Association Between a Positive ED FAST Examination and Therapeutic Laparotomy in Normotensive Blunt Trauma Patients

Resuscitative Ultrasound and Protocols

The management of patients in shock or arrest is a critical aspect of emergency medicine and critical care. Rapid and accurate assessment is paramount in determining the underlying causes and initiating timely interventions. This article provides a summary of essential ultrasound protocols for the critically ill patient including the extended focused assessment with sonography for trauma (EFAST), rapid ultrasound for shock and hypotension (RUSH), and sonography in hypotension and cardiac arrest in the emergency department (SHoC-ED).

The Lipliner Sign: Potential Cause of a False Positive Focused Assessment with Sonography in Trauma (FAST) Examination

BACKGROUND

The focused assessment with sonography in trauma (FAST) examination plays an essential role in diagnosing hemoperitoneum in trauma patients to guide prompt operative management. The FAST examination is highly specific for hemoperitoneum in trauma patients, and has been adopted in nontrauma patients to identify intraperitoneal fluid as a cause of abdominal pain or distension. However, causes of false positive FAST examinations have been described and require prompt recognition to avoid diagnostic uncertainty and inappropriate procedures. Most causes of false positive FAST examinations are due to anatomic mimics such as perinephric fat or seminal vesicles, however, modern ultrasound machines use a variety of postprocessing image enhancement techniques that can also lead to novel false positive artifacts.

CASE REPORT

We report cases where experienced clinicians incorrectly interpreted ultrasound findings caused by a novel mimic of hemoperitoneum: the "lipliner sign." It appears most prominently at the edges of solid organs (such as the liver and the spleen), which is the same location most likely to show free fluid in FAST examination in trauma patients. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Clinicians who take care of trauma patients must be familiar with causes of false positive FAST examinations that could lead to a misdiagnosis of hemoperitoneum.

Prehospital Extended FAST Exams Improve Clinical Decision Making by Helicopter EMS Crews: A Retrospective Case Series

Point of Care Ultrasound (POCUS) has seen increasing use in the prehospital environment over the last decade, primarily with the extended focused assessment with sonography in trauma (eFAST) exam. Previous studies have shown prehospital eFAST exams are feasible in the helicopter transport environment but have yet to demonstrate effects on clinical care. This retrospective case series identified 655 patients with blunt thoraco-abdominal trauma or concern for pneumothorax due to penetrating injury transported by a single helicopter EMS (HEMS) program over a two-year period after introducing POCUS. Of those patients, 258 received prehospital ultrasound which was reported to change clinical care in seven cases (2.7%, 95%-CI [1.1-5.5]). This was primarily through preventing unnecessary needle thoracostomy and initiating blood transfusion for treatment of hemorrhagic shock in cases where the degree of shock was unclear due to inconsistent vital signs. This study highlights the improvements in clinical care that may result from the introduction of eFAST exams in the prehospital environment.

Automated detection and localization of pericardial effusion from point-of-care cardiac ultrasound examination

Focused Assessment with Sonography in Trauma (FAST) exam is the standard of care for pericardial and abdominal free fluid detection in emergency medicine. Despite its life saving potential, FAST is underutilized due to requiring clinicians with appropriate training and practice. To aid ultrasound interpretation, the role of artificial intelligence has been studied, while leaving room for improvement in localization information and computation time. The purpose of this study was to develop and test a deep learning approach to rapidly and accurately identify both the presence and location of pericardial effusion on point-of-care ultrasound (POCUS) exams. Each cardiac POCUS exam is analyzed image-by-image via the state-of-the-art YoloV3 algorithm and pericardial effusion presence is determined from the most confident detection. We evaluate our approach over a dataset of POCUS exams (cardiac component of FAST and ultrasound), comprising 37 cases with pericardial effusion and 39 negative controls. Our algorithm attains 92% specificity and 89% sensitivity in pericardial effusion identification, outperforming existing deep learning approaches, and localizes pericardial effusion by 51% Intersection Over Union with ground-truth annotations. Moreover, image processing demonstrates only 57 ms latency. Experimental results demonstrate the feasibility of rapid and accurate pericardial effusion detection from POCUS exams for physician overread.

POCUS, how can we include the brain? An overview

Point-of-care ultrasound (POCUS) is an essential tool to assess and manage different pathologies in the intensive care unit, and many protocols have been proposed for its application in critical care literature. However, the brain has been overlooked in these protocols.

Brain ultrasonography (BU) is easily available, and it allows a goal-directed approach thanks to its repeatability and immediate interpretation and provides a quick management and real time assessment of patients’ conditions. Based on recent studies, the increasing interest from intensivists, and the undeniable benefits of ultrasound, the main goal of this overview is to describe the main evidence and progresses in the incorporation of BU into the POCUS approach in the daily practice, and thus becoming POCUS-BU. This integration would allow a noninvasive global assessment to entail an integrated analysis of the critical care patients.

Application of Focused Assessment with Sonography for Trauma in the Intensive Care Unit

The Extended-Focused Assessment with Sonography for Trauma (E-FAST) allows clinicians to rapidly diagnose traumatic thoracoabdominal injuries at the bedside without ionizing radiation. It has high specificity and is extremely useful as an initial test to rule in dangerous diagnoses such as hemoperitoneum, pericardial effusion, hemothorax, and pneumothorax. Its moderate sensitivity means that it should not be used alone as a tool to rule out dangerous thoracoabdominal injuries. In patients with a concerning mechanism or presentation, additional imaging should be obtained despite a negative FAST examination.

An Extra Set of Intelligent Eyes: Application of Artificial Intelligence in Imaging of Abdominopelvic Pathologies in Emergency Radiology

Imaging in the emergent setting carries high stakes. With increased demand for dedicated on-site service, emergency radiologists face increasingly large image volumes that require rapid turnaround times. However, novel artificial intelligence (AI) algorithms may assist trauma and emergency radiologists with efficient and accurate medical image analysis, providing an opportunity to augment human decision making, including outcome prediction and treatment planning. While traditional radiology practice involves visual assessment of medical images for detection and characterization of pathologies, AI algorithms can automatically identify subtle disease states and provide quantitative characterization of disease severity based on morphologic image details, such as geometry and fluid flow. Taken together, the benefits provided by implementing AI in radiology have the potential to improve workflow efficiency, engender faster turnaround results for complex cases, and reduce heavy workloads. Although analysis of AI applications within abdominopelvic imaging has primarily focused on oncologic detection, localization, and treatment response, several promising algorithms have been developed for use in the emergency setting. This article aims to establish a general understanding of the AI algorithms used in emergent image-based tasks and to discuss the challenges associated with the implementation of AI into the clinical workflow.

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.

Diagnostic accuracy of pubic symphysis ultrasound in the detection of unstable pelvis in polytrauma patients during e-FAST: the value of FAST-PLUS protocol. A preliminary experience

BACKGROUND

Extended focused abdominal sonography for trauma (e-FAST) is part of the primary survey in patients with high-energy trauma. However, it does not identify patients with retroperitoneal haemorrhage associated with significant pelvic trauma. A traumatic diastasis of pubic symphysis, as well as an 'open book' (OB) pelvic injury, is a diagnostic clue to recognize unstable pelvis with higher risk of bleeding. FAST-PLUS (FAST-PL pleural -US ultrasound of symphysis) protocol is an addendum to the e-FAST, which takes into account the study of the pubic symphysis in a single transverse scan after the traditional focused evaluation of the abdomen and thorax.

OBJECTIVES

The aim of this study is to determine the value of FAST-PLUS protocol in the evaluation of pubic symphysis injuries and the identification of 'open book' (OB) unstable pelvic fractures.

METHODS

Between January 2018 and December 2019, we retrospectively reviewed 67 polytraumatised patients with clinical suspicion of pelvic instability and with known anteroposterior pelvis compression injuries who underwent e-FAST with an additional transverse scan of the pubic symphysis, named the FAST-PLUS protocol and computed tomography (CT) exam in order to assess the correlation between them in defining the presence or absence of pubic symphyseal widening (SW). A cutoff value of 2.5 cm in transverse diameter was used to diagnose OB unstable pelvic injury. The results were analysed using Cohen's test, which uses the Kappa value as the reference index.

RESULTS

The analysis carried out to assess the degree of agreement between FAST-PLUS and CT showed 5/67 patients (7.5%) with a critical pubic SW (> 2.5 cm transverse diameter) suggestive of unstable OB pelvic injury and 62/67 (92,5%) without any signs of SW at FAST-PLUS. At CT, findings of unstable OB pelvic fracture were confirmed in all patients with positive results at FAST-PLUS. Similarly, all patients with negative results for critical pubic SW (< 2.5 cm in transverse diameter) at FAST-PLUS were found to be negative at CT exam. The level of correlation between the two methods was high (Kappa value = 1) CONCLUSION: The FAST-PLUS protocol shows a high correlation with CT exam, which is the gold standard for the detection of unstable pubic SW, as well as OB pelvic injury, in polytraumatised patients. Inclusion of FAST-PLUS in patient management in the shock room may lead to a quicker identification of patients with unstable pelvis and to faster therapeutic work-up.

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.

Point-of-care ultrasonography for diagnosing thoracoabdominal injuries in patients with blunt trauma

BACKGROUND

Point-of-care sonography (POCS) has emerged as the screening modality of choice for suspected body trauma in many emergency departments worldwide. Its best known application is FAST (focused abdominal sonography for trauma). The technology is almost ubiquitously available, can be performed during resuscitation, and does not expose patients or staff to radiation. While many authors have stressed the high specificity of POCS, its sensitivity varied markedly across studies. This review aimed to compile the current best evidence about the diagnostic accuracy of POCS imaging protocols in the setting of blunt thoracoabdominal trauma.

OBJECTIVES

To determine the diagnostic accuracy of POCS for detecting and excluding free fluid, organ injuries, vascular lesions, and other injuries (e.g. pneumothorax) compared to a diagnostic reference standard (i.e. computed tomography (CT), magnetic resonance imaging (MRI), thoracoscopy or thoracotomy, laparoscopy or laparotomy, autopsy, or any combination of these) in patients with blunt trauma.

SEARCH METHODS

We searched Ovid MEDLINE (1946 to July 2017) and Ovid Embase (1974 to July 2017), as well as PubMed (1947 to July 2017), employing a prospectively defined literature and data retrieval strategy. We also screened the Cochrane Library, Google Scholar, and BIOSIS for potentially relevant citations, and scanned the reference lists of full-text papers for articles missed by the electronic search. We performed a top-up search on 6 December 2018, and identified eight new studies which may be incorporated into the first update of this review.

SELECTION CRITERIA

We assessed studies for eligibility using predefined inclusion and exclusion criteria. We included either prospective or retrospective diagnostic cohort studies that enrolled patients of any age and gender who sustained any type of blunt injury in a civilian scenario. Eligible studies had to provide sufficient information to construct a 2 x 2 table of diagnostic accuracy to allow for calculating sensitivity, specificity, and other indices of diagnostic test accuracy.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles, abstracts, and full texts of reports using a prespecified data extraction form. Methodological quality of individual studies was rated by the QUADAS-2 instrument (the revised and updated version of the original Quality Assessment of Diagnostic Accuracy Studies list of items). We calculated sensitivity and specificity with 95% confidence intervals (CI), tabulated the pairs of sensitivity and specificity with CI, and depicted these estimates by coupled forest plots using Review Manager 5 (RevMan 5). For pooling summary estimates of sensitivity and specificity, and investigating heterogeneity across studies, we fitted a bivariate model using Stata 14.0.

MAIN RESULTS

We included 34 studies with 8635 participants in this review. Summary estimates of sensitivity and specificity were 0.74 (95% CI 0.65 to 0.81) and 0.96 (95% CI 0.94 to 0.98). Pooled positive and negative likelihood ratios were estimated at 18.5 (95% CI 10.8 to 40.5) and 0.27 (95% CI 0.19 to 0.37), respectively. There was substantial heterogeneity across studies, and the reported accuracy of POCS strongly depended on the population and affected body area. In children, pooled sensitivity of POCS was 0.63 (95% CI 0.46 to 0.77), as compared to 0.78 (95% CI 0.69 to 0.84) in an adult or mixed population. Associated specificity in children was 0.91 (95% CI 0.81 to 0.96) and in an adult or mixed population 0.97 (95% CI 0.96 to 0.99). For abdominal trauma, POCS had a sensitivity of 0.68 (95% CI 0.59 to 0.75) and a specificity of 0.95 (95% CI 0.92 to 0.97). For chest injuries, sensitivity and specificity were calculated at 0.96 (95% CI 0.88 to 0.99) and 0.99 (95% CI 0.97 to 1.00). If we consider the results of all 34 included studies in a virtual population of 1000 patients, based on the observed median prevalence (pretest probability) of thoracoabdominal trauma of 28%, POCS would miss 73 patients with injuries and falsely suggest the presence of injuries in another 29 patients. Furthermore, in a virtual population of 1000 children, based on the observed median prevalence (pretest probability) of thoracoabdominal trauma of 31%, POCS would miss 118 children with injuries and falsely suggest the presence of injuries in another 62 children.

AUTHORS' CONCLUSIONS

In patients with suspected blunt thoracoabdominal trauma, positive POCS findings are helpful for guiding treatment decisions. However, with regard to abdominal trauma, a negative POCS exam does not rule out injuries and must be verified by a reference test such as CT. This is of particular importance in paediatric trauma, where the sensitivity of POCS is poor. Based on a small number of studies in a mixed population, POCS may have a higher sensitivity in chest injuries. This warrants larger, confirmatory trials to affirm the accuracy of POCS for diagnosing thoracic trauma.

Point-of-Care Ultrasound in Established Settings

The original and most widely accepted applications for point-of-care ultrasound (POCUS) are in the settings of trauma, shock, and bedside procedures. Trauma was the original setting for the introduction of POCUS and has been standardized under the four-plus view examination called the Focused Assessment with Sonography in Trauma (FAST). This examination was found to be especially practice changing for achieving rapid diagnoses in critically ill patients who are too unstable for the delays and transportation inherent in more advanced imaging with computed tomography. This application was broadened from the critically ill trauma patient to any critically ill patient, particularly the patient in undifferentiated shock. Although the Focused Assessment with Sonography in Trauma examination originally focused on sources of hemorrhage causing hypovolemic shock, POCUS also can quickly differentiate cardiogenic, obstructive, and distributive shock and help identify the more specific etiology such as massive pulmonary emboli, pericardial tamponade, and pneumothoraces. By expediting diagnosis, POCUS facilitates faster definitive treatment of life-threatening conditions. In pursuing treatment, US continues to serve a role in the form of visually guiding many procedures that were previously done blindly. US guidance of procedures has improved the safety of central line insertion, thoracentesis, and paracentesis, and has an emerging role in lumbar puncture. Experience in bedside US is becoming a vital tool in the clinician's bedside assessment and management, filling a void between the stethoscope and the more advanced studies and interventions available through radiology. Understanding the strengths and limitations of US enables clinicians to identify the appropriate situations in which they can apply this tool confidently.

Focused assessment with sonography for trauma: current perspectives

Focused assessment with sonography for trauma (FAST) is a part of resuscitation of trauma patients recommended by international panel consensus. The purpose of FAST is to identify free fluid, which necessarily means blood in acute trauma patients. In this article, the authors focused on various aspects of FAST in the emergency department, prehospital care, pediatric setting, training and general pearls/pitfalls. Detailed techniques and interpretation of FAST are beyond the scope of this article.

Should we perform a FAST exam in haemodynamically stable patients presenting after blunt abdominal injury: a retrospective cohort study

Background

Focussed Assessment with Sonography for Trauma (FAST) is a bedside ultrasonography technique used to detect free intraperitoneal fluid in patients presenting with blunt abdominal trauma (BAT) in the emergency department.

Methods

In this retrospective cohort study we investigated the potential of FAST as a risk stratification instrument in haemodynamically (HD) stable patients presenting after BAT by establishing the association between the FAST exam result and final outcome. An adverse outcome was defined in this context as the need for either a laparoscopy/laparotomy or an angiographic embolization or death due to abdominal injuries).

Results

A total of 421 patients with BAT were included, of which nine had an adverse outcome (2%). FAST was negative in 407 patients. Six of them turned out to have free intraperitoneal fluid (sensitivity 67 [41–86]%). FAST was positive in 14 patients, 12 of whom had free intraperitoneal fluid (specificity 99 [98–100]%). A positive FAST (positive likelihood ratio 34.3 [15.1–78.5]) was stronger associated with an adverse outcome than Injury Severity Score (ISS) or any individual clinical- or biochemical variables measured at presentation in the ED.

Discussion

The FAST exam can provide valuable prognostic information at minimal expenses during the early stages of resuscitation in haemodynamically stable patients presenting with BAT.

Conclusions

FAST exam should not be omitted in patients with BAT.

Electronic supplementary material

The online version of this article (doi:10.1186/s13049-016-0342-0) contains supplementary material, which is available to authorized users.

Image Segmentation and Machine Learning for Detection of Abdominal Free Fluid in Focused Assessment With Sonography for Trauma Examinations: A Pilot Study

The objective of this pilot study was to test the feasibility of automating the detection of abdominal free fluid in focused assessment with sonography for trauma (FAST) examinations. Perihepatic views from 10 FAST examinations with positive results and 10 FAST examinations with negative results were used. The sensitivity and specificity compared to manual classification by trained physicians was evaluated. The sensitivity and specificity (95% confidence interval) were 100% (69.2%-100%) and 90.0% (55.5%-99.8%), respectively. These findings suggest that computerized detection of free fluid on abdominal ultrasound images may be sensitive and specific enough to aid clinicians in their interpretation of a FAST examination.

Correlation Between Intra-Abdominal Free Fluid and Solid Organ Injury in Blunt Abdominal Trauma

Background:

In previous studies, the diagnostic value of Focused Assessment with Sonography for Trauma (FAST) has been evaluated but few studies have been performed on the relationship between the amount of free intra-abdominal fluid and organ injury in blunt abdominal trauma. To select patients with a higher probability of intra-abdominal injuries, several scoring systems have been proposed based on the results of FAST.

Objectives:

The aim of this study was to determine the prognostic value of FAST according to the Huang scoring system and to propose a cut-off point for predicting the presence of intra-abdominal injuries on the Computed Tomography (CT) scan. The correlation between age and Glasgow Coma Scale (GCS) and the presence of intra-abdominal injuries on the CT scan was also assessed.

Patients and Methods:

This study was performed on 200 patients with severe blunt abdominal trauma who had stable vital signs. For all patients, FAST-ultrasound was performed by a radiologist and the free fluid score in the abdomen was calculated according to the Huang score. Immediately, an intravenous contrast-enhanced abdominal CT scan was performed in all patients and abdominal solid organ injuries were assessed. Results were analyzed using Kruskal-Wallis test, Mann-Whitney test and ROC curves. The correlation between age and GCS and the presence of intra-abdominal injuries on CT-scan was also evaluated.

Results:

The mean age of the patients was 29.6 ± 18.3 years and FAST was positive in 67% of the subjects. A significant correlation was seen between the FAST score and the presence of organ injury on CT scan (P < 0.001). Considering the cut-off point of 3 for the free fluid score (with a range of 0-8), sensitivity, specificity, positive predictive value and negative predictive value were calculated to be 0.83, 0.98, 0.93, and 0.95, respectively. Age and GCS showed no significant correlation with intra-abdominal injuries.

Conclusions:

It seems that FAST examination for intra-abdominal fluid in blunt trauma patients can predict intra-abdominal injuries with very high sensitivity and specificity. Using the scoring system can more accurately determine the probability of the presence of abdominal injuries with a cut-off point of three.

Prehospital Evaluation of Effusion, Pneumothorax, and Standstill (PEEPS): Point-of-care Ultrasound in Emergency Medical Services

Introduction

In the United States, there are limited studies regarding use of prehospital ultrasound (US) by emergency medical service (EMS) providers. Field diagnosis of life-threatening conditions using US could be of great utility. This study assesses the ability of EMS providers and students to accurately interpret heart and lung US images.

Methods

We tested certified emergency medical technicians (EMT-B) and paramedics (EMT-P) as well as EMT-B and EMT-P students enrolled in prehospital training programs within two California counties. Participants completed a pre-test of sonographic imaging of normal findings and three pathologic findings: pericardial effusion, pneumothorax, and cardiac standstill. A focused one-hour lecture on emergency US imaging followed. Post-tests were given to all EMS providers immediately following the lecture and to a subgroup one week later.

Results

We enrolled 57 prehospital providers (19 EMT-B students, 16 EMT-P students, 18 certified EMT-B, and 4 certified EMT-P). The mean pre-test score was 65.2%±12.7% with mean immediate post-test score of 91.1%±7.9% (95% CI [22%–30%], p<0.001). Scores significantly improved for all three pathologic findings. Nineteen subjects took the one-week post-test. Their mean score remained significantly higher: pre-test 65.8%±10.7%; immediate post-test 90.5%±7.0% (95% CI [19%–31%], p<0.001), one-week post-test 93.1%±8.3% (95% CI [21%–34%], p<0.001).

Conclusion

Using a small sample of EMS providers and students, this study shows the potential feasibility for educating prehospital providers to accurately identify images of pericardial effusion, pneumothorax, and cardiac standstill after a focused lecture.

The use of FAST scan by paramedics in mass-casualty incidents: a simulation study

INTRODUCTION

The Focused Abdominal Sonography in Trauma (FAST) scan is used to detect free fluid in the peritoneal cavity, or pericardium, to quickly assess for injuries needing immediate surgical intervention. Mass-casualty incidents (MCIs) are settings where paramedics must make triage decisions in minutes. The Simple Triage and Rapid Transport (START) system is used to prioritize transport. The FAST scan can be added to the triage of critical patients, and may aid in triage.

METHODS

This was a single-blinded, randomized control trial. Ten paramedics with field experience were trained with an ultrasound machine in the performance of the FAST scan. Two weeks were allowed to pass before testing to simulate the time between training of standard procedures and their implementation. On test day, five peritoneal dialysis patients with instilled dialysis fluid and five matched control patients were placed in a room in a random order where the paramedics performed FAST scans on each patient. The paramedics were assessed by declaring positive or negative for each evaluation, as well as being timed for the total exercise.

RESULTS

Of the ninety tests (one paramedic dropped out due to family emergency), the paramedics had a mean accuracy of 60% and median of 62% (range 40%-80%). There was a statistically significant higher false-positive rate of 59% than false-negative rate of 41% (P < .01). Sensitivity was 67% with a specificity of 56%. Average time taken was 1,218 seconds (121.8 seconds per patient) with a range of 735-1,701 seconds and a median of 1,108 seconds.

CONCLUSION

In this simulation study, paramedics had difficulty performing FAST scans with a high degree of accuracy. However, they were more apt to call a patient positive, limiting the likelihood for false-negative triage.

Accuracy of FAST scan in blunt abdominal trauma in a major London trauma centre

INTRODUCTION

Blunt abdominal trauma (BAT) is a leading cause of morbidity and mortality. Rapid diagnosis and treatment with the Advanced Trauma Life Support guidelines are vital, leading to the development of Focused Assessment with Sonography in Trauma (FAST).

METHODS

A retrospective study carried out from January 2007-2008 on all patients who presented with BAT and underwent FAST scan. All patients subsequently had a CT scan within 2 h of admission or a laparotomy within two days. The presence of intra-peritoneal free fluid was interpreted as positive.

RESULTS

100 patients with BAT presented; 71 had complete data. The accuracy of FAST in BAT was 59.2%; in these 31 (43.7%) were confirmed by CT and 11 (15%) by laparotomy. There were 29 (40.8%) inaccurate FAST scans, all confirmed by CT. FAST had a specificity of 94.7% (95% CI: 0.75-0.99) and sensitivity of 46.2% (95% CI: 0.33-0.60). Positive Predictive Value of 0.96 (0.81-0.99) and Negative Predictive Value of 0.39 (0.26-0.54). Fisher's exact test shows positive FAST is significantly associated with Intra-abdominal pathology (p=0.001). Cohen's chance corrected agreement was 0.3. 21 out of 28 who underwent laparotomies had positive FAST results indicating accuracy of 75% (95% CI: 57%-87%).

CONCLUSION

Patients with false negative scans, requiring therapeutic laparotomy is concerning. In unstable patients FAST may help in triaging and identifying those requiring laparotomy. Negative FAST scans do not exclude abdominal injury. Further randomised control trials are recommended if the role of FAST is to be better understood.

Has the Pendulum Swung Too Far? The Impact of Missed Abdominal Injuries in the Era of Nonoperative Management

Nonoperative management for traumatic injuries has significantly influenced trauma care during the last decade. We undertook this study to assess the impact of nontherapeutic laparotomies for suspected abdominal injuries compared with delayed laparotomies for questionable abdominal injuries for patients with abdominal trauma. The records of patients admitted to the trauma service between 2002 and 2007 who underwent laparotomies deemed nontherapeutic or delayed were retrospectively reviewed. Demographics, severity of injury, management scheme, and outcome data were analyzed. Sixteen patients underwent delayed laparotomies, whereas 26 patients incurred nontherapeutic laparotomies. Injury severity scores, Glasgow coma scale scores, abdominal abbreviated injury scale score (AIS), and age were similar for both populations. Delayed laparotomies occurred an average of 7 ± 9 days postinjury. Intensive care unit length of stay (26 ± 24 vs 10 ± 6 days), hospital length of stay (40 ± 37 vs 11 ± 10 days), ventilator days (31 ± 29 vs 11 ± 10), and number of abdominal operative procedures (1.9 ± 1.5 vs 1 ± 0) were significantly higher in the delayed laparotomies group versus the nontherapeutic laparotomies group, respectively. Delayed diagnosis of intra-abdominal injuries yielded a significantly increased morbidity and mortality. During the evolving era of technological imaging for traumatic injuries, we must not allow the nonoperative pendulum to swing too far.

Hemorrhage is More Prevalent than Brain Injury in Early Trauma Deaths: The Golden Six Hours

INTRODUCTION

Under the trimodal distribution, most trauma deaths occur within the first hour. Determination of cause of death without autopsy review is inaccurate. The goal of this study is to determine cause of death, in hourly intervals, in trauma patients who died in the first 24 h, as determined by autopsy.

MATERIALS AND METHODS

Trauma deaths that occurred within 24 h at a Level I trauma center were reviewed over a six-year period ending December 2005. Timing of death was separated into 0-1, 1-3, 3-6, 6-12 and 12-24 h intervals. Cause of death was determined by clinical course and AIS scores, and was confirmed by autopsy results.

RESULTS

Overall, 9,388 trauma patients were admitted, of which 185 deaths occurred within 24 h, with 167 available autopsies. Blunt and penetrating were the injury mechanisms in 122 (73%) and 45 (27%) patients, respectively. Of 167 deaths, 73 (43.7%) occurred within the first hour. Brain injury, when compared to other body areas, was the most likely cause of death in all hourly intervals, but hemorrhage was as or more important than brain injury as the cause of death during the first 3 h and up to 6 h. No deaths were attributable to hemorrhage after 12 h.

CONCLUSIONS

The temporal distribution of the cause of death varies in the first 24 h after admission. Hemorrhage should not be overlooked as the cause of death, even after survival beyond 1 h. Understanding the temporal relationship of causes of early death can aid in the targeting of management and surgical training to optimize patient outcome.