Prospective evaluation of the use of the thrombolysis in myocardial infarction score as a risk stratification tool for chest pain patients admitted to an ED observation unit

Background

The Thrombolysis in Myocardial Infarction (TIMI) score has shown use in predicting 30-day and 1-year outcomes in emergency department (ED) patients with potential acute coronary syndrome. Few studies have evaluated the TIMI score in risk stratifying patients selected for the ED observation Unit (EDOU). Risk stratification of patients in this group could identify those at risk for significant cardiac events. Our goal was to evaluate TIMI use for risk stratification in this population and compare outcomes among differing scores.

Methods

A prospective observational study with 30-day telephone follow-up for a 12 month period. Baseline data, outcomes related to EDOU stay, admission, and 30-day outcomes were recorded. TIMI scores were calculated for each patient placed in EDOU. TIMI score was not utilized in the decision to place patients in observation.

Results

N = 552. Composite outcomes recorded were myocardial infarction, revascularization, or death either during the EDOU stay, inpatient admission, or the 30-day follow-up. Eighteen composite outcomes were recorded: stent (12 patients), coronary artery bypass graft (3 patients), myocardial infarction and stent (2 patients), and myocardial infarction, and coronary artery bypass graft (1 patient). Distribution by TIMI score was: 0 (102 patients), 1 (196), 2 (142), 3 (72), 4 (27), and 5 (5). Risk of composite outcome increased by score: 0 (1%), 1 (2.6%), 2 (2.1%), 3 (6.9%), 4 (11.1%), and 5 (20%). Those with an intermediate risk score (3-5) were also more likely to require admission (15.4% vs 9.8%, P = .048).

Conclusion

The TIMI risk score may serve as an effective risk stratification tool among chest pain patients selected for EDOU placement. Patients with intermediate-risk by TIMI may be considered for inpatient admission and/or more aggressive evaluation and therapy.     

Impact of trauma activation on the ED length of stay for nontraumatic patients

Introduction

Trauma activation prioritizes hospital resources for the assessment and treatment of trauma patient over all patients in the emergency department (ED). We hypothesized that length of stay (LOS) is longer for nontrauma patients during a trauma activation.

Methods

A retrospective, case-control chart review was conducted in a level I trauma center. Cases consist of patients who present 1 hour before and after the presentation of the trauma activation. Controls were patients presenting to the ED during the same period exactly 1 week before and after the cases. Confounding variables measured included sex, age, arrivals, and census for the 3 areas.

Results

Two hundred ninety-four trauma events occurred from January 1 until September 30, 2009. A significant difference was found between LOS of patients seen during a trauma activation with an average increase of 10.7 minutes in LOS (P =.0082; 95% confidence interval [CI], 2.8-18.7). This difference is attributable to the middle acuity area of the ED, in which the average increase in LOS was 20.3 minutes (P = .0004; 95% CI, 9.1-31.5). Significant LOS difference was not found when a trauma activation had an LOS of less than 60 minutes (P = .30; 95% CI, −7.1-61.7 for trauma LOS <60 minutes vs P = .02; 95% CI, 1.6-18.0 for trauma LOS ≥60 minutes).

Conclusion

This retrospective case-control chart review identified an increase in ED LOS for patient presenting during trauma activations. Resource prioritization should be accounted for during times when these critical patients enter the ED.     

Cardiology consultation reduces provocative testing rates in an ED observation unit

Background

In evaluating patients with chest pain, emergency department observation units (EDOUs) may use a staffing model in which emergency physicians determine patient testing (EP model) or a model similar to a chest pain unit (CPU) in which cardiologists determine provocative testing (CPU model).

Prospective evaluation of criteria for obtaining thoracolumbar radiographs in trauma patients

This study examined if use of clinical screening criteria for selective radiography of blunt trauma patients can identify all patients with thoracolumbar (TL) spine injuries. The study was a prospective cohort of patients undergoing TL spine radiographs following blunt trauma. Patients were considered at risk for TL spine injury if they had any of the following clinical criteria: 1) complaints of TL spine pain, 2) TL spine tenderness, 3) a decreased level of consciousness, 4) intoxication with ethanol or drugs, 5) a neurologic deficit, or 6) a painful distracting injury. Patients without any of these findings were considered at low risk for TL spine injury. Severity of mechanism of injury was also recorded. Data sheets were completed prior to TL radiography. Injury status was determined by the final faculty radiologist interpretation of all radiographic studies. A total of 2404 patients were enrolled. TL spine injuries were identified in 152 patients. Of these 152 patients with spine injuries, all 152 (100%, 95% confidence interval 98-100%) were considered high risk by having at least one of the high-risk criteria. These criteria have a specificity of 3.9%, a positive predictive value of 6.6%, and a negative predictive value of 100%. All of the high-risk criteria but intoxication with ethanol or drugs were important as sole predictors of TL spine injury. The use of high-risk clinical screening criteria identified virtually all blunt trauma patients with acute TL spine injuries. These criteria, however, have poor specificity and positive predictive value.     

Brain SPECT evaluation of amnestic ED patients after mild head trauma

A short period of amnesia is a common complaint after mild head injury. In this study we compare the duration of amnesia after mild head trauma to single photon emission computed tomography (SPECT) perfusion imaging shortly after admission to the emergency department (ED). Sixteen patients consecutively admitted to the ED were prospectively evaluated. The amnesia was scored according to the Extended Glasgow Coma Score. A computed tomography (CT) scan was performed to all patients. All patients had anterograde amnesia. Eleven patients had amnesia of grade 2 (69%) and 5 patients of grade 3 (31%). All patients had a normal CT scan. Twelve of sixteen patients (75%) showed regional perfusion abnormalities on the SPECT study. Decreased perfusion was observed at least in one region (8/12 patients had 2 abnormal regions). The logistic regression analysis showed that SPECT results significantly predicted the severity of amnesia (r = 0.9, P <.0001). Additionally, the SPECT accounted for approximately 84% of the variation in amnesia. We conclude that amnesia after mild head injury is associated with a high incidence of early regional cerebral perfusion abnormalities. Amnesia lasting more than half an hour is associated with bilateral cerebral hypoperfusion. SPECT evaluation in the ED may by a useful additional tool in the objective assessment of posttraumatic amnesia.     

The role of an emergency department observation unit in the management of trauma patients

During a 12-month period, 20,838 patients with acute traumatic injuries were seen in the Emergency Department (ED) of Denver General Hospital. Of these patients, 520 (2.5%) were admitted to the ED Observation Unit, a seven-bed acute care unit situated within the ED and sufficient data were available on 485 (93%) for inclusion into the study. Fifty-three (15.4%) of these observation unit patients required subsequent admission, 389 (80%) were discharged, and 16 (4%) left against medical advice. There were no observation unit deaths. These groups of patients were analyzed and compared with regard to severity of injury, length of stay, and discharge diagnosis. The observation unit is useful in the evaluation of blunt chest or abdominal trauma when work-up, including chest x-ray studies and peritoneal lavage, is initially negative and when drug or alcohol ingestion obscures the initial evaluation in the ED. An observation unit within the ED is cost-efficient and has proven very useful in the management of trauma victims.     

The effect of an observation unit on the rate of ED admission and discharge for pyelonephritis

Objectives

We sought to determine if the opening of an adult emergency department (ED) observation unit (OU) would impact the rate of hospital admission and ED discharges for pyelonephritis.

Methods

A retrospective cohort study was performed with all adult patients from October 2003 through December 2006 in the ED meeting inclusion criteria for pyelonephritis. Clinical, demographic, and laboratory data were recorded. Primary outcomes were rates of admission, ED discharge, and return ED visits before and after the opening of our OU. We compared admission, discharge, and readmission rates using the χ² test.

Results

Nine hundred thirty charts were reviewed with 633 included for analysis. Urine cultures were performed on 420 subjects with 71% being positive. The percentage of patients admitted to a hospital inpatient unit from the ED decreased from 36% to 26% (relative risk [RR], 0.73; P = .01) after opening the OU. The percentage of patients discharged home from the ED decreased from 65% to 51% (RR, 0.76; P < .001). Among OU patients, 29% were admitted to the hospital for further inpatient care. Emergency department recidivism was unchanged by opening the OU (RR, 0.86; P = .68).

Conclusions

The creation of an OU appears to influence admission decisions of ED physicians. We found that the creation of an OU significantly reduced hospital admissions for pyelonephritis but also significantly reduced ED discharges to home for pyelonephritis at our institution.     

Predictors of hospital admission after ED observation unit care

Background

Emergency department observation units (EDOUs) represent an opportunity to efficiently manage patients with common conditions requiring short-term hospital care. Understanding which patients are ultimately admitted to the hospital after care in an EDOU may enhance patient selection for EDOU care.

Methods

We conducted a retrospective analysis of US emergency department visits resulting in admission to observation status using the National Hospital Ambulatory Care Survey (NHAMCS) from 2009 to 2010, a nationally representative sample. We used survey-weighted logistic regression to identify predictors at the patient level, visit level, and hospital level for inpatient hospital admission after EDOU care.

Results

Between 2009 and 2010, there were 4.65 million patient visits (95% confidence interval [CI], 3.68-5.63) to EDOUs in the United States. Of those evaluated in an EDOU, 40.4% (95% CI, 34.5%-46.6%) were admitted to the hospital after EDOU care. Progressively older patient age was a strong predictor of hospital admission: patients age older than 65 years were more than 5 times more likely to be admitted than patients age younger than 18 years (odds ratio, 5.36; 95% CI, 2.26-12.73). The only other visit-level factor associated with admission was a reason for visit of chest pain; this was associated with a lower rate of hospital admission (odds ratio, 0.61; 95% CI, 0.41-0.91).

Conclusion

Across the United States in 2009 to 2010, older patient age was a strong predictor of admission after EDOU care, suggesting that older patients are more likely to require inpatient hospital services after EDOU care than younger patients.     

Serial hematocrit testing does not identify major injuries in trauma patients in an observation unit

Background

Routine serial hematocrit measurements are a component of the trauma evaluation for patients without serious injury identified on initial evaluation. We sought to determine whether serial hematocrit testing was useful in detecting significant intra-abdominal injuries in trauma patients in our observation unit.

Methods

We performed a retrospective chart review of all trauma patients placed in our observation unit over a 14-month period. Patients had received trauma surgery evaluation before placement in the observation unit and routinely received serial hematocrit testing (≥2 hematocrit levels) while in the observation unit. We compared trauma patients with a hematocrit drop of 5 points or more to those without a significant hematocrit drop.

Results

Three hundred sixty-five trauma patients were placed in the observation unit, and 310 patients (85%) had at least 2 hematocrits drawn during their stay. Of these patients, 20.6% had a hematocrit drop of 5 or more. Of patients with the hematocrit change, 18.8% were admitted to an inpatient unit from the observation unit compared to 9.3% of patients without a significant hematocrit change (P = .034). In one of these patients who had a computed tomography scan before observation admission, which demonstrated free fluid, the hematocrit drop assisted in diagnosing significant intra-abdominal injury.

Conclusion

Although serial hematocrit testing may be useful in specific situations, routine use of serial hematocrit testing in trauma patients at a level I trauma center's observation unit did not significantly aid in the detection of occult injury.     

Effect of advanced age and vital signs on admission from an ED observation unit

Objectives

The primary objective was to determine the relationship between advanced age and need for admission from an emergency department (ED) observation unit. The secondary objective was to determine the relationship between initial ED vital signs and admission.

Methods

We conducted a prospective, observational cohort study of ED patients placed in an ED-basedobservation unit. Multivariable penalized maximum likelihood logistic regression was used to identify independent predictors of need for hospital admission. Age was examined continuously and at acutoff of 65 years or more. Vital signs were examined continuously and at commonly accepted cutoffs.We additionally controlled for demographics, comorbid conditions, laboratory values, and observation protocol.

Results

Three hundred patients were enrolled, 12% (n = 35) were 65 years or older, and 11% (n = 33) required admission. Admission rates were 2.9% (95% confidence interval [CI], 0.07%-14.9%) in older adults and 12.1% (95% CI, 8.4%-16.6%) in younger adults. In multivariable analysis, age was not associated with admission (odds ratio [OR], 0.30; 95% CI, 0.05-1.67). Predictors of admission included systolic pressure 180 mm Hg or greater (OR, 4.19; 95% CI, 1.08-16.30), log Charlson comorbidity score (OR, 2.93; 95% CI, 1.57-5.46), and white blood cell count 14?000/mm³ or greater (OR, 11.35; 95% CI, 3.42-37.72).

Conclusions

Among patients placed in an ED observation unit, age 65 years or more is not associated with need for admission. Older adults can successfully be discharged from these units. Systolic pressure 180 mm Hg or greater was the only predictive vital sign. In determining appropriateness of patients selected for an ED observation unit, advanced age should not be an automatic disqualifying criterion.     

Assessment of urinary dipstick in patients admitted to an ED for blunt abdominal trauma

Introduction

Clinicians still face significant challenge in predicting intra-abdominal injuries in patients admitted to an emergency department for blunt abdominal trauma. This study was thus designed to investigate the value of dipstick urinalysis in patients with blunt abdominal trauma.

The effect of physician risk tolerance and the presence of an observation unit on decision making for ED patients with chest pain

Objectives

We sought to determine whether risk tolerance as measured by scales (malpractice fear scale [MFS], risk-taking scale [RTS], and stress from uncertainty scale [SUS]) is associated with decisions to admit or use computed tomography (CT) coronary angiogram and decisions to order cardiac markers in emergency department (ED) patients with chest pain. We also studied if the opening of an ED-based observation unit affected the relationship between risk scales and admission decisions.

Methods

Data from a prospective study of ED patients 30 years or older with chest pain were used. Risk scales were administered to ED attending physicians who initially evaluated them. Physicians were divided into quartiles for each separate risk scale. Fisher's exact test and logistic regression were used for statistical analysis.

Results

A total of 2872 patients were evaluated by 31 physicians. The most risk-averse quartile of RTS was associated with higher admission rates (78% vs 68%) and greater use of cardiac markers (83% vs 78%) vs the least risk-averse quartile. This was not true for MFS or SUS. Similar associations were observed in low-risk patients (Thrombolysis in Myocardial Infarction risk score of 0 or 1). The observation unit was not associated with a higher admission rate and did not modify the relationship between risk scales and admission rates.

Conclusion

The RTS was associated with the decision to admit or use computed tomography coronary angiogram, as well as the use of cardiac markers, whereas the MFS and SUS were not. The observation unit did not affect admission rates and nor did it affect how physician's risk tolerance affects admission decisions.     

Identifying patients with cellulitis who are likely to require inpatient admission after a stay in an ED observation unit

Background

Emergency department observation units (EDOU) are often used for patients with cellulitis to provide intravenous antibiotics followed by a transition to an oral regimen for discharge. Because institutional regulations typically limit EDOU stays to 24 hours, patients lacking a clinical response within this period will often be subsequently admitted to the hospital for further treatment.

Objective

The aim of this study was to determine the rate of hospital admission and characteristics predictive of admission in patients with cellulitis who are initially placed in an ED observation unit.

Methods

A retrospective cohort study of patients placed into EDOU with a diagnosis of skin infection was conducted. Age, sex, history of diabetes mellitus, immunosuppression, intravenous drug use, location of cellulitis, presence of abscess, laboratory infectious markers, vital signs, and outpatient antibiotic treatment were recorded. The primary outcome was a hospital admission due to failure to respond to treatment within the 24-hour observation time window. Significant variables on univariate analysis were used to create a multivariate analysis, which identified predictive characteristics.

Results

Four hundred six patient charts were reviewed, with 377 meeting inclusion criteria; the inpatient admission rate from EDOU was 29.2%. Using logistic regression techniques, we created a model of independent predictors for need of admission after 24 hours: cellulitis of the hand (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.8-4.9), measured temperature higher than 100.4°F (OR, 2.5; 95% CI, 1.1-5.5), and lactate greater than 2 (OR, 3.1; 95% CI, 1.3-7.3) were predictive of failure of ED observation.

Conclusions

Patients with cellulitis placed into ED observation status were more likely to fail an observation trial if they had an objective fever in the ED, an elevated lactate, or a cellulitis that involved the hand.     

ED evaluation of the pediatric trauma patient by ultrasonography

The purpose of this study was to determine the accuracy of ultrasound examination of pediatric trauma patients by emergency physicians. Pediatric (age less than 18 years) trauma patients presenting to the emergency department of a level I trauma center were prospectively examined with bedside ultrasound during the secondary survey of their trauma resuscitation. Examinations were performed by emergency medicine residents and attending physicians who had completed an 8-hour course on trauma ultrasonography. Trauma physicians providing care to the patient were blinded to the results of the examination. In 47 children (median age 9 years) computed tomography of the abdomen/pelvis or laparotomy were also performed and served as gold standards to verify the presence or absence of free fluid in the abdomen. Sensitivity, specificity, and accuracy of the ultrasound examination for the detection of free fluid in the abdominal cavity was 75% (95% confidence interval [CI] 36% to 95%), 97% (95% CI 81% to 100%), and 92% (95% Cl 77% to 98%). Positive and negative predictive values were 90% (95% CI 46% to 100%) and 92% (95% CI 74% to 99%), respectively. Ultrasound examinations took an average of 7 minutes and 36 seconds, although this did not take into consideration delays created by interruptions for other diagnostic tests or procedures. An emergency physician and radiologist agreed on blinded interpretations of 83% of the examinations (kappa = 0.56). Bedside ultrasonography is a reliable and rapid method for screening traumatized children for the presence or absence of free fluid in the peritoneum even in the hands of novice sonographers.     

An evaluation of emergency physician selection of observation unit patients

OBJECTIVE: Appropriate patient selection is critical for maximal observation unit (OU) effectiveness. We hypothesized emergency physicians underuse the OU for admitted patients and overuse the OU for patients who would otherwise be discharged. METHODS: Treating emergency physicians were asked about patient suitability for admission to an OU at a busy, urban, academic emergency department (ED) as part of a prospective cohort study of ED patients who were admitted or had an ED length of stay exceeding 4 hours. The OU was closed for renovation during the 2-month study, so physician opinion could be compared with patient course in the absence of observation services. Two blinded emergency physicians reviewed charts using structured forms and explicit definitions to determine actual patient course. Hospitalized patients were considered potential OU candidates according to a priori criteria: (1) hospital length of stay less than 48 hours, (2) no procedure or diagnosis requiring hospitalization, and (3) no death. RESULTS: Of 1747 enrolled patients, 131 were excluded with incomplete data. Median age was 45 years. Patients were 40% white and 48% men. Emergency physicians identified 363 (23%) patients as observation candidates. Of these, 182 (50%) were actually discharged directly. The remaining 181 (50%) were hospitalized; 101 (56%) were observation candidates based on chart review. Of 799 admitted patients not selected for observation, 232 (29%) were suitable for observation by chart review. CONCLUSIONS: Selection of patients for observation was suboptimal; emergency physicians routinely identified patients as OU candidates who were not ultimately admitted, and they missed many admitted patients who might have been appropriate OU candidates. Both over- and underuse should be addressed to maximize the effectiveness of OUs.     

Airway management of adult patients without trauma in an ED led by internists

Background

Airway management is a key competence in emergency medicine. Patients heavily differ from those in the operating room. They are acutely ill by definition and usually not fasting. Evaluation of risk factors is often impossible. Current literature primarily originates from countries where emergency medicine is an independent specialty. We evaluated intubations in a high-volume emergency department run by internists and comprising its own distinctive intensive care unit.

Methods

In this prospective, noncontrolled, observational study, we continuously documented all intubations performed at the emergency department. We analyzed demographic, medical, and staff-related factors predicting difficulties during intubation using logistic regression models.

Results

For 73 months, 660 cases were included, 69 (10.5%) of them were without any induction therapy. Two hundred fifty-two (38.2%) patients were female, and their mean age was 59 ± 17 years. Three hundred four (49.9%) had an initial Glasgow Coma Scale of 3. Leading indications were respiratory insufficiency (n = 246; 37.3%), resuscitation (n = 172; 26.1%), and intracranial hemorrhage (n = 75; 11.4%). First attempt was successful in 465 cases (75.1%); alternative airway devices were used in 22 cases (3.3%). Time from the first intubation attempt to a validated airway was 1 minute (interquartile range, 0-2 minutes). Physicians' experience and anatomical risk factors were associated with failure at the first attempt, prolonged intubation, and the need for alternative devices.

Conclusions

Airway management at the emergency department possesses a high potential of failure. Experience seems to be the key to success.     

Identification of chest pain patients appropriate for an emergency department observation unit

There are no perfect tests or algorithms to exclude ACI. Because acute coronary occlusion often occurs in patients with low-grade coronary stenosis, the diagnostic goal of a chest pain diagnostic protocol is not to identify patients with CAD, but rather to identify patients who may be safely discharged home without the development of complications such as MI, unstable angina, death, shock, or CHF over the next 1 to 6 months. There is an advantage to evaluating patients at the time of their symptoms. Patients who have a small plaque that is ruptured, leading to intracoronary thrombosis and ischemia, will manifest ischemia on diagnostic testing that could missed in routine outpatient testing when their plaque were stable. The diagnosis and risk stratification of acute coronary ischemia in the ED depends on a careful history and interpretation of the ECG. Multiple regression models using readily available data (e.g., history, physical examination, and ECG) provide the best tools for risk stratification. If one is deciding how to select patients for an EDOU chest pain evaluation, diagnostic tools that have previously been tested and validated in this setting are preferable. These include the Multicenter Chest Pain Study derived tools (i.e., Goldman, Lee), the ACI and ACI-TIPI tools, and sestamibi risk stratification tools. This is not to say that other tools may not play a role at individual institutions. It is probably better to select a consistent approach and evaluate its performance, rather than to allow random variation to dictate practice. The future direction probably will involve standardization of the ED chest pain population. This allows outcome and cost-effectiveness comparative research of various strategies for patients with normal or nondiagnostic ECGs and normal biomarkers. Although this approach allows more precise stratification, the risk will never be zero, meaning that there will never be a substitute for good clinical judgment and close follow-up care.