ED Ultrasound Rob Hall MD Oral Presentation PGY4 Emergency Medicine October 30 th, 2003

ED echo ( Eddie ) ED ultrasound WHY SHOULD WE?

Ultrasound imaging enhances the physician's ability to evaluate, diagnose, and treat emergency department (ED) patients. Because ultrasound imaging is often time- dependent in the acutely ill or injured patient, the emergency physician is in an ideal position to use this technology. Focused ultrasound examinations provide immediate information and can answer specific questions about the patient's physical condition. Such bedside ultrasound imaging is within the scope of practice of emergency physicians.

CAEP Position Statement: Feb 1999 Ultrasound should be available 24 hours per day for emergency patients, particularly for those being evaluated for cardac tamponade, abdominal aortic aneurysm, abdominal trauma, and ectopic pregnancy. A focused or limited bedside Emergency Department ultrasound should be available, performed by technicians, radiologists, or appropriately trained, qualified and experienced Emergency Physicians.

Who is doing ED ultrasound in the USA? Counselman. Acad Emerg Med 2000 Mail out survery 80% response rate 95% of emergency medicine training programs teaching and using ultrasound Accounting for response bias % of programs Conclusion: ED ultrasound is mainstay in US emerg programs

What do all these places have in common? Winnipeg Lethbridge Kelowna Lillooet Abbotsford Vancouver Victoria Nanaimo Fredericton Sacre Coeur Granby St-Paul Monmagny Montreal Ottawa Torondo Windsor Brampton Sarnia Kingston Parry Sound Huntsvile Sault Sainte Marie

What do all of these specialists have in common?

Main objective: literature review of ED ultrasound 4 Primary Indications AAA CardiacFAST Pregnancy

Main objective: literature review of ED ultrasound 4 Primary Indications AAA CardiacFAST Pregnancy

AAA: objectives Is there literature supporting ED ultrasound to detect AAAs? How much training is required be accurate?

AAA: general information Ultrasound done by radiology is nearly 100% sensitive for the detection of AAA Ultrasound measurements correlate with CT and laparotomy measurements w/I 2-3mm Physical examination is unreliable: Lederle JAMA cm29% sensitivity cm50% sensitivity > 5.0cm75% sensitivity

AAA: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Jones 2003 N=668hrs98 (86-100) 100 (87-100) 99 (90-100) Rowland 2001 N=333 days100 (74-100) 100 (85-100) 100 (90-100) Kuhn 2000 N=683 days100 (87-100) 100 (91-100) 100 Mandavia 2000 N=4416hrs50 (15-70) 95 (79-98) 93 Lanoix 2000 N=204hrs100 (40-100) 100 (76-100) 100 Schlager 95 N=1116hrs100

AAA: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Jones 2003 N=668hrs98 (86-100) 100 (87-100) 99 (90-100) Rowland 2001 N=333 days100 (74-100) 100 (85-100) 100 (90-100) Kuhn 2000 N=683 days100 (87-100) 100 (91-100) 100 Mandavia 2000 N=4416hrs50 (15-70) 95 (79-98) 93 Lanoix 2000 N=204hrs100 (40-100) 100 (76-100) 100 Schlager 95 N=1116hrs100

AAA Jones. Emergency Medicine Prospective N=66 scans for AAA Initial training was an 8 hour course covering four primary indications Gold standard = CT or laparotomy Results Sensitivity 98% (86-100) Specificity 100% (87-100) Accuracy 99% (90-100)

AAA Khun. Ann Emerg Med 2000 Prospective, N=68 Training was 3 days (2hrs for AAA) Gold standard = radiologist review of video Results Sensitivity 100% (87-100) Specificity 100% (91-100) Accuracy 100% (no CI)

AAA: conclusions Emergency Physicians can achieve accuracy in detection of AAAs with limited training Our scans should aim to be 95% accurate

Main objective: literature review of ED ultrasound 4 Primary Indications AAA CardiacFAST Pregnancy

Cardiac: objectives Can ED ultrasound be used to predict survival post cardiac arrest? Is there literature supporting ED ultrasound for the detection of pericardial effusions? LV function?

Cardiac arrest and ED ultrasound Blaivas Acad Emerg Med 2001 Prospective, N=166 Cardiac standstill 0/136 survival Cardiac activity 20/33 survival Salen Acad Emerg Med 2001 Prospective, N=102 Standstill: 2/61 survival Cardiac activity: 11/41 survival ETC02 production was a better predictor

Cardiac: conclusions There is insufficient evidence to prove that cardiac standstill is a reliable indicator of cardiac arrest survival Cardiac standstill should be considered in the decision to terminate resuscitation but should not be the sole criterion

Cardiac: LV function Moore. Acad Emerg Med 2002 Looked at atraumatic hypotensive patients Prospective, N=51, cardiology as gold standard Ratings: normal (1), mod depressed (2), severely depressed (3) Kappa 0.61 ( ) EP ratings Cardiologist ratings

Cardiac: pericardial effusions StudyMethodTrainingSensSpecAccurac y Mandavia 2001 N=51516hrs96 (90-99) 98 (96-99) 97.5 (95-99) Mandavia 2000 N = 2816hrs100 (50-100) 100 (60-100) 100 Lanoix 2000 N=674hrs88 (47-99) 98 (90-99) 97 Ma 1995N=24510hrs + 20 exams 10099

Cardiac: pericardial effusions StudyMethodTrainingSensSpecAccurac y Mandavia 2001 N=51516hrs96 (90-99) 98 (96-99) 97.5 (95-99) Mandavia 2000 N = 2816hrs100 (50-100) 100 (60-100) 100 Lanoix 2000 N=674hrs88 (47-99) 98 (90-99) 97 Ma 1995N=24510hrs + 20 exams 10099

Cardiac: pericardial effusions Mandavia. Ann Emerg Med 2001 Prospective study, N=515 Training = 16hrs, 5hrs dedicated to echo Gold standard = blinded cardiologist interpretation All scans were clinically indicated Results: Technically adequate in 93% Sensitivity 96% (90-99) Specificity 98% (96-99) Accuracy 97.5% (95-99)

Cardiac: conclusions Emergency Physicians can achieve accuracy in detection of pericardial effusion with limited training Our scans should aim to be 95% accurate Determination of LV function requires further study

Main objective: literature review of ED ultrasound 4 Primary Indications AAA CardiacFAST Pregnancy

Pregnancy: objectives How does ED ultrasound affect patient satisfaction? How does ED ultrasound affect ED flow? Is there literature supporting the accuracy of ED ultrasound in pregnancy?

Pregnancy: patient satisfaction Krubel. Am J Emerg Med Prospective; ½ got ED ultrasound Survey of 96 ED visits Showed Improved overall satisfaction with ED care Improved satisfaction with tests performed Reduced desire for a second opinion Reduced anxiety after the ED visit

Pregnancy: ED flow Remember the chart review we did last year: pregnancy related u/s Document IUP was found in 72% of initial ultrasounds ED ultrasound would likely be useful in 72% of patients

Pregnancy: ED flow Rogerson. Acad Emerg Med ED RUQ ultrasound is associated with a reduced time to diagnosis and treatment of rupture ectopic pregnancies Retrospective review TimeED u/sRadiology u/s To Dx58 min (28-87)197 ( ) To OR111 min (69-153)322 ( )

Pregnancy: ED flow Blaivas. Acad Emerg Med 2000 Do emergency physicians save time when locating a live IUP with bedside ultrasound? Retrospective review of 1419 charts Length of stays ED ultrasound3hr 40min Rad ultrasound4hr 39min Absolute diff59 min, p=0.0001

Pregnancy: ED flow Burgher. Acad Emerg Med 1998 Before and after ED u/s introduction study Mean L.O.S. before: 234 min Mean L.O.S. after: 164 min Difference 70 min, p= Shih. Ann Emerg Med Prospective; L.O.S. decreased when ultrasound showed an IUP ED ultrasound: mean L.O.S. 45 min Radiology ultrasound: mean L.O.S. 177min

Pregnancy: conclusions ED ultrasound can improve ED flow ED ultrasound can improve patient satisfaction

Pregnancy: detecting an IUP How accurate can ER docs be after minimal training? Is it safe?

Pregnancy: detecting and IUP Studies look at sensitivity and specificity of detecting an IUP not an ectopic Specificity is therefore more important! IUP present IUP absent U/S shows IUP True Positive False Positive (BAD!!!!!!) U/S doesn t show IUP False Negative True Negative

Pregnancy: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Mandavia 2000 N=10116 hrs76 (61-99) 92 (76-96) 83% Lanoix 2000 N=334hrs100 (82-100) 90 ( ) 97% Shih 1997 N=12524hrs +10exams 94% (82-98%) 100 (83-100) 96% Durham 1997 N=13624hrs + 10 exams 97% (91-97) Mateer 1995 N=15212hrs + 12 exams 99 (97-100) 93 (80-100) Jehle 1989N=40??97.5

Pregnancy: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Mandavia 2000 N=10116 hrs76 (61-99) 92 (76-96) 83% Lanoix 2000 N=334hrs100 (82-100) 90 ( ) 97% Shih 1997 N=12524hrs +10exams 94% (82-98%) 100 (83-100) 96% Durham 1997 N=13624hrs + 10 exams 97% (91-97) Mateer 1995 N=15212hrs + 12 exams 99 (97-100) 93 (80-100) Jehle 1989N=40??97.5

Pregnancy: detecting an IUP Shih. Ann Emerg Med 1997 Prospective, N=125 Training: 24hrs + 10 proctored exams Gold standard was formal ultrasound Some were transvag some transabd Results Sensitivity for IUP: 94% (C.I %) Specificity for IUP: 100% (C.I )

Pregnancy: detecting an IUP Durham. Ann Emerg Med 1997 Prospective, N=136 Training: 24hrs + 20 proctored exams (variable) Gold standard: formal ultrasound Pre-defined possible ultrasound results and correlated ER interpretation vs formal ultrasound result Results showed overall 97% accurracy (91-97% C.I.)

Pregnancy: detecting an IUP: Durham. Ann Emerg Med 1997 DiagnosisCorrectIncorrectAccuracy (95%C.I.) IUP with fetal pole % (97-100) IUP <6wks9375% (59-93) Indeterminate150100% (82-100) Ectopic7188% (60-95) Bl. Ovum20 Molar10 Totals121497% (91-97)

Pregnancy: detecting an IUP Mateer. Acad Emerg Med Prospective, N=152 Training: 12hrs + 12 proctored exams Gold standard: interpretation by gyne Also looked at results compared to final outcome ER interpretation versus gyne interpretation Correct 94% Incorrect 4.7% Inadequate 1.4%

Pregnancy: conclusions Emergency physicians can accurately detect Intra-uterine pregnancy Our scans should aim to be 95% accurate Specificity for IUP needs to be 100% If you re not sure it s an IUP, call it a NO definitive IUP and get a formal ultrasound

Main objective: literature review of ED ultrasound 4 Primary Indications AAA CardiacFAST Pregnancy

FAST: objectives What is the learning curve for FAST? Can surgeons use FAST accurately? Can emergency physicians use FAST accurately?

FAST: general comments Sensitivity is very dependant on the gold standard FAST done by RADIOLOGISTS Laparotomy as gold standard Sensitivties 93-97% Specificities % CT as gold standard Sensitivity 89% Specificity 99%

FAST: variable sensitivity Melanson. Emerg Med Clinics 1998 Reviewed 30+ studies Summarized studies with > 250 scans Sensitivities ranged from 70-99% Specificities ranged from 95-99%

FAST: variable sensitivity Branney. J. Trauma Used CAPD patients and looked at sensitivity with various volumes of dialysate FAST sensitivity clearly varies with volume of intraperitoneal fluid

FAST: learning curves Gracias. American Surgeon: showed correlation of sensitivity with experience Minimal (<30exams): sensitivity 59% Moderate (30-100): sensitivity 88% Extensive (>100): sensitivity 100% Shackford. J Trauma Prospective, N=241 Surgeons with 8hr training and 10 supervised exams Gold standard problems

FAST learning curves: Shackford 1999 Error rates

FAST: surgeons Rozycki. J Trauma Prospective, N=476 32hour training (some had more) Gold standard problems: CT, lap, DPL, or serial exams!!!! Sensitivity 79%, Specificity 96%, Accuracy 92% Compared to radiology review of still images Accuracy 90%, 5% technically inadequate

FAST: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Mandavia 2000 N=19816 hrs86 (61-93) 100 (94-100) 97 Lanoix 2000 N=444hrs94 (68-97) 93 (75-99) 93 Jones 2003 N=122unclear ?8hrs 72 (53-86) 97 (91-99) 90 (83-95) Rowland 2001 N=663 days64 (31-89) 85 (73-94) 82 (70-90) Ma 1995 N=24510hr +20 exams Vassiliadis 2003 N=140variable70 (58-97)98 (95-100)91 (86-96)

FAST: 6 prospective studies StudySizeTrainingSens. % (C.I.s) Spec.% (C.I.s) Accurracy (C.I.s) Mandavia 2000 N=19816 hrs86 (61-93) 100 (94-100) 97 Lanoix 2000 N=444hrs94 (68-97) 93 (75-99) 93 Jones 2003 N=122unclear ?8hrs 72 (53-86) 97 (91-99) 90 (83-95) Rowland 2001 N=663 days64 (31-89) 85 (73-94) 82 (70-90) Ma 1995 N=24510hr +20 exams Vassiliadis 2003 N=140variable70 (58-97)98 (95-100)91 (86-96)

FAST: emergency physicians Mandavia. Acad Emerg Med 2000 Prospective, total N=1138, FAST N=198 Training = 16 hr session Gold standard = over-read by ED physician with extensive ultrasound training Results Sensitivity 86% (61-93) Specificity 100% (94-100) Accuracy 97%

FAST: emergency physicians Ma. J Trauma Prospective, N=245 Training = 10 hrs + 20 exams Gold standard problems: CT, DPL, lap, clinical observation Also had surgical sonographer overread Results: sensitivity 86%, specificity 99%, accuracy 98% (NO confidence intervals) Compared to surgical sonographer : agreement with ER interpretation in 95%

FAST: conclusions FAST likely takes longer to learn Emergency physicians can achieve high specificity FAST done by Radiology is approximately 90% sensitive Emergency physicians have been shown to be accurate when interpretation is compared to experienced ultrasonographer Emergency physicians have NOT been shown to achieve high sensitivity INTERPRET A NEGATIVE SCAN WITH CAUTION!!

Final Recomendations SAEM/CAEP guidelines Training of an introductory course + 50 proctored exams is reasonably supported by the literature FAST may be the one exception: we should consider further training in FAST Targets for our scans Accurracy 95% Technically limited scans < 5-10% High specificity four all four primary indications > be aware of this …….

Final Recommendations Pregnany Definitive IUP r/o ectopic No definitive IUP get a formal u/s No AAA scan if still suspicious No effusion echo if still suspicious No free fluid CT scan when stable

Questions? Comments?