Early detection of hemoperitoneum by ultrasound examination of the right upper quadrant: a multicenter study

Extended Focused Assessment with Sonography for Trauma in the Emergency Department: A Comprehensive Review

The Extended Focused Assessment with Sonography for Trauma (eFAST) plays a crucial role in the emergency department (ED) by providing rapid and non-invasive diagnostic information in trauma patients. It is a diagnostic-free fluid detection technique that uses sonography to assess trauma in different anatomical windows of the chest and abdomen and has been accepted in multiple studies as the initial diagnostic tool for torso injuries in blunt abdominal trauma. By promptly identifying potentially life-threatening injuries, such as haemoperitoneum, haemothorax, and cardiac tamponade, eFAST facilitates timely intervention and improves patient outcomes in the ED. The eFAST exam is reliable, with high sensitivity and specificity, even when performed by non-radiological personnel, saving time and resources in the chaotic emergency environment. This review aims to assess the diagnostic reliability and limitations of eFAST in different trauma conditions and to outline its goals in trauma critical care and in "ABCDE" resuscitation.

Witnessed prehospital traumatic arrest: predictors of survival to hospital discharge

PURPOSE

Trauma patients are rapidly transported to the hospital for definitive care. Nonetheless, some are alive upon Emergency Medical Services (EMS) arrival but arrest on-scene or during transport. The study objective was to examine EMS-witnessed traumatic arrests to define patients who survived hospital discharge.

METHODS

Patients sustaining EMS-witnessed traumatic arrest and entered into the National Trauma Data Bank were included (2007-2018). Mortality defined groups: survival to hospital discharge vs. in-hospital death vs. death in ED/declared dead on arrival (DOA). ANOVA/Chi-square compared cohorts. Multivariable analysis established factors associated with survival out of ED and to hospital discharge.

RESULTS

After exclusions, 14,177 patients met the criteria: 10% survived, 22% died in hospital, and 68% died in ED/DOA. Survivors tended to be female (33% vs. 23% vs. 23%, p < 0.001), blunt traumas (71% vs. 56% vs. 60%, p < 0.001), have higher scene GCS (15 [7-15] vs. 3 [3-11] vs. 3 [3-7], p < 0.001), and lower injury severity (ISS 13 [7-26] vs. 27 [18-41] vs. 25 [10-30], p < 0.001), particularly of the head (AIS 0 [0-2] vs. 0 [0-4] vs. 1 [0-4], p < 0.001). Survival to hospital discharge was independently associated with higher field GCS (OR 1.252, p < 0.001) and SBP (OR 1.006, p < 0.001), and Head AIS scores (OR 1.073, p < 0.001). Increasing age (OR 0.984, p < 0.001), higher ISS (OR 0.975, p < 0.001), male sex (OR 0.695, p < 0.001), and penetrating mechanism of injury (OR 0.537, p < 0.001) were associated with reduced survival to discharge.

CONCLUSION

After EMS-witnessed traumatic cardiac arrest, survivors were more likely to be young, female, injured by blunt trauma, and less hypotensive/comatose on-scene. These findings may have implications for ED resuscitation or declaration of care futility and should be further investigated with a prospective multicenter study.

Regional anesthesia and POCUS in the intensive care unit

This chapter focuses on resident recruitment and recent US National Resident Matching Program changes and the impact in the evaluation and ranking of applicants within the specialty of anesthesiology. Recruitment challenges are examined as well as program strategies and potential future directions. Also discussed are DEI initiatives within the recruitment process.

Use of Automated Machine Learning for Classifying Hemoperitoneum on Ultrasonographic Images of Morrison's Pouch: A Multicenter Retrospective Study

This study evaluated automated machine learning (AutoML) in classifying the presence or absence of hemoperitoneum in ultrasonography (USG) images of Morrison's pouch. In this multicenter, retrospective study, 864 trauma patients from trauma and emergency medical centers in South Korea were included. In all, 2200 USG images (1100 hemoperitoneum and 1100 normal) were collected. Of these, 1800 images were used for training and 200 were used for the internal validation of AutoML. External validation was performed using 100 hemoperitoneum images and 100 normal images collected separately from a trauma center that were not included in the training and internal validation sets. Google's open-source AutoML was used to train the algorithm in classifying hemoperitoneum in USG images, followed by internal and external validation. In the internal validation, the sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve were 95%, 99%, and 0.97, respectively. In the external validation, the sensitivity, specificity, and AUROC were 94%, 99%, and 0.97, respectively. The performances of AutoML in the internal and external validation were not statistically different (p = 0.78). A publicly available, general-purpose AutoML can accurately classify the presence or absence of hemoperitoneum in USG images of the Morrison's pouch of real-world trauma patients.

Using Right-Sided Roll to Improve Reliability of Focused Assessment with Sonography in Trauma: An Eastern Association for the Surgery of Trauma Multicenter Prospective Study

BACKGROUND

The Focused Assessment Sonography in Trauma (FAST) examination is the standard of care for detecting hemoperitoneum in hypotensive blunt trauma patients. A pilot study demonstrated earlier identification of intra-abdominal fluid via FAST after right-sided roll (FASTeR) when compared with the standard FAST. The purpose of this study was to evaluate this phenomenon prospectively in hypotensive blunt trauma patients.

STUDY DESIGN

An Eastern Association for the Surgery of Trauma-approved multicenter prospective trial was performed June 2016 to October 2020 at 8 designated trauma centers. Hypotensive adult blunt trauma patients were included. A traditional FAST examination was performed. After this, the secondary survey logroll for back examination was standardized to the patient's right side. A repeat supine right upper quadrant ultrasound view was obtained. The presence or absence of hemoperitoneum was confirmed by CT scan or intraoperative findings. FAST and FASTeR were compared using receiver operating characteristics. The area under the curve was calculated.

RESULTS

A total of 182 patients met inclusion criteria. A total of 65 patients (35.7%) had hemoperitoneum on CT scan or intraoperative findings. The sensitivity of FASTeR was 47.7%, and of FAST was 40.0% (p = 0.019). The receiver operating characteristics area under the curve of the FASTeR examination was 0.717 vs 0.687 for the FAST examination (p = 0.091).

CONCLUSIONS

Addition of a right upper quadrant view after right-sided roll does improve the sensitivity of the FAST examination while maintaining the standard positive predictive value. We demonstrate a trend that does not reach statistical significance about the overall accuracy. This multicenter prospective trial was underpowered to reveal a statistically significant difference in the overall accuracy as measured by the receiver operating characteristics area under the curve.

Point of Care Ultrasound Literature Primer: Key Papers on Focused Assessment With Sonography in Trauma (FAST) and Extended FAST

Objective

The objective of this study is to identify the top five most influential papers published on focused assessment with sonography in trauma (FAST) and the top five most influential papers on the extended FAST (E-FAST) in adult patients.

Methods

An expert panel was recruited from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative. These experts are ultrasound fellowship-trained or equivalent, are involved with point-of-care ultrasound (POCUS) research and scholarship, and are leaders in both the POCUS program at their local site and within the national Canadian POCUS community. This 14-member expert group used a modified Delphi process consisting of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers for FAST and E-FAST.

Results

The expert panel identified 56 relevant papers on FAST and 40 relevant papers on E-FAST. After completing all three rounds of the modified Delphi process, the authors identified the top five most influential papers on FAST and the top five most influential papers on E-FAST.

Conclusion

We have developed a reading list of the top five influential papers for FAST and E-FAST that will benefit residents, fellows, and clinicians who are interested in using POCUS in an evidence-informed manner.

Development of a Consensus-Based Definition of Focused Assessment With Sonography for Trauma in Children

Importance

The wide variation in the accuracy and reliability of the Focused Assessment With Sonography for Trauma (FAST) and the extended FAST (E-FAST) for children after blunt abdominal trauma reflects user expertise. FAST and E-FAST that are performed by experts tend to be more complete, better quality, and more often clinically valuable.

Objective

To develop definitions of a complete, high-quality, and accurate interpretation for the FAST and E-FAST in children with injury using an expert, consensus-based modified Delphi technique.

Design, Setting, and Participants

This consensus-based qualitative study was conducted between May 1 to June 30, 2021. It used a scoping review and iterative Delphi technique and involved 2 rounds of online surveys and a live webinar to achieve consensus among a 26-member panel. This panel consisted of international experts in pediatric emergency point-of-care ultrasonography.

Main Outcomes and Measures

Definitions of complete, high-quality, and accurate FAST and E-FAST studies for children after injury.

Results

Of the 29 invited pediatric FAST experts, 26 (15 men [58%]) agreed to participate in the panel. All 26 panelists completed the 2 rounds of surveys, and 24 (92%) participated in the live and asynchronous online discussions. Consensus was reached on FAST and E-FAST study definitions, and the panelists rated these 5 anatomic views as important and appropriate for a complete FAST: right upper-quadrant abdominal view, left upper-quadrant abdominal view, suprapubic views (transverse and sagittal), and subxiphoid cardiac view. For E-FAST, the same FAST anatomic views with the addition of the lung or pneumothorax view were deemed appropriate and important. In addition, the panelists rated a total of 32 landmarks as important for assessing completeness. Similarly, the panelists rated 14 statements on quality and 20 statements on accurate interpretation as appropriate.

Conclusions and Relevance

This qualitative study generated definitions for complete FAST and E-FAST studies with high image quality and accurate interpretation in children with injury. These definitions are similar to those in adults with injury and may be used for future education, quality assurance, and research. Future research may focus on interpretation of trace volumes of abdominal free fluid and the use of serial FAST.

Helicopter Emergency Medical Services Performed Extended Focused Assessment With Sonography: Training, Workflow, and Sustainable Quality

The extended focused assessment of trauma (EFAST) examination is an invaluable tool for the initial evaluation of the trauma patient. Miniaturization of ultrasound has enabled helicopter emergency medical services (HEMS) to use point-of-care ultrasound to care for trauma patients on scene. Our study demonstrated that HEMS crews accurately performed EFAST examinations after the implementation of a novel HEMS EFAST workflow, multifaceted training, and ongoing quality assurance. The HEMS crews' overall sensitivity was 53%, and specificity was 98%. The obtained image quality was highest for the lung, cardiac, and right upper quadrant components of the EFAST. Our results suggest that with a structured multifaceted training program, user-friendly workflow, and ongoing quality assurance, HEMS crews can perform EFAST examinations safely and reliably in the field. This would allow HEMS crews to detect life-threatening, time-sensitive conditions such as a pneumothorax, pericardial effusion, and intraperitoneal hemorrhage. HEMS EFAST has the potential to triage certain trauma patients directly to the operating room or newly emerging hybrid suites, bypassing the emergency room and saving crucial time.

The use of ultrasound in the acute setting: Lessons learned after 30 years

This article describes the key events in the evolution of the surgeon's use of ultrasound for the evaluation of patients. The lessons learned may be relevant in the future as the issues encountered with the adoption of ultrasound by surgeons may be revisited.

Hepatobiliary and pancreatic hemorrhage: Technical tools and tricks

Ongoing hemorrhage from hepatobiliary and pancreatic injuries continues to daunt even the most experienced surgeon. Despite the widespread centralization of elective hepatopancreatobiliary (HPB) surgery to high-volume centers, HPB trauma remains relatively common and requires a rapid and thoughtful approach [[1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13]].

Differences in Gaze Fixation Location and Duration Between Resident and Fellowship Sonographers Interpreting a Focused Assessment With Sonography in Trauma

OBJECTIVES

We quantified the gaze fixation duration of resident and fellowship sonographers interpreting a prerecorded focused assessment with sonography in trauma (FAST). We hypothesized that all sonographers would fixate on each relevant anatomic relationship but that the duration of fixation would differ.

METHODS

We conducted a cross-sectional study collecting and analyzing the gaze fixations of a convenience sample of current resident and fellowship sonographers. All sonographers viewed a standardized FAST video, and their gaze fixations were recorded using a Tobii X3-120 eye-tracking bar. Gaze fixations over nine anatomic regions of interest (ROIs) were identified. These were assessed for normality and analyzed using the Wilcoxon rank sum test at an alpha of 0.05 and Bonferroni correction p value of <0.0034. The chi-square test and Pearson's correlation were performed to assess statistical association.

RESULTS

The gaze fixation recordings of 24 resident and eight fellowship sonographers were suitable for analysis. Fourteen of the 24 resident sonographers viewed all ROIs in the FAST, whereas all eight fellowship sonographers viewed each of the nine relevant ROIs. Five ROIs were identified over which at least one resident sonographer did not have a gaze fixation. No statistically significant difference was identified between groups. Resident sonographers gaze fixated over the left upper quadrant (LUQ) splenorenal interface for a median (interquartile range) of 10.64 (9.73-11.60) seconds. The fellowship group viewed the same ROI for 8.43 (6.64-8.95) seconds (p < 0.003). All participants viewed this ROI. No other ROIs had a statistical difference.

CONCLUSION

Five ROIs were identified that were not visually interrogated by all resident sonographers. Only 14 of 24 resident sonographers visually interrogated every area in the FAST, whereas all fellowship sonographers interrogated every ROI. A statistically significant difference was found in gaze fixation duration between resident and fellowship sonographers in one ROI. Further study is required for gaze fixation assessment to become a tool for the interpretation component of point-of-care ultrasound.

Flat Inferior Vena Cava: Indicator of Poor Prognosis in Trauma and Acute Care Surgery Patients

Flat inferior vena cava (IVC) on ultrasound examination has been shown to correlate with hypovolemic status. We hypothesize that a flat IVC on limited echocardiogram (LTTE) performed in the emergency room (ER) correlates with poor prognosis in acutely ill surgical patients. We conducted a retrospective review of all patients undergoing LTTE in the ER from September 2010 until June 2011. IVC diameter was estimated by subxiphoid window. Flat IVC was defined as diameter less than 2 cm. Fat IVC was defined as diameter greater than 2 cm. Need for intensive care unit admission, blood transfusion requirement, mortality, and need for emergent operation between patients with flat versus Fat IVC were compared. One hundred one hypotensive patients had LTTE performed in the ER. Average age was 38 years. Admission diagnosis was blunt trauma (n = 80), penetrating trauma (n = 13), acute care surgery pathology (n = 7), and burn (n = 1). Seventy-four patients had flat IVC on initial LTTE. Compared with those with fat IVC, flat patients were found have higher rates of intensive care unit admission (51.3 vs 14.8%; P = 0.001), blood transfusion requirement (12.2 vs 3.7%), and mortality (13.5 vs 3.7%). This population also underwent emergent surgery on hospital Day 1 more often (16.2 vs 0%; P = 0.033). Initial flat IVC on LTTE is an indicator of hypovolemia and a predictor of poor outcome.

Rolling a trauma patient onto the right side increases sensitivity of FAST examination

PURPOSE

Hemoperitoneum in the hypotensive trauma patient is an indication for emergent laparotomy. Focused assessment sonography in trauma (FAST) is a widely used tool for detecting hemoperitoneum. The usefulness of FAST is currently limited by low sensitivity. We hypothesize rolling patients onto their right side will pool small volumes of fluid into the right upper quadrant of the abdomen leading to increased sensitivity.

METHODS

Peritoneal dialysis patients were recruited for voluntary participation in a small pilot prospective clinical trial. Each participant first underwent a supine FAST followed by a 30-second roll onto the right side. Once back in the supine position, the FAST was repeated (FASTeR or FAST examination after right-sided roll). About 50 mL aliquots of dialysate were sequentially infused into the abdomen and the imaging sequence repeated until a positive finding was obtained.

RESULTS

Seven patients were consented for the study. One patient was found to have an equivocal examination secondary to renal cysts. All six remaining participants converted to a positive FASTeR at an intra-abdominal fluid volume at which standard FAST was negative.

CONCLUSIONS

Rolling patients to the right side increased FAST sensitivity, converting false-negative to true positives examinations. A larger study is needed to validate our preliminary data.

Prehospital ultrasound in the management of trauma patients: Systematic review of the literature

INTRODUCTION

Emergency ultrasound methods such as Focused Assessment with Sonography in Trauma (FAST) are a widely used imaging method. This examination can be performed to examine the presence of several life-threatening injuries. Early diagnosis may lead to better outcome, but the effect of timely diagnosis in the prehospital setting is not yet clear. Therefore, the aim is to determine the diagnostic accuracy and the effect of prehospital ultrasound performed in (poly)trauma patients.

METHODS

A literature search was performed in PubMed, Embase and Cochrane's Library. Articles were included if prehospital ultrasound was performed as a diagnostic intervention in patients with trauma. The main outcome measures included diagnostic accuracy, changes in prehospital diagnosis/treatment, changes in destination hospital and in-hospital response. Case reports and case series were excluded.

RESULTS

After screening 3343 articles, nine studies met the inclusion criteria. These included three retrospective and six prospective observational studies, with a total number of 2,889 patients. Five studies report at least one change in polytrauma management, ranging from 6% to 48,9% of the cases. The diagnostic accuracy of prehospital ultrasound was adequate in eight (out of nine) articles. High sensitivity and high specificity were found on several endpoints (pneumothorax, free abdominal fluid, haemoperitoneum, both on site and during transport).

CONCLUSION

Prehospital ultrasound led to a change in polytrauma management in all studies that included this as an outcome measure. The diagnostic accuracy was described in eight studies, high sensitivity and specificity were found. Overall, the studies seem to suggest a positive influence of performing ultrasound. However, additional research with homogenous accuracy endpoints and uniformly trained prehospital care providers is recommended.

Is E-FAST possible and useful on the battlefield? A feasibility study during medical courses in hostile environment (MEDICHOS): preliminary results

Introduction

The extent of the French forces’ territory in the Sahel band generates long medical evacuations. In case of many victims, to respect the golden hour rule, first-line sorting is essential. Through simulation situations, the aim of our study was to assess whether the use of ultrasound was useful to military doctors.

Methods

In combat-like exercise conditions, we provided trainees with a pocket-size ultrasound. Every patient for whom the trainees chose to perform ultrasound in role 1 was included. An extended focused assessment with sonography for trauma (E-FAST) was performed with six basic sonographic views. We evaluated whether these reference views were obtained or not. Once obtained by the trainees, pathological views corresponding to the scenario were shown to assess whether the trainees modified their therapeutic management strategy and their priorities.

Results

168 patients were treated by 15 different trainee doctors. Of these 168 patients, ultrasound (E-FAST or point-of-care ultrasound) was performed on 44 (26%) of them. In 51% (n=20/39) of the situations, the practitioners considered that the realisation of ultrasound had a significant impact in terms of therapeutic and evacuation priorities. More specifically, it changed therapeutic decisions in 67% of time (n=26/39) and evacuation priorities in 72% of time (n=28/39).

Conclusion

This original work showed that ultrasound on the battlefield was possible and useful. To confirm these results, ultrasound needs to be democratised and assessed in a real operational environment.

Focused assessment with sonography in trauma (FAST) for the regional anesthesiologist and pain specialist

This article in our point-of-care ultrasound (PoCUS) series is dedicated to the role the focused assessment with sonography in trauma (FAST) exam plays for the regional anesthesiologist and pain specialists in the perioperative setting. The FAST exam is a well-established and extensively studied PoCUS exam in both surgical and emergency medicine literature with over 20 years demonstrating its benefit in identifying the presence of free fluid in the abdomen following trauma. However, only recently has the FAST exam been shown to be beneficial to the anesthesiologist in the perioperative setting as a means to identify the extravasation of free fluid into the abdomen from the hip joint following hip arthroscopy. In this article, we will describe how to obtain the basic FAST views (subcostal four-chamber view, perihepatic right upper quadrant view, perisplenic left upper quadrant view, and pelvic view in the longitudinal and short axis) as well as cover the relevant sonoanatomy. We will describe pathological findings seen with the FAST exam, primarily free fluid in the peritoneal space as well as in the pericardial sac. As is the case with any PoCUS skill, the application evolves with understanding and utilization by new clinical specialties. Although this article will provide clinical examples of where the FAST exam is beneficial to the regional anesthesiologist and pain specialist, it also serves as an introduction to this powerful PoCUS skill in order to encourage clinical practitioners to expand the application of the FAST exam within the scope of regional anesthesia and pain management practice.

The focused assessment with sonography in trauma (FAST) in hypotensive injured patients frequently fails to identify the need for laparotomy: a multi-institutional pragmatic study

Background

The ability of focused assessment with sonography for trauma (FAST) to detect clinically significant hemorrhage in hypotensive injured patients remains unclear. We sought to describe the sensitivity and specificity of FAST using findings at laparotomy as the confirmatory test.

Methods

Patients from the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study that had a systolic blood pressure < 90mm Hg and underwent FAST were analysed. Results were compared with findings at laparotomy. A therapeutic laparotomy (T-LAP) was defined as an abdominal operation within 6 hours in which a definitive procedure was performed. The sensitivity and specificity of FAST were calculated.

Results

The cohort included 317 patients that underwent FAST (108 positive, 209 negative). T-LAP was performed in 69% (n=75) of FAST(+) patients and 22% (n=48) of FAST(−) patients. FAST had a sensitivity of 62% and specificity of 83%.

Conclusions

In our multicenter cohort, 22% of FAST(−) patients underwent T-LAP within 6 hours of admission. In hypotensive patients with a negative FAST, clinicians should still maintain a high index of suspicion for significant abdominal hemorrhage.

Level of evidence

Level IV.

Kidney Detection in 3-D Ultrasound Imagery via Shape-to-Volume Registration Based on Spatially Aligned Neural Network

This paper introduces a computer-aided kidney shape detection method suitable for volumetric (3D) ultrasound images. Using shape and texture priors, the proposed method automates the process of kidney detection, which is a problem of great importance in computer-assisted trauma diagnosis. This paper introduces a new complex-valued implicit shape model, which represents the multiregional structure of the kidney shape. A spatially aligned neural network classifiers with complex-valued output is designed to classify voxels into background and multiregional structure of the kidney shape. The complex values of the shape model and classification outputs are selected and incorporated in a new similarity metric, such as the shape-to-volume registration process only fits the shape model on the actual kidney shape in input ultrasound volumes. The algorithm's accuracy and sensitivity are evaluated using both simulated and actual 3-D ultrasound images, and it is compared against the performance of the state of the art. The results support the claims about accuracy and robustness of the proposed kidney detection method, and statistical analysis validates its superiority over the state of the art.

Focused assessment with sonography in trauma: a review of concepts and considerations for anesthesiology

The use of point-of-care ultrasound in trauma provides diagnostic clarity and routinely influences management. A scanning protocol known as the Focused Assessment with Sonography in Trauma (FAST) has been widely adopted by trauma providers of all specialties. The FAST exam addresses a broad array of pathologic conditions capable of causing instability, including hemoperitoneum, hemopericardium, hemothorax, and pneumothorax. The exam is an integral component to the primary assessment of injured patients and an iconic application of point-of-care ultrasound.This review article aims to summarize the application of the FAST exam with special consideration, where relevant, to anesthesiologists. The scope of the FAST exam, technical considerations, and clinical decision-making in trauma are explored.

The surgeon-performed ultrasound: a curriculum to improve residents' basic ultrasound knowledge

BACKGROUND

Despite the development of ultrasound courses by the American College of Surgeons two decades ago, many residencies lack formal ultrasound training. The aim of this study was to assess the previous ultrasound experience of residents and the efficacy of a new ultrasound curriculum by comparing pre- and post-course tests.

METHODS

A pre-course survey and test were sent to all residents at the University of Texas Southwestern Medical Center. Pre-interns and junior residents received a didactic lecture on ultrasound basics and the extended focused assessment with sonography for trauma and were given hands-on practice. Finally, a post-course test and survey were sent to the pre-interns and junior residents.

RESULTS

Only 11.3% of the residents reported having previous exposure to a formal ultrasound curriculum, and only 12.7% were taught by faculty. On the pre-course test, there was no difference in performance among senior residents, junior residents, and pre-interns (P = 0.114). After taking the course, the pre-interns improved their performance, and their average increased from 44.3% (standard deviation = 12.4%) to 66.1% (standard deviation = 12.2%; P < 0.001). The junior residents also had an improvement in their performance on the test after the course (P < 0.001). Junior residents performed better than pre-interns on the post-course test (P = 0.001).

CONCLUSIONS

The knowledge of surgical residents in ultrasound basics and extended focused assessment with sonography for trauma can be improved with the establishment of an ultrasound curriculum. We believe that such an educational endeavor should be encouraged by all surgical residencies.

Caudal Edge of the Liver in the Right Upper Quadrant (RUQ) View Is the Most Sensitive Area for Free Fluid on the FAST Exam

Introduction

The focused assessment with sonography in trauma (FAST) exam is a critical diagnostic test for intraperitoneal free fluid (FF). Current teaching is that fluid accumulates first in Morison’s pouch. The goal of this study was to evaluate the “sub-quadrants” of traditional FAST views to determine the most sensitive areas for FF accumulation.

Methods

We analyzed a retrospective cohort of all adult trauma patients who had a recorded FAST exam by emergency physicians at a Level I trauma center from January 2012 – June 2013. Ultrasound fellowship-trained faculty with three emergency medicine residents reviewed all FAST exams. We excluded studies if they were incomplete, of poor image quality, or with incorrect medical record information. Positive studies were assessed for FF localization, comparing the traditional abdominal views and on a sub-quadrant basis: right upper quadrant (RUQ)1 - hepato-diaphragmatic; RUQ2 - Morison’s pouch; RUQ3 - caudal liver edge and superior paracolic gutter; left upper quadrant (LUQ)1 - splenic-diaphragmatic; LUQ2 - spleno-renal; LUQ3 – around inferior pole of kidney; suprapubic area (SP)1 - bilateral to bladder; SP2 - posterior to bladder; SP3 – posterior to uterus (females). FAST results were confirmed by chart review of computed tomography results or operative findings.

Results

Of the included 1,008 scans, 48 (4.8%) were positive. The RUQ was the most positive view with 32/48 (66.7%) positive. In the RUQ sub-quadrant analysis, the most positive view was the RUQ3 with 30/32 (93.8%) positive.

Conclusion

The RUQ is most sensitive for FF assessment, with the superior paracolic gutter area around the caudal liver edge (RUQ3) being the most positive sub-quadrant within the RUQ.

Pediatric emergency medicine point-of-care ultrasound: summary of the evidence

The utility of point-of-care ultrasound is well supported by the medical literature. Consequently, pediatric emergency medicine providers have embraced this technology in everyday practice. Recently, the American Academy of Pediatrics published a policy statement endorsing the use of point-of-care ultrasound by pediatric emergency medicine providers.  To date, there is no standard guideline for the practice of point-of-care ultrasound for this specialty. This document serves as an initial step in the detailed "how to" and description of individual point-of-care ultrasound examinations.  Pediatric emergency medicine providers should refer to this paper as reference for published research, objectives for learners, and standardized reporting guidelines.

Shape-based kidney detection and segmentation in three-dimensional abdominal ultrasound images

Due to recent technical advancements of three-dimensional ultrasound imaging systems, applications of this imaging modality have been expanding from the fetal imaging to cardiac- and abdominal-diagnosis. Among all internal organs, diagnosing the kidney has a paramount importance for rapid bedside treatment of trauma and kidney stone patients using ultrasound images. Although three-dimensional ultrasound provides higher level of structural information of kidneys, manual kidney diagnosis using three-dimensional ultrasound images requires a highly trained medical staff, due to the extensive visual complexity which three-dimensional images contain. Therefore, computer aided automated kidney diagnosis becomes very essential. Due to the challenging problems of ultrasound images, such as speckle noise and inhomogeneous intensity profile, kidney segmentation in three-dimensional ultrasound images has not been sufficiently investigated by researchers. In this paper, we first propose a new automated kidney detection approach using three-dimensional Morison's pouch ultrasound images. Then, we proposed a shape-based method to segment the detected kidneys. A preprocessing step is utilized to overcome the ultrasound challenges. Based on a set of 14 ultrasound volumes, we have evaluated the detection rate of our proposed kidney detection approach which is 92.86%. For kidney segmentation, we compared our proposed method with an existing approach, and the performed statistical analysis strongly validates the superiority of our proposed method with p = 0.000032.

Prehospital ultrasound of the abdomen and thorax changes trauma patient management: A systematic review

BACKGROUND

Ultrasound examination of trauma patients is increasingly performed in prehospital services. It is unclear if prehospital sonographic assessments change patient management: providing prehospital diagnosis and treatment, determining choice of destination hospital, or treatment at the receiving hospital.

OBJECTIVE

This review aims to assess and grade the evidence that specifically examines whether prehospital ultrasound (PHUS) of the thorax and/or abdomen changes management of the trauma patient.

METHODS

A systematic review was conducted of trauma patients who had an ultrasound of the thorax or abdomen performed in the prehospital setting. PubMed, MEDLINE, Web of Science (CINAHL, EMBASE, Cochrane Central Register of Controlled Trials) and the reference lists of included studies were searched. Methodological quality was checked and risk of bias analysis performed, a level of evidence grade was assigned, and descriptive data analysis performed.

RESULTS

992 unique citations were identified, which included eight studies that met inclusion criteria with a total of 925 patients. There are no reports of randomised controlled trials. Heterogeneity exists between the included studies which ranged from a case series to retrospective and prospective non-randomised observational studies. Three studies achieved a 2+ Scottish Intercollegiate Guidelines Networks grade for quality of evidence and the remainder demonstrated a high risk of bias. The three best studies each provided examples of prehospital ultrasound positively changing patient management.

CONCLUSION

There is moderate evidence that supports prehospital physician use of ultrasound for trauma patients. For some patients, management was changed based on the results of the PHUS. The benefit of ultrasound use in non-physician services is unclear.

Do we really rely on fast for decision-making in the management of blunt abdominal trauma?

INTRODUCTION

The Focused Assessment with Sonography in Trauma examination (FAST) is currently taught and recommended in the ATLS(®), often as an addendum to the primary survey for patients with blunt abdominal trauma. Although it is non-invasive and rapidly performed at bedside, the utility of FAST in blunt abdominal trauma has been questioned. We designed this study to examine our hypothesis that FAST is not an efficacious screening tool for identifying intra-abdominal injuries.

METHODS

We performed a retrospective chart review of all patients with confirmatory diagnosis of blunt abdominal injuries with CT and/or laparotomy for a period of 1.5 years (from 7/2009 to 11/2010). FAST was performed by ED residents and considered positive when free intra-abdominal fluid was visualized. Abdominal CT, or exploratory laparotomy findings were used as confirmation of intra-abdominal injury.

RESULTS

A total of 1671 blunt trauma patients were admitted to and evaluated in the Emergency Department during a 1½ year period and 146 patients were confirmed intra-abdominal injuries by CT and/or laparotomy. Intraoperative findings include injuries to the liver, spleen, kidneys, and bowels. In 114 hemodynamically stable patients, FAST was positive in 25 patients, with a sensitivity of 22%. In 32 hemodynamically unstable patients, FAST was positive in 9 patients, with a sensitivity of 28%. A free peritoneal fluid and splenic injury are associated with a positive FAST on univariate analysis, and are the independent predictors for a positive FAST on multiple logistic regression.

CONCLUSION

FAST has a very low sensitivity in detecting blunt intraabdominal injury. In hemodynamically stable patients, a negative FAST without a CT may result in missed intra-abdominal injuries. In hemodynamically unstable blunt trauma patients, with clear physical findings on examination, the decision for exploratory laparotomy should not be distracted by a negative FAST.

Atlas-based segmentation of abdominal organs in 3D ultrasound, and its application in automated kidney segmentation

Automated segmentation of abdominal organs in 3D ultrasound images is an important and challenging task toward computer assisted emergency diagnosis. However, speckle noise, low-contrast organ tissues, intensity-profile inhomogeneity, and partial organ visibility are some ultrasound challenges which limits the utility of the automated diagnosis solutions. In this paper, an atlas-based method to automatically segment an organ of interest in abdominal 3D ultrasound images is proposed. The atlas model contains texture information and shape knowledge of the organ, which facilitates an accurate discrimination of organ from non-organ voxels in input 3D ultrasound images. The proposed method offers a mechanism to automatically detect the organ, and therefore, it eliminates the need of manual initialization of organ segmentation. The proposed method is applied to automatically segment the right kidney in 3D ultrasound images. The experimental results indicate that the proposed method provides a higher detection and segmentation accuracy compared to state-of-the-art.

Use of the focused assessment with sonography for trauma (FAST) examination and its impact on abdominal computed tomography use in hemodynamically stable children with blunt torso trauma

BACKGROUND

The aim of this study was to evaluate the variability of clinician-performed Focused Assessment with Sonography for Trauma (FAST) examinations and its impact on abdominal computed tomography (AbCT) use in hemodynamically stable children with blunt torso trauma (BTT). The FAST is used with variable frequency in children with BTT.

METHODS

We performed a planned secondary analysis of children (<18 years) with BTT. Patients with a Glasgow Coma Scale (GCS) score of less than 9, those with hypotension, and those taken directly to the operating suite were excluded. Clinicians documented their suspicion for intra-abdominal injury (IAI) as very low, less than 1%; low, 1% to 5%; moderate, 6% to 10%; high, 11% to 50%; or very high, greater than 50%. We determined the relative risk (RR) for AbCT use based on undergoing a FAST examination in each of these clinical suspicion strata.

RESULTS

Of 6,468 (median age, 11.8 years; interquartile range, 6.3-15.5 years) children who met eligibility, 887 (13.7%) underwent FAST examination before CT scan. A total of 3,015 (46.6%) underwent AbCT scanning, and 373 (5.8%) were diagnosed with IAI. Use of the FAST increased as clinician suspicion for IAI increased, 11.0% with less than 1% suspicion for IAI, 13.5% with 1% to 5% suspicion, 20.5% with 6% to 10% suspicion, 23.2% with 11% to 50% suspicion, and 30.7% with greater than 50% suspicion. The patients in whom the clinicians had a suspicion of IAI of 1% to 5% or 6% to 10% were significantly less likely to undergo a CT scan if a FAST examination was performed: RR, 0.83 (0.67-1.03); RR, 0.81 (0.72-0.91); RR, 0.85 (0.78-0.94); RR, 0.99 (0.94-1.05); and RR, 0.97 (0.91-1.05) for patients with clinician suspicion of IAI of less than 1%, 1% to 5%, 6% to 10%, 11% to 50%, and greater than 50%, respectively.

CONCLUSION

The FAST examination is used in a relatively small percentage of children with BTT. Use increases as clinician suspicion for IAI increases. Patients with a low or moderate clinician suspicion of IAI are less likely to undergo AbCT if they receive a FAST examination. A randomized controlled trial is required to more precisely determine the benefits and drawbacks of the FAST examination in the evaluation of children with BTT.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, II.

Drowning after falling from a medium-height bridge: multiple trauma victims

INTRODUCTION

Drowning following a fall from a bridge can lead to cardiac arrest caused by hypoxia, hypothermia, or severe traumatic injury. Every year patients are brought to our hospital who have nearly drowned in the local river after a jump from a bridge (approximate height 16-22 meters). We report traumatic injuries in patients admitted to our hospital for out-of-hospital cardiac arrest due to drowning.

METHODS

We retrospectively reviewed the charts of all patients admitted to the intensive care units of our hospital for out-of-hospital cardiac arrest due to drowning after a jump from a bridge in the Seine River between 2002 and 2010. All clinical or radiologic evidence of trauma was recorded.

RESULTS

A total of 37 patients where admitted to our hospital for out-of-hospital cardiac arrest due to drowning. Fourteen patients had radiologic examinations. Five of these examinations showed evidence of severe trauma. In one case, clinical examination showed evidence of severe peripheral neurologic trauma. Seven of these patients (19%) were discharged from the hospital alive.

CONCLUSIONS

Patients found nearly drowned in a river spanned by a medium-height bridge should undergo spinal immobilization and complete radiologic examination as soon as possible.

[How should anesthesiologists perform ultrasound examinations? Diagnostic use of ultrasound in emergency and intensive care and medicine]

Ultrasound imaging has attained great significance as a tool for diagnostics in emergency and intensive care medicine. The major advantages of this technique are its instantaneous bedside availability and the possibility to perform repeatable examinations. These advantages are based on recent developments, such as portable ultrasound devices offering excellent imaging quality as well as a quick-start-function. Ultrasound imaging in critically ill patients is frequently performed under pressure of time depending on the current acute physical state. All standard examinations in echocardiography, vascular, abdominal and thoracic ultrasound scanning can be applied in these patients. Based on the clinical scenario the duration of examinations may vary from seconds during cardiopulmonary resuscitations to time-consuming repeated scanning. The transition from basic to subject-specific detailed examinations is flowing and has to be adjusted to local conditions. In the field of emergency and intensive care medicine the technique used is whole-body sonography. The goal is to classify the patient's present physical state and to define a targeted therapeutic approach. The characteristics of whole-body sonography are similar to the field of anesthesiology which is an interdisciplinary one. Currently, these characteristics deserve more attention in training in sonography.

Extended focused assessment with sonography for trauma (EFAST) in the diagnosis of pneumothorax: experience at a community based level I trauma center

INTRODUCTION

Early identification of pneumothorax is crucial to reduce the mortality in critically injured patients. The objective of our study is to investigate the utility of surgeon performed extended focused assessment with sonography for trauma (EFAST) in the diagnosis of pneumothorax.

METHODS

We prospectively analysed 204 trauma patients in our level I trauma center over a period of 12 (06/2007-05/2008) months in whom EFAST was performed. The patients' demographics, type of injury, clinical examination findings (decreased air entry), CXR, EFAST and CT scan findings were entered into the data base. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated.

RESULTS

Of 204 patients (mean age--43.01+/-19.5 years, sex--male 152, female 52) 21 (10.3%) patients had pneumothorax. Of 21 patients who had pneumothorax 12 were due to blunt trauma and 9 were due to penetrating trauma. The diagnosis of pneumothorax in 204 patients demonstrated the following: clinical examination was positive in 17 patients (true positive in 13/21, 62%; 4 were false positive and 8 were false negative), CXR was positive in 16 (true positive in 15/19, 79%; 1 false positive, 4 missed and 2 CXR not performed before chest tube) patients and EFAST was positive in 21 patients (20 were true positive [95.2%], 1 false positive and 1 false negative). In diagnosing pneumothorax EFAST has significantly higher sensitivity compared to the CXR (P=0.02).

CONCLUSIONS

Surgeon performed trauma room extended FAST is simple and has higher sensitivity compared to the chest X-ray and clinical examination in detecting pneumothorax.

Test characteristics of focused assessment of sonography for trauma for clinically significant abdominal free fluid in pediatric blunt abdominal trauma

OBJECTIVES

Focused assessment of sonography in trauma (FAST) has been shown useful to detect clinically significant hemoperitoneum in adults, but not in children. The objectives were to determine test characteristics for clinically important intraperitoneal free fluid (FF) in pediatric blunt abdominal trauma (BAT) using computed tomography (CT) or surgery as criterion reference and, second, to determine the test characteristics of FAST to detect any amount of intraperitoneal FF as detected by CT.

METHODS

This was a prospective observational study of consecutive children (0-17 years) who required trauma team activation for BAT and received either CT or laparotomy between 2004 and 2007. Experienced physicians performed and interpreted FAST. Clinically important FF was defined as moderate or greater amount of intraperitoneal FF per the radiologist CT report or surgery.

RESULTS

The study enrolled 431 patients, excluded 74, and analyzed data on 357. For the first objective, 23 patients had significant hemoperitoneum (22 on CT and one at surgery). Twelve of the 23 had true-positive FAST (sensitivity = 52%; 95% confidence interval [CI] = 31% to 73%). FAST was true negative in 321 of 334 (specificity = 96%; 95% CI = 93% to 98%). Twelve of 25 patients with positive FAST had significant FF on CT (positive predictive value [PPV] = 48%; 95% CI = 28% to 69%). Of 332 patients with negative FAST, 321 had no significant fluid on CT (negative predictive value [NPV] = 97%; 95% CI = 94% to 98%). Positive likelihood ratio (LR) for FF was 13.4 (95% CI = 6.9 to 26.0) while the negative LR was 0.50 (95% CI = 0.32 to 0.76). Accuracy was 93% (333 of 357, 95% CI = 90% to 96%). For the second objective, test characteristics were as follows: sensitivity = 20% (95% CI = 13% to 30%), specificity = 98% (95% CI = 95% to 99%), PPV = 76% (95% CI = 54% to 90%), NPV = 78% (95% CI = 73% to 82%), positive LR = 9.0 (95% CI = 3.7 to 21.8), negative LR = 0.81 (95% CI = 0.7 to 0.9), and accuracy = 78% (277 of 357, 95% CI = 73% to 82%).

CONCLUSION

In this population of children with BAT, FAST has a low sensitivity for clinically important FF but has high specificity. A positive FAST suggests hemoperitoneum and abdominal injury, while a negative FAST aids little in decision-making.

Clinician performed resuscitative ultrasonography for the initial evaluation and resuscitation of trauma

BACKGROUND

Traumatic injury is a leading cause of morbidity and mortality in developed countries worldwide. Recent studies suggest that many deaths are preventable if injuries are recognized and treated in an expeditious manner - the so called 'golden hour' of trauma. Ultrasound revolutionized the care of the trauma patient with the introduction of the FAST (Focused Assessment with Sonography for Trauma) examination; a rapid assessment of the hemodynamically unstable patient to identify the presence of peritoneal and/or pericardial fluid. Since that time the use of ultrasound has expanded to include a rapid assessment of almost every facet of the trauma patient. As a result, ultrasound is not only viewed as a diagnostic test, but actually as an extension of the physical exam.

METHODS

A review of the medical literature was performed and articles pertaining to ultrasound-assisted assessment of the trauma patient were obtained. The literature selected was based on the preference and clinical expertise of authors.

DISCUSSION

In this review we explore the benefits and pitfalls of applying resuscitative ultrasound to every aspect of the initial assessment of the critically injured trauma patient.

The clinical and technical evaluation of a remote telementored telesonography system during the acute resuscitation and transfer of the injured patient

BACKGROUND

Ultrasound (US) has an ever increasing scope in the evaluation of trauma, but relies greatly on operator experience. NASA has refined telesongraphy (TS) protocols for traumatic injury, especially in reference to mentoring inexperienced users. We hypothesized that such TS might benefit remote terrestrial caregivers. We thus explored using real-time US and video communication between a remote (Banff) and central (Calgary) site during acute trauma resuscitations.

METHODS

A existing internet link, allowing bidirectional videoconferencing and unidirectional US transmission was used between the Banff and Calgary ERs. Protocols to direct or observe an extended focused assessment with sonography for trauma (EFAST) were adapted from NASA algorithms. A call rota was established. Technical feasibility was ascertained through review of completed checklists. Involved personnel were interviewed with a semistructured interview.

RESULTS

In addition to three normal volunteers, 20 acute clinical examinations were completed. Technical challenges requiring solution included initiating US; audio and video communications; image freezing; and US transmission delays. FAST exams were completed in all cases and EFASTs in 14. The critical anatomic features of a diagnostic examination were identified in 98% of all FAST exams and a 100% of all EFASTs that were attempted. Enhancement of clinical care included confirmation of five cases of hemoperitoneum and two pneumothoraces (PTXs), as well as educational benefits. Remote personnel were appreciative of the remote direction particularly when instructions were given sequentially in simple, nontechnical language.

CONCLUSIONS

The remote real-time guidance or observation of an EFAST using TS appears feasible. Most technical problems were quickly overcome. Further evaluation of this approach and technology is warranted in more remote settings with less experienced personnel.

Hepatic Trauma

Hepatic injuries are one of the most common abdominal injuries following either blunt or penetrating trauma. CT scanning has revolutionized the treatment algorithm for these patients. The majority of patients are successfully treated with nonoperative management, but surgeons should have a clear understanding of the indications for operative intervention. An array of techniques including operative, interventional, and endoscopic, are often required for management of advanced grade hepatic injuries.

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.

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.

Free fluid in Morison's pouch on bedside ultrasound predicts need for operative intervention in suspected ectopic pregnancy

BACKGROUND

Ectopic pregnancies are frequently present in women who present to the emergency department with pregnancy and abdominal pain or bleeding, a subset of whom may require operative intervention.

OBJECTIVES

To prospectively determine if emergency physician (EP)-performed transabdominal pelvic ultrasonography (US) with determination of free abdominal fluid in the hepatorenal space predicted the need for operative intervention.

METHODS

Patients who were suspected to have an ectopic pregnancy were prospectively enrolled over a ten-month period. An EP-performed bedside transabdominal pelvic US that included a view of the hepatorenal space (Morison's pouch) for free fluid. The EP US was classified as intrauterine pregnancy (IUP) or no definitive IUP, with Morison's pouch classified as positive or negative. The majority of patients had a subsequent transvaginal pelvic US performed by the Department of Radiology. Patients were followed up for radiology results, need for operative intervention, and ultimate outcome of the pregnancy.

RESULTS

There were 242 patients enrolled, with an average time to complete the EP US of 4 minutes and 27 seconds. There were 28 ectopic pregnancies diagnosed (11.6%), of which 18 patients underwent operative intervention. Free fluid in Morison's pouch was identified in ten patients, nine of whom underwent operative intervention, yielding a positive likelihood ratio of 112 (95% confidence interval = 15 to 831) for patients with suspected ectopic pregnancy who required operative intervention.

CONCLUSIONS

Free intraperitoneal fluid found in Morison's pouch in patients with suspected ectopic pregnancy may be rapidly identified at the bedside by EP-performed US and predicts the need for operative intervention.

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.

Battling fire and ice: remote guidance ultrasound to diagnose injury on the International Space Station and the ice rink

BACKGROUND

National Aeronautical and Space and Administration (NASA) researchers have optimized training methods that allow minimally trained, non-physician operators to obtain diagnostic ultrasound (US) images for medical diagnosis including musculoskeletal injury. We hypothesize that these techniques could be expanded to non-expert operators including National Hockey League (NHL) and Olympic athletic trainers to diagnose musculoskeletal injuries in athletes.

METHODS

NHL and Olympic athletic trainers received a brief course on musculoskeletal US. Remote guidance musculoskeletal examinations were conducted by athletic trainers, consisting of hockey groin hernia, knee, ankle, elbow, or shoulder evaluations. US images were transmitted to remote experts for interpretation.

RESULTS

Groin, knee, ankle, elbow, or shoulder images were obtained on 32 athletes; all real-time US video stream and still capture images were considered adequate for diagnostic interpretation.

CONCLUSIONS

This experience suggests that US can be expanded for use in locations without a high level of on-site expertise. A non-physician with minimal training can perform complex, diagnostic-quality examinations when directed by a remote-based expert.

Prehospital ultrasound imaging improves management of abdominal trauma

BACKGROUND

Blunt abdominal trauma with intra-abdominal bleeding is often underdiagnosed or even overlooked at trauma scenes. The purpose of this prospective, multicentre study was to compare the accuracy of physical examination and prehospital focused abdominal sonography for trauma (PFAST) to detect abdominal bleeding.

METHODS

Six rescue centres took part in the study from December 2002 to December 2003, including 230 patients with suspected abdominal injury. The accuracy of physical examination at the scene and PFAST were compared. Later examinations in the emergency department (ultrasonography and/or computed tomography) were used as the reference standard.

RESULTS

The complete protocol and follow-up was obtained in 202 patients. The sensitivity, specificity and accuracy of PFAST were 93 per cent, 99 per cent and 99 per cent, respectively, compared with 93 per cent, 52 per cent and 57 per cent for physical examination at the scene. Scanning with PFAST occurred a mean(s.d.) 35(13) min earlier than ultrasound in the emergency department. Abdominal bleeding was detected in 14 per cent of patients. Using PFAST led to a change in either prehospital therapy or management in 30 per cent of patients, and a change to admitting hospital in 22 per cent.

CONCLUSION

In this study, PFAST was a useful and reliable diagnostic tool when used as part of surgical triage at the trauma scene.

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.