Dustin W. Ballard

Immediate and Delayed Traumatic Intracranial Hemorrhage in Patients With Head Trauma and Preinjury Warfarin or Clopidogrel Use

STUDY OBJECTIVE Patients receiving warfarin or clopidogrel are considered at increased risk for traumatic intracranial hemorrhage after blunt head trauma. The prevalence of immediate traumatic intracranial hemorrhage and the cumulative incidence of delayed traumatic intracranial hemorrhage in these patients, however, are unknown. The objective of this study is to address these gaps in knowledge. METHODS A prospective, observational study at 2 trauma centers and 4 community hospitals enrolled emergency department (ED) patients with blunt head trauma and preinjury warfarin or clopidogrel use from April 2009 through January 2011. Patients were followed for 2 weeks. The prevalence of immediate traumatic intracranial hemorrhage and the cumulative incidence of delayed traumatic intracranial hemorrhage were calculated from patients who received initial cranial computed tomography (CT) in the ED. Delayed traumatic intracranial hemorrhage was defined as traumatic intracranial hemorrhage within 2 weeks after an initially normal CT scan result and in the absence of repeated head trauma. RESULTS A total of 1,064 patients were enrolled (768 warfarin patients [72.2%] and 296 clopidogrel patients [27.8%]). There were 364 patients (34.2%) from Level I or II trauma centers and 700 patients (65.8%) from community hospitals. One thousand patients received a cranial CT scan in the ED. Both warfarin and clopidogrel groups had similar demographic and clinical characteristics, although concomitant aspirin use was more prevalent among patients receiving clopidogrel. The prevalence of immediate traumatic intracranial hemorrhage was higher in patients receiving clopidogrel (33/276, 12.0%; 95% confidence interval [CI] 8.4% to 16.4%) than patients receiving warfarin (37/724, 5.1%; 95% CI 3.6% to 7.0%), relative risk 2.31 (95% CI 1.48 to 3.63). Delayed traumatic intracranial hemorrhage was identified in 4 of 687 (0.6%; 95% CI 0.2% to 1.5%) patients receiving warfarin and 0 of 243 (0%; 95% CI 0% to 1.5%) patients receiving clopidogrel. CONCLUSION Although there may be unmeasured confounders that limit intergroup comparison, patients receiving clopidogrel have a significantly higher prevalence of immediate traumatic intracranial hemorrhage compared with patients receiving warfarin. Delayed traumatic intracranial hemorrhage is rare and occurred only in patients receiving warfarin. Discharging patients receiving anticoagulant or antiplatelet medications from the ED after a normal cranial CT scan result is reasonable, but appropriate instructions are required because delayed traumatic intracranial hemorrhage may occur.

Validation of an Algorithm for Categorizing the Severity of Hospital Emergency Department Visits

Background:Differentiating between appropriate and inappropriate resource use represents a critical challenge in health services research. The New York University Emergency Department (NYU ED) visit severity algorithm attempts to classify visits to the ED based on diagnosis, but it has not been formally validated. Objective:To assess the validity of the NYU algorithm. Research Design:A longitudinal study in a single integrated delivery system from January 1999 to December 2001. Subjects:A total of 2,257,445 commercial and 261,091 Medicare members of an integrated delivery system. Measures:ED visits were classified as emergent, nonemergent, or intermediate severity, using the NYU ED algorithm. We examined the relationship between visit-severity and the probability of future hospitalizations and death using a logistic model with a general estimating equation approach. Results:Among commercially insured subjects, ED visits categorized as emergent were significantly more likely to result in a hospitalization within 1-day (odds ratio = 3.37, 95% CI: 3.31–3.44) or death within 30-days (odds ratio = 2.81, 95% CI: 2.62–3.00) than visits categorized as nonemergent. We found similar results in Medicare patients and in sensitivity analyses using different probability thresholds. ED overuse for nonemergent conditions was not related to socio-economic status or insurance type. Conclusions:The evidence presented supports the validity of the NYU ED visit severity algorithm for differentiating ED visits based on need for hospitalization and/or mortality risk; therefore, it can contribute to evidence-based policies aimed at reducing the use of the ED for nonemergencies.

Informing the design of clinical decision support services for evaluation of children with minor blunt head trauma in the emergency department

Integration of clinical decision support services (CDSS) into electronic health records (EHRs) may be integral to widespread dissemination and use of clinical prediction rules in the emergency department (ED). However, the best way to design such services to maximize their usefulness in such a complex setting is poorly understood. We conducted a multi-site cross-sectional qualitative study whose aim was to describe the sociotechnical environment in the ED to inform the design of a CDSS intervention to implement the Pediatric Emergency Care Applied Research Network (PECARN) clinical prediction rules for children with minor blunt head trauma. Informed by a sociotechnical model consisting of eight dimensions, we conducted focus groups, individual interviews and workflow observations in 11 EDs, of which 5 were located in academic medical centers and 6 were in community hospitals. A total of 126 ED clinicians, information technology specialists, and administrators participated. We clustered data into 19 categories of sociotechnical factors through a process of thematic analysis and subsequently organized the categories into a sociotechnical matrix consisting of three high-level sociotechnical dimensions (workflow and communication, organizational factors, human factors) and three themes (interdisciplinary assessment processes, clinical practices related to prediction rules, EHR as a decision support tool). Design challenges that emerged from the analysis included the need to use structured data fields to support data capture and re-use while maintaining efficient care processes, supporting interdisciplinary communication, and facilitating family-clinician interaction for decision-making.

Risk of Traumatic Intracranial Hemorrhage in Patients with Head Injury and Preinjury Warfarin or Clopidogrel Use

OBJECTIVES Appropriate use of cranial computed tomography (CT) scanning in patients with mild blunt head trauma and preinjury anticoagulant or antiplatelet use is unknown. The objectives of this study were: 1) to identify risk factors for immediate traumatic intracranial hemorrhage (tICH) in patients with mild head trauma and preinjury warfarin or clopidogrel use and 2) to derive a clinical prediction rule to identify patients at low risk for immediate tICH. METHODS This was a prospective, observational study at two trauma centers and four community hospitals that enrolled adult emergency department (ED) patients with mild blunt head trauma (initial ED Glasgow Coma Scale [GCS] score 13 to 15) and preinjury warfarin or clopidogrel use. The primary outcome measure was immediate tICH, defined as the presence of ICH or contusion on the initial cranial CT. Risk for immediate tICH was analyzed in 11 independent predictor variables. Clinical prediction rules were derived with both binary recursive partitioning and multivariable logistic regression. RESULTS A total of 982 patients with a mean (± standard deviation [SD]) age of 75.4 (±12.6) years were included in the analysis. Sixty patients (6.1%; 95% confidence interval [CI] = 4.7% to 7.8%) had immediate tICH. History of vomiting (relative risk [RR] = 3.53; 95% CI = 1.80 to 6.94), abnormal mental status (RR = 2.85; 95% CI = 1.65 to 4.92), clopidogrel use (RR = 2.52; 95% CI = 1.55 to 4.10), and headache (RR = 1.81; 95% CI = 1.11 to 2.96) were associated with an increased risk for immediate tICH. Both binary recursive partitioning and multivariable logistic regression were unable to derive a clinical prediction model that identified a subset of patients at low risk for immediate tICH. CONCLUSIONS While several risk factors for immediate tICH were identified, the authors were unable to identify a subset of patients with mild head trauma and preinjury warfarin or clopidogrel use who are at low risk for immediate tICH. Thus, the recommendation is for urgent and liberal cranial CT imaging in this patient population, even in the absence of clinical findings.

Emergency Physicians’ Knowledge and Attitudes of Clinical Decision Support in the Electronic Health Record: A Survey‐based Study

OBJECTIVES The objective was to investigate clinician knowledge of and attitudes toward clinical decision support (CDS) and its incorporation into the electronic health record (EHR). METHODS This was an electronic survey of emergency physicians (EPs) within an integrated health care delivery system that uses a complete EHR. Randomly assigned respondents completed one of two questionnaires, both including a hypothetical vignette and self-reported knowledge of and attitudes about CDS. One vignette version included CDS, and the other did not (NCDS). The vignette described a scenario in which a cranial computed tomography (CCT) is not recommended by validated prediction rules (the Pediatric Emergency Care Applied Research Network [PECARN] rules). In both survey versions, subjects responded first with their likely approach to evaluation and then again after receiving either CDS (the PECARN prediction rules) or no additional support. Descriptive statistics were used for self-reported responses and multivariate logistic regression was used to identify predictors of self-reported knowledge and use of the PECARN rules, as well as use of vignette responses. RESULTS There were 339 respondents (68% response rate), with 172 of 339 (51%) randomized to the CDS version. Initially, 25% of respondents to each version indicated they would order CCTs. After CDS, 30 of 43 (70%) of respondents who initially would order CCTs changed their management decisions to no CCT versus two of 41 (5%) with the NCDS version (chi-square, p = 0.003). In response to self-report questions, 81 of 338 respondents (24%) reported having never heard of the PECARN prediction rules, 122 of 338 (36%) were aware of the rules but not their specifics, and 135 of 338 (40%) reported knowing the rules and their specifics. Respondents agreed with favorable statements about CDS (75% to 96% agreement across seven statements) and approaches to its implementation into the EHR (60% to 93% agreement across seven statements). In multivariable analyses, EPs with tenure of 5 to 14 years (odds ratio [AOR] = 0.51, 95% confidence interval [CI] = 0.30 to 0.86) and for 15 years or more (AOR = 0.37, 95% CI = 0.20 to 0.70) were significantly less likely to report knowing the specifics of the PECARN prediction rules compared with EPs who practiced for fewer than 5 years. In addition, in the initial vignette responses (across both versions), physicians with ≥15 years of ED tenure compared to those with fewer than 5 years of experience (AOR = 0.30, 95% CI = 0.13 to 0.69), and those reporting knowing the specifics of the PECARN prediction rules were less likely to order CCTs (AOR = 0.53, 95% CI = 0.30 to 0.92). CONCLUSIONS EPs incorporated pediatric head trauma CDS via the EHR into their clinical judgment in a hypothetical scenario and reported favorable opinions of CDS in general and their inclusion into the EHR.

Bleeding complications of central venous catheterization in septic patients with abnormal hemostasis.

OBJECTIVES Central venous catheterization (CVC) is thought to be relatively contraindicated in patients with thrombocytopenia or coagulopathy. We measured the 24-hour incidence of bleeding in septic emergency department (ED) patients undergoing CVC. METHODS This multicenter, retrospective cohort study included septic ED patients undergoing CVC with one of the following: platelets less than 100,000/μL, international normalized ratio at least 1.3, or partial thromboplastin time at least 35 seconds. Major bleeding included radiographically confirmed intrathoracic, mediastinal, or internal neck hemorrhage or line-related bleeding causing hemodynamic compromise. Minor bleeding included local oozing or superficial hematoma. Multivariable regression analysis was performed to determine the association between candidate variables and hemorrhagic complications. RESULTS Of the 936 cases, mean age was 68.1 years; 535 (57.2%) were male. Two or more qualifying laboratory abnormalities were present in 204 cases (21.8%). The proceduralists were predominately attendings (790; 84.4%). The initial veins were the internal jugular (n = 800; 85.5%), subclavian (n = 123; 13.1%), and femoral (n = 13; 1.4%). Initial access was successful in 872 cases (93.2%). We found one case (95% upper confidence limit: 0.6%) of major bleeding and 37 cases (4.0%; 95% confidence interval [CI], 2.8%-5.4%) of minor bleeding. Only failed access at the initial site was independently associated with hemorrhagic outcomes: adjusted odds ratio 8.2 (95% CI, 3.7-18.0). CONCLUSIONS Major bleeding from CVC in ED patients with abnormal hemostasis is rare. Minor bleeding is uncommon and infrequently requires intervention. Successful catheterization on the initial attempt is associated with fewer hemorrhagic complications. These results can inform the risk/benefit calculus for CVC in this population.

Pneumothorax is a rare complication of thoracic central venous catheterization in community EDs

STUDY OBJECTIVES The rate of iatrogenic pneumothorax associated with thoracic central venous catheterization in community emergency departments (EDs) is poorly described, although such information is vital to inform the procedures risk/benefit analysis. We undertook this multicenter study to estimate the incidence of immediate catheter-related pneumothorax in community EDs and to determine associations with site of access, failed access, and positive pressure ventilation. METHODS This was a secondary analysis of 2 retrospective cohort studies of adults who underwent attempted thoracic central venous catheterization in 1 of 21 EDs. Pneumothorax was identified by postprocedural anteroposterior chest radiograph or emergent evacuation for presumed tension pneumothorax. Frequencies were compared using Fishers exact test. RESULTS Among 1249 patient encounters, the initial vein of catheterization was internal jugular in 1054 cases (84.4%) and subclavian in 195 cases (15.6%). Success at the initial internal jugular vein was more common than at the initial subclavian vein (95.4% vs 83.6%, P < .001). Periprocedural positive pressure ventilation was administered in 316 patients (25.3%). We identified 6 pneumothoraces (0.5%; 95% confidence interval, 0.2%-1.1%). The incidence of pneumothorax was higher with the subclavian vein than the internal jugular vein (2.3% vs 0.1%, P < .001), with failed access at the initial vein (2.5% vs 0.3%, P = .05), and among patients receiving positive pressure ventilation (1.6% vs 0.1%, P < .01). CONCLUSION The incidence of pneumothorax from thoracic central venous catheterization in community EDs is low. The risk of pneumothorax is higher with a subclavian vein approach, failed access at the initial vein, and positive pressure ventilation.

In-hospital mortality following treatment with red blood cell transfusion or inotropic therapy during early goal-directed therapy for septic shock: a retrospective propensity-adjusted analysis

IntroductionWe sought to investigate whether treatment of subnormal (<70%) central venous oxygen saturation (ScvO2) with inotropes or red blood cell (RBC) transfusion during early goal-directed therapy (EGDT) for septic shock is independently associated with in-hospital mortality.MethodsRetrospective analysis of a prospective EGDT patient database drawn from 21 emergency departments with a single standardized EGDT protocol. Patients were included if, during EGDT, they concomitantly achieved a central venous pressure (CVP) of ≥8 mm Hg and a mean arterial pressure (MAP) of ≥65 mm Hg while registering a ScvO2 < 70%. Treatment propensity scores for either RBC transfusion or inotrope administration were separately determined from independent patient sub-cohorts. Propensity-adjusted logistic regression analyses were conducted to test for associations between treatments and in-hospital mortality.ResultsOf 2,595 EGDT patients, 572 (22.0%) met study inclusion criteria. The overall in-hospital mortality rate was 20.5%. Inotropes or RBC transfusions were administered for an ScvO2 < 70% to 51.9% of patients. Patients were not statistically more likely to achieve an ScvO2 of ≥70% if they were treated with RBC transfusion alone (29/59, 49.2%, P = 0.19), inotropic therapy alone (104/226, 46.0%, P = 0.15) or both RBC and inotropic therapy (7/12, 58.3%, P = 0.23) as compared to no therapy (108/275, 39.3%). Following adjustment for treatment propensity score, RBC transfusion was associated with a decreased adjusted odds ratio (aOR) of in-hospital mortality among patients with hemoglobin values less than 10 g/dL (aOR 0.42, 95% CI 0.18 to 0.97, P = 0.04) while inotropic therapy was not associated with in-hospital mortality among patients with hemoglobin values of 10 g/dL or greater (aOR 1.16, 95% CI 0.69 to 1.96, P = 0.57).ConclusionsAmong patients with septic shock treated with EGDT in the setting of subnormal ScvO2 values despite meeting CVP and MAP target goals, treatment with RBC transfusion may be independently associated with decreased in-hospital mortality.

The Use of Delayed Telephone Informed Consent for Observational Emergency Medicine Research Is Ethical and Effective

OBJECTIVES The objective was to describe the rate of successful consent using an altered (deferred telephone) consent process in emergency department (ED) patients. METHODS This study evaluated the consent process employed during a prospective, multicenter, observational study of outcomes in anticoagulated patients with blunt head trauma. The study was approved by the institutional review boards (IRBs) at all participating centers. Patients were not informed of the study during their enrollment at their index ED visit. Patient names, clinical findings, and contact information were collected at the time of initial ED visits. The patients or their legally designated surrogates were contacted by telephone at least 14 days after ED discharge, given all the elements of informed consent, and then consented for study participation. Study results are presented with simple descriptive statistics. RESULTS A total of 506 patients with a mean (±SD) age of 75.8 (±12.2) years including 274 female subjects (54.2%; 95% confidence interval [CI] = 49.7% to 58.6%) were enrolled into the study. Patients or their surrogates were successfully contacted by telephone in 501 of 506 cases (99.0%; 95% CI = 97.7% to 99.7%). Consent was obtained in 500 of 501 cases at time of telephone follow-up (99.8%; 95% CI = 98.9% to 100.0%). Surrogates provided consent in 199 cases (39.7%; 95% CI = 35.4% to 44.2%). Median time from ED visit to phone contact was 21 days (interquartile range [IQR] = 17 to 27 days). The median number of phone attempts for successful contact was 1 (IQR = 1 to 2 attempts). CONCLUSIONS The authors achieved a very high rate of successful telephone follow-up in this predominantly older ED population. Obtaining consent to participate in a research study using a deferred telephone contact process was effective and well received by both subjects and surrogates. IRBs should consider deferred telephone consent for minimal-risk studies requiring telephone follow-up, as opposed to a consent process requiring written documentation at the time of initial ED visit.

Risk stratifying emergency department patients with acute pulmonary embolism: Does the simplified Pulmonary Embolism Severity Index perform as well as the original?

INTRODUCTION The Pulmonary Embolism Severity Index (PESI) is a validated prognostic score to estimate the 30-day mortality of emergency department (ED) patients with acute pulmonary embolism (PE). A simplified version (sPESI) was derived but has not been as well studied in the U.S. We sought to validate both indices in a community hospital setting in the U.S. and compare their performance in predicting 30-day all-cause mortality and classification of cases into low-risk and higher-risk categories. MATERIALS AND METHODS This retrospective cohort study included adults with acute objectively confirmed PE from 1/2013 to 4/2015 across 21 community EDs. We evaluated the misclassification rate of the sPESI compared with the PESI. We assessed accuracy of both indices with regard to 30-day mortality. RESULTS Among 3006 cases of acute PE, the 30-day all-cause mortality rate was 4.4%. The sPESI performed as well as the PESI in identifying low-risk patients: both had similar sensitivities, negative predictive values, and negative likelihood ratios. The sPESI, however, classified a smaller proportion of patients as low risk than the PESI (27.5% vs. 41.0%), but with similar low-risk mortality rates (<1%). Compared with the PESI, the sPESI overclassified 443 low-risk patients (14.7%) as higher risk, yet their 30-day mortality was 0.7%. The sPESI underclassified 100 higher-risk patients (3.3%) as low risk who also had a low mortality rate (1.0%). CONCLUSIONS Both indices identified patients with PE who were at low risk for 30-day mortality. The sPESI, however, misclassified a significant number of low-mortality patients as higher risk, which could lead to unnecessary hospitalizations.