55 that did not include another major diagnostic code for a condition requiring hospital admission (such as heart disease, cancer, or medical shock) or an inpatient hospital stay of more than 3 days. These data were linked to publicly available data from the National Practitioner Data Bank pertaining to physician malpractice claims between January 1, 2008, and December 31, 2017. The 2 data sets were linked at the state-year level. Data were analyzed from October 2, 2019, to September 12, 2020.

MAIN OUTCOMES AND MEASURES

The association between the rate of hospital admission after emergency department visits among patients with lower-risk syncope and the rate of physician malpractice claims was assessed at the state-year level using a state-level fixed-effects model. Standardized costs obtained from the Clinformatics Data Mart database were adjusted for inflation and expressed in 2017 US dollars using the Consumer Price Index.

RESULTS

Among 40 482 813 emergency department visits between 2008 and 2017, 519 724 visits (1.3%) were associated with syncope. Of those, 234 750 visits (45.2%) met the criteria for lower-risk syncope. The mean (SD) age of patients in the lower-risk cohort was 71.8 (13.5) years; 141 050 patients (60.1%) were female, and 44 115 patients (18.8%) were admitted to the hospital, representing an extra cost of $6542 per admission. The mean rate of physician malpractice claims varied from 0.27 claims per 100 000 people to 8.63 claims per 100 000 people across states and across years within states. A state-level fixed-effects regression model indicated that, for every 1 in 100 000-person increase in the physician malpractice claims rate, there was an absolute increase of 6.70% (95% CI, 4.65%-8.75%) or a relative increase of 35.6% in the hospital admission rate, which represented an additional $102 million in costs associated with this lower-risk cohort.

CONCLUSIONS AND RELEVANCE

In this study, increases in physician malpractice claims rates were associated with increases in hospital admission rates and substantial health care costs for patients with lower-risk syncope, and these increases are likely associated with the practice of defensive medicine.

Risk Stratification of Older Adults Who Present to the Emergency Department With Syncope: The FAINT Score

STUDY OBJECTIVE

Older adults with syncope are commonly treated in the emergency department (ED). We seek to derive a novel risk-stratification tool to predict 30-day serious cardiac outcomes.

METHODS

We performed a prospective, observational study of older adults (≥60 years) with unexplained syncope or near syncope who presented to 11 EDs in the United States. Patients with a serious diagnosis identified in the ED were excluded. We collected clinical and laboratory data on all patients. Our primary outcome was 30-day all-cause mortality or serious cardiac outcome.

RESULTS

We enrolled 3,177 older adults with unexplained syncope or near syncope between April 2013 and September 2016. Mean age was 73 years (SD 9.0 years). The incidence of the primary outcome was 5.7% (95% confidence interval [CI] 4.9% to 6.5%). Using Bayesian logistic regression, we derived the FAINT score: history of heart failure, history of cardiac arrhythmia, initial abnormal ECG result, elevated pro B-type natriuretic peptide, and elevated high-sensitivity troponin T. A FAINT score of 0 versus greater than or equal to 1 had sensitivity of 96.7% (95% CI 92.9% to 98.8%) and specificity 22.2% (95% CI 20.7% to 23.8%), respectively. The FAINT score tended to be more accurate than unstructured physician judgment: area under the curve 0.704 (95% CI 0.669 to 0.739) versus 0.630 (95% CI 0.589 to 0.670).

CONCLUSION

Among older adults with syncope or near syncope of potential cardiac cause, a FAINT score of zero had a reasonably high sensitivity for excluding death and serious cardiac outcomes at 30 days. If externally validated, this tool could improve resource use for this common condition.

Clinical Benefit of Hospitalization for Older Adults With Unexplained Syncope: A Propensity-Matched Analysis

STUDY OBJECTIVE

Many adults with syncope are hospitalized solely for observation and testing. We seek to determine whether hospitalization versus outpatient management for older adults with unexplained syncope is associated with a reduction in postdisposition serious adverse events at 30 days.

METHODS

We performed a propensity score analysis using data from a prospective, observational study of older adults with unexplained syncope or near syncope who presented to 11 emergency departments (EDs) in the United States. We enrolled adults (≥60 years) who presented with syncope or near syncope. We excluded patients with a serious diagnosis identified in the ED. Clinical and laboratory data were collected on all patients. The primary outcome was rate of post-ED serious adverse events at 30 days.

RESULTS

We enrolled 2,492 older adults with syncope and no serious ED diagnosis from April 2013 to September 2016. Mean age was 73 years (SD 8.9 years), and 51% were women. The incidence of serious adverse events within 30 days after the index visit was 7.4% for hospitalized patients and 3.19% for discharged patients, representing an unadjusted difference of 4.2% (95% confidence interval 2.38% to 6.02%). After propensity score matching on risk of hospitalization, there was no statistically significant difference in serious adverse events at 30 days between the hospitalized group (4.89%) and the discharged group (2.82%) (risk difference 2.07%; 95% confidence interval -0.24% to 4.38%).

CONCLUSION

In our propensity-matched sample of older adults with unexplained syncope, for those with clinical characteristics similar to that of the discharged cohort, hospitalization was not associated with improvement in 30-day serious adverse event rates.

Evaluating patients presenting to the emergency department after syncope: validation of the Canadian Syncope Risk Score

BACKGROUND

Syncope is a common problem but can have any of a broad range of underlying causes. Initial evaluation of the patient in the emergency department often does not identify a specific cause, and the cornerstone of management is reliable risk stratification with clinical decision rules.

OBJECTIVES

The primary objective is to validate the utility and safety of the Canadian Syncope Risk Score (CSRS) as a clinical decision rule when assessing patients who present with syncope to Australian emergency departments. Our secondary objective is to evaluate the economic benefits of diverting patients with syncope at low risk of serious adverse events from admission to hospital.

METHODS AND ANALYSIS

Prospective, observational study. Patients aged 18 years or more who present to the emergency department (ED) after syncope in the preceding 24 hours and have returned to their baseline state will be enrolled. Patients will be contacted by telephone to determine whether they have experienced any adverse events within 30 days of their initial presentation to the ED. The CSRS will be applied retrospectively to determine the relationship between whether patients were admitted to hospital or discharged home and the reporting of serious adverse events for each CSRS risk level. We will also undertake a cost-effectiveness analysis from the health care perspective.

ETHICS APPROVAL

Prince Charles Hospital Human Research Ethics Committee (reference, HREC/17/QPCH/48).

DISSEMINATION OF RESULTS

Outcomes will be disseminated by Queensland Health and the funding body via social media, presented at local and national emergency medicine conferences, and published in international emergency medicine and health economics journals.

CLINICAL TRIALS REGISTRATION

Not applicable.

The Yield of Computed Tomography of the Head Among Patients Presenting With Syncope: A Systematic Review

BACKGROUND

Overuse of head computed tomography (CT) for syncope has been reported. However, there is no literature synthesis on this overuse. We undertook a systematic review to determine the use and yield of head CT and risk factors for serious intracranial conditions among syncope patients.

METHODS

We searched Embase, Medline, and Cochrane databases from inception until June 2017. Studies including adult syncope patients with part or all of patients undergoing CT head were included. We excluded case reports, reviews, letters, and pediatric studies. Two independent reviewers screened the articles and collected data on CT head use, diagnostic yield (proportion with acute hemorrhage, tumors or infarct), and risk of bias. We report pooled percentages, I² , and Cochran's Q-test.

RESULTS

Seventeen articles with 3,361 syncope patients were included. In eight ED studies (n = 1,669), 54.4% (95% confidence interval [CI] = 34.9%-73.2%) received head CT with a 3.8% (95% CI = 2.6%-5.1%) diagnostic yield and considerable heterogeneity. In six in-hospital studies (n = 1,289), 44.8% (95% CI = 26.4%-64.1%) received head CT with a 1.2% (95% CI = 0.5%-2.2%) yield and no heterogeneity. In two articles, all patients had CT (yield 2.3%) and the third enrolled patients ≥ 65 years old (yield 7.7%). Abnormal neurologic findings, age ≥ 65 years, trauma, warfarin use, and seizure/stroke history were identified as risk factors. The quality of all articles referenced was strong.

CONCLUSION

More than half of patients with syncope underwent CT head with a diagnostic yield of 1.1% to 3.8%. A future large prospective study is needed to develop a robust risk tool.

Effects of loss of consciousness on maxillofacial fractures in simple falls

BACKGROUND/AIMS

Loss of consciousness while falling is reported to increase the risk of more severe injury. However, few studies of maxillofacial injuries have been reported. The aim of this study was to investigate the effects of loss of consciousness on maxillofacial fractures in falls on a level surface (simple falls).

MATERIAL AND METHODS

Patients with maxillofacial fractures caused by simple falls were subdivided into two categories: patients who fell without loss of consciousness and patients who fell with loss of consciousness, according to the Guidelines for the Diagnosis and Management of Syncope (version 2009). The severity of the injuries was compared between these two groups.

RESULTS

In 413 patients with maxillofacial fractures, 58 cases were falls without loss of consciousness, and 44 cases were falls with loss of consciousness. In falls with loss of consciousness, 54.5% were reflex syncope, followed by syncope due to orthostatic hypotension (15.9%), epilepsy (15.9%), and cardiac syncope (9.1%). The average number of fracture lines in the mandible was significantly lower in falls without loss of consciousness (1.53 ± 0.7) than in falls with loss of consciousness (2.00 ± 1.00) (P = 0.045). The average Facial Injury Severity Scale score was lower in falls without loss of consciousness (2.24 ± 1.20) than in falls with loss of consciousness (2.68 ± 1.39). Fractures of other parts of the body were significantly more common in falls without loss of consciousness (22.2%) than in falls with loss of consciousness (9.1%) (P = 0.0135).

CONCLUSIONS

Patients with loss of consciousness and maxillofacial fractures due to simple falls showed a tendency to sustain more severe maxillofacial injuries than those without loss of consciousness.

Variation in diagnostic testing for older patients with syncope in the emergency department

BACKGROUND

Older adults presenting with syncope often undergo intensive diagnostic testing with unclear benefit. We determined the variation, frequency, yield, and costs of tests obtained to evaluate older persons with syncope.

METHODS

We conducted a prospective, multicenter observational cohort study in 11 academic emergency departments in the United States of 3686 patients aged ≥60 years presenting with syncope or presyncope. We measured the frequency, variation, yield, and costs (based on Medicare payment tables) of diagnostic tests performed at the index visit.

RESULTS

While most study rates were similar across sites, some were notably discordant (e.g., carotid ultrasound: mean 9.5%, range 1.1% to 49.3%). The most frequently-obtained diagnostic tests were initial troponin (88.6%), chest x-ray (75.1%), head CT (42.5%) and echocardiogram (35.5%). The yield or proportion of abnormal findings by diagnostic test ranged from 1.9% (electrocardiogram) to 42.0% (coronary angiography). Among the most common tests, echocardiogram had the highest proportion of abnormal results at 22.1%. Echocardiogram was an outlier in total cost at $672,648, and had a cost per abnormal test of $3129.

CONCLUSION

Variation in diagnostic testing in older patients presenting with syncope exists. The yield and cost per abnormal result for common tests obtained to evaluate syncope are also highly variable. Selecting tests based on history and examination while also prioritizing less resource intensive and higher yield tests may ensure a more informed and cost-effective approach to evaluating older patients with syncope.

[Determination of prognostic value of the OESIL risk score at 6 months in a Colombian cohort with syncope evaluated in the emergency department; first Latin American experience]

OBJECTIVES

To establish the prognostic value, with sensitivity, specificity, positive predictive value, and negative predictive value for the OESIL syncope risk score to predict the presentation of severe outcomes (death, invasive interventions, and readmission) after 6 months of observation in adults who consulted the emergency department due to syncope.

METHODS

Observational, prospective, and multicentre study with enrolment of subjects older than 18 years, who consulted in the emergency department due to syncope. A record was mad of the demographic and clinical information of all patients. The OESIL risk score was calculated, and severe patient outcomes were followed up during a 6 month period using telephone contact.

RESULTS

A total of 161 patients met the inclusion criteria and were followed up for 6 months. A score above or equal to 2 in the risk score, classified as high risk, was present in 72% of the patients. The characteristics of the risk score to predict the combined outcome of mortality, invasive interventions, and readmission for a score above or equal to 2 were 75.7, 30.5, 43.1, and 64.4% for sensitivity, specificity, positive predictive value, and negative predictive value, respectively.

CONCLUSIONS

A score above or equal to 2 in the OESIL risk score applied in Colombian population was of limited use to predict the studied severe outcomes. This score will be unable to discriminate between patients that benefit of early admission and further clinical studies.

Prevalence of pulmonary embolism in syncope patients

Clinical question

How often is pulmonary embolism (PE) found in patients admitted for syncope?

Article chosen

Prandoni P, Lensing A, Prins M, et al. Prevalence of pulmonary embolism among patients hospitalized for syncope (PESIT). N Engl J Med 2016;375:1524-31, doi: 10.1056/NEJMoa1602172.

Objective

To determine the prevalence of PE in patients hospitalized for a first episode of syncope.

Application of outpatient cardiac testing among emergency department patients with syncope

OBJECTIVES

2.6% of ED syncope patients will suffer cardiac serious adverse events (SAEs) within 30 days of disposition, and outpatient cardiac testing can improve patient safety. The objective is to determine whether outpatient cardiac testing for ED syncope patients is being appropriately ordered after discharge. To this end, we describe the proportion of high-risk and non-high (low and medium)-risk ED syncope patients as per the Canadian Syncope Risk Score (CSRS) who have a SAE after ED discharge, and the proportion referred for outpatient cardiac testing.

METHODS

Our multicentre prospective cohort study enrolled adult syncope patients between 2010 and 2014 in five academic EDs. We collected patient characteristics, disposition, CSRS predictors, outpatient referrals and testing results (Holter, echocardiography), and 30-day adjudicated SAE (death due to unknown/cardiac cause, myocardial infarction, arrhythmia and structural heart disease). We used descriptive statistics (mean, SD) to report our results.

RESULTS

Of 3584 enrolled patients (mean age 50.9 years, 57.7% women), 800 patients (22.3%) received an outpatient referral. Of these 800 patients, 40.3% of the non-high-risk patients (305/756) and 54.5% of the high-risk patients (24/44) received outpatient cardiac testing. Of all patients who received cardiac testing, five (1.5%; 95% CI 0.6% to 3.5%) suffered outpatient SAE (60.0% arrhythmias). Of all patients who did not receive cardiac testing, four patients (0.9%; 95% CI 0.3% to 2.2%) suffered SAE (all arrhythmias). Of the 20 (45.5%) high-risk patients who did not receive testing, two patients (10.0%; 95% CI 2.8% to 30.1%) suffered arrhythmias outside the hospital, while among the 451 (59.7%) non-high-risk patients, only two (0.4%; 95% CI 0.1% to 1.6%) suffered outpatient arrhythmias.

CONCLUSION

Outpatient cardiac testing is largely underused, especially among high-risk ED syncope patients. Better guidelines for outpatient cardiac testing are needed, as the practice is highly variable and mismatched with patient risk.

Reasons for Hospitalization Among Emergency Department Patients With Syncope

BACKGROUND

Variations in syncope management exist. Our objective was to identify the reasons for consultations and hospitalizations and outcomes among emergency department (ED) syncope patients.

METHODS

We conducted a prospective cohort study to enroll adult syncope patients at five EDs. We collected baseline characteristics, reasons for consultation and hospitalization, and hospital length of stay. Adjudicated 30-day serious adverse events (SAEs) including death, myocardial infarction, arrhythmia, structural heart disease, pulmonary embolism, significant hemorrhage, and procedural intervention. We used descriptive analysis.

RESULTS

From 4,064 enrolled patients (mean ± SD age = 53.1 ± 23.2 years; 55.9% female), 3,255 (80.1%) were discharged directly by the ED physician. Of those with no SAEs identified in the ED (n = 600), 42.8% of referrals and 46.5% of hospitalizations were for suspected arrhythmias, and 71.2% of patients hospitalized for arrhythmias had no cause identified. SAEs among groups were 9.7% in total, 2.5% discharged by ED physician, 3.4% discharged by consultant, 21.7% as inpatient, and 4.8% following discharge from hospital. The median hospital length of stay for suspected arrhythmias was 5 days (interquartile range = 3 to 8 days).

CONCLUSION

Cardiac syncope, particularly suspected arrhythmia, was the major reason for ED referrals and hospitalization. The majority of patients hospitalized for cardiac monitoring had no identified cause. An important number of patients suffered SAEs, particularly arrhythmias, outside the hospital. Development of a risk-stratification tool and out-of-hospital cardiac monitoring strategy should improve patient safety and save substantial resources.

Development of the Canadian Syncope Risk Score to predict serious adverse events after emergency department assessment of syncope

BACKGROUND

Syncope can be caused by serious conditions not evident during initial evaluation, which can lead to serious adverse events, including death, after disposition from the emergency department. We sought to develop a clinical decision tool to identify adult patients with syncope who are at risk of a serious adverse event within 30 days after disposition from the emergency department.

METHODS

We prospectively enrolled adults (age ≥ 16 yr) with syncope who presented within 24 hours after the event to 1 of 6 large emergency departments from Sept. 29, 2010, to Feb. 27, 2014. We collected standardized variables at index presentation from clinical evaluation and investigations. Adjudicated serious adverse events included death, myocardial infarction, arrhythmia, structural heart disease, pulmonary embolism, serious hemorrhage and procedural interventions within 30 days.

RESULTS

We enrolled 4030 patients with syncope; the mean age was 53.6 years, 55.5% were women, and 9.5% were admitted to hospital. Serious adverse events occurred in 147 (3.6%) of the patients within 30 days after disposition from the emergency department. Of 43 candidate predictors examined, we included 9 in the final model: predisposition to vasovagal syncope, heart disease, any systolic pressure reading in the emergency department < 90 or > 180 mm Hg, troponin level above 99th percentile for the normal population, abnormal QRS axis (< -30° or > 100°), QRS duration longer than 130 ms, QTc interval longer than 480 ms, emergency department diagnosis of cardiac syncope and emergency department diagnosis of vasovagal syncope (C statistic 0.88, 95% confidence interval [CI] 0.85-0.90; optimism 0.015; goodness-of-fit p = 0.11). The risk of a serious adverse event within 30 days ranged from 0.4% for a score of -3 to 83.6% for a score of 11. The sensitivity was 99.2% (95% CI 95.9%-100%) for a threshold score of -2 or higher and 97.7% (95% CI 93.5%-99.5%) for a threshold score of -1 or higher.

INTERPRETATION

The Canadian Syncope Risk Score showed good discrimination and calibration for 30-day risk of serious adverse events after disposition from the emergency department. Once validated, the tool will be able to accurately stratify the risk of serious adverse events among patients presenting with syncope, including those at low risk who can be discharged home quickly.

Derivation of a risk scale and quantification of risk factors for serious adverse events in adult emergency department syncope patients

BACKGROUND

Determining the appropriate disposition of emergency department (ED) syncope patients is challenging. Previously developed decision tools have poor diagnostic test characteristics and methodological flaws in their derivation that preclude their use. We sought to develop a scale to risk-stratify adult ED syncope patients at risk for serious adverse events (SAEs) within 30 days.

METHODS

We conducted a medical record review to include syncope patients age ≥ 16 years and excluded patients with ongoing altered mental status, alcohol or illicit drug use, seizure, head injury leading to loss of consciousness, or severe trauma requiring admission. We collected 105 predictor variables (demographics, event characteristics, comorbidities, medications, vital signs, clinical examination findings, emergency medical services and ED electrocardiogram/monitor characteristics, investigations, and disposition variables) and information on the occurrence of predefined SAEs. Univariate and multiple logistic regression analyses were performed.

RESULTS

Among 505 enrolled patient visits, 49 (9.7%) suffered an SAE. Predictors of SAE and their resulting point scores were as follows: age ≥ 75 years (1), shortness of breath (2), lowest ED systolic blood pressure < 80 mm Hg (2), Ottawa Electrocardiographic Criteria present (2), and blood urea nitrogen > 15 mmol/L (3). The final score calculated by addition of the individual scores for each variable (range 0-10) was found to accurately stratify patients into low risk (score < 1, 0% SAE risk), moderate risk (score 1, 3.7% SAE risk), or high risk (score > 1, ≥ 10% SAE risk).

CONCLUSION

We derived a risk scale that accurately predicts SAEs within 30 days in ED syncope patients. If validated, this will be a potentially useful clinical decision tool for emergency physicians, may allow judicious use of health care resources, and may improve patient care and safety.

Prognostic value of cardiac biomarkers in the risk stratification of syncope: a systematic review

The role of cardiac biomarkers in risk stratification of syncope is unclear. We undertook a systematic review to assess their predictive value for short-term major adverse cardiovascular events (MACE). We conducted a systematic review using MEDLINE, EMBASE, DARE and Cochrane databases from inception to July 2014. We included studies involving adult syncope patients that evaluated cardiac biomarker levels for risk stratification during acute management and excluded case reports, reviews and studies involving children. Primary outcome (MACE) included death, cardiopulmonary resuscitation, myocardial infarction (MI), structural heart disease, pulmonary embolism, significant hemorrhage or cardiac procedural interventions. Secondary outcome analysis assessed for prediction of MI, cardiac syncope and death. Two reviewers extracted patient-level data based on the cut-off reported. Pooled sensitivities and specificities were calculated using patient-level data. A total of 1862 articles were identified, and 11 studies with 4246 patients were included. Studies evaluated 3 biomarkers: contemporary troponin (2693 patients), natriuretic peptides (1353 patients) and high-sensitive troponin (819 patients). The pooled sensitivities and specificities for MACE were: contemporary troponin 0.29 (95 % CI 0.24, 0.34) and 0.88 (95 % CI 0.86, 0.89); natriuretic peptides 0.77 (95 % CI 0.69, 0.85) and 0.73 (95 % CI 0.70, 0.76); high-sensitive troponin 0.74 (95 % CI 0.65, 0.83) and 0.65 (95 % CI 0.62, 0.69), respectively. Natriuretic peptides and high-sensitive troponin showed good diagnostic characteristics for both primary and secondary outcomes. Natriuretic peptides and high-sensitive troponin might be useful in risk stratification.

Validation of EGSYS Score in Prediction of Cardiogenic Syncope

Introduction. Evaluation of Guidelines in Syncope Study (EGSYS) is designed to differentiate between cardiac and noncardiac causes of syncope. The present study aimed to evaluate the accuracy of this predictive model. Methods. In this prospective cross-sectional study, screening performance characteristics of EGSYS-U (univariate) and EGSYS-M (multivariate) in prediction of cardiac syncope were calculated for syncope patients who were referred to the emergency department (ED). Results. 198 patients with mean age of 59.26 ± 19.5 years were evaluated (62.3% male). 115 (58.4%) patients were diagnosed with cardiac syncope. Area under the ROC curve was 0.818 (95% CI: 0.75–0.87) for EGSYS-U and 0.805 (CI 95%: 0.74–0.86) for EGSYS-M (p = 0.53). Best cut-off point for both models was ≥3. Sensitivity and specificity were 86.08% (95% CI: 78.09–91.59) and 68.29% (95% CI: 56.97–77.86) for EGSYS-U and 91.30% (95% CI: 84.20–95.52) and 57.32% (95% CI: 45.92–68.02) for EGSYS-M, respectively. Conclusion. The results of this study demonstrated the acceptable accuracy of EGSYS score in predicting cardiogenic causes of syncope at the ≥3 cut-off point. It seems that using this model in daily practice can help physicians select at risk patients and properly triage them.

National cost savings from observation unit management of syncope

OBJECTIVES

Syncope is a frequent emergency department (ED) presenting complaint and results in a disproportionate rate of hospitalization with variable management strategies. The objective was to estimate the annual national cost savings, reduction in inpatient hospitalizations, and reduction in hospital bed hours from implementation of protocolized care in an observation unit.

METHODS

We created a Monte Carlo simulation by building a model that reflects current clinical practice in the United States and uses inputs gathered from the most recent available peer-reviewed literature and national survey data. ED visit volume was adjusted to reflect observation unit availability and the portion of observation visits requiring subsequent inpatient care. A recent multicenter randomized controlled study informed the cost savings and length of stay reduction per observation unit visit model inputs. The study population included patients aged 50 years and older with syncope deemed at intermediate risk for serious 30-day cardiovascular outcomes.

RESULTS

The mean (±SD) annual cost savings was estimated to be $108 million (±$89 million) from avoiding 235,000 (±13,900) inpatient admissions, resulting in 4,297,000 (±1,242,000) fewer hospital bed hours.

CONCLUSIONS

The potential national cost savings for managing selected patients with syncope in a dedicated observation unit is substantial. Syncope is one of many conditions suitable for care in an observation unit as an alternative to an inpatient setting. As pressure to decrease hospital length of stay and bill short-stay hospitalizations as observation increases, syncope illustrates the value of observation unit care.

Emergency department management of syncope: need for standardization and improved risk stratification

Variations in emergency department (ED) syncope management have not been well studied. The goals of this study were to assess variations in management, and emergency physicians' risk perception and disposition decision making. We conducted a prospective study of adults with syncope in six EDs in four cities over 32 months. We collected patient characteristics, ED management, disposition, physicians' prediction probabilities at index presentation and followed patients for 30 days for serious outcomes: death, myocardial infarction (MI), arrhythmia, structural heart disease, pulmonary embolism, significant hemorrhage, or procedural interventions. We used descriptive statistics, ROC curves, and regression analyses. We enrolled 3662 patients: mean age 54.3 years, and 12.9 % were hospitalized. Follow-up data were available for 3365 patients (91.9 %) and 345 patients (10.3 %) suffered serious outcomes: 120 (3.6 %) after ED disposition including 48 patients outside the hospital. After accounting for differences in patient case mix, the rates of ED investigations and disposition were significantly different (p < 0.0001) across the four study cities; as were the rates of 30-day serious outcomes (p < 0.0001) and serious outcomes after ED disposition (p = 0.0227). There was poor agreement between physician risk perception and both observed event rates and referral patterns (p < 0.0001). Only 76.7 % (95 % CI 68.1-83.6) of patients with serious outcomes were appropriately referred. There are large and unexplained differences in ED syncope management. Moreover, there is poor agreement between physician risk perception, disposition decision making, and serious outcomes after ED disposition. A valid risk-stratification tool might help standardize ED management and improve disposition decision making.

Syncope: a review of emergency department management and disposition

Syncope is defined as a transient loss of consciousness due to cerebral hypoperfusion with spontaneous return to baseline function without intervention. It is a common chief complaint of patients presenting to the emergency department. The differential diagnosis for syncope is broad and the management varies significantly depending on the underlying etiology. In the emergency department, determining the cause of a syncopal episode can be difficult. However, a thorough history and certain physical exam findings can assist in evaluating for life-threatening diagnoses. Risk-stratifying patients into low, moderate and high-risk groups can assist in medical decision making and help determine the patient's disposition. Advancements in ambulatory monitoring have made it possible to obtain prolonged cardiac evaluations of patients in the outpatient setting. This review will focus on the diagnosis and management of the various types of syncope.

Syncope: diagnosis and management

Syncope is defined as transient loss of consciousness due to global cerebral hypoperfusion. It is characterized by having a relatively rapid onset, brief duration with spontaneous and full recovery. The major challenge in the evaluation of patients with syncope is that most patients are asymptomatic at the time of their presentation. A thorough history and physical examination including orthostatic assessment are crucial for making the diagnosis. After initial evaluation, short-term risk assessment should be performed to determine the need for admission. If the short-term risk is high, inpatient evaluation is needed. If the short-term risk is low, outpatient evaluation is recommended. In patients with suspected cardiac syncope, monitoring is indicated until a diagnosis is made. In patients with suspected reflex syncope or orthostatic hypotension, outpatient evaluation with tilt-table testing is appropriate. Syncope units have been shown to improve the rate of diagnosis while reducing cost and thus are highly recommended.

Syncope risk stratification tools vs clinical judgment: an individual patient data meta-analysis

BACKGROUND

There have been several attempts to derive syncope prediction tools to guide clinician decision-making. However, they have not been largely adopted, possibly because of their lack of sensitivity and specificity. We sought to externally validate the existing tools and to compare them with clinical judgment, using an individual patient data meta-analysis approach.

METHODS

Electronic databases, bibliographies, and experts in the field were screened to find all prospective studies enrolling consecutive subjects presenting with syncope to the emergency department. Prediction tools and clinical judgment were applied to all patients in each dataset. Serious outcomes and death were considered separately during emergency department stay and at 10 and 30 days after presenting syncope. Pooled sensitivities, specificities, likelihood ratios, and diagnostic odds ratios, with 95% confidence intervals, were calculated.

RESULTS

Thirteen potentially relevant papers were retrieved (11 authors). Six authors agreed to share individual patient data. In total, 3681 patients were included. Three prediction tools (Osservatorio Epidemiologico sulla Sincope del Lazio [OESIL], San Francisco Syncope Rule [SFSR], Evaluation of Guidelines in Syncope Study [EGSYS]) could be assessed by the available datasets. None of the evaluated prediction tools performed better than clinical judgment in identifying serious outcomes during emergency department stay, and at 10 and 30 days after syncope.

CONCLUSIONS

Despite the use of an individual patient data approach to reduce heterogeneity among studies, a large variability was still present. Current prediction tools did not show better sensitivity, specificity, or prognostic yield compared with clinical judgment in predicting short-term serious outcome after syncope. Our systematic review strengthens the evidence that current prediction tools should not be strictly used in clinical practice.

Syncope

Syncope is common representing approximately 3% of ED visits and up to 6% of hospital admissions, with a cost close to 2 billion dollars per year. Diagnostic testing is often poorly sensitive and evaluations commonly lack a standardized approach. A mindful and systematic approach can increase sensitivity and improve diagnostic accuracy. A thorough history and physical exam is paramount, as conclusions drawn from the history and exam will guide further assessment. Developing a strategy for the first and, if necessary, subsequent tests will improve the accuracy of identifying the etiology of syncope and reduce cost. Although syncope has a favorable prognosis, identification of patients with structural heart disease is critical, as these patients are at greatest risk for mortality. Several risk scoring systems have been developed to help separate high risk from low risk patients.

Priorities for emergency department syncope research

STUDY OBJECTIVES

There is limited evidence to guide the emergency department (ED) evaluation and management of syncope. The First International Workshop on Syncope Risk Stratification in the Emergency Department identified key research questions and methodological standards essential to advancing the science of ED-based syncope research.

METHODS

We recruited a multinational panel of syncope experts. A preconference survey identified research priorities, which were refined during and after the conference through an iterative review process.

RESULTS

There were 31 participants from 7 countries who represented 10 clinical and methodological specialties. High-priority research recommendations were organized around a conceptual model of ED decisionmaking for syncope, and they address definition, cohort selection, risk stratification, and management.

CONCLUSION

We convened a multispecialty group of syncope experts to identify the most pressing knowledge gaps and defined a high-priority research agenda to improve the care of patients with syncope in the ED.

Syncope risk stratification in the ED

Syncope may be the final common presentation of a number of clinical conditions spanning benign (i.e. neurally-mediated syncope) to life-threatening diseases (i.e. cardiac syncope). Hospitalization rate after a syncopal episode is high. An effective risk stratification is crucial to identify patients at risk of poor prognosis in the short term period to avoid unnecessary hospital admissions. The decision to admit or discharge a syncope patient from the ED is often based on the physician's clinical judgment. In recent years, several prognostic tools (i.e. clinical prediction rules and risk scores) have been developed to provide emergency physicians with accurate guidelines for hospital admission. At present, there are no compelling evidence that prognostic tools perform better than physician's clinical judgment in assessing the short-term outcome of syncope. However, the risk factors characterizing clinical prediction rules and risk scores may be profitably used by emergency doctors in their decision making, specifically whenever a syncope patient has to be discharged from ED or admitted to hospital. Patients with syncope of undetermined etiology, who are characterized by an intermediate-high risk profile after the initial evaluation, should be monitored in the ED. Indeed, data suggest that the 48h following syncope are at the highest risk for major adverse events. A new tool for syncope management is represented by the Syncope Unit in the ED or in an outpatient setting. Syncope Unit may reduce hospitalization and length of hospital stay. However, further studies are needed to clarify whether syncope patients' prognosis can be also improved.

Risk stratification of adult emergency department syncope patients to predict short-term serious outcomes after discharge (RiSEDS) study

Background

While Canadian ED physicians discharge most syncope patients with no specific further follow-up, approximately 5% will suffer serious outcomes after ED discharge. The goal of this study is to prospectively identify risk factors and to derive a clinical decision tool to accurately predict those at risk for serious outcomes after ED discharge within 30 days.

Methods/Design

We will conduct a prospective cohort study at 6 Canadian EDs to include adults with syncope and exclude patients with loss of consciousness > 5 minutes, mental status changes from baseline, obvious witnessed seizure, or head trauma prior to syncope. Emergency physicians will collect standardized clinical variables including historical features, physical findings, and results of immediately available tests (blood, ECG, and ED cardiac monitoring) prior to ED discharge/hospital admission. A second emergency physician will evaluate approximately 10% of study patients for interobserver agreement calculation of predictor variables. The primary outcome will be a composite serious outcome occurring within 30 days of ED discharge and includes three distinct categories: serious adverse events (death, arrhythmia); identification of serious underlying disease (structural heart disease, aortic dissection, pulmonary embolism, severe pulmonary hypertension, subarachnoid hemorrhage, significant hemorrhage, myocardial infarction); or procedures to treat the cause of syncope. The secondary outcome will be any of the above serious outcomes either suspected or those occurring in the ED. A blinded Adjudication Committee will confirm all serious outcomes. Univariate analysis will be performed to compare the predictor variables in patients with and without primary outcome. Variables with p-values <0.2 and kappa values ≥0.60 will be selected for stepwise logistic regression to identify the risk factors and to develop the clinical decision tool. We will enroll 5,000 patients (with 125 positive for primary outcome) for robust identification of risk factors and clinical decision tool development.

Discussion

Once successfully developed, this tool will accurately risk-stratify adult syncope patients; however, validation and implementation will still be required. This program of research should lead to standardized care of syncope patients, and improve patient safety.

Syncope risk stratification in the emergency department

The overall risk for a patient entering the emergency department (ED) because of syncope ranges between 5% and 15%, and the mortality at 1 week is approximately 1%. The primary goal for the ED physician is thus to discriminate individuals at low risk, who can be safely discharged, from patients at high risk, who warrant a prompt hospitalization for monitoring and/or appropriate treatment. Different rules and risk scores have been proposed. More ad hoc studies are needed to define the prognostic and diagnostic roles of the brain natriuretic peptide and other noninvasive laboratory markers.

Validation of the San Francisco Syncope Rule in two hospital emergency departments in an Asian population

OBJECTIVES

The objective was to externally validate the ability of the San Francisco Syncope Rule (SFSR) to accurately identify patients who will experience a 7-day serious clinical event in an Asian population.

METHODS

This was a prospective cohort study, with a sample of adult patients with syncope and near-syncope enrolled. Patients 12 years old and below and patients with loss of consciousness after head trauma, a witnessed seizure, with known alcohol or illicit drug ingestion, and altered level of consciousness or persistent new neurologic deficits were excluded. The patients were evaluated for the presence of one or more of the five SFSR variables: shortness of breath, history of heart failure, hematocrit <30%, systolic blood pressure <90 mm Hg, and abnormal electrocardiogram (ECG). The patients were followed up by medical record review or telephone interview. Seven-day outcomes were death, arrhythmia, myocardial infarction, acute pulmonary edema, significant structural heart disease, pulmonary embolism, major cardiac procedure, stroke, subarachnoid hemorrhage, major bleeding, and anemia.

RESULTS

A total of 1,250 patients from two centers were recruited. Fifty-six patients were excluded from primary analysis because of incomplete data (n = 55) and/or they were noncontactable for follow-up (n = 32). Of the 1,194 patients analyzed, 138 patients (11.6%) experienced adverse outcomes at 7 days. The rule performed with a sensitivity of 94.2% (95% confidence interval [CI] = 89.0% to 97.0%) and a specificity of 50.8% (95% CI = 47.7% to 53.8%).

CONCLUSIONS

In this study, SFSR rule had a sensitivity of 94.2%. This suggests caution on the strict application of the rule to all patients presenting with syncope. It should only be used as an aide in clinical decision-making in this population.

Key challenges in the current management of syncope

Patients commonly present with syncope at emergency departments and other facilities for urgent care. Syncope is understood by physicians to be a transient, self-terminating period of cerebral hypoperfusion that usually results from systemic hypotension, and clinical guidelines for the care of patients with presumed syncope are available. However, the diagnosis and management of such patients continue to pose important diagnostic, therapeutic, and economic challenges, which are the focus of this Review. First, we discuss how to improve symptom characterization to distinguish syncope from other forms of transient loss of consciousness and syncope mimics. Second, we compare methods of risk stratification in patients with suspected syncope, and recommend the introduction of syncope clinics with enhanced interdisciplinary collaboration to optimize patient care at reduced expense. Third, we highlight the importance of the appropriate selection of diagnostic tools and treatment strategies in these syncope clinics. Finally, we address the difficulties associated with therapy for the most-common form of syncope--vasovagal or reflex syncope.

Standardized reporting guidelines for emergency department syncope risk-stratification research

There is increasing research interest in the risk stratification of emergency department (ED) syncope patients. A major barrier to comparing and synthesizing existing research is wide variation in the conduct and reporting of studies. The authors wanted to create standardized reporting guidelines for ED syncope risk-stratification research using an expert consensus process. In that pursuit, a panel of syncope researchers was convened and a literature review was performed to identify candidate reporting guideline elements. Candidate elements were grouped into four sections: eligibility criteria, outcomes, electrocardiogram (ECG) findings, and predictors. A two-round, modified Delphi consensus process was conducted using an Internet-based survey application. In the first round, candidate elements were rated on a five-point Likert scale. In the second round, panelists rerated items after receiving information about group ratings from the first round. Items that were rated by >80% of the panelists at the two highest levels of the Likert scale were included in the final guidelines. There were 24 panelists from eight countries who represented five clinical specialties. The panel identified an initial set of 183 candidate elements. After two survey rounds, the final reporting guidelines included 92 items that achieved >80% consensus. These included 10 items for study eligibility, 23 items for outcomes, nine items for ECG abnormalities, and 50 items for candidate predictors. Adherence to these guidelines should facilitate comparison of future research in this area.

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.