Blunt Head Injury in the Elderly: Analysis of the NEXUS II Injury Cohort.

BACKGROUND: Changes with aging make older patients vulnerable to blunt head trauma and alter the potential for injury and the injury patterns seen among this expanding cohort. High-quality care requires a clear understanding of the factors associated with blunt head injuries in the elderly. Our objective was to develop a detailed assessment of the injury mechanisms, presentations, injury patterns, and outcomes among older blunt head trauma patients. METHODS: We conducted a planned secondary analysis of patients aged 65 or greater who were enrolled in the National Emergency X-Radiography Utilization Study (NEXUS) Head Computed Tomography validation study. We performed a detailed assessment of the demographics, mechanisms, presentations, injuries, interventions, and outcomes among older patients. RESULTS: We identified 3,659 patients aged 65 years or greater, among the 11,770 patients enrolled in the NEXUS validation study. Of these older patients, 325 (8.9%) sustained significant injuries, as compared with significant injuries in 442 (5.4%) of the 8,111 younger patients. Older females (1,900; 51.9%) outnumbered older males (1,753; 47.9%), and occult presentations (exhibiting no high-risk clinical criteria beyond age) occurred in 48 (14.8%; 95% confidence interval (CI) 11.1 to 19.1) patients with significant injuries. Subdural hematomas (377 discreet lesions in 299 patients) and subarachnoid hemorrhages (333 discreet instances in 256 patients) were the most frequent types of injuries occurring in our elderly population. A ground-level fall was the most frequent mechanism of injury among all patients (2,211; 69.6%), those sustaining significant injuries (180; 55.7%), and those who died of their injuries (37; 46.3%), but mortality rates were highest among patients experiencing a fall from a ladder (11.8%; 4 deaths among 34 cases [95% CI 3.3% to 27.5%]) and automobile versus pedestrian events (10.7%; 16 deaths among 149 cases [95% CI 6.3% to 16.9%]). Among older patients who required neurosurgical intervention for their injuries, only 16.4% (95% CI 11.1% to 22.9%) were able to return home, 32.1% (95% CI 25.1% to 39.8%) required extended facility care, and 41.8% (95% CI 34.2% to 49.7%) died from their injuries. CONCLUSIONS: Older blunt head injury patients are at high risk of sustaining serious intracranial injuries even with low-risk mechanisms of injury, such as ground-level falls. Clinical evaluation is unreliable and frequently fails to identify patients with significant injuries. Outcomes, particularly after intervention, can be poor, with high rates of long-term disability and mortality.

Characteristics of Intracranial Injuries in Pediatric Patients Following Blunt Head Trauma.

OBJECTIVES: Pediatric head trauma is a frequent reason for presentation to the emergency department. Despite this, there are few reports on specific characteristics and injury patterns in head injured children. The goal of this study was to evaluate head injury patterns in children with blunt head injury and their prevalence by age group. METHODS: This is a planned secondary analysis of the NEXUS II Head CT validation study. Consecutive patients with blunt head trauma were enrolled between 2006 and 2015. Demographics and criteria from 2 clinical decision instruments (NEXUS and Canadian Head CT rules) were gathered at the time of enrollment. We abstracted and cataloged injuries for pediatric patients based on radiologist report. Frequencies of injuries and severity were analyzed by developmental age group. RESULTS: A total of 1018 pediatric patients were enrolled, 128 (12.6%) of whom had an injury on computed tomography scan. Median age was 11.9 (Interquartile range 4.5-15.5) for all patients and 12 (4.8-15.5) for injured patients. Of injured patients, 49 (38.3%) had a significant injury, and 27 (21.1%) received an intervention. Teenagers had the highest rate of significant injury (50%) and intervention (30%). Injuries were most frequently noted in the temporal (46.1%), frontal (45.3%), and parietal (45.3%) regions. Subarachnoid hemorrhage (29.7%) and subdural hematoma (28.9%) were the most common injuries observed.Intraparenchymal hemorrhage and cerebral edema were more prevalent in older age groups. The most common injury mechanism overall was fall from height (24.7%). Motor vehicle accidents and nonmotorized wheeled vehicle accidents were more common in older patients. CONCLUSIONS: Serious injuries requiring intervention were rarely encountered in pediatric patients experiencing blunt head trauma. Mechanisms of injury, type of injury, and rates of intervention varied between developmental age groups.

Acetaminophen for Prevention and Treatment of Organ Dysfunction in Critically Ill Patients With Sepsis: The ASTER Randomized Clinical Trial.

Importance: Acetaminophen (paracetamol) has many pharmacological effects that might be beneficial in sepsis, including inhibition of cell-free hemoglobin-induced oxidation of lipids and other substrates. Objective: To determine whether acetaminophen increases days alive and free of organ dysfunction in sepsis compared with placebo. Design, Setting, and Participants: Phase 2b randomized, double-blind, clinical trial conducted from October 2021 to April 2023 with 90-day follow-up. Adults with sepsis and respiratory or circulatory organ dysfunction were enrolled in the emergency department or intensive care unit of 40 US academic hospitals within 36 hours of presentation. Intervention: Patients were randomized to 1 g of acetaminophen intravenously every 6 hours or placebo for 5 days. Main Outcome and Measures: The primary end point was days alive and free of organ support (mechanical ventilation, vasopressors, and kidney replacement therapy) to day 28. Treatment effect modification was evaluated for acetaminophen by prerandomization plasma cell-free hemoglobin level higher than 10 mg/dL. Results: Of 447 patients enrolled (mean age, 64 [SD, 15] years, 51% female, mean Sequential Organ Failure Assessment [SOFA] score, 5.4 [SD, 2.5]), 227 were randomized to acetaminophen and 220 to placebo. Acetaminophen was safe with no difference in liver enzymes, hypotension, or fluid balance between treatment arms. Days alive and free of organ support to day 28 were not meaningfully different for acetaminophen (20.2 days; 95% CI, 18.8 to 21.6) vs placebo (19.6 days; 95% CI, 18.2 to 21.0; P = .56; difference, 0.6; 95% CI, -1.4 to 2.6). Among 15 secondary outcomes, total, respiratory, and coagulation SOFA scores were significantly lower on days 2 through 4 in the acetaminophen arm as was the rate of development of acute respiratory distress syndrome within 7 days (2.2% vs 8.5% acetaminophen vs placebo; P = .01; difference, -6.3; 95% CI, -10.8 to -1.8). There was no significant interaction between cell-free hemoglobin levels and acetaminophen. Conclusions and Relevance: Intravenous acetaminophen was safe but did not significantly improve days alive and free of organ support in critically ill sepsis patients. Trial Registration: ClinicalTrials.gov Identifier: NCT04291508.

Physical Examination Sensitivity for Skull Fracture in Pediatric Patients With Blunt Head Trauma: A Secondary Analysis of the National Emergency X-Radiography Utilization Study II Head Computed Tomography Validation Study.

STUDY OBJECTIVE: We evaluated the emergency department (ED) providers' ability to detect skull fractures in pediatric patients presenting with blunt head trauma. METHODS: This was a secondary analysis of the National Emergency X-Radiography Utilization Study (NEXUS) Head computed tomography (CT) validation study. Demographics and clinical characteristics were analyzed for pediatric patients. Radiologist interpretations of head CT imaging were abstracted and cataloged. Detection of skull fractures was evaluated through provider response to specific clinical decision instrument criteria (NEXUS or Canadian head CT rules) at the time of initial patient evaluation. The presence of skull fracture was determined by formal radiologist interpretation of CT imaging. RESULTS: Between April 2006, and December 2015, 1,018 pediatric patients were enrolled. One hundred twenty-eight (12.5%) children had a notable injury reported on CT head. Skull fracture was present in most (66.4%) children with intracranial injuries. The sensitivity and specificity of provider physical examination to detect skull fractures was 18.5% (95% confidence interval 10.5% to 28.7%) and 96.6% (95.3% to 97.7%), respectively. The most common injuries associated with skull fractures were subarachnoid hemorrhage (27%) and subdural hematoma (22.3%). CONCLUSION: Skull fracture is common in children with intracranial injury after blunt head trauma. Despite this, providers were found to have poor sensitivity for skull fractures in this population, and these injuries may be missed on initial emergency department assessment.

Prevalence of Intracranial Injury in Adult Patients With Blunt Head Trauma With and Without Anticoagulant or Antiplatelet Use.

STUDY OBJECTIVE: We determine the prevalence of significant intracranial injury among adults with blunt head trauma who are receiving preinjury anticoagulant or antiplatelet medications. METHODS: This was a multicenter, prospective, observational study conducted from December 2007 to December 2015. Patients were enrolled in 3 emergency departments (EDs) in the United States. Adults with blunt head trauma who underwent neuroimaging in the ED were included. Use of preinjury aspirin, clopidogrel, and warfarin was recorded. Data on direct oral anticoagulants were not specifically recorded. The primary outcome was prevalence of significant intracranial injury on neuroimaging. The secondary outcome was receipt of neurosurgical intervention. RESULTS: Among 9,070 patients enrolled in this study, the median age was 53.8 years (interquartile range 34.7 to 74.3 years) and 60.7% were men. A total of 1,323 patients (14.6%) were receiving antiplatelet medications or warfarin, including 635 receiving aspirin alone, 109 clopidogrel alone, and 406 warfarin alone. Compared with that of patients without any coagulopathy, the relative risk of significant intracranial injury was 1.29 (95% confidence interval [CI] 0.88 to 1.87) for patients receiving aspirin alone, 0.75 (95% CI 0.24 to 2.30) for those receiving clopidogrel alone, and 1.88 (95% CI 1.28 to 2.75) for those receiving warfarin alone. The relative risk of significant intracranial injury was 2.88 (95% CI 1.53 to 5.42) for patients receiving aspirin and clopidogrel in combination. CONCLUSION: Patients receiving preinjury warfarin or a combination of aspirin and clopidogrel were at increased risk for significant intracranial injury, but not those receiving aspirin alone. Clinicians should have a low threshold for neuroimaging when evaluating patients receiving warfarin or a combination of aspirin and clopidogrel.

Thoracic Spine Fracture in the Panscan Era.

STUDY OBJECTIVE: In the current era of frequent chest computed tomography (CT) for adult blunt trauma evaluation, many minor injuries are diagnosed, potentially rendering traditional teachings obsolete. We seek to update teachings in regard to thoracic spine fracture by determining how often such fractures are observed on CT only (ie, not visualized on preceding trauma chest radiograph), the admission rate, mortality, and hospital length of stay of thoracic spine fracture patients, and how often thoracic spine fractures are clinically significant. METHODS: This was a preplanned analysis of prospectively collected data from the NEXUS Chest CT study conducted from 2011 to 2014 at 9 Level I trauma centers. The inclusion criteria were older than 14 years, blunt trauma occurring within 6 hours of emergency department (ED) presentation, and chest imaging (radiography, CT, or both) during ED evaluation. RESULTS: Of 11,477 enrolled subjects, 217 (1.9%) had a thoracic spine fracture; 181 of the 198 thoracic spine fracture patients (91.4%) who had both chest radiograph and CT had their thoracic spine fracture observed on CT only. Half of patients (49.8%) had more than 1 level of thoracic spine fracture, with a mean of 2.1 levels (SD 1.6 levels) of thoracic spine involved. Most patients (62%) had associated thoracic injuries. Compared with patients without thoracic spine fracture, those with it had higher admission rates (88.5% versus 47.2%; difference 41.3%; 95% confidence interval 36.3% to 45%), higher mortality (6.3% versus 4.0%; difference 2.3%; 95% confidence interval 0 to 6.7%), and longer length of stay (median 9 versus 6 days; difference 3 days; P<.001). However, thoracic spine fracture patients without other thoracic injury had mortality similar to that of patients without thoracic spine fracture (4.6% versus 4%; difference 0.6%; 95% confidence interval -2.5% to 8.6%). Less than half of thoracic spine fractures (47.4%) were clinically significant: 40.8% of patients received thoracolumbosacral orthosis bracing, 10.9% had surgery, and 3.8% had an associated neurologic deficit. CONCLUSION: Thoracic spine fracture is uncommon. Most thoracic spine fractures are associated with other thoracic injuries, and mortality is more closely related to these other injuries than to the thoracic spine fracture itself. More than half of thoracic spine fractures are clinically insignificant; surgical intervention is uncommon and neurologic injury is rare.

Pneumothorax and Hemothorax in the Era of Frequent Chest Computed Tomography for the Evaluation of Adult Patients With Blunt Trauma.

STUDY OBJECTIVE: Although traditional teachings in regard to pneumothorax and hemothorax generally recommend chest tube placement and hospital admission, the increasing use of chest computed tomography (CT) in blunt trauma evaluation may detect more minor pneumothorax and hemothorax that might indicate a need to modify these traditional practices. We determine the incidence of pneumothorax and hemothorax observed on CT only and the incidence of isolated pneumothorax and hemothorax (pneumothorax and hemothorax occurring without other thoracic injuries), and describe the clinical implications of these injuries. METHODS: This was a planned secondary analysis of 2 prospective, observational studies of adult patients with blunt trauma, NEXUS Chest (January 2009 to December 2012) and NEXUS Chest CT (August 2011 to May 2014), set in 10 Level I US trauma centers. Participants' inclusion criteria were older than 14 years, presentation to the emergency department (ED) within 6 hours of blunt trauma, and receipt of chest imaging (chest radiograph, chest CT, or both) during their ED evaluation. Exposure(s) (for observational studies) were that patients had trauma and chest imaging. Primary measures and outcomes included the incidence of pneumothorax and hemothorax observed on CT only versus on both chest radiograph and chest CT, the incidence of isolated pneumothorax and hemothorax (pneumothorax and hemothorax occurring without other thoracic injuries), and admission rates, hospital length of stay, mortality, and frequency of chest tube placement for these injuries. RESULTS: Of 21,382 enrolled subjects, 1,064 (5%) had a pneumothorax and 384 (1.8%) had a hemothorax. Of the 8,661 patients who received both a chest radiograph and a chest CT, 910 (10.5%) had a pneumothorax, with 609 (67%) observed on CT only; 319 (3.7%) had a hemothorax, with 254 (80%) observed on CT only. Of 1,117 patients with pneumothorax, hemothorax, or both, 108 (10%) had isolated pneumothorax or hemothorax. Patients with pneumothorax observed on CT only had a lower chest tube placement rate (30% versus 65%; difference in proportions [Δ] -35%; 95% confidence interval [CI] -28% to 42%), admission rate (94% versus 99%; Δ 5%; 95% CI 3% to 8%), and median length of stay (5 versus 6 days; difference 1 day; 95% CI 0 to 2 days) but similar mortality compared with patients with pneumothorax observed on chest radiograph and CT. Patients with hemothorax observed on CT had only a lower chest tube placement rate (49% versus 68%; Δ -19%; 95% CI -31% to -5%) but similar admission rate, mortality, and median length of stay compared with patients with hemothorax observed on chest radiograph and CT. Compared with patients with other thoracic injury, those with isolated pneumothorax or hemothorax had a lower chest tube placement rate (20% versus 43%; Δ -22%; 95% CI -30% to -13%), median length of stay (4 versus 5 days; difference -1 day; 95% CI -3 to 1 days), and admission rate (44% versus 97%; Δ -53%; 95% CI -62% to -43%), with an admission rate comparable to that of patients without pneumothorax or hemothorax (49%). CONCLUSION: Under current imaging protocols for adult blunt trauma evaluation, most pneumothoraces and hemothoraces are observed on CT only and few occur as isolated thoracic injury. The clinical implications (admission rates and frequency of chest tube placement) of pneumothorax and hemothorax observed on CT only and isolated pneumothorax or hemothorax are lower than those of patients with pneumothorax and hemothorax observed on chest radiograph and CT and of those who have other thoracic injury, respectively.

Sensitivity of a bedside reagent strip for the detection of spontaneous bacterial peritonitis in ED patients with ascites.

STUDY OBJECTIVE: To determine the sensitivity of a highly sensitive bedside leukocyte esterase reagent strip (RS) for detection of spontaneous bacterial peritonitis (SBP) in emergency department (ED) ascites patients undergoing paracentesis. METHODS: We conducted a prospective, observational cohort study of ED ascites patients undergoing paracentesis at two academic facilities. Two practitioners, blinded to each other's results, did a bedside RS analysis of the peritoneal fluid in each patient and documented the RS reading at 3-min according to manufacturer-specified colorimetric strip reading as either "negative", "trace", "small", or "large". The primary outcome measure was sensitivity of the RS strip for SBP (absolute neutrophil count ≥ 250 cells/mm3) at the "trace" threshold (positive equals trace or greater). RESULTS: There were 330 cases enrolled, with 635 fluid analyses performed. Of these, 40 fluid samples had SBP (6%). Bedside RS had a sensitivity, specificity, positive predictive value, and negative predictive value of 95% (95% CI 82%-99%), 48% (95% CI 44%-52%), 11% (95% CI 10%-11%), and 99% (95% CI 97%-99%) respectively at the "trace" threshold for the detection of SBP. CONCLUSION: Bedside use of the RS in ED ascites patients demonstrated high sensitivity for SBP. Given the wide confidence intervals, we cannot currently recommend it as a stand-alone test. We recommend further study with a larger number of SBP patients, potentially combining a negative RS result with low clinical suspicion to effectively rule out SBP without formal laboratory analysis.

Selective Prereduction Radiography in Anterior Shoulder Dislocation: The Fresno-Quebec Rule.

BACKGROUND: Shoulder dislocation is one of the most frequent dislocations encountered by emergency physicians. Typical emergency care usually includes performing both prereduction and postreduction radiography. However, selective radiography has the potential benefits of reducing emergency department (ED) time and radiation exposure. OBJECTIVES: To refine and combine two existing clinical decision rules for selective radiography in the ED management of anterior shoulder dislocation, thus creating the Fresno-Quebec rule (FQR). METHODS: Patients presenting to the ED with an anterior shoulder dislocation were enrolled in a prospective cohort study in two university-affiliated EDs. Patients with a clinically important fracture-dislocation were compared with those with an uncomplicated dislocation. We refined our new decision rule to detect all fracture-dislocations while maximizing specificity. RESULTS: A total of 207 patients were included in this study, of which 24 (11.8%) had a clinically important fracture-dislocation. The refined rule consisting of three criteria had a sensitivity of 100% (95% confidence interval [CI] 87.5-100%), specificity of 50% (95% CI 42.5-57.5%), negative predictive value of 100% (95% CI 96-100%), and a negative likelihood ratio of 0.21 (95% CI 0.14-0.30). No patient with an atraumatic, recurrent dislocation had a fracture. Patients over age 35 years had an increased risk of fracture-dislocation if they sustained blunt injury or had a first episode of dislocation. Using this rule could have reduced prereduction radiographs by 44%. CONCLUSION: The refined Fresno-Quebec shoulder dislocation rule detected all clinically important prereduction fracture-dislocations and could have reduced prereduction films by 44%. Prospective validation is warranted.

Validation of the sensitivity of the National Emergency X-Radiography Utilization Study (NEXUS) Head computed tomographic (CT) decision instrument for selective imaging of blunt head injury patients: An observational study.

BACKGROUND: Clinicians, afraid of missing intracranial injuries, liberally obtain computed tomographic (CT) head imaging in blunt trauma patients. Prior work suggests that clinical criteria (National Emergency X-Radiography Utilization Study [NEXUS] Head CT decision instrument [DI]) can reliably identify patients with important injuries, while excluding injury, and the need for imaging in many patients. Validating this DI requires confirmation of the hypothesis that the lower 95% confidence limit for its sensitivity in detecting serious injury exceeds 99.0%. A secondary goal of the study was to complete an independent validation and comparison of the Canadian and NEXUS Head CT rules among the subgroup of patients meeting the inclusion and exclusion criteria. METHODS AND FINDINGS: We conducted a prospective observational study of the NEXUS Head CT DI in 4 hospital emergency departments between April 2006 and December 2015. Implementation of the rule requires that patients satisfy 8 criteria to achieve "low-risk" classification. Patients are excluded from "low-risk" classification and assigned "high-risk" status if they fail to meet 1 or more criteria. We examined the instrument's performance in assigning "high-risk" status to patients requiring neurosurgical intervention among a cohort of 11,770 blunt head injury patients. The NEXUS Head CT DI assigned high-risk status to 420 of 420 patients requiring neurosurgical intervention (sensitivity, 100.0% [95% confidence interval [CI]: 99.1%-100.0%]). The instrument assigned low-risk status to 2,823 of 11,350 patients who did not require neurosurgical intervention (specificity, 24.9% [95% CI: 24.1%-25.7%]). None of the 2,823 low-risk patients required neurosurgical intervention (negative predictive value [NPV], 100.0% [95% CI: 99.9%-100.0%]). The DI assigned high-risk status to 759 of 767 patients with significant intracranial injuries (sensitivity, 99.0% [95% CI: 98.0%-99.6%]). The instrument assigned low-risk status to 2,815 of 11,003 patients who did not have significant injuries (specificity, 25.6% [95% CI: 24.8%-26.4%]). Significant injuries were absent in 2,815 of the 2,823 patients assigned low-risk status (NPV, 99.7% [95% CI: 99.4%-99.9%]). Of our patients, 7,759 (65.9%) met the inclusion and exclusion criteria of the Canadian Head CT rule, including 111 patients (1.43%) who required neurosurgical intervention and 306 (3.94%) who had significant intracranial injuries. In our study, the Canadian criteria for neurosurgical intervention identified 108 of 111 patients requiring neurosurgical intervention to yield a sensitivity of 97.3% (95% CI: 92.3%-99.4%) and exhibited a specificity of 58.8% (95% CI: 57.7%-59.9%). The NEXUS rule, when applied to this same cohort, identified all 111 patients requiring neurosurgical intervention, yielding a sensitivity of 100% (95% CI: 96.7%-100.0%) with a specificity of 32.6% (95% CI: 31.5%-33.6%). Our study found that the Canadian medium-risk factors identified 301 of 306 patients with significant injuries (sensitivity = 98.4%; 95% CI: 96.2%-99.5%), while the NEXUS rule identified 299 of these patients (sensitivity = 97.7%; 95% CI: 95.3%-99.1%). In our study, the Canadian medium-risk rule exhibited a specificity of 12.3% (95% CI: 11.6%-13.1%), while the NEXUS rule exhibited a specificity of 33.3% (95% CI: 32.3%-34.4%). Limitations of the study may arise from application of the rule by different clinicians in different environments. Clinicians may vary in their interpretation and application of the instrument's criteria and risk assignment and may also vary in deciding which patients require intervention. The instrument's specificity is also subject to spectrum bias and may change with variations in the proportion of "low-risk" patients seen in other centers. CONCLUSIONS: The NEXUS Head CT DI reliably identifies blunt trauma patients who require head CT imaging and could significantly reduce the use of CT imaging.

Rib Fracture Diagnosis in the Panscan Era.

STUDY OBJECTIVE: With increased use of chest computed tomography (CT) in trauma evaluation, traditional teachings in regard to rib fracture morbidity and mortality may no longer be accurate. We seek to determine rates of rib fracture observed on chest CT only; admission and mortality of patients with isolated rib fractures, rib fractures observed on CT only, and first or second rib fractures; and first or second rib fracture-associated great vessel injury. METHODS: We conducted a planned secondary analysis of 2 prospectively enrolled cohorts of the National Emergency X-Radiography Utilization Study chest studies, which evaluated patients with blunt trauma who were older than 14 years and received chest imaging in the emergency department. We defined rib fractures and other thoracic injuries according to CT reports and followed patients through their hospital course to determine outcomes. RESULTS: Of 8,661 patients who had both chest radiograph and chest CT, 2,071 (23.9%) had rib fractures, and rib fractures were observed on chest CT only in 1,368 cases (66.1%). Rib fracture patients had higher admission rates (88.7% versus 45.8%; mean difference 42.9%; 95% confidence interval [CI] 41.4% to 44.4%) and mortality (5.6% versus 2.7%; mean difference 2.9%; 95% CI 1.8% to 4.0%) than patients without rib fracture. The mortality of patients with rib fracture observed on chest CT only was not statistically significantly different from that of patients with fractures also observed on chest radiograph (4.8% versus 5.7%; mean difference -0.9%; 95% CI -3.1% to 1.1%). Patients with first or second rib fractures had significantly higher mortality (7.4% versus 4.1%; mean difference 3.3%; 95% CI 0.2% to 7.1%) and prevalence of concomitant great vessel injury (2.8% versus 0.6%; mean difference 2.2%; 95% CI 0.6% to 4.9%) than patients with fractures of ribs 3 to 12, and the odds ratio of great vessel injury with first or second rib fracture was 4.4 (95% CI 1.8 to 10.4). CONCLUSION: Under trauma imaging protocols that commonly incorporate chest CT, two thirds of rib fractures were observed on chest CT only. Patients with rib fractures had higher admission rates and mortality than those without rib fractures. First or second rib fractures were associated with significantly higher mortality and great vessel injury.

Ketamine as a first-line treatment for severely agitated emergency department patients.

OBJECTIVE: Emergency physicians often need to control agitated patients who present a danger to themselves and hospital personnel. Commonly used medications have limitations. Our primary objective was to compare the time to a defined reduction in agitation scores for ketamine versus benzodiazepines and haloperidol, alone or in combination. Our secondary objectives were to compare rates of medication redosing, vital sign changes, and adverse events in the different treatment groups. METHODS: We conducted a single-center, prospective, observational study examining agitation levels in acutely agitated emergency department patients between the ages of 18 and 65 who required sedation medication for acute agitation. Providers measured agitation levels on a previously validated 6-point sedation scale at 0-, 5-, 10-, and 15-min after receiving sedation. We also assessed the incidence of adverse events, repeat or rescue medication dosing, and changes in vital signs. RESULTS: 106 patients were enrolled and 98 met eligibility criteria. There was no significant difference between groups in initial agitation scores. Based on agitation scores, more patients in the ketamine group were no longer agitated than the other medication groups at 5-, 10-, and 15-min after receiving medication. Patients receiving ketamine had similar rates of redosing, changes in vital signs, and adverse events to the other groups. CONCLUSION: In highly agitated and violent emergency department patients, significantly fewer patients receiving ketamine as a first line sedating agent were agitated at 5-, 10-, and 15-min. Ketamine appears to be faster at controlling agitation than standard emergency department medications.

Selective chest imaging for blunt trauma patients: The national emergency X-ray utilization studies (NEXUS-chest algorithm).

Chest imaging plays a prominent role in blunt trauma patient evaluation, but indiscriminate imaging is expensive, may delay care, and unnecessarily exposes patients to potentially harmful ionizing radiation. To improve diagnostic chest imaging utilization, we conducted 3 prospective multicenter studies over 12years to derive and validate decision instruments (DIs) to guide the use of chest x-ray (CXR) and chest computed tomography (CT). The first DI, NEXUS Chest x-ray, consists of seven criteria (Age >60years; rapid deceleration mechanism; chest pain; intoxication; altered mental status; distracting painful injury; and chest wall tenderness) and exhibits a sensitivity of 99.0% (95% confidence interval [CI] 98.2-99.4%) and a specificity of 13.3% (95% CI, 12.6%-14.0%) for detecting clinically significant injuries. We developed two NEXUS Chest CT DIs, which are both highly reliable in detecting clinically major injuries (sensitivity of 99.2%; 95% CI 95.4-100%). Designed primarily to focus on detecting major injuries, the NEXUS Chest CT-Major DI consists of six criteria (abnormal CXR; distracting injury; chest wall tenderness; sternal tenderness; thoracic spine tenderness; and scapular tenderness) and exhibits higher specificity (37.9%; 95% CI 35.8-40.1%). Designed to reliability detect both major and minor injuries (sensitivity 95.4%; 95% CI 93.6-96.9%) with resulting lower specificity (25.5%; 95% CI 23.5-27.5%), the NEXUS CT-All rule consists of seven elements (the six NEXUS CT-Major criteria plus rapid deceleration mechanism). The purpose of this review is to synthesize the three DIs into a novel, cohesive summary algorithm with practical implementation recommendations to guide selective chest imaging in adult blunt trauma patients.

Irrigation of Cutaneous Abscesses Does Not Improve Treatment Success.

STUDY OBJECTIVE: Irrigation of the cutaneous abscess cavity is often described as a standard part of incision and drainage despite no randomized, controlled studies showing benefit. Our goal is to determine whether irrigation of a cutaneous abscess during incision and drainage in the emergency department (ED) decreases the need for further intervention within 30 days compared with no irrigation. METHODS: We performed a single-center, prospective, randomized, nonblinded study of ED patients receiving an incision and drainage for cutaneous abscess, randomized to irrigation or no irrigation. Patient characteristics and postprocedure pain visual analog scale score were obtained. Thirty-day telephone follow-up was conducted with a standardized data form examining need for further intervention, which was defined as repeated incision and drainage, antibiotic change, or abscess-related hospital admission. RESULTS: Of 209 enrolled patients, 187 completed follow-up. The irrigation and no-irrigation groups were similar with respect to diabetes, immunocompromise, fever, abscess size, cellulitis, and abscess location, but the irrigation group was younger (mean age 36 versus 40 years) and more often treated with packing (89% versus 75%) and outpatient antibiotics (91% versus 73%). The need for further intervention was not different in the irrigation (15%) and no-irrigation (13%) groups (difference 2%; 95% confidence interval -8% to 12%). There was no difference in pain visual analog scale scores (5.6 versus 5.7; difference 0.1; 95% confidence interval -0.7 to 0.9). CONCLUSION: Although there were baseline differences between groups, irrigation of the abscess cavity during incision and drainage did not decrease the need for further intervention.

Prevalence of Chest Injury With the Presence of NEXUS Chest Criteria: Data to Inform Shared Decisionmaking About Imaging Use.

STUDY OBJECTIVE: The NEXUS chest decision instrument identifies a very-low-risk population of patients with blunt trauma for whom chest imaging can be avoided. However, it requires that all 7 National Emergency X-Ray Utilization Study (NEXUS) chest criteria be absent. To inform patient and physician shared decisionmaking about imaging, we describe the test characteristics of individual criteria of the NEXUS chest decision instrument and provide the prevalence of injuries when 1, 2, or 3 of the 7 criteria are present. METHODS: We conducted this secondary analysis of 2 prospectively collected cohorts of patients with blunt trauma who were older than 14 years and enrolled in NEXUS chest studies between December 2009 and January 2012. Physicians at 9 US Level I trauma centers recorded the presence or absence of the 7 NEXUS chest criteria. We calculated test characteristics of each criterion and combinations of criteria for the outcome measures of major clinical injuries and thoracic injury observed on chest imaging. RESULTS: We enrolled 21,382 patients, of whom 992 (4.6%) had major clinical injuries and 3,135 (14.7%) had thoracic injuries observed on chest imaging. Sensitivities of individual test characteristics ranged from 15% to 56% for major clinical injury and 14% to 53% for thoracic injury observed on chest imaging, with specificities varying from 71% to 84% for major clinical injury and 67% to 84% for thoracic injury observed on chest imaging. Individual criteria were associated with a prevalence of major clinical injury between 1.9% and 3.8% and of thoracic injury observed on chest imaging between 5.3% and 11.5%. CONCLUSION: Patients with isolated NEXUS chest criteria have low rates of major clinical injury. The risk of major clinical injury for patients with 2 or 3 factors range from 1.7% to 16.6%, depending on the combination of criteria. Criteria-specific risks could be used to inform shared decisionmaking about the need for imaging by patients and their physicians.

Derivation and validation of two decision instruments for selective chest CT in blunt trauma: a multicenter prospective observational study (NEXUS Chest CT).

BACKGROUND: Unnecessary diagnostic imaging leads to higher costs, longer emergency department stays, and increased patient exposure to ionizing radiation. We sought to prospectively derive and validate two decision instruments (DIs) for selective chest computed tomography (CT) in adult blunt trauma patients. METHODS AND FINDINGS: From September 2011 to May 2014, we prospectively enrolled blunt trauma patients over 14 y of age presenting to eight US, urban level 1 trauma centers in this observational study. During the derivation phase, physicians recorded the presence or absence of 14 clinical criteria before viewing chest imaging results. We determined injury outcomes by CT radiology readings and categorized injuries as major or minor according to an expert-panel-derived clinical classification scheme. We then employed recursive partitioning to derive two DIs: Chest CT-All maximized sensitivity for all injuries, and Chest CT-Major maximized sensitivity for only major thoracic injuries (while increasing specificity). In the validation phase, we employed similar methodology to prospectively test the performance of both DIs. We enrolled 11,477 patients-6,002 patients in the derivation phase and 5,475 patients in the validation phase. The derived Chest CT-All DI consisted of (1) abnormal chest X-ray, (2) rapid deceleration mechanism, (3) distracting injury, (4) chest wall tenderness, (5) sternal tenderness, (6) thoracic spine tenderness, and (7) scapular tenderness. The Chest CT-Major DI had the same criteria without rapid deceleration mechanism. In the validation phase, Chest CT-All had a sensitivity of 99.2% (95% CI 95.4%-100%), a specificity of 20.8% (95% CI 19.2%-22.4%), and a negative predictive value (NPV) of 99.8% (95% CI 98.9%-100%) for major injury, and a sensitivity of 95.4% (95% CI 93.6%-96.9%), a specificity of 25.5% (95% CI 23.5%-27.5%), and a NPV of 93.9% (95% CI 91.5%-95.8%) for either major or minor injury. Chest CT-Major had a sensitivity of 99.2% (95% CI 95.4%-100%), a specificity of 31.7% (95% CI 29.9%-33.5%), and a NPV of 99.9% (95% CI 99.3%-100%) for major injury and a sensitivity of 90.7% (95% CI 88.3%-92.8%), a specificity of 37.9% (95% CI 35.8%-40.1%), and a NPV of 91.8% (95% CI 89.7%-93.6%) for either major or minor injury. Regarding the limitations of our work, some clinicians may disagree with our injury classification and sensitivity thresholds for injury detection. CONCLUSIONS: We prospectively derived and validated two DIs (Chest CT-All and Chest CT-Major) that identify blunt trauma patients with clinically significant thoracic injuries with high sensitivity, allowing for a safe reduction of approximately 25%-37% of unnecessary chest CTs. Trauma evaluation protocols that incorporate these DIs may decrease unnecessary costs and radiation exposure in the disproportionately young trauma population.

Prevalence and Clinical Import of Thoracic Injury Identified by Chest Computed Tomography but Not Chest Radiography in Blunt Trauma: Multicenter Prospective Cohort Study.

STUDY OBJECTIVE: Chest computed tomography (CT) diagnoses more injuries than chest radiography, so-called occult injuries. Wide availability of chest CT has driven substantial increase in emergency department use, although the incidence and clinical significance of chest CT findings have not been fully described. We determine the frequency, severity, and clinical import of occult injury, as determined by changes in management. These data will better inform clinical decisions, need for chest CT, and odds of intervention. METHODS: Our sample included prospective data (2009 to 2013) on 5,912 patients at 10 Level I trauma center EDs with both chest radiography and chest CT at physician discretion. These patients were 40.6% of 14,553 enrolled in the parent study who had either chest radiography or chest CT. Occult injuries were pneumothorax, hemothorax, sternal or greater than 2 rib fractures, pulmonary contusion, thoracic spine or scapula fracture, and diaphragm or great vessel injury found on chest CT but not on preceding chest radiography. A priori, we categorized thoracic injuries as major (having invasive procedures), minor (observation or inpatient pain control >24 hours), or of no clinical significance. Primary outcome was prevalence and proportion of occult injury with major interventions of chest tube, mechanical ventilation, or surgery. Secondary outcome was minor interventions of admission rate or observation hours because of occult injury. RESULTS: Two thousand forty-eight patients (34.6%) had chest injury on chest radiography or chest CT, whereas 1,454 of these patients (71.0%, 24.6% of all patients) had occult injury. Of these, in 954 patients (46.6% of injured, 16.1% of total), chest CT found injuries not observed on immediately preceding chest radiography. In 500 more patients (24.4% of injured patients, 8.5% of all patients), chest radiography found some injury, but chest CT found occult injury. Chest radiography found all injuries in only 29.0% of injured patients. Two hundred and two patients with occult injury (of 1,454, 13.9%) had major interventions, 343 of 1,454 (23.6%) had minor interventions, and 909 (62.5%) had no intervention. Patients with occult injury included 514 with pulmonary contusions (of 682 total, 75.4% occult), 405 with pneumothorax (of 597 total, 67.8% occult), 184 with hemothorax (of 230 total, 80.0% occult), those with greater than 2 rib fractures (n=672/1,120, 60.0% occult) or sternal fracture (n=269/281, 95.7% occult), 12 with great vessel injury (of 18 total, 66.7% occult), 5 with diaphragm injury (of 6, 83.3% occult), and 537 with multiple occult injuries. Interventions for patients with occult injury included mechanical ventilation for 31 of 514 patients with pulmonary contusion (6.0%), chest tube for 118 of 405 patients with pneumothorax (29.1%), and 75 of 184 patients with hemothorax (40.8%). Inpatient pain control or observation greater than 24 hours was conducted for 183 of 672 patients with rib fractures (27.2%) and 79 of 269 with sternal fractures (29.4%). Three of 12 (25%) patients with occult great vessel injuries had surgery. Repeated imaging was conducted for 50.6% of patients with occult injury (88.1% chest radiography, 11.9% chest CT, 7.5% both). For patients with occult injury, 90.9% (1,321/1,454) were admitted, with 9.1% observed in the ED for median 6.9 hours. Forty-four percent of observed patients were then admitted (4.0% of patients with occult injury). CONCLUSION: In a more seriously injured subset of patients with blunt trauma who had both chest radiography and chest CT, occult injuries were found by chest CT in 71% of those with thoracic injuries and one fourth of all those with blunt chest trauma. More than one third of occult injury had intervention (37.5%). Chest tubes composed 76.2% of occult injury major interventions, with observation or inpatient pain control greater than 24 hours in 32.4% of occult fractures. Only 1 in 20 patients with occult injury was discharged home from the ED. For these patients with blunt trauma, chest CT is useful to identify otherwise occult injuries.

Urinalysis is an inadequate screen for rhabdomyolysis.

STUDY OBJECTIVES: Hematuria by urine dipstick with absent red blood cells (RBCs) on microscopy is indicative of rhabdomyolysis. We determined the sensitivity of this classic urinalysis (UA) finding in the diagnosis of rhabdomyolysis. METHODS: We conducted a retrospective electronic medical record review of patients with a primary or secondary diagnosis of rhabdomyolysis with a creatine phosphokinase (CPK) greater than 1000 IU/L and a UA within the first 24 hours. Data were collected using a standardized data form, and a blinded panel of 3 emergency medicine physicians reviewed selected cases. Sensitivity and 95% confidence intervals (CIs) were calculated for detection of rhabdomyolysis by UA. RESULTS: During the study period, 1796 patients were diagnosed with rhabdomyolysis, of whom 228 met inclusion criteria. The mean peak CPK was 27509 IU/L. One hundred ninety-five (86%) had a urine dip-positive for blood. However, only 94 patients (41%) had a positive urine dip and negative microscopic hematuria, resulting in a sensitivity of 41% (95% CI, 35%-47%). In a subset of 66 patients (29%) with more severe rhabdomyolysis (initial CPK, ≥10000 IU/L; mean CPK, 53365 IU/L), UA had a sensitivity of 55% (95% CI, 43%-67%). Broadening the definition of negative microscopy from 0 to 3 RBCs to less than 10 RBCs only increased the sensitivity to 79% (95% CI, 73%-83%). CONCLUSIONS: The combination of a positive urine dip for blood and negative microscopy is an insensitive test for rhabdomyolysis, and the absence of this finding should not be used to exclude the diagnosis.

Traumatic injury to the posterior fossa: a secondary analysis and description of case series from the NEXUS head injury dataset.

Background: Traumatic brain injuries involving the posterior fossa are rare and case reports indicate they often result in severe outcomes. We seek to describe characteristics and outcomes of traumatic posterior fossa injuries. Methods: We performed a planned secondary analysis of all patients with posterior fossa injuries enrolled in the NEXUS head computed tomography (CT) validation study dataset. The dataset includes prospectively collected data on all patients undergoing non-contrast cranial CT following blunt traumatic head injury from April 2006 to December 2015, at four emergency departments comprising community and university sites, as well as urban, suburban and rural settings in California (Antelope Valley Hospital, San Francisco General Hospital, UCLA Ronald Reagan Medical Center, UCSF Fresno Community Regional Medical Center). We classified each patient into one of three injury patterns: Type I-notable traumatic injuries primarily above the tentorium, with minimal posterior fossa involvement; Type II-notable traumatic injuries both above and within the posterior fossa; and Type III-notable traumatic injuries primarily within the posterior fossa. We extracted demographic data for each patient as well as physician assessments of the NEXUS head CT and Canadian Head CT rule clinical criteria, mechanisms of injury, patient outcomes, and the location and types of intracranial injuries sustained. Findings: Of 11,770 patients in the database, 184 (1.6%) had posterior fossa injuries on CT imaging. Mean age was 55.4 years (standard deviation 22.5 years, range 2-96 years); 131 (71.2%) were males. We identified 63 patients with Type I injuries, 87 with Type II injuries, and 34 Type III injuries. The most common mechanisms of injury were falls (41%), pedestrian vs automobile (15%), and motor vehicle collisions (13%). On presentation most patients had altered mental status (72%), abnormal behavior (53%), or a neurologic deficit (55%). The majority of individuals, 151 (82%), had clinically important injuries and 111 (60%) required neurosurgical intervention. The dispositions for the subjects included 52 deaths (28%), 49 (27%) patients discharged home, and 48 (26%) discharged to rehabilitation facilities. When compared to individuals with Type I and Type II injuries, patients with Type III injuries had lower mortality (6% vs 30% and 35%) and higher percentage of patients discharged home (60% vs 19% and 21%). Interpretation: Patients with Type I and II injury patterns (those that involve both the posterior fossa and supratentorium) experienced high mortality and disability. Patients with Type III injuries (isolated posterior fossa) had a better prognosis. Funding: None.

A randomized, double-blind, placebo-controlled trial of a highly purified equine F(ab)2 antibody black widow spider antivenom.

STUDY OBJECTIVE: Black widow spider antivenom has never been tested in a randomized clinical trial, to our knowledge. We explore various efficacy measures for a novel F(ab)2 antivenom in patients with moderate to severe pain caused by black widow spider envenomation. METHODS: A randomized, placebo-controlled, double-blind, clinical trial was conducted in 12 academic emergency departments. We included patients at least 10 years old with moderate to severe latrodectism. Subjects received either a single intravenous infusion of antivenom or placebo. Pain was assessed with the visual analog scale. The primary efficacy outcome was the difference in pre- and posttreatment visual analog scale score. Prospectively defined secondary outcomes included treatment failures and time to clinically important decrease in pain. RESULTS: Twenty-four subjects were enrolled between October 2005 and October 2006; 13 were randomized to antivenom and 11 to placebo. The median change in visual analog scale at 150 minutes posttreatment was -50.0 mm (Interquartile Range [IQR] -67, -41 mm) in the antivenom treatment group and -46.0 mm (IQR -51, 0 mm) in the placebo treatment group (P=.14). There were 7 treatment failures (64%; 95% confidence interval 35% to 92%) in the placebo group and 3 (23%; 95% confidence interval 0.2% to 46%) in the antivenom group (P=.06). The median time to a clinically important decrease in pain after treatment was shorter in the antivenom group compared with the placebo group (30 minutes [IQR 30, 60 minutes] versus 90 minutes [IQR 30, 90 minutes]; P=.03). No serious adverse events or deaths were reported. CONCLUSION: Although the overall reduction in pain was similar for antivenom- and placebo-treated subjects, antivenom reduced pain more rapidly than placebo. No significant adverse events occurred in either group.