Prospective analysis of a rapid trauma ultrasound examination performed by emergency physicians

Comparison of gray-scale contrast-enhanced ultrasonography with contrast-enhanced computed tomography in different grading of blunt hepatic and splenic trauma: an animal experiment

To compare the diagnostic value of contrast-enhanced ultrasonography (CEUS) with contrast-enhanced computed tomography (CECT) for the detection of different grading of solid organ injuries in blunt abdominal trauma in animals. A self-made miniature tools were used as models to simulate a blunt hepatic or splenic trauma in 16 and 14 anesthetized dogs, respectively. Baseline ultrasound, CEUS and CECT were used to detect traumatic injuries of livers and spleens. The degree of injuries was determined by CEUS according to the American Association for the Surgery of Trauma (AAST) scale and the results compared with injury scale based on CECT evaluation. CEUS showed 22 hepatic injury sites in 16 animals and 17 splenic injury sites in other 14 animals. According to AAST scale, 2 grade I, 4 grade II, 3 grade III, 5 grade IV and 2 grade V hepatic lesions were present in 16 animals; 2 grade I, 4 grade II, 6 grade III and 2 grade IV splenic lesions in 14 animals. On CECT scan, 21 hepatic and 17 splenic injuries were demonstrated. According to Becker CT scaling for hepatic injury, 1 grade I, 2 grade II, 4 grade III, 5 grade IV and 2 grade V hepatic injuries were present. On the basis of Buntain spleen scaling, 2 grade I, 5 grade II, 5 grade III, 2 grade IV splenic injuries were showed. After Spearman rank correlation analysis, the agreement of CEUS with CECT on the degree of hepatic and splenic injury is 93.3% and 92.9%, respectively. CT is currently considered as the reference method for grading blunt abdominal trauma, according to experiment results, CEUS grading showed high levels of concordance with CECT. CEUS can accurately determine the degree of injury and will play an important role in clinical application.

Use of ultrasound by emergency medical services: a review

Prehospital ultrasound has been deployed in certain areas of the USA and Europe. Physicians, emergency medical technicians, and flight nurses have utilized a variety of medical and trauma ultrasound assessments to impact patient care in the field. The goal of this review is to summarize the literature on emergency medical services (EMS) use of ultrasound to more clearly define the potential utility of this technology for prehospital providers.

Impact of surgeon-performed ultrasound on diagnosis of abdominal pain

Background:

A randomised study was performed to evaluate the diagnostic accuracy of surgeon-performed ultrasound in the emergency department for patients presenting with abdominal pain.

Methods:

Surgeons responsible for the examination of study patients underwent 4 weeks of ultrasound training. 800 patients who were attending the emergency department for abdominal pain were randomised to undergo or not undergo surgeon-performed ultrasound as a complement to standard examination. The preliminary diagnosis made by the surgeon, with or without ultrasound, was compared with the final diagnosis made by a senior surgeon 6–8 weeks later.

Results:

Diagnostic accuracy was significantly higher in the group examined with ultrasound (64.7% vs 56.8%, p = 0.027). Ultrasound proved to be helpful in making or confirming a correct diagnosis in 24.1% of cases receiving ultrasound and to contribute in 2.9%. In 22.3% of patients the diagnosis of non-specific pain was confirmed by normal findings. Ultrasound was misleading in 10.2% of cases and had no influence on the diagnosis in 40.0%.

Conclusion:

For patients with acute abdominal pain, higher diagnostic accuracy is achieved when surgeons use ultrasound as a diagnostic complement to standard examination. The use of bedside ultrasound should be considered in emergency departments.

Bedside ultrasound in pediatric emergency medicine

Bedside emergency ultrasound has been used by emergency physicians for >20 years for a variety of conditions. In adult centers, emergency ultrasound is routinely used in the management of victims of blunt abdominal trauma, in patients with abdominal aortic aneurysm and biliary disease, and in women with first-trimester pregnancy complications. Although its use has grown dramatically in the last decade in adult emergency departments, only recently has this tool been embraced by pediatric emergency physicians. As the modality advances and becomes more available, it will be important for primary care pediatricians to understand its uses and limitations and to ensure that pediatric emergency physicians have access to the proper training, equipment, and experience. This article is meant to review the current literature relating to emergency ultrasound in pediatric emergency medicine, as well as to describe potential pediatric applications.

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.

Ultrasound to detect haemothorax after chest injury

A short cut review was carried out to establish whether ultrasonography is as sensitive and specific as chest x ray or computed tomography (CT) scan in detecting haemothorax after chest trauma. Thirty-nine papers were found using the reported searches, of which six presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are shown in table 3. It is concluded that ultrasonography is more sensitive and as specific as chest x ray at detecting haemothorax in patients with chest trauma.

Automated detection of a blood pool in ultrasound images of abdominal trauma

Ultrasound imaging is commonly used for emergency diagnosis of blunt trauma. Portable scanners are able to provide adequate imaging in remote and dangerous areas; however, medical expertise may not be available in the immediate local area to interpret the acquired images. The presence of pooled blood in the abdomen is a critical clinical symptom after trauma. This article describes an automated algorithm to detect blood pools in ultrasound images of abdominal trauma. The algorithm creates and uses a feature space consisting of local intensities, averaged local gradient magnitudes and second-order central rotation invariant moments. Successful tests were performed with a set of clinical images of a liver-kidney interface covering the Morrison's pouch, which is the most likely space for blood from an abdominal injury to gather. When implemented in a portable scanner, the reported algorithm will provide rapid, on-the-spot detection of trauma-induced blood pooling and advance notice of a significant blunt traumatic injury.

Assessment of knowledge retention and the value of proctored ultrasound exams after the introduction of an emergency ultrasound curriculum

BACKGROUND

Optimal training required for proficiency in bedside ultrasound is unknown. In addition, the value of proctored training is often assumed but has never been quantified.

METHODS

To compare different training regimens for both attending physicians and first year residents (interns), a prospective study was undertaken to assess knowledge retention six months after an introductory ultrasound course. Eighteen emergency physicians and twelve emergency medicine interns were assessed before and 6 months after an introductory ultrasound course using a standardized, image-based ultrasound test. In addition, the twelve emergency medicine interns were randomized to a group which received additional proctored ultrasound hands-on instruction from qualified faculty or to a control group with no hands-on instruction to determine if proctored exam training impacts ultrasound knowledge. Paired and unpaired estimates of the median shift in test scores between groups were made with the Hodges-Lehmann extension of the Wilcoxon-Mann-Whitney test.

RESULTS

Six months after the introductory course, test scores (out of a 24 point test) were a median of 2.0 (95% CI 1.0 to 3.0) points higher for residents in the control group, 5.0 (95% CI 3.0 to 6.0) points higher for residents in the proctored group, and 2.5 (95% CI 1.0 to 4.0) points higher for the faculty group. Residents randomized to undergo proctored ultrasound examinations exhibited a higher score improvement than their cohorts who were not with a median difference of 3.0 (95% CI 1.0 to 5.0) points.

CONCLUSION

We conclude that significant improvement in knowledge persists six months after a standard introductory ultrasound course, and incorporating proctored ultrasound training into an emergency ultrasound curriculum may yield even higher knowledge retention.

Performance of abdominal ultrasonography in pediatric blunt trauma patients: a meta-analysis

OBJECTIVE

The objective of the study was to obtain the best estimates of the test performance of abdominal ultrasonography (US) for identifying children with intraabdominal injuries (IAIs).

METHODS

We gathered studies on the use of abdominal US in injured children from the following sources: a MEDLINE and Embase search, hand searches of 5 specialty journals and 4 clinical textbooks, the bibliographies of all identified articles, and contact with experts. Both prospective and retrospective studies were included if they used abdominal US for the detection of intraperitoneal fluid or IAIs in blunt trauma patients less than 18 years of age. All authors independently abstracted data from the selected studies. Disagreements between abstractors were resolved by mutual agreement.

RESULTS

Twenty-five articles met the inclusion criteria, and 3838 children evaluated with abdominal US were included. Abdominal US had the following test characteristics for identifying children with hemoperitoneum: sensitivity, 80% (95% confidence interval [CI] 76%-84%); specificity, 96% (95% CI 95%-97%); positive likelihood ratio, 22.9 (95% CI 17.2-30.5); and negative likelihood ratio, 0.2 (95% CI 0.16-0.25). Using the most methodologically rigorous studies, however, yielded the following test characteristics of abdominal US for identifying children with hemoperitoneum: sensitivity, 66% (95% CI 56%-75%); specificity, 95% (95% CI 93%-97%); positive likelihood ratio, 14.5 (95% CI 9.5-22.1); and negative likelihood ratio, 0.36 (95% CI 0.27-0.47).

CONCLUSIONS

Abdominal US has a modest sensitivity for the detection of children with hemoperitoneum; however, its test performance characteristics worsen when only the most methodologically rigorous articles are included. A negative US examination has questionable utility as the sole diagnostic test to rule out the presence of IAI. Because of the high risk of IAI, a hemodynamically stable child with a positive US examination should immediately undergo abdominal computed tomographic scanning.

Clinician-performed focused sonography for the resuscitation of trauma

Traumatic death remains pandemic. The majority of preventable deaths occur early and are due to injuries or physiologic derangements in the airway, thoracoabdominal cavities, or brain. Ultrasound is a noninvasive and portable imaging modality that spans a spectrum between the physical examination and diagnostic imaging. It allows trained examiners to immediately confirm important syndromes and answer clinical questions. Newer technologies greatly increase the fidelity, accessibility, ease of use, and informatic manipulation of the results. The early bedside use of focused ultrasound as the initial imaging modality used to detect hemoperitoneum and hemopericardium in the resuscitation of the injured patient has become an accepted standard of care. Widespread dissemination of basic ultrasound skills and technology to facilitate this brings ultrasound to many resuscitative and critical care areas. Although not as widely appreciated, the focused use of ultrasound may also have a role in detecting hemothoraces and pneumothoraces, guiding airway management, and detecting increased intracranial pressure. Intensivists generally utilize a treating philosophy that requires the real-time integration of many divergent sources of information regarding their patients' anatomy and physiology. They are therefore positioned to take advantage of focused resuscitative ultrasound, which offers immediate diagnostic information in the early care of the critically injured.

Ultrasound applications in mass casualties and extreme environments

A mass-casualty incident is one in which the number of patients with injuries exceeds the available medical resources to care for them in a timely manner. In such a situation, the numerous advantages of ultrasonography make it an ideal triage tool for helping clinicians rapidly screen patients. Experiences during the 1988 Armenian earthquake and the 1999 Turkish earthquake demonstrated the proficiency of ultrasound in providing rapid clinical data to the physicians caring for the mass-casualty patients. Wireless and satellite transmission of ultrasound images also has been shown to be feasible and may be applied to mass-casualty situations. In addition, ultrasound applications have been demonstrated to aid in the diagnosis of various conditions, including pneumothorax, in the International Space Station. Ultrasound's portability, reproducibility, accuracy, and ease of use will make it an important diagnostic instrument for future space missions.

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.

History of emergency and critical care ultrasound: The evolution of a new imaging paradigm

The tradition of clinical ultrasound in the hands of physicians who provide critical care to the most acutely ill patients stretches back into the 1980s and is rich with experiences from surgical, emergency medicine, and other practices. Now, as critical care ultrasound explodes around the world, it is important to realize the path its development has taken and learn from trials and tribulations of early practitioners in the field. The development and battles for the right to use ultrasound at the patient's bedside for >20 yrs is described in relation to its emergency medicine and surgical origins. Approaches to education, scanning, documentation, and organization at the national and regional levels are described.

Contrast-Enhanced Ultrasound for Blunt Abdominal Trauma

Sonography is widely used in the initial diagnostic assessment of blunt abdominal trauma in adults and children. It has been formally incorporated worldwide into the routine armamentarium available for emergency diagnosis and treatment as a means of rapid detection of free abdominal fluid, normally referred to as FAST (Focused Assessment with Sonography in Trauma). However, there is some controversy regarding its value because free abdominal fluid may be lacking in patients with abdominal organ injuries from blunt trauma. More recently, a new ultrasound technique has been developed using contrast agents. Contrast-enhanced ultrasound performs better than the non-contrast-enhanced technique for the detection of abdominal solid organ injuries and can play an important role in the prompt evaluation of patients with blunt trauma. Furthermore, contrast-enhanced ultrasound can be used in the follow-up of patients who have solid organ lesions and are managed with nonoperative treatment, avoiding radiation and iodinated contrast medium exposure.

A bedside ultrasound curriculum for medical students: prospective evaluation of skill acquisition

OBJECTIVE

We conducted a study to evaluate the efficacy of an introductory ultrasound (US) curriculum for medical students rotating through our emergency department.

MATERIALS AND METHODS

Third- and 4th-year medical students indicated their previous US experience and were given a pretest consisting of static US images to assess baseline interpretation skills. They participated in a 45-min interactive didactic session followed by a 45-min session of hands-on experience practicing real-time US image acquisition on a normal model. After this session, we tested the timing and quality of their image acquisition skills on a separate normal model. Quality of images was based on a point value from 0 to 2 per image. This was followed by a posttest of static US images, which was graded in the same manner as the pretest.

RESULTS

Thirty-one students participated in the study. Median time to acquire 2 images was 112.5 sec (range = 15420 sec). Acquisition time was unaffected by previous experience (p = .97). The mean score on the quality of 2 images (maximum score = 4) was 3.84; median was 4 (range = 14). Image quality was significantly better in participants with previous US experience (p = .014). Scores on interpretation of static images improved significantly from pretest to posttest by a median of 8.25 points (p = .0001).

CONCLUSION

Our introductory US course is effective at significantly improving medical students' interpretation of static US images. The majority of students were able to acquire high quality images in a short period of time after this session.

Accuracy of Trauma Ultrasound in Major Pelvic Injury

BACKGROUND

Trauma ultrasound (US) utilizing the focused assessment with sonography in trauma (FAST) is often performed to detect traumatic free peritoneal fluid (FPF). Yet its accuracy is unclear in certain trauma subgroups such as those with major pelvic fractures whose emergent diagnostic and therapeutic needs are unique. We hypothesized that in patients with major pelvic injury (MPI) trauma ultrasound would perform with lower accuracy than has previously been reported.

METHODS

Retrospective analysis of adult trauma patients with pelvic fractures seen at an urban Level I emergency department and trauma center. Patients were identified from the institutional trauma registry and ultrasound database from 1999 to 2003. All patients aged >16 years with MPI (Tile classification A2, all type B and C pelvic fractures, and type C acetabular fractures determined by a blinded orthopedic traumatologist) and who had a trauma US performed during the initial emergency department evaluation were included. All ultrasounds were performed by emergency physicians or surgeons using the four-quadrant FAST evaluation. Results of US were compared with one of three reference standards: abdominal/pelvic computed tomography, diagnostic peritoneal tap, or exploratory laparotomy. Two-by-two tables were constructed for diagnostic indices.

RESULTS

In all, 96 patients were eligible; 9 were excluded for indeterminate ultrasound results. Of the remaining 87 patients, the pelvic fracture types were distributed as follows: 9% type A2, 72% type B, 16% type C, and 3% type C acetabular fractures. Overall US sensitivity for detection of FPF was 80.8%, specificity was 86.9%, positive predictive value was 72.4%, and negative predictive value was 91.4%. Categorization of sensitivity according to pelvic ring fracture type is as follows: type A2 fractures: sensitivity and specificity, 75.0%; type B fractures: sensitivity, 73.3%, specificity, 85.1%; and type C fractures (pelvis and acetabulum): sensitivity and specificity, 100%. Of the true-positive US results, blood was the FPF in 16 of 21 (76%) and urine from intraperitoneal bladder rupture in 4 in 21 (19%) patients.

CONCLUSION

US in the initial evaluation of traumatic peritoneal fluid in major pelvic injury patients has lower sensitivity and specificity than previously reported for blunt trauma patients. Additionally, uroperitoneum comprises a substantial proportion of traumatic free peritoneal fluid in patients with MPI.

Evaluation of focussed assessment with sonography in trauma (FAST) by UK emergency physicians

OBJECTIVES

To evaluate the introduction of a focussed assessment with sonography in trauma (FAST) scan into the early assessment of trauma patients in the UK.

METHODS

The setting was an inner city teaching hospital emergency department (annual attendance 100,000). All patients aged 16 or over admitted to the resuscitation room after blunt trauma were included in a prospective observational study. Patients had a FAST scan performed at the end of the primary survey. Results were compared to results of other investigations, laparotomy, postmortem examination, or observation.

RESULTS

153 patients were entered into the study. The sensitivity of the FAST scan was 78% and specificity was 99%.

CONCLUSION

FAST is a highly specific "rule in" technique and is useful in the initial assessment of trauma patients. Emergency physicians can perform FAST after a brief training period.

Chest Ultrasonography in Lung Contusion

STUDY OBJECTIVE

Despite the high prevalence of chest trauma and its high morbidity, lung contusion (LC) often remains undiagnosed in the emergency department (ED). The present study investigates the possible clinical applicability of chest ultrasonography for the diagnosis of LC in the ED in comparison to radiography and CT.

MATERIALS AND METHODS

One hundred twenty-one patients admitted to the ED for blunt chest trauma were investigated using ultrasonography by stage III longitudinal scanning of the anterolateral chest wall to detect LC. Data were retrospectively collected in an initial series of 109 patients (group 1) and prospectively in the next 12 patients (group 2). All patients who presented with pneumothorax were excluded. After the ultrasound study, all patients were submitted to chest radiography (CXR) and CT. The sonographic patterns indicative of LC included the following: (1) the alveolointerstitial syndrome (AIS) [defined by increase in B-line artifacts]; and (2) peripheral parenchymal lesion (PPL) [defined by the presence of C-lines: hypoechoic subpleural focal images with or without pleural line gap].

RESULTS

The diagnosis of LC was established by CT scan in 37 patients. If AIS is considered, the sensitivity of ultrasound study was 94.6%, specificity was 96.1%, positive and negative predictive values were 94.6% and 96.1%, respectively, and accuracy was 95.4%. If PPL is alternatively considered, sensitivity and negative predictive values drop to 18.9% and 63.0%, respectively, but both specificity and positive predictive values increased to 100%, with an accuracy of 65.9%. Radiography had sensitivity of 27% and specificity of 100%.

CONCLUSIONS

Chest ultrasonography can accurately detect LC in blunt trauma victims, in comparison to CT scan.

Selective nonoperative management of blunt abdominal trauma

The management of patients with blunt abdominal trauma has evolved over the past two decades with increasing reliance on a non-operative approach. An in-depth understanding of the clinical and radiographic parameters used to determine those who may be eligible for this form of treatment is an essential component of modern trauma care. This case-based review highlights critical aspects of non-operative management and provides a framework for the role of the emergency medicine provider.

Trauma during pregnancy

Trauma is the leading nonobstetrical cause of maternal death. The effect of trauma on the pregnant woman and unborn fetus can be devastating. The major causes of maternal injury are blunt trauma, penetrating trauma, burns, falls, and assaults. There are specific changes associated with pregnancy that are important for the clinician to consider when providing care to these patients. Initial management of traumatic injuries during pregnancy is essential for maternal and fetal well-being. This review outlines common causes of maternal trauma, the initial assessment of the pregnant trauma patient, and ongoing care for the pregnant trauma patient and unborn fetus.

Ultrasonography in community emergency departments in the United States: access to ultrasonography performed by consultants and status of emergency physician-performed ultrasonography

STUDY OBJECTIVE

Nearly all emergency medicine residency programs provide some training in emergency physician-performed ultrasonography, but the extent of emergency physician-performed ultrasonography in community emergency departments (EDs) is not known. We seek to determine the state of ultrasonography in community EDs in terms of access to ultrasonography by other specialists and performance of ultrasonography by emergency physicians.

METHODS

A 6-page survey that addressed access to ultrasonography performed by other specialists and emergency physician-performed ultrasonography was designed and pilot tested. A list of all US ED directors was obtained from the American College of Emergency Physicians. Twelve hundred of 5264 EDs were randomly selected to receive the anonymous survey, with responses tracked by separate postcard. There were 3 mailings from Fall 2003 to Spring 2004.

RESULTS

Overall response rate was 61% (684/1130). Respondents who self-reported as being academic with emergency medicine residents were excluded from further analysis (n=35). A sensitivity analysis (reported in parentheses) was performed on the key outcome question to adjust for response bias. As reported by ED directors, ultrasonography was available in the ED for use by emergency physicians at all times in 19% of EDs (12% to 28%), with an additional 15% (9% to 21%) reporting a machine available for use by emergency physicians in some capacity and 66% (51% to 80%) reporting that there was no access to a machine for emergency physician use. ED directors reported being requested or required to limit ultrasonography orders performed by radiology in 41% of EDs, with less timely access to radiology-performed ultrasonography in off hours. Of EDs with emergency physician-performed ultrasonography, the most common applications were Focused Assessment with Sonography for Trauma (FAST) examination (85%), code situation (72%), and check for pericardial effusion (67%). Of physicians performing ultrasonography, 16% stated they were currently requesting reimbursement (billing). The primary reason cited for not implementing emergency physician-performed ultrasonography was lack of emergency physician training. For the statement "emergency medicine residents now starting residency should be trained to perform and interpret focused bedside ultrasonography," 84% of ED directors agreed, 14% were neutral, and less than 2% disagreed.

CONCLUSION

Community ED directors continue to report barriers to obtaining ultrasonography from consultants, especially in off hours. Nineteen percent of community ED directors report having a machine available for emergency physician use at all times; however, two thirds of EDs report no access to ultrasonography for emergency physician use. A majority of community ED directors support residency training in emergency physician-performed ultrasonography.

ED ultrasound in hepatobiliary disease

To evaluate the diagnostic accuracy of gallbladder ultrasound performed by emergency physicians (EPUS) in patients with right upper quadrant (RUQ) and epigastric (EPI) pain, adults>18 years of age with RUQ or EPI pain were prospectively evaluated by physical examination, laboratory data, and EPUS followed by a blinded radiology department ultrasound (RADUS). Diagnostic categories included: "normal gallbladder"; "uncomplicated symptomatic cholelithiasis" (uncomplicated SCL; stones present but symptoms and signs relieved and no abnormal blood-work); or "complicated symptomatic cholelithiasis" (CSCL; stones and positive symptoms and signs including abnormal blood-work). Final Emergency Department patient assessments based on the RADUS were compared to the EPUS. Over 2-years, 127 patients were enrolled. The sensitivity of the EPUS for detecting stones was 94% (positive predictive value 99%; specificity 96%; negative predictive value 73%). In conclusion, the EPUS is a highly sensitive and reliable indicator of the presence of gallstones.

Survey of attitudes of senior emergency physicians towards the introduction of emergency department ultrasound

INTRODUCTION

Emergency department ultrasound (EDU) is widely practised in the USA, Australia, parts of Europe, and Asia. EDU has been used in the UK since the late 1990s but as yet, few areas have established a practice.

OBJECTIVES

To assess the current climate of opinion with respect to the practice, constraints, and establishment of EDU among emergency department (ED) consultants on the island of Ireland.

METHODS

A postal questionnaire was formulated, piloted, and assessed for ambiguity by a sample of ED consultants and an independent non-ED consultant, prior to being mailed to all ED consultants in Ireland.

RESULTS

Of the 58 consultants canvassed 46 (79%) responded. Of the respondents, 40 (87%) strongly agreed/agreed that EDU is appropriate and should be performed in the ED. Of these, 3 (7%) are currently performing EDU; 37 (80%) have not had formal training in EDU, however 42 (91%) support the establishment of national guidelines for training in focused ultrasound in the ED. Problems instituting EDU were often multifactorial. Commonly highlighted difficulties included financial issues (24 respondents, 52%) and radiology department support (16 respondents, 34%). Other cited problems include varying interdepartmental practices (15 respondents, 33%) and (for some EDs) low numbers of patients requiring EDU, with projected difficulties in skills maintenance.

CONCLUSION

Despite the vast majority of ED consultants being in favour of EDU, very few actually perform it on a regular basis or have had any formal training. Highlighted difficulties in EDU implementation included financial constraints, lack of support from radiology departments, and lack of formal training.

Ultrasonography for Interval Assessment in the Nonoperative Management of Hepatic Trauma

Abdominal ultrasonography (US) is gaining widespread acceptance as a valuable diagnostic tool in the initial evaluation of trauma victims. We investigated the utility of US as a follow-up radiologic study in nonoperative hepatic trauma. Patients with liver injury designated for non-operative management were prospectively studied over a 2-year period at our primary adult resource center for trauma. Computed tomography (CT) and radiologist-performed US were obtained at admission and at 1 week. The ability of US to detect lesions, fluid, and complications was evaluated by comparing with the corresponding CT. Twenty-five hepatic trauma patients in the study were successfully managed nonoperatively and had both initial and follow-up US and CT scans: 1 (4%) grade I, 5 (20%) grade II, 7 (28%) grade III, 7 (28%) grade IV, and 5 (20%) grade V. Four complications developed [biloma (3) and biliary fistula (1)] in 3 patients with grade IV injury and 1 with a grade II injury. Interval US appropriately detected a complication or confirmed the absence of complication in all (13/13, 100%) patients with low-grade (I–III) injury and only missed a small biloma in one patient with a grade IV injury. Interval US and CT agreement was 92 per cent for change in hemoperitoneum or parenchymal lesion. Ultrasonography is a convenient imaging modality in the evaluation of hepatic trauma. US is sufficient to detect or exclude complications in low-grade injuries. In high-grade injuries, US may be an adjunct to CT for definitive interval assessment.

Blunt trauma to the spleen: ultrasonographic findings

The spleen is the most frequently injured organ in adults who sustain blunt abdominal trauma. Splenic trauma accounts for approximately 25% to 30% of all intra-abdominal injuries. The management of splenic injury has undergone rapid change over the last decade, with increasing emphasis on splenic salvage and non-operative management. Identifying the presence and degree of splenic injury is critical in triaging the management of patients. Imaging is integral in the identification of splenic injuries, both at the time of injury and during follow-up. Although CT remains the gold standard in blunt abdominal trauma, US continues to play an important role in assessing the traumatized spleen. This pictorial review illustrates the various ultrasonographic appearances of the traumatized spleen. Correlation with other imaging is presented and complications that occur during follow-up are described.

Is definitive abdominal evaluation required in blunt trauma victims undergoing urgent extra-abdominal surgery?

OBJECTIVES

To evaluate the utility of routine abdominal computed tomographic (CT) scanning for abdominal evaluation of blunt trauma patients before urgent extra-abdominal surgery.

METHODS

In this observational cohort study, we prospectively enrolled all blunt trauma patients at least 8 years of age presenting to the emergency department of a Level 1 trauma center who were initially considered to require urgent extra-abdominal surgery within 24 hours of presentation. Patients were excluded if they had any of the following: 1) isolated extremity trauma, 2) signs or symptoms of intra-abdominal injury (including systolic blood pressure < 90 mm Hg; abdominal, flank, or costal margin tenderness; abdominal wall contusion or abrasion; pelvic fracture; and gross hematuria), or 3) unreliable findings on abdominal examination (Glasgow Coma Scale score < 14, paralysis, or mental retardation). Clinical data were documented on a data sheet before abdominal CT scanning.

RESULTS

A total of 254 patients, with a mean (+/-SD) age of 32.3 (+/-16.1) years, were enrolled. A total of 201 patients ultimately underwent urgent extra-abdominal surgery for the following procedures: orthopedic, 182 (91%); facial, 17 (8%); laceration, 7 (3%); vascular, 6 (2%); neurosurgical, 3 (1%); urology, 2 (1%); and ophthalmology, 1 (0.4%). Three patients (1.2%; 95% confidence interval = 0.2% to 3.4%) were found to have intra-abdominal injuries. Two patients had splenic injuries that required only observation. One patient (0.4%; 95% confidence interval = 0% to 2.2%) underwent laparotomy. This patient sustained multiple injuries in a motorcycle crash, including splenic, kidney, and pancreatic injuries, and underwent a splenectomy.

CONCLUSIONS

Abdominal CT scanning has a low yield in trauma patients whose sole indication for diagnostic abdominal evaluation is the need for general anesthesia for urgent extra-abdominal surgery. A small percentage of these patients, however, will have important intra-abdominal injuries such that further refinement of the recommendations for diagnostic study in this select population is needed.

The fast is positive, now what? Derivation of a clinical decision rule to determine the need for therapeutic laparotomy in adults with blunt torso trauma and a positive trauma ultrasound

INTRODUCTION

The object of this study was to derive a clinical decision rule for therapeutic laparotomy among adult blunt trauma patients with a positive abdominal ultrasound for trauma (FAST) examination.

METHODS

We retrospectively reviewed the trauma registry and medical records of all critical trauma patients who underwent a FAST examination in the emergency department (ED) in a university Level I trauma center over a 3-year period. Blunt trauma patients aged >16 years who had a positive FAST examination (defined as the presence of intraperitoneal fluid) were eligible. We selected seven clinical and ultrasound variables available during ED resuscitation for analysis: age, presence of an episode of hypotension (systolic blood pressure <90 torr in the ED), presence of abdominal tenderness, chest injury, pelvic fracture, femur fracture, and FAST fluid location (right upper quadrant [RUQ] only; RUQ plus other location; other location only). The primary outcome variable was whether a laparotomy was performed and whether this laparotomy was needed to provide the definitive surgical intervention ("therapeutic laparotomy"). We analyzed the variables using binary recursive partitioning analysis to create a decision rule.

RESULTS

There were 2336 FAST examinations performed during the study period, resulting in 230 (9.8%) positive examinations in patients meeting inclusion criteria. There were 135 patients who had therapeutic laparotomies and 95 who did not need laparotomy. The groups were similar in baseline characteristics. In the recursive partitioning analysis, the first node in the decision tree was the presence of fluid in the RUQ. Of the 144 patients with RUQ fluid, 105 (73%, 95% confidence interval [CI] 64%-80%) required therapeutic laparotomy. Of the 86 patients without RUQ fluid, 30 (35%, 95% CI 25%-46%) nevertheless required therapeutic laparotomies, and the variables blood pressure, femur fracture, abdominal tenderness, and age further divided these patient into high- and low-risk groups. Of the 12 patients without RUQ fluid who had normal blood pressures, no femur fractures, no abdominal tenderness, and were aged 60 years and younger, none (95% CI 0%-22%) required therapeutic laparotomy. In conclusion, given a positive FAST examination, the presence of fluid in the RUQ is an important predictor of the need for therapeutic laparotomy.

CONCLUSION

In the absence of fluid in the RUQ, there are other clinical variables that may allow for the development of a clinical decision rule regarding the need for therapeutic laparotomy.

Prospective analysis of the effect of physician experience with the FAST examination in reducing the use of CT scans

OBJECTIVE

The objective of this study was to examine the effect of ultrasound experience level on emergency physicians' Focused Assessment with Sonography for Trauma (FAST) exam accuracy and emergency physicians' confidence in using FAST findings to assist in managing patients with blunt trauma.

METHODS

This prospective, consecutive enrolment study evaluated adult trauma team activation blunt trauma patients. Based on the number of post-training FAST exams carried out, 11 attending emergency physicians were grouped into A (<25 exams, n = 4), B (26-50 exams, n = 4) or C (>50 exams, n = 3). The FAST exam was carried out prior to other diagnostic studies. The emergency physicians were asked to prospectively judge their perception of the need for surgery, abdominal CT or no further tests. All study patients ultimately underwent CT, diagnostic peritoneal lavage or laparotomy. Among each physician group, the number of subsequent CT scans deemed necessary by the emergency physician after a 'normal' FAST was calculated and compared.

RESULTS

Accuracy was greatest in group C. Sixty-nine of 80 patients in group A had a normal FAST exam; emergency physicians deemed CT necessary in 68/69 cases (99%; confidence interval [CI] 92-100%). Eighty-two of 98 patients in group C had a normal FAST exam; emergency physicians deemed CT necessary in 19/82 cases (23%; CI 15-34%). Physicians in groups B and C were less likely to order CT after a normal FAST than group A (P < 0.001).

CONCLUSIONS

FAST accuracy was greatest among more experienced emergency physicians. A normal FAST exam assisted more experienced emergency physicians with the perceived need to order significantly fewer CT scans than less experienced emergency physicians.

FAST on operational military deployment

BACKGROUND AND OBJECTIVE

Handheld ultrasound, because of its light weight, size, rugged design, and relative simplicity of use is ideal for use on operational military deployment. These machines have been used in the diagnosis of a range of traumatic conditions including abdominal, thoracic, and extremity trauma in the hospital environment, yet few data exist on their use during military operations. This paper presents experience of handheld focused assessment with sonography for trauma (FAST) on operational military deployment.

METHOD

Over a two month period, handheld FAST was performed by a single surgeon during the circulation phase of the primary survey in trauma patients presenting to the British Military Hospital in Iraq.

RESULTS

Fifteen from casualties underwent a FAST examination. Ten were victims of blunt trauma, two had received injuries anti-personnel mines, and three had penetrating injuries from ballistic trauma. There was one positive FAST, confirmed at laparotomy as bleeding from a liver injury. Thirteen scans were negative and remained negative on repeat FAST at 6 hours. One further patient with a negative FAST underwent laparotomy because of transectory, there was no intra-abdominal blood or fluid at surgery.

CONCLUSION

Handheld FAST is a valuable technique for investigating abdominal or thoracic bleeding in single or multiple casualty events on operational military deployment.

Change in differential diagnosis and patient management with the use of portable ultrasound in a remote setting

OBJECTIVE

Physicians practicing in remote areas are typically limited in their choice of diagnostic tools. The goal of this study was to determine whether the use of a portable ultrasound (US) device on selected patients in a remote setting would alter physician diagnosis and management.

METHODS

This was a prospective observational study of the affects of US on physician decision making deep in the Amazon jungle. A battery-operated Sonosite 180 Plus with 2 interchangeable transducers (4-7-MHz broadband intercavitary transducer and 2-5-MHz broadband abdominal transducer) was used. The patient population consisted of local tribal people. Two of the physicians on the team performed all US examinations. Team physicians requesting US examinations filled out a survey before and after the US examination. Before the US, the referring physician filled out a survey describing the patient's initial complaint, pertinent past medical history and physical findings, and an initial (pre-US) differential diagnosis and planned treatment with expected disposition. After the results of the US were reviewed with the referring physicians, the doctors were asked to fill out the remainder of the survey, allowing comparison of pre- and post-US differential diagnosis, treatment plan, and disposition.

RESULTS

A total of 25 US studies were performed during this study (1 trauma US scan, 6 hepatobiliary studies, 5 transabdominal pelvic scans, 7 transvaginal pelvic studies, 3 renal studies, and 3 abdominal aortic scans). The monitor on the US unit experienced a rare failure shortly after being used at 17,000 ft and then 10 times at sea level, and no further US scans could be performed. US scan results dramatically altered the disposition of 7 patients, including 4 patients who avoided a potentially dangerous 2-day evacuation to more definitive medical care. Three patients were found to need rapid referral to the nearest clinic for surgical evaluation.

CONCLUSIONS

When used in a remote location, portable US provides a significant benefit that can dramatically alter disposition and treatment.

Ultrasound-assisted paracentesis performed by emergency physicians vs the traditional technique: a prospective, randomized study

STUDY OBJECTIVE

To determine if emergency center ultrasound (ECUS) can be of value to emergency physicians in the evaluation of possible ascites and accompanying decisions to perform emergent paracentesis.

METHODS

During a 7-month period, patients suspected of having ascites and potentially requiring paracentesis were prospectively entered into a randomized study in an urban public hospital emergency center (>140 000 annual visits). Patients were randomized to receive paracentesis using the traditional or the bedside ECUS-assisted technique. Indications for paracentesis included known liver disease and obvious ascites as well as suspected ascites or suspected subacute bacterial peritonitis. Participating physicians had received a minimum of 1 hour of formal didactic ultrasound training that included gallbladder, renal, vascular, and bladder studies as well as the focused abdominal sonography for trauma examination for trauma and the detection of ascites. A portable Terason 2000 laptop ultrasound machine with a 5-MHz probe was used to scan the patients. Data collected included the patients' characteristics, estimation of ascitic fluid volume, number of attempts made to obtain fluid, speed of paracentesis, and the operator's overall evaluation of the ECUS-assisted technique, if used.

RESULTS

Of 100 enrolled patients, 56 received the ECUS-assisted technique. Of 42 patients with ascites, 40 (95%) were successfully aspirated and 14 (25%) did not receive paracentesis because no ascites or insignificant amount of ascites was visualized. One patient was noted to have a large cystic mass in the left lower quadrant and another patient had a ventral hernia. Of the 44 patients randomized to the traditional technique, 27 (61%) were successfully aspirated. In 17 (39%) of these patients, fluid could not be obtained using traditional methods. Of these 17 failed attempts by traditional methods, 15 patients received ECUS in a "break" from the study protocol. Ascitic fluid was obtained in 13 of these 15 patients; of the 2 remaining patients, 1 did not have enough fluid to be sampled and the other had no fluid visualized.

CONCLUSION

Ninety-five percent (P=.0003) of the patients who were randomized in the ECUS group and in whom a needle paracentesis was performed had ascitic fluid successfully obtained, as compared with the traditional method group.

The efficacy of ultrasonography in hemodynamically stable children with blunt abdominal trauma: a prospective comparison with computed tomography

PURPOSE

In this prospective study we aimed to investigate the diagnostic value of ultrasonography (US) in hemodynamically stable children after blunt abdominal trauma (BAT) using computed tomography (CT) as the gold standard.

MATERIALS AND METHODS

Between 1997 and 2001, 96 children with BAT were evaluated prospectively. CT was performed first, followed by US. US and CT examinations were independently evaluated by two radiologists for free fluid and organ injury. The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of US were assessed regarding CT as the gold standard.

RESULTS

Overall 128 organ injuries were determined in 96 patients with CT; however, 20 (15.6%) of them could not be seen with US. Free intraabdominal fluid (FIF) was seen in 82 of 96 patients by CT (85.4%) and eight of them (9.7%) could not be seen by US. We found that sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of the US for free intra-abdominal fluid were 90.2, 100, 100, 63.6 and 91.7%, respectively.

CONCLUSIONS

US for BAT in children is highly accurate and specific. It is highly sensitive in detecting liver, spleen and kidney injuries whereas its sensitivity is moderate for the detection of gastrointestinal tract (GIT) and pancreatic injuries.

Emergency ultrasound in the acute assessment of haemothorax

AIMS

To evaluate thoracic ultrasound for the detection of haemothorax in patients with thoracic trauma against established investigations.

METHODS

Thoracic ultrasound was performed as an extension of the standard focused assessment with sonography for trauma (FAST) protocol used at the Queen's Medical Centre for the assessment of adult patients with torso trauma. Fluid was sought in both pleural cavities using a hand portable ultrasound system by one of two non-radiologists trained in FAST. Findings were compared against subsequent investigations/procedures performed at the discretion of the attending emergency physician-supine chest radiography, intercostal drain, computed tomography, or thoracotomy. The sensitivity of the technique and the time taken to diagnosis for each investigation were recorded.

RESULTS

Sixty one patients, 54 (89%) after blunt trauma, underwent thoracic ultrasound evaluation during the study. Twelve patients had a haemothorax detected by ultrasound and confirmed by computed tomography or by tube thoracostomy. Four haemothoraces detected on ultrasound were not apparent on trauma chest radiography. There were 12 true positives, 48 true negatives, no false positives, and one false negative scan. The sensitivity of ultrasound was 92% and specificity 100% with a positive predictive value of 100% and negative predictive value 98% for the detection of haemothorax after trauma.

CONCLUSIONS

Emergency ultrasound of the chest performed as part of the primary survey of the traumatised patient can rapidly and accurately diagnose haemothorax and is a valuable tool to augment the immediate clinical assessment of these patients.

[Shock trauma room diagnosis: initial diagnosis after blunt abdominal trauma. A review of the literature]

OBJECTIVE

Blunt abdominal trauma is most common in the polytraumatized patient and beside neurocranial trauma one major determinant of early death in these patients. Therefore, immediate recognition of an abdominal injury is of life-saving importance.

METHODS

Clinical trials were systematically collected (Medline, Cochrane and hand searches) and classified into evidence levels (1 to 5 according to the Oxford system).

RESULTS

Clinical examination is not reliable for evaluation of abdominal injury. Abdominal ultrasound, especially if only focusing on free fluid (FAST) is not sensitive enough. Today, CT-scan of the abdomen is the gold-standard in diagnosing abdominal injury. Diagnostic Peritoneal Lavage (DPL) has a high sensitivity but in our region only is used in exceptional cases. The patient with continuing hemodynamical instability after abdominal trauma and evidence of free intraperitonial fluid has to undergo laparotomy.

CONCLUSION

After blunt abdominal trauma, initially ultrasound investigation should be performed in the emergency room. This should not only focus on free intraabdominal fluid but also on organ lesions. Regardless of the findings from ultrasound or clinical examination, the hemodynamically stable patient should undergo a CT-scan of the abdomen in order to proof or exclude an abdominal injury.

Reevaluation of ultrasonography for solid-organ injury in blunt abdominal trauma

OBJECTIVE

To reevaluate the usefulness of ultrasonography for detecting and classifying solid-organ injuries from blunt abdominal trauma by comparing ultrasonography with computed tomography (CT) and laparotomy.

METHODS

Six hundred four patients with blunt abdominal trauma were examined by both B-mode ultrasonography and CT for a study period of 14 years. The ultrasonographic examiners were divided into 2 groups depending on their experience with ultrasonography. The ultrasonographic results were then compared with CT and surgical findings. This was a retrospective study.

RESULTS

In 198 patients, solid-organ injuries were identified on CT, laparotomy, or both. Sensitivity values in group A (experts) were 87.5% for hepatic injuries, 85.4% for splenic injuries, 77.6% for renal injuries, and 44.4% for pancreatic injuries. Sensitivity values in group B were 46.2% for hepatic injuries, 50.0% for splenic injuries, and 44.1% for renal injuries. The detection rates in group A were 80% to 100% for different types of hepatic injuries except superficial injuries (20%) and 70% to 100% for different types of splenic injuries. The detection rates for renal parenchymal and pancreatic duct injuries were 53.3% and 80%, respectively. The detection rates for injuries requiring intervention were 86.1% in group A and 66.7% in group B.

CONCLUSIONS

The sensitivity of ultrasonography with the use of CT and surgical findings as reference standards decreased compared with our prior study. However, ultrasonography was found to enable experienced examiners to detect and classify parenchymal injuries efficiently, despite disadvantages in detecting superficial and vascular injuries. Ultrasonography should be used to explore not only free fluid but also solid-organ injuries.

Evaluation of a focused assessment with sonography for trauma protocol to detect free abdominal fluid in dogs involved in motor vehicle accidents

OBJECTIVE

To establish a focused assessment with sonography for trauma (FAST) protocol in dogs, determine whether FAST can be performed by veterinary clinicians without extensive ultrasonographic experience, and assess the frequency of free fluid (as determined via FAST) in the abdominal cavity of dogs following motor vehicle accidents (MVAs).

DESIGN

Prospective study.

ANIMALS

100 client-owned dogs evaluated within 24 hours of an MVA.

PROCEDURE

Dogs were placed in lateral recumbency for the FAST examination. To detect fluid in the abdomen, 2 ultrasonographic views (transverse and longitudinal) were obtained at each of 4 sites (just caudal to the xiphoid process, on the midline over the urinary bladder, and at the left and right flank regions).

RESULTS

In the 100 dogs evaluated via FAST, free abdominal fluid was detected in 45 dogs. In 40 of those 45 dogs, abdominocentesis was performed; hemoperitoneum and uroperitoneum were diagnosed in 38 and 2 dogs, respectively. Compared with dogs that had no free abdominal fluid detected via FAST, dogs that had free abdominal fluid detected via FAST had significantly higher heart rates and serum lactate concentrations and significantly lower PCVs and total solid concentrations.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicate that FAST is a simple and rapid technique that can be performed on dogs in an emergency setting to detect intra-abdominal free fluid and can be performed by veterinary clinicians with minimal previous ultrasonographic experience.

Minimum training for right upper quadrant ultrasonography

The objective of this study was to assess if 10 right upper quadrant (RUQ) ultrasound (US) examinations could be used as a minimum standard for training. This was a retrospective review of patients with suspected gallbladder pathology who underwent resident-performed RUQ US before operative or department of radiology evaluation. Two hundred twenty-four patients were examined using resident-performed RUQ US followed by gold standard evaluations. One hundred seventy-eight patients were evaluated by 13 residents who met the "minimum training" standard of 10 prior examinations. The results of resident-performed RUQ US for gallstones and/or cholecystitis are shown subsequently. Previous suggestions that 10 examinations could be used as a minimum standard for training in focused abdominal sonography for trauma examinations cannot be used for RUQ US. The ACEP 2001 guidelines for 25 examinations are more consistent with the learning curve suggested by our data.

Performance of abdominal ultrasonography in blunt trauma patients with out-of-hospital or emergency department hypotension

STUDY OBJECTIVES

We determine the test performance of abdominal ultrasonography for detecting hemoperitoneum in blunt trauma patients with out-of-hospital or emergency department (ED) hypotension.

METHODS

We reviewed the medical records of all blunt trauma patients hospitalized at a Level I trauma center. Patients were included if they were older than 6 years and had out-of-hospital or ED hypotension (systolic blood pressure < or =90 mm Hg) and underwent ED ultrasonography. The initial interpretation of the abdominal ultrasonography was recorded, including the presence or absence of intraperitoneal fluid and the specific location of such fluid. Presence or absence of intra-abdominal injury was determined by abdominal computed tomography scan, laparotomy, or clinical follow-up.

RESULTS

Four hundred forty-seven patients with a mean age of 36.0+/-17.5 years were enrolled. One hundred forty-eight (33%) patients had intra-abdominal injuries, and 116 (78%) of these patients had hemoperitoneum. Abdominal ultrasonography had the following test performance for detecting patients with intra-abdominal injury and hemoperitoneum: sensitivity 92/116 (79%; 95% confidence interval [CI] 71% to 86%), specificity 316/331 (95%; 95% CI 93% to 97%), positive predictive value 92/107 (86%; 95% CI 78% to 92%), and negative predictive value 316/340 (93%; 95% CI 90% to 95%). The positive likelihood ratio was 15.8, and the negative likelihood ratio was 0.22. One hundred five (91%) of the 116 patients with intra-abdominal injuries and hemoperitoneum underwent a therapeutic laparotomy. Abdominal ultrasonography demonstrated intraperitoneal fluid in 87 (sensitivity 83%; 95% CI 74% to 90%) of these 105 patients.

CONCLUSION

Of patients with out-of-hospital or ED hypotension, abdominal ultrasonography identifies most patients with hemoperitoneum and intra-abdominal injuries. Hypotensive patients with negative abdominal ultrasonography results, however, must be further evaluated for sources of their hypotension, including additional abdominal evaluation, once they are hemodynamically stabilized.

Bedside echocardiography in chest trauma

Bedside US has an established role in the evaluation of chest trauma patients. Transthoracic echocardiography and TEE can be used to obtain critical information at the bedside for many emergent conditions, including the immediate detection of hemopericardium and acute aortic injury. More recent work has demonstrated that US also can be used to detect hemothoraces and pneumothoraces with accuracy. These diagnostic techniques can improve patient outcome and are within the scope of practice of emergency physicians and trauma surgeons. Physicians caring for trauma patients should be familiar with these techniques.

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

OBJECTIVES

To assess whether 10 focused abdominal sonography for trauma (FAST) examinations could be used as a minimum standard for training, as suggested previously.

METHODS

This was a retrospective review of patients with abdominal trauma who underwent resident-performed FAST examinations before surgical or Department of Radiology evaluation.

RESULTS

Six hundred ninety-eight patients were examined by resident-performed FAST followed by reference standard evaluations. Four hundred twelve patients were evaluated by residents who previously performed 10 FAST examinations; 154 were evaluated by 29 residents performing their 11th through 30th examinations; and 258 were evaluated by 10 residents performing their 31st and subsequent examinations. The results of resident-performed FAST for intraperitoneal free fluid were as follows: 11 to 20 examinations--sensitivity, 73.9% (95% confidence interval, 51.3%-88.9%); specificity, 98.8% (92.5%-99.9%); true-positive findings, 17; true-negative, 81; false-positive, 1; false-negative, 6; total patients, 105; 21 to 30 examinations--sensitivity, 100% (73.2%-100%); specificity, 97.1% (83.3%-99.9%); true-positive, 14; true-negative, 34; false-positive, 1; false-negative, 0; total patients, 49; 31 and more examinations--sensitivity, 94.8% (88.6%-97.9%); specificity, 98.6% (94.5%-99.8%); true-positive, 110; true-negative, 140; false-positive, 2; false-negative, 6; total patients, 258.

CONCLUSIONS

The suggestion that 10 examinations could be used as a minimum standard for training in FAST examinations was not validated.

Trauma in pregnancy

The anatomic and physiologic changes make treatment of the pregnant trauma patient complex. The fetus is the challenge, because, in pregnancy, trauma has little effect on maternal morbidity and mortality. Aggressive resuscitation of the mother, in general, is the best management for the fetus, because fetal outcome is directly related to maternal outcome. Recent literature has attempted, with little success, to identify factors that may predict poor fetal outcomes. Cardiotocographic monitoring should be initiated as soon as possible in the emergency department to evaluate fetal well-being. Other key points include: Maternal blood pressure and respiratory rate return to baseline as pregnancy approaches term. Initial fetal health may be the best indicator of maternal health. Inferior vena cava compression in the supine patient may cause significant hypotension. Maternal acidosis may be predictive of fetal outcome. Kleihauer-Betke testing is not necessary in the emergency department. Early ultrasonographic evaluation can identify free intraperitoneal fluid and assess fetal health. Necessary radiographs should not be withheld at any period of gestation. Radiation beyond 20 weeks' gestation is safe. Patients with viable gestations require at least 4 hours of CTM monitoring after even minor trauma.

Unusual case of acute onset abdominal pain: uses and limitations of medical imaging

A 28-year-old male with atraumatic abdominal pain and transient hypotension was assessed using bedside emergency department (ED) ultrasonography and contrast enhanced helical computed tomography (CT). Both tests revealed free intraperitoneal fluid, but neither detected a splenic defect. The patient subsequently underwent splenectomy for a ruptured spleen. His serology for typical viral causes was negative. This article discusses spontaneous splenic rupture, the role of imaging in diagnosis, and the limitations of ED ultrasound and contrast enhanced helical CT.

Goal-directed abdominal ultrasonography: impact on real-time decision making in the emergency department

The impact of "goal-directed" abdominal ultrasound (US) on real-time decision making in the emergency department (ED) was studied, with specific emphasis on the certainty of diagnosis, treatment, and disposition plans. A prospective, interventional study enrolled 212 patients at a county teaching hospital ED, who underwent bedside US by experienced ED sonographers. A study questionnaire was completed documenting the US indication, working diagnosis, treatment, and disposition plan. The physicians assigned pre-test and post-test levels of certainty for the diagnosis, treatment plan, and disposition on an integral scale from 1 to 10. Scores for diagnosis were further categorized into low (1-3), moderate (4-7) and high certainty of disease. Absolute mean changes in level of certainty for diagnosis, treatment, and disposition were 3.2 (95% CI 3.1-3.3), 2.0 (95% CI 1.9-2.1), and 1.9 (95% CI 1.8-2.0), respectively. The direction of change after US for certainty of diagnosis was evenly split, with 47% increasing and 47% decreasing. The majority of patients categorized as either high or low certainty of disease had US results concordant with the physician's initial assessment. However, 16% moved from either high to low or from low to high certainty categories after US. Patients with moderate certainty moved evenly to either the low or high post-test category in 97% of cases. Treatment and disposition decisions were less impacted by US, with the majority of cases increasing in certainty irrespective of the US results. Bedside ultrasonography in the ED has an important impact on real-time decision-making, particularly in terms of the certainty of diagnosis.