Residents should not independently perform focused abdominal sonography for trauma after 10 training examinations

Hands-On Time in Simulation-Based Ultrasound Training - A Dose-Related Response Study

Purpose Point of care ultrasound (POCUS) is widely used, but the sensitivity and specificity of the findings are highly user-dependent. There are many different approaches to ultrasound training. The aim of this study was to explore the effects of hands-on practice when learning POCUS. Methods Junior doctors with no or limited ultrasound experience were included in the study and divided into three groups. They all completed a Focused Assessment with Sonography for Trauma (FAST) course with different amounts of hands-on practice: 40 minutes (n=67), 60 minutes (n=12), and 90 minutes of hands-on time (n=27). By the end of the course, they all completed a previously validated test. Results More hands-on time improved the mean test scores and decreased the test time. The scores of the 40-, 60-, and 90-minute groups were 11.6 (SD 2.1), 12.8 (SD 2.5), and 13.7 (SD 2.5), respectively (p<0.001). The 90-minute group completed the test significantly faster than the other two groups (20 versus 26 minutes, p=0.003). A large inter-individual variation was seen. Conclusion The necessary amount of hands-on training is unknown. This study demonstrates that performance increases with prolonged hands-on time but the inter-individual variation among trainees is very large, thereby making it impossible to define the "optimal" time. This supports the use of the concept of mastery learning where each individual trainee can continue training until proficiency is reached.

Head to toe ultrasound: a narrative review of experts’ recommendations of methodological approaches

Critical care ultrasonography (US) is widely used by intensivists managing critically ill patients to accurately and rapidly assess different clinical scenarios, which include pneumothorax, pleural effusion, pulmonary edema, hydronephrosis, hemoperitoneum, and deep vein thrombosis. Basic and advanced critical care ultrasonographic skills are routinely used to supplement physical examination of critically ill patients, to determine the etiology of critical illness and to guide subsequent therapy. European guidelines now recommend the use of US for a number of practical procedures commonly performed in critical care. Full training and competence acquisition are essential before significant therapeutic decisions are made based on the US assessment. However, there are no universally accepted learning pathways and methodological standards for the acquisition of these skills.

Therefore, in this review, we aim to provide a methodological approach of the head to toe ultrasonographic evaluation of critically ill patients considering different districts and clinical applications.

Predictive value of a false-negative focused abdominal sonography for trauma (FAST) result in patients with confirmed traumatic abdominal injury

Objective

To investigate if patients with confirmed traumatic abdominal injury and a false-negative focused abdominal sonography for trauma (FAST) examination have a more favorable prognosis than those with a true-positive FAST.

Methods

This study included 97 consecutive patients with confirmed traumatic abdominal injury (based on computed tomography [CT] and/or surgical findings) who underwent FAST.

Results

FAST was false-negative in 40 patients (41.2%) and true-positive in 57 patients (58.8%). Twenty-two patients (22.7%) had an unfavorable outcome (defined as the need for an interventional radiologic procedure, laparotomy, or death due to abdominal injury). Univariately, a false-negative FAST (odds ratio [OR] 0.24; p = 0.017) and a higher systolic blood pressure (OR, 0.97 per mmHg increase; p = 0.034) were significantly associated with a favorable outcome, whereas contrast extravasation on CT (OR, 7.17; p = 0.001) and shock index classification (OR, 1.89 for each higher class; p = 0.046) were significantly associated with an unfavorable outcome. Multivariately, only contrast extravasation on CT remained significantly associated with an unfavorable outcome (OR, 4.64; p = 0.016). When excluding contrast extravasation on CT from multivariate analysis, only a false-negative FAST result was predictive of a favorable outcome (OR, 0.28; p = 0.038).

Conclusion

Trauma patients with confirmed abdominal injury and a false-negative FAST have a better outcome than those with a positive FAST. FAST may be valuable for risk stratification and prognostication in patients with a high suspicion of abdominal injury when CT has not been performed yet or when CT is not available.

Life threatening bilateral renal trauma in a child

Hematuria in children resulting from trauma should be promptly evaluated. Inappropriate management may result in undesirable consequences. Clinicians should have high index of suspicion for genitourinary injuries in pediatric patients. A case is presented of a boy saved by appropriate management following prompt action resulting from high index of suspicion.

Simulation-based point-of-care ultrasound training: a matter of competency rather than volume

BACKGROUND

Point-of-care ultrasonography plays an increasingly important role in the initial resuscitation of critically ill patients but acquisition of the skill is associated with long learning curves. The skills required to perform ultrasound examinations can be practiced in a simulated setting before being performed on actual patients. The aim of this study was to investigate the learning curves for novices training the FAST protocol on a virtual-reality simulator.

METHODS

Ultrasound novices (N = 25) were instructed to complete a FAST training program on a virtual-reality ultrasound simulator. Participants were instructed to continue training until they reached a previously established mastery learning level, which corresponds to the performance level of a group of ultrasound experts. Performance scores and time used during each FAST examination were used to determine participants' learning curves.

RESULTS

The participants attained the mastery learning level within a median of three (range two to four) attempts corresponding to a median of 1 h 46 min (range 1 h 2 min to 3 h 37 min) of simulation training. The ultrasound novices' examination speed improved significantly with training, and continued to improve even after they attained the mastery learning level (P = 0.011). Twenty-three participants attained the mastery learning level.

CONCLUSION

Novices can attain mastery learning levels using simulation-based ultrasound training with less than, on average, 2 h of practice. However, we found large variations in the amount of training needed, which raises questions about the adequacy of current volume-based models for determining ultrasound competency.

Comparative Analysis of Simulated versus Live Patient-Based FAST (Focused Assessment With Sonography for Trauma) Training

OBJECTIVE

To investigate whether simulated patient (SP)-based training has comparable efficacy as live patient (LP)-based training in teaching Focused Abdominal Sonography for Trauma (FAST) knowledge and skill competencies to surgical residents.

DESIGN

A randomized pretest/intervention/posttest controlled study design was employed to compare the participants' performance in written and practical examinations regarding FAST examination after SP-based versus LP-based training.

SETTING

University-based general residency program at a single institution.

PARTICIPANTS

A total of 29 general surgery residents of various training levels and sonographic experience were recruited by convenience sampling.

RESULTS

There was no correlation between subjects' baseline training level or sonographic experience with either the posttest-pretest score difference or the percentage of subjects getting all 4 windows with adequate quality. There was no significant difference between the improvement in written posttest-pretest scores for SP and LP group, which were 33 ± 9.6 and 31 ± 6.8 (p = 0.40), respectively. With regard to performance-based learning efficacy, a statistically higher proportion of subjects were able to obtain all 4 windows with adequate quality among the LP than the SP group (6/8 vs 1/8, p = 0.01).

CONCLUSION

SP- and LP-based FAST training for surgical residents were associated with similar knowledge-based competency acquisition, but residents receiving LP-based training were better at acquiring adequate FAST windows on live patients. Simulation training appeared to be a valid adjunct to LP practice but cannot replace LP training. Future investigations on how to improve simulation fidelity and its training efficacy for skill-based competencies are warranted.

Prevalence of the "double-line" sign when performing focused assessment with sonography in trauma (FAST) examinations

The double-line sign (DLS) is a wedge-shaped hypoechoic area in Morison's pouch bounded on both sides by echogenic lines. It represents a false-positive finding for free intraperitoneal fluid when performing focused assessment with sonography in trauma examinations. The purpose of this study was to determine the prevalence of DLS. Secondarily, the study will further investigate the relationship between the presence of a DLS and body mass index (BMI). This was a prospective study that enrolled patients over a 7-month period. Inclusion criteria were patients ≥ 18 years of age presenting to the Emergency Department (ED) requiring a FAST examination as part of the patient's standard medical care. Each examination was performed by one of six experienced ultrasonographers. Presence or absence of the DLS was established in real time and gender, height, weight, and BMI were recorded for each patient. The overall prevalence rate of DLS and the corresponding 95 % confidence interval were calculated, as well as the prevalence rates broken down by BMI characterized as underweight, normal weight, overweight, and obese; and age category (18-29, 30-64, and 65+). The Chi-square test and a Fisher's exact test for BMI category were used to compare the prevalence rates of positive DLS among the different demographic groups. 100 patients were enrolled in the study; the overall prevalence was 27 %. There was no statistical significance among the different demographic groups or BMI. The DLS is a prevalent finding. We believe this sign has become more apparent due to improved imaging technology and resolution.

Assessment of the numbers-based model for evaluation of resident competency in emergency ultrasound core applications

Background: The objective of this study was to assess the current numbers-based model of evaluation of emergency medicine residents in emergency ultrasound, specifically by focusing on the proficiency of residents to interpret right upper quadrant, focused abdominal sonogram for trauma, abdominal aorta, first trimester pregnancy, and cardiac scans. Methods: A prospective analysis of emergency medicine residents' competency in emergency ultrasound was conducted in 2009 and 2010. Residents completed a multiple choice style examination primarily assessing residents' diagnostic accuracy. The accuracy and confidence of diagnosis for each resident based on the examinations were compared to his/her training level and number of scans per application completed prior to testing, in order to assess the relationship of experience to competence. Results: Thirty-six emergency medicine residents, postgraduate year 1–3 (n = 15, 8, 13), were enrolled in the study and took the exam. There was a statistically significant relationship between the number of scans and mean exam score for right upper quadrant (p = 0.0013) and abdominal aorta (p = 0.0013) scans. Residents demonstrated a statistically significant improvement in scores at greater than 16 scans for right upper quadrant (p = 0.0018) and 13 scans for abdominal aorta (p = 0.0018). Conclusion: Adequate resident training for interpretation for certain applications such as right upper quadrant and abdominal aorta, may be achievable using smaller numbers than the generally accepted guideline of 25 scans per application. Additionally, the number of scans needed to reach competency may be variable dependent on the specific ultrasound application.

Focused Assessment with Sonography for Trauma in patients with confirmed liver lesions

BACKGROUND AND AIMS

The objective was to determine the sensitivity and specificity of Focused Assessment with Sonography for Trauma (FAST) in patients with confirmed liver lesions and also to compare results from surgeons trained in FAST with results from radiologists trained in general abdominal ultrasound as part of the specialist training. Explorative laparotomy or CT served as gold standard.

MATERIALS AND METHODS

This retrospective study included all patients admitted to our institution from 2003 to 2010 registered with the diagnosis "Injury of the liver or gallbladder". Of 405 patients, 135 patients were eligible for analysis. Seventy-two patients were examined by radiologists and 63 by surgeons.

RESULTS

We found FAST to have a sensitivity, specificity, PPV, and NPV of 79.6%, 100%, 100%, and 68.9%. There was no statistically significant difference between FAST performed by radiologists and surgeons trained in FAST.

CONCLUSION

FAST remains an important screening tool in abdominal trauma including liver lesions, and can be performed at a satisfactory level by surgeons trained in the FAST procedure only.

The learning curve of resident physicians using emergency ultrasonography for cholelithiasis and cholecystitis

BACKGROUND

Emergency department bedside ultrasonography (EUS) can expedite treatment for patients. However, it is unknown how much experience is required for competency in the sonographic diagnosis of cholelithiasis and cholecystitis.

OBJECTIVES

The objective was to assess the learning curve of physicians training in right upper quadrant (RUQ) EUS.

METHODS

This was a prospective study at an urban, academic emergency department from August 1999 to July 2006. Patients with suspected biliary tract disease underwent RUQ EUS followed by abdominal ultra sonography (AUS) by the Department of Radiology. Results of EUS were compared to AUS using a predesigned, standardized data sheet.

RESULTS

A total of 1,837 patients underwent EUS by 127 physicians. The overall sensitivity and specificity of EUS for cholelithiasis were 84% (95% confidence interval [CI] = 81% to 86%) and 86% (95% CI = 83% to 88%), respectively. The overall sensitivity of EUS for ductal dilation, gallbladder wall thickening, pericholecystic fluid, and sludge were each < 60%. When analyzing the EUS test characteristics, for every increase in 10 examinations up to 50 examinations, there was no significant improvement in the sensitivity or specificity for any of these sonographic findings. Moreover, on probit regression analysis, accounting for clustering or correlation among the examinations performed by each of the operators, there was no improvement for detecting any of the sonographic findings except for pericholecystic fluid for every 10 additional examinations performed.

CONCLUSIONS

When adjusting for operator dependence, performing up to 50 EUS examinations appears to have little effect on the accuracy of RUQ EUS. Rather than simply requiring an arbitrary number of examinations, another method of competency assessment may be necessary.

Learning curve of emergency physicians using emergency bedside sonography for symptomatic first-trimester pregnancy

OBJECTIVE

The purpose of this study was to prospectively assess the learning curve of emergency physician training in emergency bedside sonography (EBS) for first-trimester pregnancy complications.

METHODS

This was a prospective study at an urban academic emergency department from August 1999 through July 2006. Patients with first-trimester vaginal bleeding or pain underwent EBS followed by pelvic sonography (PS) by the Department of Radiology. Results of EBS were compared with those of PS using a predesigned standardized data sheet.

RESULTS

A total of 670 patients underwent EBS for first-trimester pregnancy complications by 1 of 25 physicians who would go on to perform at least 25 examinations. The sensitivity and specificity of EBS for an intrauterine pregnancy increased from 80% (95% confidence interval [CI], 71%-87%) and 86% (95% CI, 76%-93%), respectively, for a physician's first 10 examinations to 100% (95% CI, 73%-100%) and 100% (95% CI, 63%-100%) for those performed after 40 examinations. Likewise, the sensitivity and specificity for an adnexal mass or ectopic pregnancy changed from 43% (95% CI, 28%-64%) and 94% (95% CI, 89%-97%) to 75% (95% CI, 22%-99%) and 89% (95% CI, 65%-98%), whereas the sensitivity and specificity for a molar pregnancy changed from 71% (95% CI, 30%-95%) and 98% (95% CI, 94%-99%) to 100% (95% CI, 20%-100%) and 100% (95% CI, 81%-100%). Although detection of an intrauterine or a molar pregnancy improved with training, even with experience including 40 examinations, the sensitivity of EBS for an adnexal mass or ectopic pregnancy was less than 90%.

CONCLUSIONS

There is an appreciable learning curve among physicians learning to perform EBS for first-trimester pregnancy complications that persists past 40 examinations.

An Evidence-Based Approach for Integrating Bedside Ultrasound Into Routine Practice in the Assessment of Undifferentiated Shock

Undifferentiated hypotension remains a central diagnostic and therapeutic challenge in emergency and critical care medicine. Increasingly, bedside ultrasound conducted by intensivists and emergency medicine providers is assuming a central role in diagnosis and resuscitation of hypotension. This review discusses sample algorithms for the bedside ultrasonographic assessment of undifferentiated shock and outlines an evidence-based framework for the intensivist seeking to incorporate bedside ultrasound into daily clinical practice. The literature regarding specific applications including cardiac, thoracic, pulmonary, and vascular assessment is briefly reviewed, as is the evidence pertaining to effective implementation, training, credentialing, and ongoing quality assurance.

Focused assessment with sonography for trauma: the FAST scan

Focused assessment with sonography for trauma or focused abdominal sonography for trauma — the FAST scan, has become a useful modality for the initial evaluation of patients with blunt abdominal trauma. The technique is used to identify free fluid in the abdomen and pelvis and to detect the presence of a pericardial effusion. FAST can be performed by any trained individual, not necessarily a sonographer or radiologist, aiding in the immediate availability of this technique in the emergency situation. We will discuss the applications and sensitivity of this technique in trauma and review the potential pitfalls and limitations which need to be understood if this technique is to be safely applied. The use of FAST for the detection of pneumothoraces in trauma and other advances in FAST scanning, such as scoring systems and paediatric FAST are also reviewed.

Current Role of Emergency US in Patients with Major Trauma

In patients with major trauma, focused abdominal ultrasonography (US) often is the initial imaging examination. US is readily available, requires minimal preparation time, and may be performed with mobile equipment that allows greater flexibility in patient positioning than is possible with other modalities. It also is effective in depicting abnormally large intraperitoneal collections of free fluid, which are indirect evidence of a solid organ injury that requires immediate surgery. However, because US has poor sensitivity for the detection of most solid organ injuries, an initial survey with US often is followed by a more thorough examination with multidetector computed tomography (CT). The initial US examination is generally performed with a FAST (focused assessment with sonography in trauma) protocol. Speed is important because if intraabdominal bleeding is present, the probability of death increases by about 1% for every 3 minutes that elapses before intervention. Typical sites of fluid accumulation in the presence of a solid organ injury are the Morison pouch (liver laceration), the pouch of Douglas (intraperitoneal rupture of the urinary bladder), and the splenorenal fossa (splenic and renal injuries). FAST may be used also to exclude injuries to the heart and pericardium but not those to the bowel, mesentery, and urinary bladder, a purpose for which multidetector CT is better suited. If there is time after the initial FAST survey, the US examination may be extended to extra-abdominal regions to rule out pneumothorax or to guide endotracheal intubation, vascular puncture, or other interventional procedures.

How fast is the focused assessment with sonography for trauma examination learning curve?

OBJECTIVE

Although accuracy for focused assessment with sonography for trauma (FAST) examination interpretation has been widely reported, the learning curve for FAST interpretation by emergency medicine (EM) residents who are novice to ultrasound has not been well described. The present study's objective was to analyse EM resident FAST interpretation accuracy over 18 months.

METHODS

Prospective comparison of EM resident FAST interpretation accuracy for a class of nine EM residents at baseline after initial training, and then every 6 months over 18 months. Accuracy was scored after viewing the same 20 video clip images of the four anatomic views for five FAST examination cases. Three video clips had large anechoic stripe (AS) (>6 mm), four had moderate AS (6 mm > or = AS > or = 3 mm), two had small AS (<3 mm), and eleven had no AS (AS = 0 mm). A surgeon with 20 years of ultrasound experience confirmed the video clip interpretations. Data analysis used descriptive statistics with 95% confidence intervals.

RESULTS

For no AS views, EM resident accuracy was 79.8% (70.3-86.9%) baseline, 91.9% (84.2-96.2%) at 12 months, and 92.9% (85.5-96.9%) at 18 months. For small AS views, resident accuracy was 27.8% (10.7-53.6%) baseline, 66.7% (41.2-85.7%) at 12 months, and 72.2% (46.4-89.3%) at 18 months. For large AS views, resident accuracy was 77.8% (57.3-90.6%) baseline, 86.1% (69.7-94.8%) at 12 months, and 100.0% (84.5-100%) at 18 months.

CONCLUSION

Over 18 months, EM resident FAST interpretation accuracy steadily increased. By 12 months (or 35 examinations), the accuracy of EM residents novice to ultrasound approximated previously reported accuracy rates.

Operator confidence correlates with more accurate abdominal ultrasounds by emergency medicine residents

The purpose of this study was to assess whether greater operator confidence correlates with more accurate focused abdominal ultrasounds (FAUS) by residents. This was a prospective study of novice residents performing FAUS in patients with abdominal pain. FAUS included focused assessment with sonography for trauma, gall bladder, renal, and aortic examinations. Residents answered the question, "How confident are you of your findings?" using a visual scale from 1 (doubtful) to 5 (certain). The results of the resident-performed FAUS were compared to subsequent criterion evaluations. Thirty-eight residents with an average experience of 27 (95% confidence interval [CI] 18-36) prior US examinations evaluated 504 patients. Greater operator confidence correlated with improved accuracy of FAUS (R(2) = 0.858, p = 0.0369). Sensitivity and specificity were 14% (95% CI 4-37 %) and 71% (95% CI 48-88 %) with a confidence level of 2/5 but 85% (95% CI 73-93 %) and 100% (95% CI 97-100 %) with a confidence level of 5/5. Greater operator confidence correlates with improved accuracy in FAUS. This should be considered in the development of training guidelines.

Focused ultrasound training for clinicians

Clinician use of diagnostic ultrasound, particularly at point of care and in emergency situations, is well established. The standard of training courses and of postcourse supervision and accreditation is variable, and international standards are required to maintain safety, accuracy, and credibility of the technique. The accuracy of the technique by trained personnel has been well documented. There is evidence that prereading, a course involving theoretical and practical training, and ongoing mentoring (proctoring) provides high standards of practice. Regular accreditation and continuous comparison with gold standards is required to maintain this level. Most areas of the body are now accessible to clinicians of varied specialties, even those previously thought impossible for ultrasound examination, such as the chest and bone. Training and supervision in rural, remote, and austere environments provides added challenges.

Teaching and Evaluating Ultrasound Skill Attainment: Competency-Based Resident Ultrasound Training for AIUM Accreditation

Modern obstetrics and gynecology practice requires the frequent use of ultrasound and ultrasound training as a required component of obstetrics and gynecology residencies. Although programs do offer training in obstetric ultrasound imaging, education in gynecologic imaging is either absent or limited. This article describes a comprehensive ultrasound curriculum for obstetrics and gynecology residents that has been developed and implemented at the University of New Mexico. The curriculum is competency based and qualifies the graduating resident to seek American Institute of Ultrasound in Medicine laboratory accreditation.

Measurement of endometrial stripe thickness by obstetrics and gynecology residents

OBJECTIVE

How well do obstetrics and gynecology residents measure the endometrial stripe by transvaginal sonography?

STUDY DESIGN

Three obstetrics and gynecology residents at the University of Texas Medical Branch from each year level were tested for their ability to perform endometrial stripe measurements. Measurements of endometrial stripe thickness within 1 mm of the reference value that was obtained by an expert sonographer were deemed to be correct.

RESULTS

Residents correctly measured the endometrial stripe in 14 of 24 cases (58%). Postgraduate year-4 residents correctly measured endometrial stripe thickness in 5 of 6 cases (83%); lower level residents were correct in 9 of 18 cases (50%). The most common error that was noted was an incorrect image plane in 25 of 47 attempts (53%). Fewer errors were committed by upper level as compared with lower level residents (P < .05).

CONCLUSION

By the end of residency, residents can accurately measure the endometrial stripe using transvaginal sonography. Emphasis should be placed on the improvement of the measurement skills.