Fever Incidence Is Much Lower in the Morning than the Evening: Boston and US National Triage Data.

INTRODUCTION: In this observational study, we evaluated time-of-day variation in the incidence of fever that is seen at triage. The observed incidence of fever could change greatly over the day because body temperatures generally rise and fall in a daily cycle, yet fever is identified using a temperature threshold that is unchanging, such as ≥38.0° Celsius (C) (≥100.4° Fahrenheit [F]). METHODS: We analyzed 93,225 triage temperature measurements from a Boston emergency department (ED) (2009-2012) and 264,617 triage temperature measurements from the National Hospital Ambulatory Medical Care Survey (NHAMCS, 2002-2010), making this the largest study of body temperature since the mid-1800s. Boston data were investigated exploratorily, while NHAMCS was used to corroborate Boston findings and check whether they generalized. NHAMCS results are nationally representative of United States EDs. Analyses focused on adults. RESULTS: In the Boston ED, the proportion of patients with triage temperatures in the fever range (≥38.0°C, ≥100.4°F) increased 2.5-fold from morning to evening (7:00-8:59 PM vs 7:00-8:59 AM: risk ratio [RR] 2.5, 95% confidence interval [CI], 2.0-3.3). Similar time-of-day changes were observed when investigating alternative definitions of fever: temperatures ≥39.0°C (≥102.2°F) and ≥40.0°C (≥104.0°F) increased 2.4- and 3.6-fold from morning to evening (7:00-8:59 PM vs 7:00-8:59 AM: RRs [95% CIs] 2.4 [1.5-4.3] and 3.6 [1.5-17.7], respectively). Analyses of adult NHAMCS patients provided confirmation, showing mostly similar increases for the same fever definitions and times of day (RRs [95% CIs] 1.8 [1.6-2.1], 1.9 [1.4-2.5], and 2.8 [0.8-9.3], respectively), including after adjusting for 12 potential confounders using multivariable regression (adjusted RRs [95% CIs] 1.8 [1.5-2.1], 1.8 [1.3-2.4], and 2.7 [0.8-9.2], respectively), in age-group analyses (18-64 vs 65+ years), and in several sensitivity analyses. The patterns observed for fever mirror the circadian rhythm of body temperature, which reaches its highest and lowest points at similar times. CONCLUSION: Fever incidence is lower at morning triages than at evening triages. High fevers are especially rare at morning triage and may warrant special consideration for this reason. Studies should examine whether fever-causing diseases are missed or underappreciated during mornings, especially for sepsis cases and during screenings for infectious disease outbreaks. The daily cycling of fever incidence may result from the circadian rhythm.

The daily, weekly, and seasonal cycles of body temperature analyzed at large scale.

We performed large-scale analyses of circadian and infradian cycles of human body temperature, focusing on changes over the day, week, and year. Temperatures (n= 93,225) were collected using temporal artery thermometers from a Boston emergency department during 2009-2012 and were statistically analyzed using regression with cyclic splines. The overall mean body temperature was 36.7°C (98.1°F), with a 95% confidence interval of 36.7-36.7°C (98.1-98.1°F) and a standard deviation of 0.6°C (1.1°F). Over the day, mean body temperature followed a steady cycle, reaching its minimum at 6:00-8:00 and its maximum at 18:00-20:00. Across days of the week, this diurnal cycle was essentially unchanged, even though activities and sleeping hours change substantially during the weekly cycles of human behavior. Over the year, body temperatures were slightly colder in winter than summer (~0.2°C difference), consistent with most prior studies. We propose these seasonal differences might be due to ambient effects on body temperature that are not eliminated because they fall within the tolerance range of the thermoregulatory system. Over the year, bathyphase (daily time of minimum temperature) appeared to parallel sunrise times, as expected from sunrise's zeitgeber role in circadian rhythms. However, orthophase (daily time of maximum temperature) and sunset times followed opposite seasonal patterns, with orthophase preceding nightfall in summer and following nightfall in winter. Throughout the year, bathyphase and orthophase remained separated by approximately 12 h, suggesting this interval might be conserved. Finally, although 37.0°C (98.6°F) is widely recognized as the mean or normal human body temperature, analysis showed mean temperature was <37.0°C during all times of day, days of the week, and seasons of the year, supporting prior arguments that the 37.0°C standard has no scientific basis. Overall, this large study showed robust and consistent behavior of the human circadian cycle at the population level, providing a strong example of circadian homeostasis.

A unique case of bradycardia recognized by wearable technology as first presentation of complete heart block.

Wearable technology has advanced significantly, and the proposed health benefits have been widely touted. Most of the discussion has been surrounding the identification and diagnosis of asymptomatic atrial fibrillation. However, the heart monitoring functions of the wearable technology can also identify other abnormalities as well. We present the first case of wearable technology identified bradycardia diagnosed as the primary presentation of complete heart block. Wearable technology has advanced significantly, but still poses questions regarding its use in screening for rare conditions. One remaining challenge is balancing the desire to screen for rare asymptomatic conditions without overburdening emergency departments with patients responding to alarms on their devices.

Human temperatures for syndromic surveillance in the emergency department: data from the autumn wave of the 2009 swine flu (H1N1) pandemic and a seasonal influenza outbreak.

BACKGROUND: The emergency department (ED) increasingly acts as a gateway to the evaluation and treatment of acute illnesses. Consequently, it has also become a key testing ground for systems that monitor and identify outbreaks of disease. Here, we describe a new technology that automatically collects body temperatures during triage. The technology was tested in an ED as an approach to monitoring diseases that cause fever, such as seasonal flu and some pandemics. METHODS: Temporal artery thermometers that log temperature measurements were placed in a Boston ED and used for initial triage vital signs. Time-stamped measurements were collected from the thermometers to investigate the performance a real-time system would offer. The data were summarized in terms of rates of fever (temperatures ≥100.4 °F [≥38.0 °C]) and were qualitatively compared with regional disease surveillance programs in Massachusetts. RESULTS: From September 2009 through August 2011, 71,865 body temperatures were collected and included in our analysis, 2073 (2.6 %) of which were fevers. The period of study included the autumn-winter wave of the 2009-2010 H1N1 (swine flu) pandemic, during which the weekly incidence of fever reached a maximum of 5.6 %, as well as the 2010-2011 seasonal flu outbreak, during which the maximum weekly incidence of fever was 6.6 %. The periods of peak fever rates corresponded with the periods of regionally elevated flu activity. CONCLUSIONS: Temperature measurements were monitored at triage in the ED over a period of 2 years. The resulting data showed promise as a potential surveillance tool for febrile disease that could complement current disease surveillance systems. Because temperature can easily be measured by non-experts, it might also be suitable for monitoring febrile disease activity in schools, workplaces, and transportation hubs, where many traditional syndromic indicators are impractical. However, the system's validity and generalizability should be evaluated in additional years and settings.

Evaluating the effect of emergency residency training on productivity in the emergency department.

BACKGROUND: Resident productivity, defined as patients seen per unit time, is one measure that is used to assess the performance and educational progress of residents in the emergency department (ED). One published study suggested that emergency residency training (EM) does not improve productivity compared with that in other specialties, including internal medicine (IM). OBJECTIVES: This study assesses how EM and IM trainees perform in the ED and illustrates how resident productivity changes through the academic year. METHODS: A retrospective review of attending physicians and residents working 8-h shifts in the higher acuity zone of a large-volume, tertiary, academic health care center was performed for July 2009, October 2009, January 2010, and April 2010. The total number of patients seen primarily and admitted during each shift was recorded. ED volume was approximated by the number of patients seen by the attending physician, and acuity was approximated by admission rate. A mixed model regression assessed the impact of year and type of residency training (e.g., EM1, EM2, IM1, and IM2), ED volume, and acuity on resident productivity (number of patients per shift). The study was granted waiver of informed consent by our institutional review board. RESULTS: We reviewed 936 shifts. After adjusting for acuity and ED volume, the EM1 group had a significant increase in patients per shift over the year, from 6.11 in July to 10.3 in April (p < 0.001). No other group increased productivity significantly. CONCLUSIONS: The first EM training year leads to a significant change in productivity that separates EM from IM residents. This contradicts the previous assertion that non-EM residents have the same productivity as EM residents in the ED.

Eliminating routine oral contrast use for CT in the emergency department: impact on patient throughput and diagnosis.

This study aimed to assess the effect of eliminating routine oral contrast use for abdominopelvic (AP) computed tomography (CT) on emergency department (ED) patient throughput and diagnosis. Retrospective analysis was performed on patients undergoing AP CT during 2-month periods prior to and following oral contrast protocol change in an urban, tertiary care ED. Patients with inflammatory bowel disease, prior gastrointestinal tract-altering surgery, or lean body habitus continued to receive oral contrast. Oral contrast was otherwise eliminated from the AP CT protocol. Patients were excluded if they would not have typically received oral contrast, regardless of the intervention. Data recorded include patient demographics, ED length of stay (LOS), time from order to CT, 72-h ED return, and repeat imaging. Two thousand and one ED patients (1,014 before and 987 after protocol change) underwent AP CT during the study period. Six hundred seven pre-intervention and 611 post-intervention were eligible for oral contrast and included. Of these, 95 % received oral contrast prior to the intervention and 42 % thereafter. After the intervention, mean ED LOS among oral contrast eligible patients decreased by 97 min, P < 0.001. Mean time from order to CT decreased by 66 min, P < 0.001. No patient with CT negative for acute findings had additional subsequent AP imaging within 72 h at our institution that led to a change in diagnosis. Eliminating routine oral contrast use for AP CT in the ED may be successful in decreasing LOS and time from order to CT without demonstrated compromise in acute patient diagnosis.

Creatine kinase-MB does not add additional benefit to a negative troponin in the evaluation of chest pain.

OBJECTIVE: The aim of this study was to determine whether current troponin assay alone can be used for initial screening for acute myocardial infarction (AMI) and whether creatine kinase-MB (CK-MB) can safely be eliminated from this evaluation in the emergency department (ED). METHODS: A retrospective cohort study of patients who had cardiac troponin T (Roche, Basel, Switzerland) and CK-MB ordered at an urban academic level 1 trauma center with more than 55,000 annual visits. Patients with troponin testing in the ED were identified over a period of 12 months, and corresponding CK-MB indexes were examined identifying patients with negative troponins (<0.01) and positive CK-MB indexes (>6.0). In these patients, further cardiac markers, hospital course, and 30-day mortality were then evaluated. A 99% confidence interval around point estimate was used in data analysis. RESULTS: During the study period, there were 11,092 separate ED patient encounters where a patient had at least one troponin resulted. Most (97.9%) of the samples had an associated CK-MB ordered. There were 7545 initial negative troponins representing 68% of all initial samples. Seven of these had an associated positive MB index. When subsequent troponins were evaluated, an additional 4910 negative troponins were identified, with 4 patients having a positive MB. None of these 11 patients were judged to have ruled in for AMI by the treating physicians. The rate of true-positive CK-MB index with negative troponin was 0% (99% confidence interval, 0-0.04%). CONCLUSION: Our results suggest that CK-MB is not necessary in the initial screening for AMI and may safely be omitted in patients with negative troponins.

Should creatine kinase-MB index be eliminated in patients with indeterminate troponins in the ED?

OBJECTIVES: The objective of this study is to determine whether creatine kinase-MB (CK-MB) index (CK-MBi) is useful in the evaluation of acute myocardial infarction (AMI) in patients with indeterminate troponin (Tn) in the emergency department (ED). METHODS: A retrospective cohort study was conducted of patients at an urban academic ED with over 55 000 annual visits who underwent Tn T (Roche, Indianapolis, IN) and CK-MB testing. One year of ED patients who had Tn testing were identified, and their corresponding CK-MBi was examined to find patients with indeterminate Tn (0.01-0.09) and positive CK-MBi (>6.0). Subsequent cardiac enzymes and hospital course were reviewed to identify patients diagnosed with AMI. A 95% confidence interval around point estimates were used in data analysis. RESULTS: Over 1 year, 11 718 initial Tn were identified. Indeterminate Tn was seen in 2512 cases. Of these, 28 had positive CK-MBi. Of the 28, 5 were judged by treating physicians to be having AMI and underwent cardiac catheterization. Of the 5 patients, 4 had subsequent positive Tns on serial enzyme testing. One of the patients thought to be having AMI had no coronary artery disease on catheterization. The rate of true positive CK-MBi with indeterminate Tn was 0.16% (95% confidence interval, 0.04%-0.41%). CONCLUSION: Initial results identify rare cases of AMI where CK-MBi is positive in the setting of indeterminate Tn. However, most patients with indeterminate Tn and positive CK-MBi were not judged to be having AMI. In most cases, CK-MBi is not positive with indeterminate Tn and when positive more commonly confuses the picture. This suggests CK-MBi could be eliminated in patients with indeterminate Tns.

Emergency department abnormal vital sign "triggers" program improves time to therapy.

BACKGROUND: Implementation of rapid response systems to identify deteriorating patients in the inpatient setting has demonstrated improved patient outcomes. A "trigger" system using vital sign abnormalities to initiate evaluation by physician was recently described as an effective rapid response method. OBJECTIVES: The objective was to evaluate the effect of a triage-based trigger system on the primary outcome of time to physician evaluation and the secondary outcomes of therapeutic intervention, antibiotics, and disposition in emergency department (ED) patients. METHODS: A separate-samples pre- and postintervention study was conducted using retrospective chart review of outcomes in ED patients for three arbitrarily selected 5-day periods in 2007 (pretriggers) and 2008 (posttriggers). There were 2,165 and 2,212 charts in the pre- and posttriggers chart review, with 71 and 79 patients meeting trigger criteria. Trigger criteria used to identify patients at triage were: heart rate of <40 or >130 beats/min, respiratory rate of <8 or >30 breaths/min, systolic blood pressure of <90 mm Hg, and oxygen saturation of <90% on room air. Median times (in minutes) were compared between pre- and posttrigger groups with interquartile ranges (IQRs 25-75), with the Wilcoxon rank sum test used to determine statistical significance. RESULTS: Overall median times were decreased among the posttriggers group. Median times to physician evaluation (21 minutes [IQR = 13-41 minutes] vs. 11 minutes [IQR = 5-21 minutes]; p < 0.001), first intervention (58 minutes [IQR = 20-139 minutes] vs. 26 minutes [IQR = 11-71 minutes]; p < 0.01), and antibiotics (110 minutes [IQR = 74-171 minutes] vs. 69 minutes [IQR = 23-130 minutes]; p < 0.01) were significant. Median times to disposition (177 minutes [IQR = 121-303 minutes] vs. 162 minutes [IQR = 114-230 minutes]; p = 0.18) were not significant. CONCLUSIONS: Implementation of an ED triggers program allows for more rapid time to physician evaluation, therapeutic intervention, and antibiotics.

Use of separate venipunctures for IV access and laboratory studies decreases hemolysis rates.

Emergency department (ED) patients routinely undergo placement of a saline lock device (SLD) with the aspiration of blood for laboratory testing. Drawing blood through a SLD may result in hemolysis of sample, repeated venipuncture and increased ED length of stay (LOS). The objective of this study was to examine if separate venipunctures for intravenous (IV) access and laboratory studies decrease the rate of hemolysis and ED LOS. The study was conducted at an urban university level 1 trauma center with an ED volume of 55,000. We compared the rate of hemolysis and ED LOS before and after mandating the use of separate venipunctures for IV access and laboratory studies over 1 month. Venipuncture was performed utilizing either a 21 ga needle or an IV catheter (BD Insight Autoguard) with a needless vacutainer. The incidence of hemolysis was calculated and a Student's t test was used to compare groups. The potassium sample redraw and processing time was observed. Blood was aspirated from 315 patients using the SLD. A baseline hemolysis rate of 23.0% (16.7-29.1) was obtained, corrected to 6.7% after factoring a 29.2% redraw rate for critical potassium levels. In the following month, 2,564 samples were obtained using the butterfly needle with a hemolysis rate of 6.6% (5.5-7.5), corrected to 2.0% after applying the 29.2% redraw rate. Avoiding hemolysis, we saved 4.7% of our patients' 56 min of ED stay, and avoided 185 retests over the month. In conclusion, venipuncture from a butterfly needle decreases the rate of hemolysis and may decrease the overall ED LOS.

Effect of two different FDA-approved D-dimer assays on resource utilization in the emergency department.

BACKGROUND: The D-dimer assay has been shown to be an appropriate test to rule out pulmonary embolism (PE) in low-risk patients in the emergency department (ED). Multiple assays now are approved to measure D-dimer levels. Studies have shown a newer assay, Tina-quant, to have similar diagnostic accuracy to the VIDAS assay. OBJECTIVES: The objective was to determine effects of transitioning from the VIDAS assay to the Tina-quant D-dimer assay on the need for computed tomography angiogram (CTA) and ED length of stay (LOS) in patients being evaluated for PE in the ED. METHODS: A retrospective cohort study was conducted of patients who had D-dimer levels ordered at an urban, academic, Level I trauma center with over 55,000 annual ED visits. The results of D-dimer levels in the ED were recorded over a period of 6 months prior to and 6 months after the transition to the new D-dimer assay. The numbers of positive and negative D-dimers and need for subsequent CTAs were recorded for comparison. LOS was also recorded to determine time saved. Medians were calculated and compared using Wilcoxon rank sum. RESULTS: During the initial period, 875 D-dimers were ordered, with a positive rate of 41.5%. During the period after the introduction of the Tina-quant assay, 859 tests were ordered, with 25.5% having positive results. An absolute decrease of 16% in the number of necessary CTAs (p < 0.003) was seen after the transition to the Tina-quant assay. LOS data showed a mean LOS of 481 minutes in the ED for patients who underwent testing with the Tina-quant assay compared to 526 minutes with the VIDAS assay, saving an average of 45 minutes per patient (p < 0.003). The positive rate on performed imaging studies for D-dimer of > 500 rose from 13 of 308 (4.2%) to 17 of 187 (9.1%). CONCLUSIONS: Switching D-dimer assays reduced both LOS and number of imaging studies in our patient population.

Klebsiella pneumoniae liver abscess: an emerging problem in North America.

BACKGROUND: Before the 1980s, Escherichia coli was the most common cause of pyogenic liver abscess, but more recently, Klebsiella pneumoniae has emerged as the most common organism in the United States and Taiwan. OBJECTIVE: Our goal is to present a case of K. pneumoniae liver abscess (KLA) and review the risk factors, presenting symptoms, complications, and treatment of this disease that is emerging in North America. CASE REPORT: We present a patient who was found to have KLA complicated by bacteremia and sepsis. CONCLUSIONS: Initially described in the Asian literature, KLA is an emerging problem in North America. We present this case to increase awareness among emergency physicians of the diagnosis, risk factors, potential complications-including bacteremia and disseminated infection-and treatment.

Isolated, spontaneous superior mesenteric and celiac artery dissection: case report and review of literature.

Spontaneous, isolated dissection of the superior mesenteric artery (SMA) and celiac artery (CA) is rare. Although there are known risk factors, there is no particular mechanism that is common to vascular dissections. The objectives of this study were to review the current literature on diagnosis and treatment of isolated SMA and CA dissection, and to review aortic complications in giant cell arteritis, Takayasu arteritis, and polyarteritis nodosa. Giant cell arteritis, Takayasu arteritis, and polyarterteritis nodosa are vasculitides that are associated with SMA and CA dissection. An interesting aspect of this case is that the patient was a healthy person before presentation, and ultimately, did not have an underlying etiology to explain the dissection. In addition, the patient was successfully managed without operative intervention. Although there are known risk factors in patients who present with isolated, spontaneous SMA and CA dissection, the pathogenesis is still unclear. The prognosis has improved significantly with the early use of computed tomography angiography to diagnosis this entity. Although most cases require surgical intervention, there are some, as in this case, that are managed non-operatively.

Eliminating amylase testing from the evaluation of pancreatitis in the emergency department.

BACKGROUND: Alterations in serum biomarkers have been used to evaluate for pancreatitis in the emergency department (ED). Studies have shown lipase to be as sensitive and more specific than amylase in diagnosing pancreatitis and that amylase plus lipase does not improve accuracy over lipase alone. OBJECTIVE: To determine effects of interventions to decrease ordering of amylase in the evaluation of pancreatitis. METHODS: We conducted a pre- and post-cohort study. The number of amylase and lipase tests ordered in the ED was recorded prior to intervention to establish a baseline. We introduced an educational intervention to order lipase without amylase. A second intervention involved removing amylase from bedside order entry forms. We introduced a third intervention that included deleting amylase from trauma order forms, and decoupling amylase and lipase in the computer ordering system. We recorded the number of lipase and amylase tests in weekly aggregates for comparison to the baseline. Data analysis using students t-test, standard deviation and p values are reported. RESULTS: Before interventions 93% of patients had both tests ordered. Educational interventions resulted in a decrease to 91% (p=0.06) of co-ordering. Further interventions decreased the percentage of patients evaluated with both tests to 14.3%. This translates into a decrease in patient charges of approximately $350,000 a year. CONCLUSION: Using simple structured interventions in the ED can reduce amylase ordering. Educational programming alone was not effective in significantly decreasing amylase ordering; however, education plus system-based interventions decreased amylase ordering.

Morbidity and Mortality conference in Emergency Medicine.

BACKGROUND: Morbidity and Mortality conferences (M&M) are used to meet many of the Core Competencies required by the Accreditation Council of Graduate Medical Education for residency training programs. This study seeks to describe and quantify different types of M&M conferences among Emergency Medicine (EM) training programs. METHODS: A confidential survey was e-mailed to the Program Directors (PD) or Assistant PD of all United States (US) Emergency Medicine residency training programs with functional e-mail addresses listed in the Society for Academic Emergency Medicine residency catalog. Descriptive statistics and 95% confidence (CI) intervals are reported. RESULTS: Of 124 surveys sent out, 89 (72%) completed surveys were returned. There were 88 programs (99%, CI 93-100%) that reported having an M&M. Conferences are held monthly at 67% (CI 57-76%) of programs. Cases for discussion are identified by an EM attending, quality assurance committee, or resident (70%, 57%, and 48%, respectively). Half of programs reported that > 40% of the cases involve systems errors. Twenty percent of programs report that > 40% of the cases involve deaths. Consultants are invited at 44% of programs, and 20% of programs specifically invite radiologists. If a medical error is identified in the M&M, 79% (70-86%) of programs have a protocol for addressing the error. CONCLUSION: EM training programs almost uniformly have an M&M, but these conferences vary in frequency, content, and attendance. Future studies are needed to investigate resident and faculty perceptions of M&M, its educational impact, and ways to improve the conference.