Screening ultrasonography of 2,204 patients with blunt abdominal trauma in the Wenchuan earthquake

Is a Positive Prehospital FAST Associated with Severe Bleeding? A Multicenter Retrospective Study

INTRODUCTION

Severe hemorrhage is the leading cause of early preventable death in severe trauma patients. Delayed diagnosis is a poor prognostic factor, and severe hemorrhage prediction is essential. The aim of our study was to investigate if there was an association between the detection of peritoneal or pleural fluid on prehospital sonography for trauma and posttraumatic severe hemorrhage.

METHODS

We retrospectively studied data from records of thoracic or abdominal trauma patients managed in mobile intensive care units from January 2017 to December 2021 in four centers in France. Severe hemorrhage was defined as a condition necessitating transfusion of at least four packed red blood cells or surgical intervention/radioembolization for hemostasis within the first 24 h. Using a multivariate analysis, we investigated the predictive performance of focused assessment with sonography for trauma (FAST) alone or in combination with the five Red Flags criteria validated by Hamada et al.

RESULTS

Among the 527 patients analyzed, 371 (71%) were men, the mean age was 41 ± 19 years, and the Injury Severity Score was 11 (Interquartile range = [5; 22]). Seventy-three (14%) patients had severe hemorrhage - of whom 28 (38%) had a positive FAST, compared to 61 (13%) without severe hemorrhage (p < 0.01). For severe hemorrhage prediction, FAST had a sensitivity of 38% (95%CI = [27%; 50%]) and a specificity of 87% (95%CI = [83%; 90%]) (AUC = 0.62, 95%CI = [0.57; 0.68]). The comparison of the other outcomes between positive and negative FAST was: hemostatic procedure, 22 (25%) vs 28 (6%), p < 0.01; intensive care unit admission 71 (80%) vs 190 (43%), p < 0.01; mean length of hospital stay 11 [4; 27] vs 4 [0; 14] days, p = 0.02; 30-day mortality 13 (15%) vs 22 (5%), p < 0.01.

CONCLUSION

A positive FAST performed in the prehospital setting is associated with severe hemorrhage and all prognostic criteria we studied.

Traumatic hemorrhage and chain of survival

Trauma is the number one cause of death among Americans between the ages of 1 and 46 years, costing more than $670 billion a year. Following death related to central nervous system injury, hemorrhage accounts for the majority of remaining traumatic fatalities. Among those with severe trauma that reach the hospital alive, many may survive if the hemorrhage and traumatic injuries are diagnosed and adequately treated in a timely fashion. This article aims to review the recent advances in pathophysiology management following a traumatic hemorrhage as well as the role of diagnostic imaging in identifying the source of hemorrhage. The principles of damage control resuscitation and damage control surgery are also discussed. The chain of survival for severe hemorrhage begins with primary prevention; however, once trauma has occurred, prehospital interventions and hospital care with early injury recognition, resuscitation, definitive hemostasis, and achieving endpoints of resuscitation become paramount. An algorithm is proposed for achieving these goals in a timely fashion as the median time from onset of hemorrhagic shock and death is 2 h.

The Utility of the Focused Assessment With Sonography in Trauma Examination in Pediatric Blunt Abdominal Trauma: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the utility of the Point of Care Ultrasound (POCUS) Focused Assessment with Sonography for Trauma (FAST) examination for diagnosis of intra-abdominal injury (IAI) in children presenting with blunt abdominal trauma.

METHODS

We searched medical literature from January 1966 to March 2018 in PubMed, EMBASE, and Web of Science. Prospective studies of POCUS FAST examinations in diagnosing IAI in pediatric trauma were included. Sensitivity, specificity, and likelihood ratios (LR) were calculated using a random-effects model (95% confidence interval). Study quality and bias risk were assessed, and test-treatment threshold estimates were performed.

RESULTS

Eight prospective studies were included encompassing 2135 patients with a weighted prevalence of IAI of 13.5%. Studies had variable quality, with most at risk for partial and differential verification bias. The results from POCUS FAST examinations for IAI showed a pooled sensitivity of 35%, specificity of 96%, LR+ of 10.84, and LR- of 0.64. A positive POCUS FAST posttest probability for IAI (63%) exceeds the upper limit (57%) of our test-treatment threshold model for computed tomography of the abdomen with contrast. A negative POCUS FAST posttest probability for IAI (9%) does not cross the lower limit (0.23%) of our test-treatment threshold model.

CONCLUSIONS

In a hemodynamically stable child presenting with blunt abdominal trauma, a positive POCUS FAST examination result means that IAI is likely, but a negative examination result alone cannot preclude further diagnostic workup for IAI. The need for computed tomography scan may be obviated in a subset of low-risk pediatric blunt abdominal trauma patients presenting with a Glasgow Coma Scale of 14 to 15, a normal abdominal examination result, and a negative POCUS FAST result.

Duodeno-pancreatic and extrahepatic biliary tree trauma: WSES-AAST guidelines

Duodeno-pancreatic and extrahepatic biliary tree injuries are rare in both adult and pediatric trauma patients, and due to their anatomical location, associated injuries are very common. Mortality is primarily related to associated injuries, but morbidity remains high even in isolated injuries. Optimal management of duodeno-bilio-pancreatic injuries is dictated primarily by hemodynamic stability, clinical presentation, and grade of injury. Endoscopic and percutaneous interventions have increased the ability to non-operatively manage these injuries. Late diagnosis and treatment are both associated to increased morbidity and mortality. Sequelae of late presentations of pancreatic injury and complications of severe pancreatic trauma are also increasingly addressed endoscopically and with interventional radiology procedures. However, for moderate and severe extrahepatic biliary and severe duodeno-pancreatic injuries, immediate operative intervention is preferred as associated injuries are frequent and commonly present with hemodynamic instability or peritonitis. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and American Association for the Surgery of Trauma (AAST) duodenal, pancreatic, and extrahepatic biliary tree trauma management guidelines.

Accuracy of Focused Assessment with Sonography for Trauma (FAST) in Disaster Settings: A Meta-Analysis and Systematic Review

Focused assessment with sonography for trauma (FAST) has been incorporated into the initial evaluation of trauma for decades. It is an important screening tool in the detection of intra-abdominal fluid. The objective of this study was to perform a systematic review of the use and accuracy of FAST as an imaging tool for blunt abdominal trauma in disaster/mass casualty settings. A systematic review of literature was conducted using key words and search terms. Two independent reviewers screened abstracts to determine inclusion using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS). For studies passing QUADAS, a meta-analysis was performed calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). FAST results were compared with the gold standard, which was a combination of CT scan results, operative findings, and medical records of the clinical course. Initial database screening resulted in 133 articles, of which 21 were selected for QUADAS evaluation. Five studies passed QUADAS and were selected in the final meta-analysis, with a total of 4263 patients. The sensitivity of FAST was 92.1% (87.8–95.6), specificity 98.7% (96.0–99.9), PPV 90.7% (70.0–98.0), and NPV 98.8% (98.1–99.5) for the detection of intra-abdominal injury. In our meta-analysis, FAST was both sensitive and specific in the evaluation of trauma in the disaster setting.

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.

Clinically Unjustified Diagnostic Imaging - a Worrisome Tendency in Today's Medical Practice

Background

The purpose of the study was to evaluate the percentage of unjustified examinations among all the CT and MRI studies performed by two radiology departments and to determine the types of examinations which are most commonly carried out unnecessarily.

Material/Methods

Three radiologists assessed the justification of CT and MRI examinations performed during a period of 14 days based on the referrals. The radiologists assessed 799 referrals for CT scans (847 examinations of a particular part of the body) and 269 MRI referrals (269 examinations). The criteria for justification were: medical expertise and the guidelines. During the first stage radiologists divided the examinations into 3 groups: justified, unjustified and the examinations of questionable justification. The second step was to determine the reasons why the studies were considered as unjustified or of questionable justification.

Results

73 of 1116 examinations (6.54%) were considered to be unjustified or of a questionable justification. There were 59 CT scans (59/847=6.97%) and 14 MRI studies (14/269=5.20%). The most common reasons to consider them as unjustified or of questionable justification were: inadequate method of diagnostic imaging chosen as a first-line tool and lacking or insufficient clinical details.

Conclusions

In our investigation 6.54% of both CT and MRI examinations were considered as unjustified or of questionable justification, which is lower than described in other studies (from 7% to 26%). The assessment was based only on referrals, therefore a total share of these examinations is likely to be higher.

Transfer of real-time ultrasound video of FAST examinations from a simulated disaster scene via a mobile phone

OBJECTIVE

Disaster management is a complex and difficult undertaking that may involve limited health care resources and evaluation of multiple victims. The objectives of this study were to evaluate the feasibility of real-time ultrasound video transmission from a simulated disaster triage location via commercially available video mobile phones and assess the ability of emergency physicians to accurately interpret the transmitted video of Focused Assessment with Sonography for Trauma (FAST) ultrasound examinations.

METHODS

This was a prospective, observational study that took place at a simulated disaster scene put on for an Advanced Disaster Life Support (ADLS) course. The second component occurred at a Level I academic urban emergency department (ED) with an annual census of 78,000. Nineteen subjects at a simulated disaster scene were scanned using a SonoSite Titan ultrasound system (Bothell, Washington USA). An off-the-shelf, basic, video-capable mobile phone was used to record each ultrasound examination; and then immediately transmit the videos to another mobile phone approximately 170 miles away. The transmitted video was received by three emergency physicians with hospital credentialing in emergency ultrasound. Each FAST examination video was assessed for pathology, such as free fluid. The reviewers graded the image quality and documented the overall confidence level regarding whether or not a complete and adequate examination was visualized. Spearman's rank correlation coefficient was used to examine the agreement between the reviewers and the sonologist who performed the ultrasound examinations.

RESULTS

A total of 19 videos were transmitted. The median time for transmission of a video was 82.5 seconds (95% CI, 67.7 seconds-97.3 seconds). No video failed to transmit correctly on the first attempt. The image quality ratings for the three reviewers were 7.7, 7.5, and 7.4 on a 10-point Likert scale. There was a moderate agreement between the reviewers and sonologist in image quality rating and overall confidence level scores (rho = 0.6).

CONCLUSIONS

Real-time portable ultrasound video transmission via commercially available video mobile phones from a simulated disaster triage location is feasible and emergency physicians were able to accurately interpret video of FAST ultrasound examinations.

Resuscitation in a multiple casualty event

A major weakness in the emergency medical response to multiple casualty events continues to be the resuscitation component, which should consist of the systematic application of basic, advanced, and prolonged life support and definitive care within 24 hours. There have been major advances in emergency medical care over the last decade, including the feasibility of point-of-care ultrasound to aid in rapid assessment of injuries in the field, damage control resuscitation, and resuscitative surgery protocols, delivered by small trauma/resuscitation teams equipped with regional anesthesia capability for rapid deployment. Widespread adoption of these best practices may improve the delivery of resuscitative care in future multiple casualty events.