[The value of ultrasound diagnosis in blunt abdominal and thoracic injuries]

Point-of-Care Ultrasound-History, Current and Evolving Clinical Concepts in Emergency Medicine

Point-of-care ultrasound (PoCUS) has become an indispensable standard in emergency medicine. Emergency medicine ultrasound (EMUS) is the application of bedside PoCUS by the attending emergency physician to assist in the diagnosis and management of many time-sensitive health emergencies. In many ways, using PoCUS is not only the mere application of technology, but also a fusion of already existing examiner skills and technology in the context of a patient encounter. EMUS practice can be defined using distinct anatomy-based applications. The type of applications and their complexity usually depend on local needs and resources, and practice patterns can vary significantly among regions, countries, or even continents. A different approach suggests defining EMUS in categories such as resuscitative, diagnostic, procedural guidance, symptom- or sign-based, and therapeutic. Because EMUS is practiced in a constantly evolving emergency medical setting where no two patient encounters are identical, the concept of EMUS should also be practiced in a fluid, constantly adapting manner driven by the physician treating the patient. Many recent advances in ultrasound technology have received little or no attention from the EMUS community, and several important technical advances and research findings have not been translated into routine clinical practice. The authors believe that four main areas have great potential for the future growth and development of EMUS and are worth integrating: 1. In recent years, many articles have been published on novel ultrasound applications. Only a small percentage has found its way into routine use. We will discuss two important examples: trauma ultrasound that goes beyond e-FAST and EMUS lung ultrasound for suspected pulmonary embolism. 2. The more ultrasound equipment becomes financially affordable; the more ultrasound should be incorporated into the physical examination. This merging and possibly even replacement of aspects of the classical physical exam by technology will likely outperform the isolated use of stethoscope, percussion, and auscultation. 3. The knowledge of pathophysiological processes in acute illness and ultrasound findings should be merged in clinical practice. The translation of this knowledge into practical concepts will allow us to better manage many presentations, such as hypotension or the dyspnea of unclear etiology. 4. Technical innovations such as elastography; CEUS; highly sensitive color Doppler such as M-flow, vector flow, or other novel technology; artificial intelligence; cloud-based POCUS functions; and augmented reality devices such as smart glasses should become standard in emergencies over time.

Feasibility of FAST examination performance with ultrasound contrast

The Focused Abdominal Sonography in Trauma (FAST) examination has several limitations, among which is the inability to reliably detect solid organ injury. We sought to evaluate the feasibility of ultrasound contrast use during a FAST examination and its effect on the ability to delineate vasculature in the spleen and liver from hilum to capsule on simulated patients. This prospective observational case control study was conducted at an urban community hospital Emergency Department (ED) that is a level I trauma facility. During a FAST examination, the liver and spleen were scanned in entirety to evaluate contrast opacification of blood vessels and a latent phase highlighting the parenchyma of the liver and spleen. Each physician, hospital credentialed for the use of emergency ultrasound, scanned the liver and spleen both before and after contrast administration. Five milliliters of contrast were mixed with 16 mL of normal saline and then injected 4 mL at a time through an 18-gauge anticubital catheter. All examinations were successfully completed before contrast agent dissipation. The mean time to complete the FAST examination with interrogation of the liver and spleen was 1 min 42 s (range 1 min 22 s to 2 min 5 s). The mean time to initial visualization of contrast was 15 s (range 12 to 18 s). The latent phase of the ultrasound contrast when the liver or spleen began to shimmer, an effect that would outline hematomas not actively bleeding, occurred at a mean time of 54 s (range 45 s to 1 min 9 s). The ultrasound contrast disappeared at a mean of 2 min 52 s (range of 2 min 16 s to 3 min 33 s). In conclusion, ultrasound contrast use is feasible during the FAST examination and allows enhanced evaluation of solid organ parenchyma during evaluation for solid organ injury.

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

BACKGROUND

The focused assessment for the sonographic examination of the trauma patient (FAST) is a rapid diagnostic test that sequentially surveys for hemopericardium and then the right upper quadrant (RUQ), left upper quadrant (LUQ), and pelvis for hemoperitoneum in patients with potential truncal injuries. The sequence of the abdominal part of the examination, however, has yet to be validated. The objectives of this multicenter study were as follows: (1) to determine where hemoperitoneum is most frequently identified on positive FAST examinations; and (2) to determine if a relationship exists between that areas and the organs injured.

METHODS

Ultrasound registries from four Level I trauma centers identified patients who had true-positive FAST examinations. Demographic data, areas positive on the FAST, and organs injured were recorded; injuries were classified as multiple, single solid organ (liver or spleen), isolated hollow viscus, or retroperitoneal. Relationships between positive locations on the FAST examinations and the associations of organs injured to areas positive were assessed using McNamara's chi2 test; a p value < 0.05 was considered statistically significant.

RESULTS

The RUQ was the most common site where hemoperitoneum was detected, and this was statistically significant compared with either the LUQ or the pelvis. Also, statistically significant correlations (p < 0.001) were observed between positive RUQ areas on the FAST and multiple injuries, single solid organ (liver or spleen) injury, and retroperitoneal injuries.

CONCLUSION

Blood is most often found on the FAST in the RUQ area in patients with multiple intraperitoneal injuries or isolated injury to the liver, spleen, or retroperitoneum, but not when there is injury to a hollow viscus.

Surgeon-performed ultrasound: its use in clinical practice

OBJECTIVE

To highlight areas where surgeon-performed ultrasound (US) is an effective diagnostic and therapeutic tool.

SUMMARY BACKGROUND DATA

The success of US in trauma and technologic advances have enhanced the interest and ability of surgeons to perform their own US examinations.

METHODS

General surgeons perform US examinations of the thyroid gland, breast, gastrointestinal tract, peritoneal cavity (laparoscopy), and vascular system. Essentials of these examinations are discussed and a plan for educating surgical residents in US is outlined.

RESULTS

Focused assessment for the sonographic examination of the trauma patient, or FAST, is replacing central venous pressure measurements to detect hemopericardium and diagnostic peritoneal lavage to detect hemoperitoneum. Bedside US can be used to detect a pleural effusion so well in critically ill patients that lateral decubitus x-rays are rarely needed. US-directed biopsy of breast lesions is a common office procedure. Laparoscopic US allows tumor staging without formal celiotomy, and many hepatic and pancreatic surgical procedures include US as an adjunct. Endoscopic and endorectal US have added a new dimension to the assessment of many gastrointestinal lesions. Color flow duplex imaging and endoluminal US have significantly expanded the diagnostic and therapeutic aspects of vascular imaging. The training program developed at Emory University and Grady Memorial Hospital is offered as a model for educating surgical residents in US techniques.

CONCLUSIONS

US is a valuable addition to the general surgeon's diagnostic armamentarium and is rapidly becoming an integral part of the surgeon's clinical practice.

Ultrasonography for the initial evaluation of blunt abdominal trauma: A review of prospective trials

Many trauma centers are considering the addition of diagnostic ultrasonography to their trauma protocols. However, a diagnostic imaging application should not be used in general clinical practice until its efficacy has been demonstrated. A literature search was conducted for prospective trials on the use of ultrasound in evaluation of blunt abdominal trauma. Each study was evaluated with the use of an efficacy assessment model. Within this framework, clinical outcomes were classified according to the following efficacy assessment parameters: technical capacity, diagnostic accuracy, diagnostic effect, therapeutic effect, and patient outcome. This model also provided a systematic process for grading the quality of research methods used to obtain each outcome. Eleven trials were found that fulfilled the study criteria, and all of them concluded that ultrasound was valuable for assessment of blunt intraperitoneal trauma. Frequent methodologic flaws were detected in these studies. None of these trials determined therapeutic effect or patient outcome. The criteria for clinical efficacy were not fulfilled. Additional trials should be conducted before ultrasound is accepted as a standard diagnostic test for the evaluation of blunt abdominal trauma.

Quantitative sensitivity of ultrasound in detecting free intraperitoneal fluid

The minimum volume of intraperitoneal fluid that is detectable in Morison's pouch with ultrasound in the trauma setting is not well defined. To evaluate this question, we used diagnostic peritoneal lavage (DPL) as a model for intraperitoneal hemorrhage and undertook a blinded prospective study of the sensitivity of ultrasound in detecting intraperitoneal fluid. Participants included attending physicians and residents in emergency medicine, radiology, and surgery. During the infusion of the DPL fluid, participants continuously scanned Morison's pouch until they detected fluid. All participants were blinded to the rate of infusion and the volume infused. One hundred patients were entered into the study. The mean volume of fluid detected was 619 mL. Only 10% of participants detected fluid volumes less than 400 mL and the overall sensitivity at one liter was 97%. We conclude that reliable detection of intraperitoneal fluid in Morison's pouch requires a greater volume than has been previously described.

[Rectal endosonography in differential diagnosis of surgical diseases of the pelvis]

Rectal endosonography was performed in 35 patients in whom a pathologic process in the pelvis was suspected. Pathologic findings were shown in various cases: abscess, tumours, ascites. It was shown that rectal endosonography can provide information that is not revealed by such established examinations as abdominal sonography and computed tomography. We recommend that the indications for transrectal endosonography can be extended beyond the established use in rectal tumours and diseases of the pelvic floor. Further systematic examinations are required.

Emergency department ultrasound in the evaluation of blunt abdominal trauma

The main objective of this study was to compare bedside sonographic detection of hemoperitoneum with diagnostic peritoneal lavage/laparotomy in the patient with blunt abdominal trauma. A retrospective review was conducted of all blunt trauma patients that underwent emergency department (bedside) sonography to rule out intraperitoneal hemorrhage at a level I trauma center in 1991 to 1992. Patients were included in the study population only if: (1) the results of the ultrasound examination were interpreted before any other diagnostic studies, and (2) a diagnostic peritoneal lavage (DPL) or laparotomy was performed. The ultrasound examination consisted of a single right inter/subcostal longitudinal view with the patient in the trendelenburg position performed by the emergency physician or surgeon. A real-time sector scanner with a 3.5 MHz probe was used. The presence of an anechoic (black) stripe between the liver and the right kidney (Morrison's pouch) was interpreted as a positive study, and the absence of this finding was interpreted as a negative study. A positive DPL was defined as > or = 10 mL of gross blood or a blood cell count > or = 100,000/mm3 in the returned lavage fluid, and a positive laparotomy as > or = 100 mL of intraperitoneal blood. Forty-four patients met the inclusion criteria for the study. Eleven patients (24%) in this population had either a positive DPL or laparotomy. The sensitivity, specificity, and accuracy of bedside sonography in identifying intraperitoneal hemorrhage was 81.8%, 93.9%, and 90.9%, respectively. The ultrasound study provided an answer in less than 1 minute in most patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The place of ultrasonographic examination in the initial evaluation of children sustaining blunt abdominal trauma

Physical examination is stated to be inaccurate in detecting organ injury after blunt abdominal trauma (BAT) in children and the use of diagnostic peritoneal lavage (DPL) and computed tomography (CT) are suggested. However, assessments for the need of such diagnostic aids are quite subjective. The records of 109 patients initially evaluated by ultrasonography (US) for BAT were reviewed to determine whether an easily performed, quick method such as US could be used for selection. US showed free intraperitoneal fluid (FIF) in 30 patients (27.5%) and retroperitoneal injury in 5 patients (4.5%). Of the 30 patients with FIF, 23 patients (76.7%) were treated conservatively but 7 (23.3%) required laparotomy. The correlation between the amount of FIF and the requirement for operative treatment was statistically significant (P < .01). Of the 74 patients (68%) without FIF, clinical outcome was uneventful in 72 (97.3%) while 2 patients (2.7%) required laparotomy for peritonitis and ileal perforations were encountered. The present study has showed that US is inaccurate in detecting solid intraabdominal injuries; however, it is reliable in detecting FIF produced as a result of intraabdominal organ injuries and retroperitoneal organ injuries. We suggest the use of US as the objective initial evaluation method of choice on a routine basis.

[Postoperative hemorrhage]

Postoperative hemorrhage is the second most frequent indication for early relaparotomy. The incidence depends on the level of care in a given hospital. It is highest, therefore, in institutions delivering maximal care with many trauma cases. We performed 3443 laparotomies from January 1988 to March 1991. 214 (5.9%) patients had to be reoperated, 48 of them because of postoperative bleeding. This amounts to 1.3% of the total number of laparotomies. Bleeding was identified through drains, ultrasonography or endoscopy, ultrasonography having the highest sensitivity and specificity. Total mortality was 30%. Analysis of the literature shows that mortality is lowest when relaparotomies are performed on 3%-6% of patients.