- Email: [email protected]
353: The Effect of Training In Emergency Pelvic Ultrasonography on Emergency Medicine Nurse Practitioner and Physician Assistant Knowledge
Research Forum Abstracts HMGB1 levels were determined using purified recombinant HMGB1 at various dilutions (5, 10, 25 ng) by Western blot analysis with a standard reference curve. UN-SCAN-IT Gel 6.1 software was used to digitize Western blots for quantitative analysis. Levels of 42 other cytokines were determined in a subset of septic shock patients by the Ray Bio® Human Cytokine Antibody Array 3. Nonparametric tests were used for statistical analysis. The difference in HMGB1 levels in healthy controls and sepsis patients at baseline was analyzed using the Mann-Whitney test. The difference in HMGB1 levels among the Sepsis status groups (SIRS/sepsis and severe sepsis/septic shock) was analyzed using the Wilcoxen Two-Sample Test. Results: 23 septic subjects and 8 control subjects were enrolled. The median age of all subjects was 53.5 years, 59.38% male. There were no mortalities in the sepsis case groups. There was a significant difference in HMGB1 levels between sepsis patients and healthy controls at baseline with median levels of 1000 ng/mL (160 5600 ng/mL) and 37 ng/mL (17.5 - 66 ng/mL) respectively (p⬍0.0130). At baseline, median values of the SIRS/sepsis groups and severe sepsis/septic shock groups were 990 ng/mL (270 - 4400 ng/mL) and 5600 ng/mL (1370 - 7000 ng/mL) respectively. 43% of septic patients had HMGB1 levels that directly correlated with clinical progression and convalescence. For two severe sepsis/septic shock patients with cytokine array data, early pro-inflammatory cytokines (TNF-␣, IL-1) were not present, although other sepsis surrogate markers (GRO, MCP-1, RANTES, IL-6) correlated well with HMGB1 levels at baseline and 72h. Levels of HMGB1 and GRO, MCP-1, RANTES, IL-6 were elevated at baseline compared to 72h. Conclusion: HMGB1 is present in high levels in septic patients presenting to the ED and correlates well with known sepsis biomarkers. This preliminary study suggests that HMGB1 may be a potential biomarker for sepsis severity as well as a clinically viable therapeutic target for septic patients presenting to the ED due to its persistence in serum over time.
350
Induction and Reversal of Hypothermia With an Esophageal Device In an Animal Model
Kulstad E, Waller D/Advocate Christ Medical Center, Chicago, IL; PreLabs, LLC, Oak Park, IL
Study Objectives: Induction of hypothermia (a 4°C decrease from baseline) is beneficial in certain situations (adult cardiac arrest and neonatal hypoxic ischemic encephalopathy, for example), while prevention of perioperative hypothermia is critical during most surgical procedures. Methods used to implement or prevent hypothermia typically require skin contact with blankets or pads, or intravascular access with catheter devices. We evaluated a prototype of a new esophageal device in a swine model, hypothesizing that the device could both induce and reverse hypothermia successfully. Methods: We performed this single-animal proof-of-concept study using a 70kg Yorkshire swine under an IACUC-approved protocol at Loyola University Medical Center. After acclimation, the swine was intravenously sedated, endotracheally intubated, and anesthetized with 2% inhalational isoflurane. Shivering was prevented with intravenous doses of pancuronium. The experimental device was placed in the esophagus and connected to an external heat exchange unit capable of operating in either a cooling or warming mode. Continuous cardiac monitoring was performed with a 3-lead EKG rhythm recording. Starting swine temperature was 37.8°C and room temperature was 22°C. Results: With the temperature of the coolant in the heat exchange unit set to 4°C, swine temperature decreased to 33.8°C (achieving the goal of a 4°C decrease) in 175 minutes, resulting in over 439 kJ of heat extracted. With the heat exchange unit then set to a warming mode (coolant set to 42°C), swine temperature increased from a starting point of 33.6°C to a temperature of 34.3°C at the termination point of the experiment (over a timeframe of 130 minutes), for a total of 205 kJ of heat transferred. Cardiac monitoring showed some bradycardia without ectopy, and histopathology of the esophagus after necropsy showed normal tissue without evidence of injury. Conclusions: A prototype of an esophageal temperature management device induced hypothermia effectively in a large swine model. Although warming also appears possible, complete reversal of hypothermia was not achieved in the timeframe of the experiment, indicating that longer device application and additional device modification may be required.
S114 Annals of Emergency Medicine
351
Can Ultrasonography of the Optic Nerve Sheath Be Used to Predict and Monitor Changes In Intracranial Pressure?
Butts C, Stevens A, Hue T, Mills L/Louisiana State University, New Orleans, LA; Univeristy of California, Davis, CA
Study Objective: We seek to determine if serial measurements of the diameter of the optic nerve sheath made by ultrasonography examination can reliably be used to monitor changes in intracranial pressure (ICP). Methods: A convenience sample of 16 patients identified in the emergency department (ED) as requiring placement of an invasive ICP monitor was chosen for this study. The study was performed in the ED of an urban teaching hospital with a yearly census of approximately 60,000. Using ultrasonography, serial measurements of the optic nerve sheath diameter were taken and recorded at 30-minute intervals following placement of the ICP monitor for the four hours, and a single measurement was made and recorded at both 24 and 48 hours. At each interval, the ICP as measured by the invasive ICP monitor was also recorded. Results: A significant relationship was found between the ultrasonography measurement of the optic nerve sheath and intracranial pressure as measured by invasive monitoring (right eye p⫽0.0001 and left eye p⬍0.001). Conclusion: There is a significant relationship between measurement of the optic nerve sheath and intracranial pressure. The strength of this relationship presents an opportunity to use ultrasonography of the optic nerve sheath diameter to predict changes and to monitor changes in intracranial pressure.
352
Limited Emergency Ultrasonography of the Urinary Tract Versus Bedside Dipstick Hematuria as a Screening Test for Uterolithiasis
Goett H, Costantino TG, Satz W/Temple University, Philadelphia, PA
Study Objectives: In patients with ureterolithiasis, hematuria has been shown to have a sensitivity of about 70% to 85% and has been used as a bedside screening test for the disease. Previous studies with emergency ultrasonography have utilized only the presence of hydronephrosis as a marker for ureterolithiasis with a sensitivity of about 80%. We sought to compare hematuria versus a limited emergency ultrasonography (EUS) evaluation of the urinary tract which included a look both for hydronephrosis as well as ureteral jets as a screening test for ureterolithiasis. Methods: This is a retrospective, case control study of all adult patients who received an EUS evaluation of the urinary tract, bedside dipstick hematuria testing, and a computed tomography (CT) scan of the abdomen at an urban, academic center between January 2008 and January 2009. Chart abstraction was performed on these patients and data was separated into those who had CT evidence of ureterolithiasis and those who did not. The primary endpoint was sensitivity of EUS versus hematuria. EUS was performed by emergency physicians who had been trained according to ACEP guidelines. The EUS was considered positive if either hydronephrosis or the absence of ureteral jets on color Doppler ultrasonography of the bladder over one minute was found. Data were analyzed using the Fisher Exact method. Results: There were 142 patients enrolled, of which 45 had ureterolithiasis by non-contrast CT scan. The median age was 46 years (range 20 - 95). Hematuria had a sensitivity of 0.82 (95% CI 0.68 to 0.92) while EUS had a sensitivity of 0.98 (95% CI 0.88 to 0.99) p⫽0.015, (OR 9.3; 95% CI 1.1 to 77.8). Hematuria had a specificity of 0.22 (95% CI 0.14 to 0.31) while EUS had a specificity of 0.26 (95% CI 0.17 to 0.35) p⫽0.30, (OR 1.32 95% CI 0.79 to 2.23). Hydronephrosis on ultrasonography alone had a sensitivity of 0.77 (95% CI 0.65 to 0.88) and a specificity of 0.84 (95% CI 0.70 to 0.93). Conclusion: A limited ultrasonography protocol combining a search for hydronephrosis with the absence of ureteral jets was a more sensitive test than bedside dipstick hematuria in screening for the presence of ureterolithiasis with equivalent specificity. Adding a one-minute look for ureteral jets to a limited renal ultrasonography looking for hydronephrosis increases the sensitivity to the point of being able to “rule out” kidney stones, but decreases the specificity.
353
The Effect of Training In Emergency Pelvic Ultrasonography on Emergency Medicine Nurse Practitioner and Physician Assistant Knowledge
Simons R, Agresta J, Adler D, Davis E, Svengsouk J/University of Rochester, Rochester, NY
Study Objective: We examined the effectiveness of an educational course in emergency pelvic ultrasonography for emergency medicine (EM) mid-level providers
Volume , . : September
Research Forum Abstracts (nurse practitioners and physician assistants). We hypothesized that our 6-hour training course would be an effective first step in introducing emergency pelvic ultrasonography into our mid-level provider (MLP) scope of practice by demonstrating an increase in the knowledge necessary to perform and apply emergency pelvic ultrasonography. Methods: This study utilized a single group pretest-posttest design. All EM MLPs at a tertiary care university hospital that were available for the 6-hour educational course were included. The course consisted of a 3-hour didactic session and a 3-hour hands-on laboratory session covering the physics, knobology, indications, acquisition of images, and clinical application of emergency pelvic ultrasonography. A fiftyquestion written examination was administered immediately before and after the course. The same examination was administered to a sample of EM attendings and residents that met departmental privileging criteria for emergency pelvic ultrasonography and served as a performance gold standard to which EM MLPs could be compared. Pretest and posttest scores were compared using a one-sided paired ttest to determine the effectiveness of the course. Posttest scores and gold standard scores were compared using a two-sided, two-sample t-test. Results: Twenty-one MLPs took the course. Six credentialed EM attendings and residents took the examination. The mean pretest percentage score was 67.5 (95% confidence interval 63.6 to 71.4). The mean posttest percentage score was 86.3 (95% confidence interval 83.2 to 89.4). The mean posttest score was significantly higher than the mean pretest score (p⬍0.001). The mean gold standard score was 88.7 (95% confidence interval 83.0 to 94.4). The mean posttest score was not significantly different from the mean gold standard score (p⫽0.49). Conclusions: Emergency medicine MLPs performed significantly better on the posttest, demonstrating an increase in emergency pelvic ultrasonography knowledge after the 6-hour educational course. Given the ability of MLPs to acquire this knowledge, as evidenced by an increase in posttest scores to a level comparable to credentialed providers, further study of MLP knowledge retention, skill in image acquisition, and clinical application of acquired images is warranted.
354
Is a Baker’s Cyst on Lower Extremity Ultrasonography a Risk Factor for Concomitant Deep Venous Thrombosis?
Datta A, Kapoor M, Conry S, Gupta S, Green J, Garg N, Swaby J, Chun Lema P/ NYHQ, Flushing, NY; New York Hospital Queens, Flushing, NY
Study Objective: It has been suggested that Baker’s cyst is a risk factor for deep venous thrombosis (DVT). Baker’s cyst and DVT may occasionally co-exist. Our primary objective is to determine the incidence of DVT in the presence of Baker’s cyst. Methods: This was a retrospective chart review. All patients who had a lower extremity ultrasonography performed were included in the study. This study was performed at an urban hospital with ⬎120,000 annual visits in the emergency department (ED). We reviewed the picture archiving and communication system (PACS) and identified patients who had lower extremity ultrasonography. The index ultrasonography was used for any patient who had multiple visits to the hospital. We stratified patients with DVT as diagnosed by lower extremity duplex sonography by the presence or absence of a Baker’s cyst. Chi-square and Fisher’s exact test were used for categorical data for statistical analysis. Results: We identified 1068 patients who had a lower extremity ultrasonography from July 2005 to January 2009. Median age of all patients was 71 years (IQR 54-82 years). 56% were female and 52% were White. Baker’s cyst was present in 329 patients [30.9% (95%CI 28.1-33.6%)] and DVT was present in 423 patients [39.6% (95%CI 36.7-42.5%)]. Twenty out of 329 patients with Baker’s cyst also had a DVT [6.1% (95%CI 3.5-8.7%)]. DVT was present in 402 of the 739 patients in the absence of a Baker’s cyst [54.6%(95%CI 50.9-58.1%)] (p⬍0.001). Conclusion: Patients with a Baker’s cyst diagnosed on ultrasonography were less likely to have a simultaneously diagnosed deep venous thrombosis in this cohort of adult patients who had a lower extremity ultrasonography performed.
355
Out–Of–Hospital Evaluation of Effusion, Pneumothorax, and Standstill: EMS and Point-OfCare Ultrasonography
Pierog JE, Zaia BE, Bhat SR, Johnson DA, Gharahbaghian L, Gilbert GH, Williams SR/Stanford University Medical Center Hospital and Clinics, Stanford, CA
Study Objectives: Ultrasonography is routinely used in Europe by physicians working in the out– of– hospital setting and has been shown to affect clinical
Volume , . : September
outcomes. In the United States, there are limited studies regarding out– of– hospital ultrasonography. Rapid field diagnosis of life-threatening conditions such as pericardial effusion and pneumothorax could be of great utility, especially when transport times are prolonged. Ability to verify cardiac standstill may affect the need for hospital transport. In this study we assessed the ability of emergency medical technicians (EMT) and paramedic students to accurately interpret heart and lung ultrasonography imaging. Methods: We tested certified EMTs and paramedics, as well as EMT and paramedic students actively enrolled in certified out– of– hospital training programs within Santa Clara and San Mateo counties. Participants completed a 10-minute pretest containing sonographic imaging of normal lung, normal cardiac activity without effusion, and three pathologic findings: pericardial effusion, cardiac standstill, and pneumothorax. They were then given a one-hour focused lecture on interpretation of US imaging. A post-test was given immediately following the lecture. A second posttest was given at one week to a subgroup of participants. Scores were analyzed in SPSS 11.0 (Chicago, IL) using paired t-tests; test images were validated utilizing current emergency physicians and residents. Results: We enrolled 57 out– of– hospital providers (49 male, mean age and SD 26.2 years ⫾ 7.0) consisting of 19 EMT students, 16 paramedic students, 18 certified EMTs, and 4 certified paramedics. 11 emergency physicians were given the pre- and post-tests with average scores of 98.9% and 99.4% respectively (p⫽0.341, 95% CI ⫺1.834 - 0.698). The mean total pre-test score among all out– of– hospital providers was 65.2% ⫾ 12.7% with a mean total post-test score of 91.1% ⫾ 7.9% (p⬍0.001, 95% CI ⫺0.30 - ⫺0.22). Scores significantly improved for all three modalities. Mean scores for cardiac standstill improved from 92.1% ⫾ 15.1% pre-test to 98.6% ⫾ 5.6% post-test (p⫽0.003, 95% CI ⫺0.11 - ⫺0.23); mean scores for pericardial effusion improved from 57.9% ⫾ 26.3% pre-test to 84.6% ⫾ 21.5% post-test (p⬍0.001, 95% CI ⫺0.35 - ⫺0.19); mean scores for pneumothorax increased from 55.5% ⫾ 20.9% pre-test to 90.6% ⫾ 9.82% post-test(p⬍0.001, 95% CI ⫺0.41 ⫺0.29). A second post-test was obtained one week later from 19 subjects. The mean total score for this subgroup increased for all modalities: pre-test 65.8% ⫾ 10.7%; immediate post-test 90.5% ⫾ 7.0% (p⬍0.001, 95% CI ⫺0.31 - ⫺0.19), second post-test 93.1% ⫾ 8.3% (p⬍0.001, 95% CI ⫺0.34 - ⫺0.21). There was no significant difference between immediate and one-week post-test (p⫽0.134, 95% CI ⫺0.1 - 0.01) for this subgroup. Conclusion: Our results show out– of– hospital providers, without previous ultrasonography education, are able to accurately identify images of cardiac standstill, pneumothorax and pericardial effusion.
356
Ultrasonography Evaluation of the Effect of Head Rotation on the Relationship of the Internal Jugular Vein and Carotid Artery
Merritt RL, Derr C, Zevallous E, Downs K, Land L, Lasseter M, Denittis D, Paula R/Univ of South Florida, Tampa, FL
Study Objectives: Previous studies have shown that when the internal jugular vein (IJV) is 46-90 degrees in relation to the carotid artery (CA) that safe cannulation of the vein would be difficult, if not impossible. Our goal was to further examine the anatomical relationships of the IJV and CA during head rotation to determine what head position would decrease the risk for CA puncture. Methods: This is a prospective study using a convenience sample of 100 emergency department patients. Patients were placed in Trendelenburg and the anatomic relationships of the right and left internal jugular veins and carotid arteries were recorded with head rotation at 0, 45, and 80 degrees. All images and measurements were obtained with a 10-5 MHz linear array transducer in the transverse orientation. A goniometer was used to determine the position of the internal jugular vein relative to the carotid artery. Using the center of the carotid artery as the horizontal axis 0 to ⫹180 degrees depicted the vein as superficial to the artery and 0 to ⫺180 degrees as deep to the artery. The data was then sorted by 45 degree increments and degree of head rotation. Patients who had the IJV in a 46-90 degree relationship to the CA were deemed to be in the high risk zone for CA puncture. Results: At 0 degrees of head rotation 10.1% of right IJVs (p⫽⬍0.001) and 19.1% of left IJVs (p⫽⬍0.001) were in the high risk zone. At 45 degrees of head rotation 16.1% of right IJVs (p⫽⬍0.001) and 24% of left IJVs (p⫽⬍0.001) were in the high risk zone. At 80 degrees rotation 24.2% of right IJVs (p⫽⬍0.001) and 39% of left IJVs (p⫽ ⬍0.001) were in the high risk zone. Finally, 3% of patients had reversal of the normal anatomy placing the CA superficial to the IJV.
Annals of Emergency Medicine S115
350
Induction and Reversal of Hypothermia With an Esophageal Device In an Animal Model
Kulstad E, Waller D/Advocate Christ Medical Center, Chicago, IL; PreLabs, LLC, Oak Park, IL
Study Objectives: Induction of hypothermia (a 4°C decrease from baseline) is beneficial in certain situations (adult cardiac arrest and neonatal hypoxic ischemic encephalopathy, for example), while prevention of perioperative hypothermia is critical during most surgical procedures. Methods used to implement or prevent hypothermia typically require skin contact with blankets or pads, or intravascular access with catheter devices. We evaluated a prototype of a new esophageal device in a swine model, hypothesizing that the device could both induce and reverse hypothermia successfully. Methods: We performed this single-animal proof-of-concept study using a 70kg Yorkshire swine under an IACUC-approved protocol at Loyola University Medical Center. After acclimation, the swine was intravenously sedated, endotracheally intubated, and anesthetized with 2% inhalational isoflurane. Shivering was prevented with intravenous doses of pancuronium. The experimental device was placed in the esophagus and connected to an external heat exchange unit capable of operating in either a cooling or warming mode. Continuous cardiac monitoring was performed with a 3-lead EKG rhythm recording. Starting swine temperature was 37.8°C and room temperature was 22°C. Results: With the temperature of the coolant in the heat exchange unit set to 4°C, swine temperature decreased to 33.8°C (achieving the goal of a 4°C decrease) in 175 minutes, resulting in over 439 kJ of heat extracted. With the heat exchange unit then set to a warming mode (coolant set to 42°C), swine temperature increased from a starting point of 33.6°C to a temperature of 34.3°C at the termination point of the experiment (over a timeframe of 130 minutes), for a total of 205 kJ of heat transferred. Cardiac monitoring showed some bradycardia without ectopy, and histopathology of the esophagus after necropsy showed normal tissue without evidence of injury. Conclusions: A prototype of an esophageal temperature management device induced hypothermia effectively in a large swine model. Although warming also appears possible, complete reversal of hypothermia was not achieved in the timeframe of the experiment, indicating that longer device application and additional device modification may be required.
S114 Annals of Emergency Medicine
351
Can Ultrasonography of the Optic Nerve Sheath Be Used to Predict and Monitor Changes In Intracranial Pressure?
Butts C, Stevens A, Hue T, Mills L/Louisiana State University, New Orleans, LA; Univeristy of California, Davis, CA
Study Objective: We seek to determine if serial measurements of the diameter of the optic nerve sheath made by ultrasonography examination can reliably be used to monitor changes in intracranial pressure (ICP). Methods: A convenience sample of 16 patients identified in the emergency department (ED) as requiring placement of an invasive ICP monitor was chosen for this study. The study was performed in the ED of an urban teaching hospital with a yearly census of approximately 60,000. Using ultrasonography, serial measurements of the optic nerve sheath diameter were taken and recorded at 30-minute intervals following placement of the ICP monitor for the four hours, and a single measurement was made and recorded at both 24 and 48 hours. At each interval, the ICP as measured by the invasive ICP monitor was also recorded. Results: A significant relationship was found between the ultrasonography measurement of the optic nerve sheath and intracranial pressure as measured by invasive monitoring (right eye p⫽0.0001 and left eye p⬍0.001). Conclusion: There is a significant relationship between measurement of the optic nerve sheath and intracranial pressure. The strength of this relationship presents an opportunity to use ultrasonography of the optic nerve sheath diameter to predict changes and to monitor changes in intracranial pressure.
352
Limited Emergency Ultrasonography of the Urinary Tract Versus Bedside Dipstick Hematuria as a Screening Test for Uterolithiasis
Goett H, Costantino TG, Satz W/Temple University, Philadelphia, PA
Study Objectives: In patients with ureterolithiasis, hematuria has been shown to have a sensitivity of about 70% to 85% and has been used as a bedside screening test for the disease. Previous studies with emergency ultrasonography have utilized only the presence of hydronephrosis as a marker for ureterolithiasis with a sensitivity of about 80%. We sought to compare hematuria versus a limited emergency ultrasonography (EUS) evaluation of the urinary tract which included a look both for hydronephrosis as well as ureteral jets as a screening test for ureterolithiasis. Methods: This is a retrospective, case control study of all adult patients who received an EUS evaluation of the urinary tract, bedside dipstick hematuria testing, and a computed tomography (CT) scan of the abdomen at an urban, academic center between January 2008 and January 2009. Chart abstraction was performed on these patients and data was separated into those who had CT evidence of ureterolithiasis and those who did not. The primary endpoint was sensitivity of EUS versus hematuria. EUS was performed by emergency physicians who had been trained according to ACEP guidelines. The EUS was considered positive if either hydronephrosis or the absence of ureteral jets on color Doppler ultrasonography of the bladder over one minute was found. Data were analyzed using the Fisher Exact method. Results: There were 142 patients enrolled, of which 45 had ureterolithiasis by non-contrast CT scan. The median age was 46 years (range 20 - 95). Hematuria had a sensitivity of 0.82 (95% CI 0.68 to 0.92) while EUS had a sensitivity of 0.98 (95% CI 0.88 to 0.99) p⫽0.015, (OR 9.3; 95% CI 1.1 to 77.8). Hematuria had a specificity of 0.22 (95% CI 0.14 to 0.31) while EUS had a specificity of 0.26 (95% CI 0.17 to 0.35) p⫽0.30, (OR 1.32 95% CI 0.79 to 2.23). Hydronephrosis on ultrasonography alone had a sensitivity of 0.77 (95% CI 0.65 to 0.88) and a specificity of 0.84 (95% CI 0.70 to 0.93). Conclusion: A limited ultrasonography protocol combining a search for hydronephrosis with the absence of ureteral jets was a more sensitive test than bedside dipstick hematuria in screening for the presence of ureterolithiasis with equivalent specificity. Adding a one-minute look for ureteral jets to a limited renal ultrasonography looking for hydronephrosis increases the sensitivity to the point of being able to “rule out” kidney stones, but decreases the specificity.
353
The Effect of Training In Emergency Pelvic Ultrasonography on Emergency Medicine Nurse Practitioner and Physician Assistant Knowledge
Simons R, Agresta J, Adler D, Davis E, Svengsouk J/University of Rochester, Rochester, NY
Study Objective: We examined the effectiveness of an educational course in emergency pelvic ultrasonography for emergency medicine (EM) mid-level providers
Volume , . : September
Research Forum Abstracts (nurse practitioners and physician assistants). We hypothesized that our 6-hour training course would be an effective first step in introducing emergency pelvic ultrasonography into our mid-level provider (MLP) scope of practice by demonstrating an increase in the knowledge necessary to perform and apply emergency pelvic ultrasonography. Methods: This study utilized a single group pretest-posttest design. All EM MLPs at a tertiary care university hospital that were available for the 6-hour educational course were included. The course consisted of a 3-hour didactic session and a 3-hour hands-on laboratory session covering the physics, knobology, indications, acquisition of images, and clinical application of emergency pelvic ultrasonography. A fiftyquestion written examination was administered immediately before and after the course. The same examination was administered to a sample of EM attendings and residents that met departmental privileging criteria for emergency pelvic ultrasonography and served as a performance gold standard to which EM MLPs could be compared. Pretest and posttest scores were compared using a one-sided paired ttest to determine the effectiveness of the course. Posttest scores and gold standard scores were compared using a two-sided, two-sample t-test. Results: Twenty-one MLPs took the course. Six credentialed EM attendings and residents took the examination. The mean pretest percentage score was 67.5 (95% confidence interval 63.6 to 71.4). The mean posttest percentage score was 86.3 (95% confidence interval 83.2 to 89.4). The mean posttest score was significantly higher than the mean pretest score (p⬍0.001). The mean gold standard score was 88.7 (95% confidence interval 83.0 to 94.4). The mean posttest score was not significantly different from the mean gold standard score (p⫽0.49). Conclusions: Emergency medicine MLPs performed significantly better on the posttest, demonstrating an increase in emergency pelvic ultrasonography knowledge after the 6-hour educational course. Given the ability of MLPs to acquire this knowledge, as evidenced by an increase in posttest scores to a level comparable to credentialed providers, further study of MLP knowledge retention, skill in image acquisition, and clinical application of acquired images is warranted.
354
Is a Baker’s Cyst on Lower Extremity Ultrasonography a Risk Factor for Concomitant Deep Venous Thrombosis?
Datta A, Kapoor M, Conry S, Gupta S, Green J, Garg N, Swaby J, Chun Lema P/ NYHQ, Flushing, NY; New York Hospital Queens, Flushing, NY
Study Objective: It has been suggested that Baker’s cyst is a risk factor for deep venous thrombosis (DVT). Baker’s cyst and DVT may occasionally co-exist. Our primary objective is to determine the incidence of DVT in the presence of Baker’s cyst. Methods: This was a retrospective chart review. All patients who had a lower extremity ultrasonography performed were included in the study. This study was performed at an urban hospital with ⬎120,000 annual visits in the emergency department (ED). We reviewed the picture archiving and communication system (PACS) and identified patients who had lower extremity ultrasonography. The index ultrasonography was used for any patient who had multiple visits to the hospital. We stratified patients with DVT as diagnosed by lower extremity duplex sonography by the presence or absence of a Baker’s cyst. Chi-square and Fisher’s exact test were used for categorical data for statistical analysis. Results: We identified 1068 patients who had a lower extremity ultrasonography from July 2005 to January 2009. Median age of all patients was 71 years (IQR 54-82 years). 56% were female and 52% were White. Baker’s cyst was present in 329 patients [30.9% (95%CI 28.1-33.6%)] and DVT was present in 423 patients [39.6% (95%CI 36.7-42.5%)]. Twenty out of 329 patients with Baker’s cyst also had a DVT [6.1% (95%CI 3.5-8.7%)]. DVT was present in 402 of the 739 patients in the absence of a Baker’s cyst [54.6%(95%CI 50.9-58.1%)] (p⬍0.001). Conclusion: Patients with a Baker’s cyst diagnosed on ultrasonography were less likely to have a simultaneously diagnosed deep venous thrombosis in this cohort of adult patients who had a lower extremity ultrasonography performed.
355
Out–Of–Hospital Evaluation of Effusion, Pneumothorax, and Standstill: EMS and Point-OfCare Ultrasonography
Pierog JE, Zaia BE, Bhat SR, Johnson DA, Gharahbaghian L, Gilbert GH, Williams SR/Stanford University Medical Center Hospital and Clinics, Stanford, CA
Study Objectives: Ultrasonography is routinely used in Europe by physicians working in the out– of– hospital setting and has been shown to affect clinical
Volume , . : September
outcomes. In the United States, there are limited studies regarding out– of– hospital ultrasonography. Rapid field diagnosis of life-threatening conditions such as pericardial effusion and pneumothorax could be of great utility, especially when transport times are prolonged. Ability to verify cardiac standstill may affect the need for hospital transport. In this study we assessed the ability of emergency medical technicians (EMT) and paramedic students to accurately interpret heart and lung ultrasonography imaging. Methods: We tested certified EMTs and paramedics, as well as EMT and paramedic students actively enrolled in certified out– of– hospital training programs within Santa Clara and San Mateo counties. Participants completed a 10-minute pretest containing sonographic imaging of normal lung, normal cardiac activity without effusion, and three pathologic findings: pericardial effusion, cardiac standstill, and pneumothorax. They were then given a one-hour focused lecture on interpretation of US imaging. A post-test was given immediately following the lecture. A second posttest was given at one week to a subgroup of participants. Scores were analyzed in SPSS 11.0 (Chicago, IL) using paired t-tests; test images were validated utilizing current emergency physicians and residents. Results: We enrolled 57 out– of– hospital providers (49 male, mean age and SD 26.2 years ⫾ 7.0) consisting of 19 EMT students, 16 paramedic students, 18 certified EMTs, and 4 certified paramedics. 11 emergency physicians were given the pre- and post-tests with average scores of 98.9% and 99.4% respectively (p⫽0.341, 95% CI ⫺1.834 - 0.698). The mean total pre-test score among all out– of– hospital providers was 65.2% ⫾ 12.7% with a mean total post-test score of 91.1% ⫾ 7.9% (p⬍0.001, 95% CI ⫺0.30 - ⫺0.22). Scores significantly improved for all three modalities. Mean scores for cardiac standstill improved from 92.1% ⫾ 15.1% pre-test to 98.6% ⫾ 5.6% post-test (p⫽0.003, 95% CI ⫺0.11 - ⫺0.23); mean scores for pericardial effusion improved from 57.9% ⫾ 26.3% pre-test to 84.6% ⫾ 21.5% post-test (p⬍0.001, 95% CI ⫺0.35 - ⫺0.19); mean scores for pneumothorax increased from 55.5% ⫾ 20.9% pre-test to 90.6% ⫾ 9.82% post-test(p⬍0.001, 95% CI ⫺0.41 ⫺0.29). A second post-test was obtained one week later from 19 subjects. The mean total score for this subgroup increased for all modalities: pre-test 65.8% ⫾ 10.7%; immediate post-test 90.5% ⫾ 7.0% (p⬍0.001, 95% CI ⫺0.31 - ⫺0.19), second post-test 93.1% ⫾ 8.3% (p⬍0.001, 95% CI ⫺0.34 - ⫺0.21). There was no significant difference between immediate and one-week post-test (p⫽0.134, 95% CI ⫺0.1 - 0.01) for this subgroup. Conclusion: Our results show out– of– hospital providers, without previous ultrasonography education, are able to accurately identify images of cardiac standstill, pneumothorax and pericardial effusion.
356
Ultrasonography Evaluation of the Effect of Head Rotation on the Relationship of the Internal Jugular Vein and Carotid Artery
Merritt RL, Derr C, Zevallous E, Downs K, Land L, Lasseter M, Denittis D, Paula R/Univ of South Florida, Tampa, FL
Study Objectives: Previous studies have shown that when the internal jugular vein (IJV) is 46-90 degrees in relation to the carotid artery (CA) that safe cannulation of the vein would be difficult, if not impossible. Our goal was to further examine the anatomical relationships of the IJV and CA during head rotation to determine what head position would decrease the risk for CA puncture. Methods: This is a prospective study using a convenience sample of 100 emergency department patients. Patients were placed in Trendelenburg and the anatomic relationships of the right and left internal jugular veins and carotid arteries were recorded with head rotation at 0, 45, and 80 degrees. All images and measurements were obtained with a 10-5 MHz linear array transducer in the transverse orientation. A goniometer was used to determine the position of the internal jugular vein relative to the carotid artery. Using the center of the carotid artery as the horizontal axis 0 to ⫹180 degrees depicted the vein as superficial to the artery and 0 to ⫺180 degrees as deep to the artery. The data was then sorted by 45 degree increments and degree of head rotation. Patients who had the IJV in a 46-90 degree relationship to the CA were deemed to be in the high risk zone for CA puncture. Results: At 0 degrees of head rotation 10.1% of right IJVs (p⫽⬍0.001) and 19.1% of left IJVs (p⫽⬍0.001) were in the high risk zone. At 45 degrees of head rotation 16.1% of right IJVs (p⫽⬍0.001) and 24% of left IJVs (p⫽⬍0.001) were in the high risk zone. At 80 degrees rotation 24.2% of right IJVs (p⫽⬍0.001) and 39% of left IJVs (p⫽ ⬍0.001) were in the high risk zone. Finally, 3% of patients had reversal of the normal anatomy placing the CA superficial to the IJV.
Annals of Emergency Medicine S115