Independent evaluation of a simple clinical prediction rule to identify right ventricular dysfunction in patients with shortness of breath.

BACKGROUND: Many patients have unexplained persistent dyspnea after negative computed tomographic pulmonary angiography (CTPA). We hypothesized that many of these patients have isolated right ventricular (RV) dysfunction from treatable causes. We previously derived a clinical decision rule (CDR) for predicting RV dysfunction consisting of persistent dyspnea and normal CTPA, finding that 53% of CDR-positive patients had isolated RV dysfunction. Our goal is to validate this previously derived CDR by measuring the prevalence of RV dysfunction and outcomes in dyspneic emergency department patients. METHODS: A secondary analysis of a prospective observational multicenter study that enrolled patients presenting with suspected PE was performed. We included patients with persistent dyspnea, a nonsignificant CTPA, and formal echo performed. Right ventricular dysfunction was defined as RV hypokinesis and/or dilation with or without moderate to severe tricuspid regurgitation. RESULTS: A total of 7940 patients were enrolled. Two thousand six hundred sixteen patients were analyzed after excluding patients without persistent dyspnea and those with a significant finding on CTPA. One hundred ninety eight patients had echocardiography performed as standard care. Of those, 19% (95% confidence interval [CI], 14%-25%) and 33% (95% CI, 25%-42%) exhibited RV dysfunction and isolated RV dysfunction, respectively. Patients with isolated RV dysfunction or overload were more likely than those without RV dysfunction to have a return visit to the emergency department within 45 days for the same complaint (39% vs 18%; 95% CI of the difference, 4%-38%). CONCLUSION: This simple clinical prediction rule predicted a 33% prevalence of isolated RV dysfunction or overload. Patients with isolated RV dysfunction had higher recidivism rates and a trend toward worse outcomes.

Can USMLE and COMLEX-USA Scores Predict At-Risk Emergency Medicine Residents' Performance on In-Training Examinations?

PURPOSE: The United States Medical Licensing Examination (USMLE) and Comprehensive Osteopathic Medical Licensing Examination (COMLEX) scores are standard methods used to determine residency candidates' medical knowledge. The authors were interested in using the USMLE and COMLEX part 2 scores in our emergency medicine (EM) residency program to identify at-risk residents who may have difficulty on the in-training exam (ITE) and to determine the cutoff values under which an intern could be given an individualized study plan to ensure medical knowledge competency. METHODS: The authors abstracted the USMLE and COMLEX part 2 scores and the American Board of Emergency Medicine (ABEM) ITE scores for a cohort of first-year EM residents graduating years 2010-2022, converting raw scores to percentiles, and compared part 2 and ABEM ITE scores with Pearson's correlation, a Bland-Altman analysis of bias and 95% limits of agreement, and ROC analysis to determine optimal the cut-off values for predicting ABEM ITE < 50th percentile and the estimated test characteristics. RESULTS: Scores were available for 152 residents, including 93 USMLE and 88 COMLEX exams. The correlations between part 2 scores and ABEM ITE were r = 0.36 (95%CI: 0.17, 0.52; p < 0.001) for USMLE and r = 0.50 (95%CI: 0.33, 0.64; p < 0.001) for COMLEX. Bias and limits of agreement for both part 2 scores were -14 ± 63% for USMLE and 13 ± 50% for COMLEX in predicting the ABEM ITE scores. USMLE < 37th percentile and COMLEX < 53rd percentile identified 42% (N = 39) and 27% (N = 24) of EM residents, respectively, as at risk, with a sensitivity of 61% and 49% and specificity of 71% and 92%, respectively. CONCLUSION: USMLE and COMLEX part 2 scores have a very limited role in identifying those at risk of low ITE performance, suggesting that other factors should be considered to identify interns in need of medical knowledge remediation.

Orbital compartment syndrome: Pearls and pitfalls for the emergency physician.

Orbital compartment syndrome (OCS) is a rare, vision-threatening diagnosis that requires rapid identification and immediate treatment for preservation of vision. Because of the time-sensitive nature of this condition, the emergency physician plays a critical role in the diagnosis and management of OCS, which is often caused by traumatic retrobulbar hemorrhage. In this review, we outline pearls and pitfalls for the identification and treatment of OCS, highlighting lateral canthotomy and inferior cantholysis (LCIC), a crucial skill for the emergency physician. We recommend adequate preparation for the diagnosis and procedure, early consultation to ophthalmology, clear and thorough documentation of the physical examination, avoidance of iatrogenic injury during LCIC, and complete division of the inferior canthal tendon. Emergency physicians should avoid failing to make the diagnosis of OCS, delaying definitive surgical treatment, overrelying on imaging, failing to decrease intraocular pressure, and failing to exclude globe rupture. The emergency physician should be appropriately trained to identify signs and symptoms of OCS and perform LCIC in a timely manner.

Clinical features from the history and physical examination that predict the presence or absence of pulmonary embolism in symptomatic emergency department patients: results of a prospective, multicenter study.

STUDY OBJECTIVE: Prediction rules for pulmonary embolism use variables explicitly shown to estimate the probability of pulmonary embolism. However, clinicians often use variables that have not been similarly validated, yet are implicitly believed to modify probability of pulmonary embolism. The objective of this study is to measure the predictive value of 13 implicit variables. METHODS: Patients were enrolled in a prospective cohort study from 12 centers in the United States; all had an objective test for pulmonary embolism (D-dimer, computed tomographic angiography, or ventilation-perfusion scan). Clinical features including 12 predefined previously validated (explicit) variables and 13 variables not part of existing prediction rules (implicit) were prospectively recorded at presentation. The primary outcome was venous thromboembolism (pulmonary embolism or deep venous thrombosis), diagnosed by imaging up to 45 days after enrollment. Variables with adjusted odds ratios from logistic regression with 95% confidence intervals not crossing unity were considered significant. RESULTS: Seven thousand nine hundred forty patients (7.2% venous thromboembolism positive) were enrolled. Mean age was 49 years (standard deviation 17 years) and 67% were female patients. Eight of 13 implicit variables were significantly associated with venous thromboembolism; those with an adjusted odds ratio (OR) greater than 1.5 included non-cancer-related thrombophilia (OR 1.99), pleuritic chest pain (OR 1.53), and family history of venous thromboembolism (OR 1.51). Implicit variables that predicted no venous thromboembolism outcome included substernal chest pain, female sex, and smoking. Nine of 12 explicit variables predicted a positive outcome of venous thromboembolism, including patient history of pulmonary embolism or deep venous thrombosis in the past, unilateral leg swelling, recent surgery, estrogen, hypoxemia, and active malignancy. CONCLUSION: In symptomatic outpatients being considered for possible pulmonary embolism, non-cancer-related thrombophilia, pleuritic chest pain, and family history of venous thromboembolism increase probability of pulmonary embolism or deep venous thrombosis. Other variables that are part of existing pretest probability systems were validated as important predictors in this diverse sample of US emergency department patients.

12-lead ECG findings of pulmonary hypertension occur more frequently in emergency department patients with pulmonary embolism than in patients without pulmonary embolism.

STUDY OBJECTIVE: Acute pulmonary embolism can produce abnormalities on ECG that reflect severity of pulmonary hypertension. Early recognition of these findings may alter the estimated pretest probability of pulmonary embolism and prompt more aggressive treatment before hemodynamic instability ensues, but it is first important to test whether these findings are specific to patients with pulmonary embolism. We hypothesize that ECG findings consistent with pulmonary hypertension would be observed more frequently in patients with pulmonary embolism. METHODS: Secondary analysis of a prospective, observational cohort of emergency department patients who were tested for pulmonary embolism. ECGs were ordered at clinician's discretion and interpreted at presentation. RESULTS: Six thousand forty-nine patients had an ECG, 354 (5.9%) of whom were diagnosed with pulmonary embolism. The frequency, positive likelihood ratio (LR+) and 95% confidence interval (CI) of each predictor were as follows: S1Q3T3 8.5% with pulmonary embolism versus 3.3% without pulmonary embolism (LR+ 3.7; 95% CI 2.5 to 5.4); nonsinus rhythm, 23.5% versus 16.6% (LR+ 1.4; 95% CI 1.2 to 1.7); inverted T waves in V1 to V2, 14.4% versus 8.1% (LR+ 1.8; 95% CI 1.3 to 2.3); inversion in V1 to V3, 10.5% versus 4.0% (LR+ 2.6; 95% CI 1.9 to 3.6); inversion in V1 to V4, 7.3% versus 2.0% (LR+ 3.7; 95% CI 2.4 to 5.5); incomplete right bundle branch block, 4.8% versus 2.8% (LR+ 1.7; 95% CI 1.0 to 2.7); tachycardia (pulse rate >100 beats/min), 28.8% versus 15.7% (LR+ 1.8; 95% CI 1.5 to 2.2). Likelihood ratios and specificities were similar when patients with previous cardiopulmonary disease were excluded from analysis. CONCLUSION: Findings of acute pulmonary hypertension were infrequent overall but were observed more frequently in patients with the final diagnosis of pulmonary embolism compared with patients who do not have pulmonary embolism.

Effect of pulmonary-generated reactive oxygen species on left-ventricular dysfunction associated with cardio-pulmonary ischemia-reperfusion injury.

The purpose of the present study was to demonstrate the contribution of pulmonary-generated reactive oxygen species (ROS) on cardiac dysfunction using a rat model of ischemia-reperfusion (IR) injury. Three groups of rats were subjected to regional IR injury in (i) lung, (ii) heart, (iii) lung + heart. A fourth (control) group of rats were instrumented using the same methods but without induction IR. Hemodynamic data were recorded in real time. Blood from the proximal aorta was sampled during baseline, ischemia, and reperfusion, mixed with α-phenyl-N-tert-butylnitrone (PBN) for measuring ROS by electron paramagnetic resonance spectrometry. Data were analyzed by a two-way analysis of variance. The results showed that the lung IR generated an increased burst of ROS that resulted in significant cardiac dysfunction, including hypotension and ECG changes. The results indicated that generation of ROS as a result of acute IR lung injury may be sufficiently large enough to cause direct cardiac dysfunction that is independent of injury caused to the myocardium as a result of regional myocardial IR injury alone.

Evaluation of pulmonary embolism in the emergency department and consistency with a national quality measure: quantifying the opportunity for improvement.

BACKGROUND: The National Quality Forum (NQF) has endorsed a performance measure designed to increase imaging efficiency for the evaluation of pulmonary embolism (PE) in the emergency department (ED). To our knowledge, no published data have examined the effect of patient-level predictors on performance. METHODS: To quantify the prevalence of avoidable imaging in ED patients with suspected PE, we performed a prospective, multicenter observational study of ED patients evaluated for PE from 2004 through 2007 at 11 US EDs. Adult patients tested for PE were enrolled, with data collected in a standardized instrument. The primary outcome was the proportion of imaging that was potentially avoidable according to the NQF measure. Avoidable imaging was defined as imaging in a patient with low pretest probability for PE, who either did not have a D-dimer test ordered or who had a negative D-dimer test result. We performed subanalyses testing alternative pretest probability cutoffs and imaging definitions on measure performance as well as a secondary analysis to identify factors associated with inappropriate imaging. χ(2) Test was used for bivariate analysis of categorical variables and multivariable logistic regression for the secondary analysis. RESULTS: We enrolled 5940 patients, of whom 4113 (69%) had low pretest probability of PE. Imaging was performed in 2238 low-risk patients (38%), of whom 811 had no D-dimer testing, and 394 had negative D-dimer test results. Imaging was avoidable, according to the NQF measure, in 1205 patients (32%; 95% CI, 31%-34%). Avoidable imaging owing to not ordering a D-dimer test was associated with age (odds ratio [OR], 1.15 per decade; 95% CI, 1.10-1.21). Avoidable imaging owing to imaging after a negative D-dimer test result was associated with inactive malignant disease (OR, 1.66; 95% CI, 1.11-2.49). CONCLUSIONS: One-third of imaging performed for suspected PE may be categorized as avoidable. Improving adherence to established diagnostic protocols is likely to result in significantly fewer patients receiving unnecessary irradiation and substantial savings.

Factors associated with positive D-dimer results in patients evaluated for pulmonary embolism.

OBJECTIVES: Available D-dimer assays have low specificity and may increase radiographic testing for pulmonary embolism (PE). To help clinicians better target testing, this study sought to quantify the effect of risk factors for a positive quantitative D-dimer in patients evaluated for PE. METHODS: This was a prospective, multicenter, observational study. Emergency department (ED) patients evaluated for PE with a quantitative D-dimer were eligible for inclusion. The main outcome of interest was a positive D-dimer. Odds ratio (ORs) and 95% confidence intervals (CIs) were determined by multivariable logistic regression. Adjusted estimates of relative risk were also calculated. RESULTS: A total of 4,346 patients had D-dimer testing, of whom 2,930 (67%) were women. A total of 2,500 (57%) were white, 1,474 (34%) were black or African American, 238 (6%) were Hispanic, and 144 (3%) were of other race or ethnicity. The mean (+/-SD) age was 48 (+/-17) years. Overall, 1,903 (44%) D-dimers were positive. Model fit was adequate (c-statistic = 0.739, Hosmer and Lemeshow p-value = 0.13). Significant positive predictors of D-dimer positive included female sex; increasing age; black (vs. white) race; cocaine use; general, limb, or neurologic immobility; hemoptysis; hemodialysis; active malignancy; rheumatoid arthritis; lupus; sickle cell disease; prior venous thromboembolism (VTE; not under treatment); pregnancy and postpartum state; and abdominal, chest, orthopedic, or other surgery. Warfarin use was protective. In contrast, several variables known to be associated with PE were not associated with positive D-dimer results: body mass index (BMI), estrogen use, family history of PE, (inactive) malignancy, thrombophilia, trauma within 4 weeks, travel, and prior VTE (under treatment). CONCLUSIONS: Many factors are associated with a positive D-dimer test. The effect of these factors on the usefulness of the test should be considered prior to ordering a D-dimer.

Potential impact of adjusting the threshold of the quantitative D-dimer based on pretest probability of acute pulmonary embolism.

OBJECTIVES: The utility of D-dimer testing for suspected pulmonary embolism (PE) can be limited by test specificity. The authors tested if the threshold of the quantitative D-dimer can be varied according to pretest probability (PTP) of PE to increase specificity while maintaining a negative predictive value (NPV) of >99%. METHODS: This was a prospective, observational multicenter study of emergency department (ED) patients in the United States. Eligible patients had a diagnostic study ordered to evaluate possible PE. PTP was determined by the clinician's unstructured estimate and the Wells score. Five different D-dimer assays were used. D-dimer test performance was measured using 1) standard thresholds and 2) variable threshold values: twice (for low PTP patients), equal (intermediate PTP patients), or half (high PTP patients) of standard threshold. Venous thromboembolism (VTE) within 45 days required positive imaging plus decision to treat. RESULTS: The authors enrolled 7,940 patients tested for PE, and clinicians ordered a quantitative D-dimer for 4,357 (55%) patients who had PTPs distributed as follows: low (74%), moderate (21%), or high (4%). At standard cutoffs, across all PTP strata, quantitative D-dimer testing had a test sensitivity of 94% (95% confidence interval [CI] = 91% to 97%), specificity of 58% (95% CI = 56% to 60%), and NPV of 99.5% (95% CI = 99.1% to 99.7%). If variable cutoffs had been used the overall sensitivity would have been 88% (95% CI = 83% to 92%), specificity 75% (95% CI = 74% to 76%), and NPV 99.1% (95% CI = 98.7% to 99.4%). CONCLUSIONS: This large multicenter observational sample demonstrates that emergency medicine clinicians currently order a D-dimer in the majority of patients tested for PE, including a large proportion with intermediate PTP and high PTP. Varying the D-dimer's cutoff according to PTP can increase specificity with no measurable decrease in NPV.

Self-reported pain scores in the emergency department: lack of association with vital signs.

BACKGROUND: Some practitioners and investigators have presumed relationships between pain scores and heart rate, blood pressure, or respiratory rate. Previous literature has not adequately addressed the association of pain and vital signs. OBJECTIVES: To identify any association between self-reported pain and heart rate, blood pressure, or respiratory rate. METHODS: In this retrospective, observational study, emergency department patients older than 17 years of age presenting between May 2004 and April 2005 with verifiable painful diagnoses (including nephrolithiasis, myocardial infarction, small bowel obstruction, fracture, burn, crush injury, stab wound, amputation, corneal abrasion, and dislocation) were identified. Data were extracted from the hospital's database, including patients' age, gender, emergency department diagnosis, self-reported pain score, heart rate, blood pressure, and respiratory rate. RESULTS: Among 1,063 subjects, the most common diagnoses were nephrolithiasis (25%; n = 267) and fracture (23%; n = 249). The mean (+/- SD) triage pain score was 7 (+/- 3). The mean (+/- SD) heart rate was 85 (+/- 16) beats/min, mean (+/- SD) systolic blood pressure was 141 (+/- 23) mm Hg, and mean (+/- SD) respiratory rate was 19 (+/- 3) breaths/min. There were no clinically significant differences in mean vital signs across the individual pain scores, as demonstrated by overlapping confidence intervals across pain scores. CONCLUSIONS: No clinically significant associations were identified between self-reported triage pain scores and heart rate, blood pressure, or respiratory rate.

The verbal numeric pain scale: effects of patient education on self-reports of pain.

BACKGROUND: Emergency department (ED) patients are frequently asked to provide a self-report of the level of pain experienced using a verbal numeric rating scale. OBJECTIVES: To determine the effects of patient education regarding the verbal numeric rating scale on self-reports of pain among ED patients. METHODS: In this prospective, interventional study, 310 eligible ED patients with pain, aged 18 years and older, were randomized to view either a novel educational video (n = 155) or a novel print brochure (n = 155) as an educational intervention, both developed to deliver educational information about the verbal numeric pain scale and its use. Participants initially rated their pain on a scale from 0 to 10 and then were administered the educational intervention. Following the educational intervention, participants completed a survey that included demographic information, postinterventional pain score, prior pain experience, and subjective rating of the helpfulness of the educational intervention. Fifty-five consecutive participants were enrolled as controls and received no educational intervention but gave a self-reported triage pain score and a second pain score at an equivalent time interval. Clinical significance was defined as a decrease in pain of 2 or more points following the education. RESULTS: Following the educational interventions, there were statistically significant, although not clinically significant, decreases in mean pain scores within each intervention group (video: mean change, 1 point [95% confidence interval [CI] = 0.7 to 1.2]; printed brochure: mean change, 0.6 points [95% CI = 0.4 to 0.8]). For participants in the control group (no intervention), there was no significant change (mean change, 0.2 points [95% CI = -0.2 to 0.5]). A clinically significant decrease in pain was seen in 28% of the video group, 23% of the brochure group, and 5% of controls. Most patients had no change (71% of the video group, 73% of the brochure group, and 89% of controls). Participants rated the helpfulness of the video educational intervention as 7.1 (95% CI = 6.7 to 7.5) and the print educational intervention as 6.7 (95% CI = 6.2 to 7.1) on a scale from 0 (least effective) to 10 (most helpful). CONCLUSIONS: Among ED participants with pain, both educational interventions (video and printed brochure) resulted in statistically and clinically significant decreased self-reported pain scores by 2 or more points in 26% of participants compared with 5% of controls. The educational interventions were rated as helpful by participants, with no appreciable difference between the two intervention groups.

Comparison of oxycodone and hydrocodone for the treatment of acute pain associated with fractures: a double-blind, randomized, controlled trial.

BACKGROUND: Previous studies have demonstrated the efficacy of oxycodone and hydrocodone for the treatment of acute pain. However, to the best of the authors' knowledge, no previous reports have compared the efficacies of these commonly prescribed agents. OBJECTIVES: To compare the efficacies of oxycodone and hydrocodone for the treatment of acute pain associated with fractures in emergency department (ED) patients. METHODS: This prospective, double-blind, randomized, controlled trial was conducted at an urban trauma center with an annual census of 65,000. Eligible participants included ED patients over the age of 12 years with fractures who consented to participate. Subjects were randomized to receive either oxycodone (5 mg orally [po]) with acetaminophen, or hydrocodone (5 mg po) with acetaminophen. Measurements included demographic information; pain scores on a verbal numeric rating scale at baseline and at 30 and 60 minutes; vital signs at baseline and at 30 and 60 minutes; and adverse effects. Ninety-five-percent confidence intervals (95% CIs) constructed about means and proportions were used to assess differences between the oxycodone and hydrocodone groups in analgesic efficacy and side effects. RESULTS: Seventy-three subjects were randomized to receive oxycodone or hydrocodone. Sixty-seven subjects completed the ED study period (n = 35, oxycodone; n = 32, hydrocodone). There was no difference between the two groups in age, weight, gender, ethnicity, diagnoses, baseline pain scores, or vital signs. Patients in both groups had pain relief from baseline to 30 minutes (oxycodone mean change 3.7, 95% CI = 2.9 to 4.6; hydrocodone mean change 2.5, 95% CI = 1.7 to 3.3), and from baseline to 60 minutes (oxycodone mean change 4.4, 95% CI = 3.2 to 5.6; hydrocodone mean change 3.0, 95% CI = 2.1 to 3.9). There was no difference in pain between the patients treated with oxycodone and hydrocodone at 30 minutes (mean difference between groups -0.6, 95% CI = -1.8 to 0.5) or at 60 minutes (mean difference -0.5, 95% CI = -2.0 to 1.0). There was no difference between the groups in nausea, vomiting, itching, or drowsiness; however, the hydrocodone patients had a higher incidence of constipation (oxycodone 0%, hydrocodone 21%, difference in proportions 21%, 95% CI = 3% to 39% more with hydrocodone). CONCLUSIONS: Treatment with acetaminophen and either oxycodone, 5 mg po, or hydrocodone, 5 mg po, resulted in pain relief among ED patients with acute fractures, and there was no difference between the two agents at 30 and 60 minutes. Adverse effect profiles were similar, with the exception of a higher incidence of subsequent constipation with the use of hydrocodone. These results suggest that oxycodone and hydrocodone have similarly potent analgesic effects in the first hour of treatment for ED patients with acute fractures.