The association between advanced diagnostic imaging and ED length of stay

Impact of Spatial Separation for Respiratory Patients on Emergency Department Flow Process Intervals and Length of Stay

BACKGROUND

Spatial separation in emergency departments (ED) is empirically practised as part of transmission-based precaution. Despite its potential benefits in segregating potentially infectious patients, the effects of spatial separation on patient flow remains uncertain.

AIM

To explore the impact of spatial separation on ED patient flow and identify specific clinical factors and flow process intervals (FPI) influencing ED length-of-stay (EDLOS).

METHODS

This was a retrospective study of data extracted from patients' electronic medical records from January 1 to March 31, 2022 conducted at the ED of a tertiary hospital in Kuala Lumpur, Malaysia. During this period, patients were separated into respiratory areas (RA) and non-respiratory areas (NRA) based on Centers for Disease Control and Prevention recommendations. The study obtained ethics approval from the institution's ethics board.

FINDINGS

A total of 1,054 patients were included in the study, 275 allocated to RA and 779 to NRA. Patients in RA had a significantly longer median EDLOS compared to in NRA (9 hours 29 minutes versus 7 hours 6 minutes, p<0.001, d=0.41). A lower proportion of patients in RA achieved an EDLOS ≤8 hours compared to NRA (41.8% versus 58.3%, p<0.001). Independent factors affecting EDLOS were triage category, re-triaging, hypertension, performing biomedical imaging, medical, surgical, and critical care consultations, and disposition plan. Bottlenecks significantly prolonging EDLOS were decision-to-departure, ultrasound interval and referral-to-consultation.

CONCLUSION

Spatial separation prolongs FPI and EDLOS. Addressing inpatient access block and streamlining specialty review and biomedical imaging processes may reduce RA EDLOS.

The utility of the abdominal series in the emergency setting: a retrospective review

PURPOSE

The abdominal series (AXR) remains a frequently ordered test in the emergency department (ED), despite existing literature questioning its utility. The aim of this study was to characterize the use of the AXR in the ED by quantifying how often it is ordered and the frequency of subsequent imaging. Additionally, a time estimate in ED associated with the AXR was quantified. We hypothesized that there would be a low clinical utility of the AXR, and long associated time period spent in the ED.

METHODS

A retrospective audit of AXRs performed in the ED from January to December 2019 was performed. The local picture archiving and communication system (PACS) and electronic medical record were used to collect the variables.

RESULTS

Of 701 AXRs, 438 (62.4%) were reported normal, and 263 (37.6%) were abnormal. A Chi Squared test showed that the two variables (abdominal series result and follow up imaging completion) were significantly related, with p < 0.001. However, the effect size was small (Nagelkerke R square = 0.022). The average time spent in the ED for these patients was 7.27 h, and the average time between the AXR being ordered and interpreted was 1.31 h.

CONCLUSION

The majority of AXRs were reported as normal. Our results showed that AXR had a statistically significant, but low clinically significant predictive ability on subsequent imaging ordering. This supports our hypothesis that the AXR is of low clinical utility with respect to the rate of ordering follow up imaging. The AXR also translated to a quantifiable time interval during the patient's stay in ED. Minimizing overuse of the AXR may result in a decrease in patient duration in the ED.

The "NUTS" statistic: Applying an EBM disease model to defensive medicine

Physicians believe that malpractice concerns result in unnecessary testing, and many emergency physicians state that avoiding malpractice is a contributing factor to ordering medically unnecessary tests. Unfortunately, defensive medicine does not come without possible harm to patients who may be subject to non-beneficial, downstream testing, procedures, and hospitalizations. We submit a novel statistic, "NUTS" or "Number of Unnecessary Tests to avoid one Suit. " We calculated a NUTS of 4737 for troponin testing in ED patients with suspected myocardial infarction, meaning a clinician will need to order 4737 medically unnecessary troponin tests to avoid one missed myocardial infarction lawsuit. The NUTS framework offers us an evidence-based lens to examine defensive medicine less superstitiously and more based on currently available data.

Physicians' Risk Tolerance and Head Computed Tomography Use for Pediatric Patients With Minor Head Injury

OBJECTIVES

Traumatic brain injury is the leading cause of death and disability in children worldwide. The objective of this study was to determine the association between physician risk tolerance and head computed tomography (CT) use in patients with minor head injury (MHI) in the emergency department (ED).

METHODS

We retrospectively analyzed pediatric patients (<17 years old) with MHI in the ED and then administered 2 questionnaires (a risk-taking subscale [RTS] of the Jackson Personality Inventory and a malpractice fear scale [MFS]) to attending physicians who had evaluated these patients and made decisions regarding head CT use. The primary outcome was head CT use during ED evaluation; the secondary outcome was ED length of stay and final diagnosis of intracranial injury (ICI).

RESULTS

Of 523 patients with MHI, 233 (44.6%) underwent brain CT, and 16 (3.1%) received a final diagnosis of ICI. Among the 16 emergency physicians (EPs), the median scores of the MFS and RTS were 22 (interquartile range, 17-26) and 23 (interquartile range, 19-25), respectively. Emergency physicians who were most risk averse tended to order more head CT scans compared with the more risk-tolerant EPs (56.96% vs 37.37%; odds ratio, 8.463; confidence interval, 2.783-25.736). The ED length of stay (P = 0.442 and P = 0.889) and final diagnosis (P = 0.155 and P = 0.835) of ICI were not significantly associated with the RTS and MFS scores.

CONCLUSIONS

Individual EP risk tolerance, as measured by RTS, was predictive of CT use in pediatric patients with MHI.

Increasing and disparate use of neuroimaging for adults and children with non-traumatic headaches in the US emergency departments: Opportunities for improvement

BACKGROUND

Optimization of neuroimaging practices for headache is considered a national priority; however, nationwide patterns and predictors of neuroimaging use for headache in the US emergency departments (EDs) are unknown.

OBJECTIVE

To analyze temporal neuroimaging utilization trends for adults and children with non-traumatic headache in the US EDs and identify factors predictive of neuroimaging use in this patient population.

METHODS

Retrospective cross-sectional study using the Healthcare Cost and Utilization Project Nationwide Emergency Department Sample database for administrative encounter-level data analysis of a nationwide group of adult and pediatric patients with primary diagnosis of headache (ICD-9CM codes 784.0x, 339.xx, 346.xx) visited the US EDs between January 1, 2006 and December 31, 2014. Temporal trends and independent predictors of neuroimaging use (e.g., patient and hospital characteristics, primary payment sources) were determined.

RESULTS

In 2006-2014, a weighted group of 18,146,302 patients with a primary diagnosis of non-traumatic headache visited US EDs. Advanced neuroimaging utilization increased from 18.6% (n = 350,777) to 34.8% (n = 756,895) in the total group, from 18.8% (n = 314,646) to 36.5% (n = 698,080) in the adult subgroup (+94.1%), and from 16.9% (n = 36,131) to 22.0% (n = 58,815) (+30.2%) in the pediatric subgroup (+87.0%) between 2006 and 2014. The strongest predictors of higher neuroimaging utilization were hospital location in the Northeast (OR 3.17, 95% CI 2.67-3.76) or South (OR 2.42, 95% CI 2.03-2.88) regions. Lower utilization of imaging was associated with weekend ED visits (OR 0.92, 95% CI 0.92-0.93), female gender (OR 0.82, 95% CI 0.81-0.83), and Medicare, Medicaid, or self-pay (vs. private insurance) encounters.

CONCLUSION

Neuroimaging utilization in patients with headache in US EDs nearly doubled in 2006-2014, and was used in 34.8% of all ED encounters in 2014. Utilization was higher and increased at faster rates for adults than children. In US EDs, imaging for headache is preferentially performed on commercially insured and male patients, at urban hospitals, in certain geographic regions, and on weekdays, raising concerns regarding disparate imaging use.

Healthcare Resource Utilization of Ceftolozane/Tazobactam Versus Meropenem for Ventilated Nosocomial Pneumonia from the Randomized, Controlled, Double-Blind ASPECT-NP Trial

Introduction

Hospital-acquired and ventilator-associated bacterial pneumonia (HABP and VABP) are associated with significant healthcare resource utilization (HCRU). This a priori, exploratory, secondary analysis from the ASPECT-NP clinical trial evaluated resource utilization among patients with ventilated HABP (vHABP)/VABP treated with ceftolozane/tazobactam or meropenem.

Methods

This analysis used data from the randomized, double-blind, noninferiority phase 3 ASPECT-NP trial of patients with vHABP/VABP randomized to receive ceftolozane/tazobactam 3 g (ceftolozane 2 g/tazobactam 1 g) or meropenem 1 g for 8–14 days. Day 28 outcomes included hospital length of stay (LOS), intensive care unit (ICU) LOS, and time to mechanical ventilation extubation in the microbiological intention-to-treat (mITT) population and in an HCRU population. The HCRU population, a subset of patients from the mITT population that were alive at day 28, was used to remove resource use bias influenced by mortality rates.

Results

Ceftolozane/tazobactam-treated versus meropenem-treated patients, respectively, had fewer deaths (20.1% vs. 25.5%), fewer hospital discharges (30.7% vs. 32.4%), and higher ICU discharges (60.0% vs. 58.3%) and extubations (51.9% vs. 48.2%) by day 28. In the HCRU population, adjusted LOS differences (95% confidence intervals) for ceftolozane/tazobactam compared with meropenem were 0.1 (− 1.4 to 1.6) hospitalization days, − 1.4 (− 2.9 to 0.2) ICU days, and − 0.9 (− 2.4 to 0.7) mechanical ventilation days. Patterns were similar among the VABP and Pseudomonas aeruginosa subgroups.

Conclusion

Similar 28-day resource utilization outcomes were observed between ceftolozane/tazobactam and meropenem in the mITT population of patients from ASPECT-NP with vHABP/VABP due to gram-negative pathogens. ASPECT-NP was not powered to detect differences in resource utilization outcomes between treatment groups; however, numerical differences in ICU LOS and duration of mechanical ventilation were noted. Further study is needed to assess resource utilization in the real-world practice setting, especially among patients excluded from ASPECT-NP, including those with resistant P. aeruginosa infections.

Trial Registrations

ClinicalTrials.gov: NCT02070757, registered February 25, 2014; EudraCT: 2012-002862-11.

Electronic supplementary material

The online version of this article (10.1007/s40121-020-00343-0) contains supplementary material, which is available to authorized users.

Diagnostic Performance of Emergency Physician Gestalt for Predicting Acute Appendicitis in Patients Age 5 to 20 Years

OBJECTIVES

Pediatric appendicitis remains a challenging diagnosis in the emergency department (ED). Available risk prediction algorithms may contribute to excessive ED imaging studies. Incorporation of physician gestalt assessment could help refine predictive tools and improve diagnostic imaging decisions.

METHODS

This study was a subanalysis of a parent study that prospectively enrolled patients ages 5 to 20.9 years with a chief complaint of abdominal pain presenting to 11 community EDs within an integrated delivery system between October 1, 2016, and September 30, 2018. Prior to diagnostic imaging, attending emergency physicians enrolled patients with ≤5 days of right-sided or diffuse abdominal pain using a Web-based application embedded in the electronic health record. Predicted risk (gestalt) of acute appendicitis was prospectively entered using a sliding scale from 1% to 100%. As a planned secondary analysis, we assessed the performance of gestalt via c-statistics of receiver operating characteristic (ROC) curves; tested associations between gestalt performance and patient, physician, and facility characteristics; and examined clinical characteristics affecting gestalt estimates.

RESULTS

Of 3,426 patients, 334 (9.8%) had confirmed appendicitis. Physician gestalt had excellent ROC curve characteristics (c-statistic = 0.83, 95% confidence interval = 0.81 to 0.85), performing particularly well in the low-risk strata (appendicitis rate = 1.1% in gestalt 1%-10% range, negative predictive value of 98.9% for appendicitis diagnosis). Physicians with ≥5 years since medical school graduation demonstrated improved gestalt performance over those with less experience (p = 0.007). All clinical characteristics tested, except pain <24 hours, were significantly associated with physician gestalt value (p < 0.05).

CONCLUSION

Physician gestalt for acute appendicitis diagnosis performed well, especially in low-risk patients and when employed by experienced physicians.

Influence of emergency department patient volumes on CT utilization rate of the physician in triage

BACKGROUND

Physician in triage (PIT) has been used as a potential solution to emergency department (ED) overcrowding and to decrease ED length of stay (LOS). This study examined the relationship between computerized tomography (CT) utilization of PIT and ED patient volumes. We hypothesized that despite the pressure on PIT to improve throughput on the busiest days, they will continue to utilize CT at the same rate.

METHODS

This retrospective chart review evaluated CT ordering patterns of PIT on patients with abdominal pain who presented to the ED over a 6-year period. CT utilization rate was calculated on days with the lowest 5% (LD5) and highest 5% (HD5) volumes based on average yearly volume. CT positive and negative rates were correlated with volume using Chi square analysis. Odds ratio and confidence intervals were calculated for the magnitude of effect difference.

RESULTS

We found no statistically significant difference in CT utilization rate on HD5 vs LD5 (p = 0.833). There was a statistically significant increase in the rate of negative CT scans on HD5 (p = 0.046) which represented a 17% relative difference. LOS was longer on HD5 (p = 0.013) and when a CT scan was ordered (p < 0.001).

CONCLUSION

No difference was found in the rate at which the PIT ordered CT scans on high volume vs low volume days. The rate of CT scans without clinically relevant findings did increase slightly on high volume days. LOS was longer on high volume days and when a CT was ordered.

Use of natural language processing to improve predictive models for imaging utilization in children presenting to the emergency department

OBJECTIVE

To examine the association between the medical imaging utilization and information related to patients' socioeconomic, demographic and clinical factors during the patients' ED visits; and to develop predictive models using these associated factors including natural language elements to predict the medical imaging utilization at pediatric ED.

METHODS

Pediatric patients' data from the 2012-2016 United States National Hospital Ambulatory Medical Care Survey was included to build the models to predict the use of imaging in children presenting to the ED. Multivariable logistic regression models were built with structured variables such as temperature, heart rate, age, and unstructured variables such as reason for visit, free text nursing notes and combined data available at triage. NLP techniques were used to extract information from the unstructured data.

RESULTS

Of the 27,665 pediatric ED visits included in the study, 8394 (30.3%) received medical imaging in the ED, including 6922 (25.0%) who had an X-ray and 1367 (4.9%) who had a computed tomography (CT) scan. In the predictive model including only structured variables, the c-statistic was 0.71 (95% CI: 0.70-0.71) for any imaging use, 0.69 (95% CI: 0.68-0.70) for X-ray, and 0.77 (95% CI: 0.76-0.78) for CT. Models including only unstructured information had c-statistics of 0.81 (95% CI: 0.81-0.82) for any imaging use, 0.82 (95% CI: 0.82-0.83) for X-ray, and 0.85 (95% CI: 0.83-0.86) for CT scans. When both structured variables and free text variables were included, the c-statistics reached 0.82 (95% CI: 0.82-0.83) for any imaging use, 0.83 (95% CI: 0.83-0.84) for X-ray, and 0.87 (95% CI: 0.86-0.88) for CT.

CONCLUSIONS

Both CT and X-rays are commonly used in the pediatric ED with one third of the visits receiving at least one. Patients' socioeconomic, demographic and clinical factors presented at ED triage period were associated with the medical imaging utilization. Predictive models combining structured and unstructured variables available at triage performed better than models using structured or unstructured variables alone, suggesting the potential for use of NLP in determining resource utilization.

The use of a dedicated neurological triage system improves process times and resource utilization: a prospective observational study from an interdisciplinary emergency department

Background

Patients with neurological symptoms have been contributing to the increasing rates of emergency department (ED) utilization in recent years. Existing triage systems represent neurological symptoms rather crudely, neglecting subtler but relevant aspects like temporal evolution or associated symptoms. A designated neurological triage system could positively impact patient safety by identifying patients with urgent need for medical attention and prevent inadequate utilization of ED and hospital resources.

Methods

We compared basic demographic information, chief complaint/presenting symptom, door-to-doctor time and length of stay (LOS) as well as utilization of ED resources of patients presenting with neurological symptoms or complaints during a one-month period before as well as after the introduction of the Heidelberg Neurological Triage System (HEINTS) in our interdisciplinary ED. In a second step, we compared diagnostic and treatment processes for both time periods according to assigned acuity.

Results

During the two assessment periods, 299 and 300 patients were evaluated by a neurologist, respectively. While demographic features were similar for both groups, overall LOS (p < 0.001) was significantly shorter, while CT (p = 0.023), laboratory examinations (p = 0.006), ECG (p = 0.011) and consultations (p = 0.004) were performed significantly less often when assessing with HEINTS. When considering acuity, an epileptic seizure was less frequently evaluated as acute with HEINTS than in the pre-HEINTS phase (p = 0.002), while vertigo patients were significantly more often rated as acute with HEINTS (p < 0.001). In all cases rated as acute, door-to-doctor-time (DDT) decreased from 41.0 min to 17.7 min (p < 0.001), and treatment duration decreased from 304.3 min to 149.4 min (p < 0.001) after introduction of HEINTS triage.

Conclusion

A dedicated triage system for patients with neurological complaints reduces DDT, LOS and ED resource utilization, thereby improving ED diagnostic and treatment processes.

Urinary Stone Detection on CT Images Using Deep Convolutional Neural Networks: Evaluation of Model Performance and Generalization

Purpose

To investigate the diagnostic accuracy of cascading convolutional neural network (CNN) for urinary stone detection on unenhanced CT images and to evaluate the performance of pretrained models enriched with labeled CT images across different scanners.

Materials and Methods

This HIPAA-compliant, institutional review board-approved, retrospective clinical study used unenhanced abdominopelvic CT scans from 535 adults suspected of having urolithiasis. The scans were obtained on two scanners (scanner 1 [hereafter S1] and scanner 2 [hereafter S2]). A radiologist reviewed clinical reports and labeled cases for determination of reference standard. Stones were present on 279 (S1, 131; S2, 148) and absent on 256 (S1, 158; S2, 98) scans. One hundred scans (50 from each scanner) were randomly reserved as the test dataset, and the rest were used for developing a cascade of two CNNs: The first CNN identified the extent of the urinary tract, and the second CNN detected presence of stone. Nine variations of models were developed through the combination of different training data sources (S1, S2, or both [hereafter SB]) with (ImageNet, GrayNet) and without (Random) pretrained CNNs. First, models were compared for generalizability at the section level. Second, models were assessed by using area under the receiver operating characteristic curve (AUC) and accuracy at the patient level with test dataset from both scanners (n = 100).

Results

The GrayNet-pretrained model showed higher classifier exactness than did ImageNet-pretrained or Random-initialized models when tested by using data from the same or different scanners at section level. At the patient level, the AUC for stone detection was 0.92-0.95, depending on the model. Accuracy of GrayNet-SB (95%) was higher than that of ImageNet-SB (91%) and Random-SB (88%). For stones larger than 4 mm, all models showed similar performance (false-negative results: two of 34). For stones smaller than 4 mm, the number of false-negative results for GrayNet-SB, ImageNet-SB, and Random-SB were one of 16, three of 16, and five of 16, respectively. GrayNet-SB identified stones in all 22 test cases that had obstructive uropathy.

Conclusion

A cascading model of CNNs can detect urinary tract stones on unenhanced CT scans with a high accuracy (AUC, 0.954). Performance and generalization of CNNs across scanners can be enhanced by using transfer learning with datasets enriched with labeled medical images.© RSNA, 2019Supplemental material is available for this article. : An earlier incorrect version appeared online. This article was corrected on August 6, 2019.

Advanced diagnostic imaging utilization during emergency department visits in the United States: A predictive modeling study for emergency department triage

Background

Emergency department (ED) crowding is associated with negative health outcomes, patient dissatisfaction, and longer length of stay (LOS). The addition of advanced diagnostic imaging (ADI), namely CT, ultrasound (U/S), and MRI to ED encounter work up is a predictor of longer length of stay. Earlier and improved prediction of patients’ need for advanced imaging may improve overall ED efficiency. The aim of the study was to detect the association between ADI utilization and the structured and unstructured information immediately available during ED triage, and to develop and validate models to predict utilization of ADI during an ED encounter.

Methods

We used the United States National Hospital Ambulatory Medical Care Survey data from 2009 to 2014 to examine which sociodemographic and clinical factors immediately available at ED triage were associated with the utilization of CT, U/S, MRI, and multiple ADI during a patient’s ED stay. We used natural language processing (NLP) topic modeling to incorporate free-text reason for visit data available at time of ED triage in addition to other structured patient data to predict the use of ADI using multivariable logistic regression models.

Results

Among the 139,150 adult ED visits from a national probability sample of hospitals across the U.S, 21.9% resulted in ADI use, including 16.8% who had a CT, 3.6% who had an ultrasound, 0.4% who had an MRI, and 1.2% of the population who had multiple types of ADI. The c-statistic of the predictive models was greater than or equal to 0.78 for all imaging outcomes, and the addition of text-based reason for visit information improved the accuracy of all predictive models.

Conclusions

Patient information immediately available during ED triage can accurately predict the eventual use of advanced diagnostic imaging during an ED visit. Such models have the potential to be incorporated into the ED triage workflow in order to more rapidly identify patients who may require advanced imaging during their ED stay and assist with medical decision-making.

Factors associated with failure of emergency wait-time targets for high acuity discharges and intensive care unit admissions

Objective

Ontario established emergency department length-of-stay (EDLOS) targets but has difficulty achieving them. We sought to determine predictors of target time failure for discharged high acuity patients and intensive care unit (ICU) admissions.

Methods

This was a retrospective, observational study of 2012 Sunnybrook Hospital emergency department data. The main outcome measure was failing to meet government EDLOS targets for high acuity discharges and ICU emergency admissions. The secondary outcome measures examined factors for low acuity discharges and all admissions, as well as a run chart for 2015 – 2016 ICU admissions. Multiple logistic regression models were created for admissions, ICU admissions, and low and high acuity discharges. Predictor variables were at the patient level from emergency department registries.

Results

For discharged high acuity patients, factors predicting EDLOS target failure were having physician initial assessment duration (PIAD)>2 hours (OR 5.63 [5.22-6.06]), consultation request (OR 10.23 [9.38-11.14]), magnetic resonance imaging (MRI) (OR 19.33 [12.94-28.87]), computed tomography (CT) (OR 4.24 [3.92-4.59]), and ultrasound (US) (OR 3.47 [3.13-3.83]). For ICU admissions, factors predicting EDLOS target failure were bed request duration (BRD)>6 hours (OR 364.27 [43.20-3071.30]) and access block (AB)>1 hour (OR 217.27 [30.62-1541.63]). For discharged low acuity patients, factors predicting failure for the 4-hour target were PIAD>2 hours (OR 15.80 [13.35-18.71]), consultation (OR 20.98 [14.10-31.22]), MRI (OR 31.68 [6.03-166.54]), CT (OR 16.48 [10.07-26.98]), and troponin I (OR 13.37 [6.30-28.37]).

Conclusion

Sunnybrook factors predicting failure of targets for high acuity discharges and ICU admissions were hospital-controlled. Hospitals should individualize their approach to shortening EDLOS by analysing its patient population and resource demands.

Utility of computed tomographic imaging of the cervical spine in trauma evaluation of ground-level fall

BACKGROUND

Computed tomography (CT) of the cervical spine (C-spine) is routinely ordered for low-risk mechanisms of injury, including ground-level fall. Two commonly used clinical decision rules (CDRs) to guide C-spine imaging in trauma are the National Emergency X-Radiography Utilization Study (NEXUS) and the Canadian Cervical Spine Rule for Radiography (CCR).

METHODS

Retrospective cross-sectional study of 3,753 consecutive adult patients presenting to an urban Level I emergency department who received C-spine CT scans were obtained over a 6-month period. The primary outcome of interest was prevalence of C-spine fracture. Secondary outcomes included fracture stability, appropriateness of imaging by NEXUS and CCR criteria, and estimated radiation dose exposure and costs associated with C-spine imaging studies.

RESULTS

Of the 760 patients meeting inclusion criteria, 7 C-spine fractures were identified (0.92% ± 0.68%). All fractures were identified by NEXUS and CCR criteria with 100% sensitivity. Of all these imaging studies performed, only 69% met NEXUS indications for imaging (50% met CCR indications). C-spine CT scans in patients not meeting CDR indications were associated with costs of $15,500 to $22,000 by NEXUS ($14,600-$25,600 by CCR) in this single center during the 6-month study period.

CONCLUSION

For ground-level fall, C-spine CT is overused. The consistent application of CDR criteria would reduce annual nationwide imaging costs in the United States by $6.8 to $9.6 million based on NEXUS ($6.4-$15.6 million based on CCR) and would reduce population radiation dose exposure by 0.8 to 1.1 million mGy based on NEXUS (0.7-1.9 million mGy based on CCR) if applied across all Level I trauma centers. Greater use of evidence-based CDRs plays an important role in facilitating emergency department patient management and reducing systemwide radiation dose exposure and imaging expenditures.

LEVEL OF EVIDENCE

Diagnostic study, level III.

Do delays in radiology lead to breaches in the 4-hour rule?

AIM

To assess trends in medical imaging requests before and after the 4-hour rule commenced and to assess the imaging time component of emergency department (ED) length of stay (LOS).

MATERIALS AND METHODS

Retrospective analysis of ED patients and imaging requests 1 year prior to and 3 years after implementation of the 4-hour rule (April to December for 2011-2014) was performed at a single adult tertiary referral Level 1 trauma hospital with Level 6 ED. Logistic regression was used to evaluate trends in the number of ED patient presentations, patient triage categories, and imaging requests for these patients. The imaging component of the total ED LOS was compared for patients who met the 4-hour target and patients who did not.

RESULTS

Compared to 2011 (before the 4-hour rule), ED presentations increased 4.74% in 2012, 12.7% in 2013, 21.28% in 2014 (p<0.01). Total imaging requests increased 23.05% in 2012, 48.04% in 2013, 60.77% in 2014 (p<0.01). For patients breaching the 4-hour rule, the mean time before radiology request was 2.4-2.8 hours; mean time from imaging request to completion was 1.2-1.3 hours; mean time from imaging completion to discharge from ED was the longest component of ED LOS (4.9-5.9 hours).

CONCLUSIONS

There has been a significant increase in imaging requests, with a trend towards more CT and less radiography requests. Imaging requests for patients who breached the 4-hour target were made on average 2.4-2.8 hours after triage and average time after imaging in itself, exceeded 4 hours. Imaging is not likely a causative factor for patients breaching the 4-hour target.

Acute Abdomen in the Emergency Department: Is CT a Time-Limiting Factor?

OBJECTIVE

The purpose of this study was to quantify and integrate key emergency department (ED) and radiology department workflow time intervals within the ED length of stay (LOS) for patients presenting with acute abdomen who require CT.

MATERIALS AND METHODS

An 11-month retrospective review was performed of all patients presenting to the ED with an acute abdomen who required abdominal CT. Nine key time points associated with ED LOS and CT workflow were collected: triage, physician assessment, CT request, porter schedule, CT start, CT complete, provision of first CT report, ED disposition decision, and physical discharge. The median and 90th percentile times for each interval were reported.

RESULTS

Ninety-six percent (2194/2292) of ED encounters during the study period met the inclusion criteria. The median ED LOS was 9.22 hours (90th percentile, 15.7 hours). Intervals associated with CT workflow accounted for 29% of the total LOS. Radiology turnaround time accounted for 32% of the entire CT workflow interval. Timeline analysis found three unique patterns of ED disposition: disposition after initial imaging report, disposition before report, and disposition before CT.

CONCLUSION

To our knowledge, this study is the first to quantify the contribution of CT-related workflow time intervals within the context of ED LOS. We have shown that patients do not have identical ED transit pathways, and this may under- or overestimate time interval calculations. These results show the importance of site-specific ED LOS timeline analysis to identify potential targets for quality improvement and serve as baseline targets for measuring future quality improvement initiatives.

Overtesting and the Downstream Consequences of Overtreatment: Implications of "Preventing Overdiagnosis" for Emergency Medicine

Overtesting, the downstream consequences of overdiagnosis, and overtreatment of some patients are topics of growing debate within emergency medicine (EM). The "Preventing Overdiagnosis" conference, hosted by The Dartmouth Institute for Health Policy and Clinical Practice, with sponsorship from consumer organizations, medical journals, and academic institutions, is evidence of an expanding interest in this topic. However, EM represents a compellingly unique environment, with increased decision density tied to high stakes for patients and providers with missed or delayed diagnoses in a professional atmosphere that does not tolerate mistakes. This article reviews the relevance of this reductionist paradigm to EM, provides a first-hand synopsis of the first "Preventing Overdiagnosis" conference, and assesses barriers to moving the concept of less test ordering to reality.

The use of model-based iterative reconstruction to decrease ED radiation exposure

INTRODUCTION

The radiation risk posed by diagnostic computed tomography (CT) is a growing concern. The use of model-based iterative reconstruction (MBIR) technology reduces radiation exposure but requires additional processing time. The goal of this study was to compare MBIR and a standard CT reconstructive protocols in terms of emergency department (ED) visit duration and reduction in radiation exposure.

METHODS

A retrospective, matched, case-control design was used to compare patients who received MBIR and standard protocol abdomen and pelvis CTs. ED length of stay (LOS) and radiation exposure were the 2 primary outcome variables.

RESULTS

During the study period, 121 patients met inclusion criteria and were matched to controls for a total of 242 subjects. Although the low-dose group LOS was slightly longer, there was no significant difference in LOS. Mean differences were 18 minutes overall (520 vs 502 minutes; P = .497), 11 minutes for admitted patients (587 vs 576 minutes; P = .839), and 22 minutes for discharged patients (490 vs 468 minutes; P = .482). The mean volume CT dose index for the standard-dose CT was 11.6 ± 8.3 and 7.7 ± 4.6 mGy for the reduced-dose CT, a 34% decrease (P < .001).

CONCLUSION

Use of MBIR in the ED may provide decreased radiation exposure while minimally impacting ED LOS.