Julian Villar

Prevalence and clinical import of thoracic injury identified by chest computed tomography but not chest radiography in blunt trauma: Multicenter prospective cohort study presented at the western regional society for academic emergency medicine meeting, March 2014, Irvine, CA; And the Society for Academic Emergency Medicine national meeting, May 2014, Dallas, TX.

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.

Many emergency department patients with severe sepsis and septic shock do not meet diagnostic criteria within 3 hours of arrival.

STUDY OBJECTIVE Proposed national performance measures for severe sepsis or septic shock include interventions within 3 hours of emergency department (ED) arrival rather than from time of first meeting diagnostic criteria. We aim to determine the percentage of ED patients who first meet criteria greater than 3 hours after arrival. METHODS We conducted a retrospective analysis of adult patients with severe sepsis or septic shock in 2 EDs (university hospital [September 2012 to June 2013] and public trauma center [December 2012 to May 2013]). Times of ED arrival and first meeting clinical criteria were collected for quality assurance programs, which differed between institutions. At the university hospital, patients with admission diagnoses consistent with infection were included. Clinical presentation was defined as time meeting 2 or more systemic inflammatory response syndrome criteria and evidence of end-organ dysfunction. At the trauma center, only patients with hospital discharge diagnoses consistent with infection were included. Clinical presentation was defined by time of end-organ dysfunction. RESULTS Three hundred seventy-two patients met inclusion criteria at the university hospital and 133 at the trauma center. Median times from ED arrival to first meeting criteria were 68 minutes (interquartile range 34 to 130 minutes) and 31 minutes (interquartile range 8 to 73 minutes), respectively; 15.3% (95% confidence interval 11.9% to 19.3%) and 9.8% (95% confidence interval 5.5% to 15.7%) first met criteria greater than 3 hours from ED arrival, respectively. CONCLUSION Compliance with a performance metric for severe sepsis and septic shock within 3 hours of ED arrival would require application of this measure to patients who do not meet diagnostic criteria, potentially resulting in unnecessary interventions. Measure developers should consider these findings.

The Absence of Gallstones on Point-of-Care Ultrasound Rules Out Acute Cholecystitis.

BACKGROUND Cholelithiasis affects an estimated 20 million people in the United States yearly; 20% of symptomatic patients will develop acute cholecystitis (AC). A recent single-center study estimating test characteristics of point-of-care ultrasonography (POCUS) for the detection of AC, as defined by gallstones plus sonographic Murphys or pericholecystic fluid or gallbladder wall-thickening, resulted in a sensitivity and specificity of 87% (95% confidence interval [CI] 66-97) and 82% (95% CI 74-88), respectively. No prior studies have been conducted to estimate the test characteristics of POCUS for the purpose of excluding acute calculous cholecystitis. OBJECTIVE To determine whether the finding of gallstones alone on POCUS has high sensitivity, high negative predictive value, and low negative likelihood ratio for the exclusion of AC. METHODS We conducted an analysis using data from a prospective cross-sectional single-center study of POCUS test to estimate the test characteristics using a simplified definition of a positive test - the presence of gallstones alone. Clinical follow-up and pathology reports were used as the reference standard. Test characteristics were calculated and compared to the standard definition, gallstones plus one secondary finding. RESULTS The overall prevalence of AC was 14% (23 pathology-confirmed cases of 164 included patients). The sensitivity of the simplified definition was 100% (95% CI 85.7-100), negative predictive value 100% (95% CI 92.2-100), and negative likelihood ratio was < 0.1, compared to a sensitivity of 87% (95% CI 66-97%), negative predictive value 97% (95% CI 93-99%), and negative likelihood ratio of 0.16 (95% CI 0.06-0.5). CONCLUSION Simplifying the definition of the test findings on POCUS to gallstones alone has excellent sensitivity and negative predictive value for the exclusion of AC. This finding, if broadly validated prospectively, confirms the practice of excluding acute calculous cholecystitis using POCUS in emergency department patients.

Factors and outcomes associated with inpatient cardiac arrest following emergent endotracheal intubation

BACKGROUND Inpatient peri-intubation cardiac arrest (PICA) following emergent endotracheal intubation (ETI) is an uncommon but potentially preventable type of cardiac arrest (CA). Limited published data exist describing factors associated with inpatient PICA and patient outcomes. This study identifies risk factors associated with PICA among hospitalized patients emergently intubated out of the operating room and compares PICA to other types of inpatient CA. METHODS Retrospective case-control study of patients at our institution over a five-year period. Cases were defined as inpatients emergently intubated outside of the operating room that experienced cardiac arrest within 20min after ETI. The control group consisted of inpatients emergently intubated out of the operating room without CA. Predictors of PICA were identified through univariate and multivariate analysis. Clinical outcomes were compared between PICA and other inpatient CAs, identified through a prospectively enrolled CA registry at our institution. RESULTS 29 episodes of PICA occurred over 5 years, accounting for 5% of all inpatient arrests. Shock index ≥1.0, intubation within one hour of nursing shift change, and use of succinylcholine were independently associated with PICA. Sustained ROSC, survival to discharge, and neurocognitive outcome did not differ significantly between groups. CONCLUSION Patients outcomes following PICA were comparable to other causes of inpatient CA. Potentially modifiable factors were associated with PICA. Hemodynamic resuscitation, optimized staffing strategies, and possible avoidance of succinylcholine were associated with decreased risk of PICA. Clinical trials testing targeted strategies to optimize peri-intubation care are needed to identify effective interventions to prevent this potentially avoidable type of CA.

Evaluating vancomycin and piperacillin-tazobactam in emergency department patients with severe sepsis and septic shock

Study objective: To determine the frequency and cause of inadequate initial antibiotic therapy with vancomycin and piperacillin‐tazobactam in patients with severe sepsis and septic shock in the emergency department (ED), characterize its impact on patient outcomes, and identify patients who would benefit from an alternative initial empiric regimen. Methods: Retrospective cohort study conducted between 2012 and 2015 in which 342 patients with culture‐positive severe sepsis or septic shock who received initial vancomycin and piperacillin‐tazobactam were reviewed to determine appropriateness of antimicrobial therapy, risk factors for inappropriate use, and outcome data. Univariate and multivariate regression analyses were determined to identify associations between inappropriate antibiotic use and outcomes and to identify risk factors that may predict which patients would benefit from an alternative initial regimen. Results: Vancomycin and piperacillin‐tazobactam were inappropriate for 24% of patients with severe sepsis or septic shock, largely due to non‐susceptible infections, particularly ESBL organisms and Clostridium difficile. Risk factors included multiple sources of infection (OR 4.383), admission from a skilled nursing facility (OR 3.763), a history of chronic obstructive pulmonary disease (COPD) (OR 3.175), intra‐abdominal infection (OR 2.890), and immunosuppression (OR 1.930). We did not find a mortality impact. Conclusion: Vancomycin and piperacillin‐tazobactam were an inappropriate antibiotic combination for approximately 24% of patients with either severe sepsis or septic shock in the ED. Patients with known COPD, residence at a skilled nursing facility, a history concerning for Clostridium difficile, and immunosuppression would benefit from an alternative regimen. Future prospective studies are needed to validate these findings.