- Email: [email protected]
56 Accuracy of Emergency Physician-Performed Transthoracic Echocardiography in the Evaluation of the Thoracic Aorta
Research Forum Abstracts and Nexfin CI measurements was r ⫽ 0.33 with a percentage difference of 40.8%. Similarly, CI measured by the echocardiographer compared to Nexfin CI showed r ⫽ 0.56, and 39.5% difference. The correlation in CI measurements obtained by the emergency physician compared to echocardiographer showed r ⫽ 0.71 and 4.8% difference. Bland-Altman analysis of Nexfin compared to emergency physician ultrasound CI showed a bias (limits of agreement) of 1.00 (-0.92 to 2.92) L/min/m2. CI measured by emergency physician compared to echocardiographer showed a bias (limits of agreement) of -0.03 (-0.80 to 0.74) L/min/m2. Conclusion: Cardiac index is measurable in the ED setting using standard ultrasound technology with moderate correlation between emergency physicians and certified echocardiographer. However, CI measurements by ultrasound underestimate those obtained by pulse contour analysis.
56
Accuracy of Emergency Physician-Performed Transthoracic Echocardiography in the Evaluation of the Thoracic Aorta
Taylor RA, Van Tonder R, Oliva I, Dziura J, Moore CL/Yale University, New Haven, CT
Study Objectives: Thoracic aortic aneurysm (TAA) and thoracic aortic dissection (TAD) are related and potentially deadly diseases that present with nonspecific symptoms. Transthoracic echocardiography (TTE) may detect thoracic aortic pathology and is being increasingly performed by the emergency physician at the bedside; however, the potential accuracy of emergency physician ultrasound for TAA and TAD has not been studied. The objective of this study was to determine the agreement, sensitivity, and specificity of emergency physician TTE for thoracic aortic dimensions, dilation, and aneurysm with CT angiography as the reference standard. Methods: Prospective analysis of previously acquired images on consecutive patients presenting to an urban, academic ED with over 70,000 annual visits between 1/2008 and 6/2010 who had both an emergency physician-performed TTE and CTA for suspicion of thoracic aorta pathology. Thoracic aorta dimensions were measured from recordings by 3 ultrasound-trained emergency physicians blinded to any initial TTE and CTA results. CTA measurements were obtained by a radiologist blinded to the TTE results. Using cutoffs of 40 mm and 45 mm, we calculated the sensitivity and specificity of emergency physician TTE for aortic dilation and aneurysm with the largest measurement on CT as the reference standard. Bland-Altman plots and Pearson’s correlation coefficients were prepared to demonstrate agreement for aortic measurements, kappa statistics to assess the degree of agreement between tests for aortic dilation, and intraclass correlation for interobserver and intraobserver variability. Results: 92 patients underwent both emergency physician-performed TTE and CTA during the study period. 10 TTE studies had inadequate visualization for measurements. 82 patients were included in the final analysis. Mean age was 58.1(16.6) and 58.5% were male. 29 patients had thoracic aortic dilation on either TTE or CTA, 23 of which were seen on TTE. 3 out of 6 aortic dilations seen on CT and not TEE were descending aortic dilations without adequate views on TTE. Sensitivity, specificity and the observed kappa value (95%CI) between TTE and CTA
for the presence of aortic dilation at the 40 mm cutoff were 0.77(0.58-0.98), 0.95 (0.84-0.99), and 0.74(0.58-0.90) respectively. The intraclass correlation between observers for TTE measurements was 0.89 and for intraobserver variability was 0.95. The mean difference (95% limits of agreement) for the Bland Altman plots was 0.6 mm (-5.3-6.5) for the sinuses of Valsalva, 4 mm (-2.7-10.7) for the sinotubular junction, 1.5 mm (-5.8-8.8) for the ascending aorta, and 2.2 mm (-5.9-10.3) for the descending aorta. Conclusion: In this prospective analysis of previously acquired images, emergency physician-performed TTE was in good agreement for aortic dilation, aortic aneurysm, and ascending thoracic aortic dimensions and was specific for aortic dilation and aneurysm when compared to CTA.
57
Are Research Participants Truly Informed? Changes in Readability of Informed Consent Over Time
Penny AE, Foster L, Robinson KR, Sutliffe C, Jones JS/Spectrum Health System, Michigan State University College of Human Medicine, Grand Rapids, MI
Study Objectives: Informed consent documents present highly complex information that must be understood by research subjects. This complexity is a major barrier to comprehension for the approximately 1 quarter of American adults with low literacy skills. The purpose of this study is to determine average reading grade levels for informed consent forms submitted to the institution review board of an academic health system during 2009-10. This readability analysis will be compared to results from a similar study performed at our health system in 1993-4. Methods: A retrospective cohort study of informed consent forms submitted to the institution review board of an academic health system, a collection of 9 hospitals and 170 service sites, during a 2-year study period (2009-2010). Documents were computer analyzed for readability using the Flesch reading ease score and the FleschKincaid grade level. Both formulas have been examined in validation studies and used in other studies to evaluate readability of consent forms. Comparisons between groups were performed by Student’s t-test or 1-way analysis of variance (when multiple comparisons were made). Results: A total of 185 consent forms representing 18 medical specialties were evaluated. The majority of the informed consent forms were submitted by medical subspecialities, followed by pediatrics (36), orthopedics (17), surgical specialties (12), emergency medicine (9), and Ob-Gyn (7). The mean Flesch grade level ranged from the 8th to the 12th grade. The overall mean grade level was 9.8 ⫹ 1.2. Overall, 49 informed consent forms (26%) were written at the 8th-grade reading level, which is the recommended reading level for consent documentation. The reading grade levels did not differ significantly between medical specialties, informed consent forms page length, type of funding (intramural vs. extramural), or risk to the subject. Pediatric studies had a Flesch grade level of 9.7, while adult studies had a mean grade level of 10.3 (p ⬍.001). Compared to a readability analysis at our institution in 1993-4, current reading ease scores for consent documentation were significantly less complex (44.8 vs. 54.3, p ⬍.001). However, consent documentation has increased from 7 to 13 pages (86%). Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task, rarely accomplished at the time of institutional review board submission. Medical investigators should strive to simplify informed consent forms and to develop new methods for instructing those for whom current written documents have no meaning. Improvements have been made in readability of informed consent forms at our academic center during the past 16 years. However, the length of consent forms has also significantly increased.
58
Factors Determining Patient Willingness to Participate in Clinical Research Studies in the Emergency Department: A Pilot Study
Woodyard DJ, Shofer F, Prabhakar P, Howard K, Felton A, Hobgood CD/University of North Carolina, Chapel Hill, NC; Indiana University, Indianapolis, IN
Study Objectives: The array of patients and clinical conditions presenting to emergency departments provide a diverse population for clinical research, however, patients in the emergency department (ED) have been identified as less willing to participate in clinical trials. This study seeks to clarify some of the factors that may influence ED patients’ decisions to participate in clinical studies. Methods: We used a stratified survey methodology to examine variables we postulated would influence a patient’s decision to enroll in research studies. We
S196 Annals of Emergency Medicine
Volume , . : October
56
Accuracy of Emergency Physician-Performed Transthoracic Echocardiography in the Evaluation of the Thoracic Aorta
Taylor RA, Van Tonder R, Oliva I, Dziura J, Moore CL/Yale University, New Haven, CT
Study Objectives: Thoracic aortic aneurysm (TAA) and thoracic aortic dissection (TAD) are related and potentially deadly diseases that present with nonspecific symptoms. Transthoracic echocardiography (TTE) may detect thoracic aortic pathology and is being increasingly performed by the emergency physician at the bedside; however, the potential accuracy of emergency physician ultrasound for TAA and TAD has not been studied. The objective of this study was to determine the agreement, sensitivity, and specificity of emergency physician TTE for thoracic aortic dimensions, dilation, and aneurysm with CT angiography as the reference standard. Methods: Prospective analysis of previously acquired images on consecutive patients presenting to an urban, academic ED with over 70,000 annual visits between 1/2008 and 6/2010 who had both an emergency physician-performed TTE and CTA for suspicion of thoracic aorta pathology. Thoracic aorta dimensions were measured from recordings by 3 ultrasound-trained emergency physicians blinded to any initial TTE and CTA results. CTA measurements were obtained by a radiologist blinded to the TTE results. Using cutoffs of 40 mm and 45 mm, we calculated the sensitivity and specificity of emergency physician TTE for aortic dilation and aneurysm with the largest measurement on CT as the reference standard. Bland-Altman plots and Pearson’s correlation coefficients were prepared to demonstrate agreement for aortic measurements, kappa statistics to assess the degree of agreement between tests for aortic dilation, and intraclass correlation for interobserver and intraobserver variability. Results: 92 patients underwent both emergency physician-performed TTE and CTA during the study period. 10 TTE studies had inadequate visualization for measurements. 82 patients were included in the final analysis. Mean age was 58.1(16.6) and 58.5% were male. 29 patients had thoracic aortic dilation on either TTE or CTA, 23 of which were seen on TTE. 3 out of 6 aortic dilations seen on CT and not TEE were descending aortic dilations without adequate views on TTE. Sensitivity, specificity and the observed kappa value (95%CI) between TTE and CTA
for the presence of aortic dilation at the 40 mm cutoff were 0.77(0.58-0.98), 0.95 (0.84-0.99), and 0.74(0.58-0.90) respectively. The intraclass correlation between observers for TTE measurements was 0.89 and for intraobserver variability was 0.95. The mean difference (95% limits of agreement) for the Bland Altman plots was 0.6 mm (-5.3-6.5) for the sinuses of Valsalva, 4 mm (-2.7-10.7) for the sinotubular junction, 1.5 mm (-5.8-8.8) for the ascending aorta, and 2.2 mm (-5.9-10.3) for the descending aorta. Conclusion: In this prospective analysis of previously acquired images, emergency physician-performed TTE was in good agreement for aortic dilation, aortic aneurysm, and ascending thoracic aortic dimensions and was specific for aortic dilation and aneurysm when compared to CTA.
57
Are Research Participants Truly Informed? Changes in Readability of Informed Consent Over Time
Penny AE, Foster L, Robinson KR, Sutliffe C, Jones JS/Spectrum Health System, Michigan State University College of Human Medicine, Grand Rapids, MI
Study Objectives: Informed consent documents present highly complex information that must be understood by research subjects. This complexity is a major barrier to comprehension for the approximately 1 quarter of American adults with low literacy skills. The purpose of this study is to determine average reading grade levels for informed consent forms submitted to the institution review board of an academic health system during 2009-10. This readability analysis will be compared to results from a similar study performed at our health system in 1993-4. Methods: A retrospective cohort study of informed consent forms submitted to the institution review board of an academic health system, a collection of 9 hospitals and 170 service sites, during a 2-year study period (2009-2010). Documents were computer analyzed for readability using the Flesch reading ease score and the FleschKincaid grade level. Both formulas have been examined in validation studies and used in other studies to evaluate readability of consent forms. Comparisons between groups were performed by Student’s t-test or 1-way analysis of variance (when multiple comparisons were made). Results: A total of 185 consent forms representing 18 medical specialties were evaluated. The majority of the informed consent forms were submitted by medical subspecialities, followed by pediatrics (36), orthopedics (17), surgical specialties (12), emergency medicine (9), and Ob-Gyn (7). The mean Flesch grade level ranged from the 8th to the 12th grade. The overall mean grade level was 9.8 ⫹ 1.2. Overall, 49 informed consent forms (26%) were written at the 8th-grade reading level, which is the recommended reading level for consent documentation. The reading grade levels did not differ significantly between medical specialties, informed consent forms page length, type of funding (intramural vs. extramural), or risk to the subject. Pediatric studies had a Flesch grade level of 9.7, while adult studies had a mean grade level of 10.3 (p ⬍.001). Compared to a readability analysis at our institution in 1993-4, current reading ease scores for consent documentation were significantly less complex (44.8 vs. 54.3, p ⬍.001). However, consent documentation has increased from 7 to 13 pages (86%). Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task, rarely accomplished at the time of institutional review board submission. Medical investigators should strive to simplify informed consent forms and to develop new methods for instructing those for whom current written documents have no meaning. Improvements have been made in readability of informed consent forms at our academic center during the past 16 years. However, the length of consent forms has also significantly increased.
58
Factors Determining Patient Willingness to Participate in Clinical Research Studies in the Emergency Department: A Pilot Study
Woodyard DJ, Shofer F, Prabhakar P, Howard K, Felton A, Hobgood CD/University of North Carolina, Chapel Hill, NC; Indiana University, Indianapolis, IN
Study Objectives: The array of patients and clinical conditions presenting to emergency departments provide a diverse population for clinical research, however, patients in the emergency department (ED) have been identified as less willing to participate in clinical trials. This study seeks to clarify some of the factors that may influence ED patients’ decisions to participate in clinical studies. Methods: We used a stratified survey methodology to examine variables we postulated would influence a patient’s decision to enroll in research studies. We
S196 Annals of Emergency Medicine
Volume , . : October