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

Abstract

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.

Keywords: ABCDE; FAST; blunt abdominal trauma; cardiac tamponade; critical care; eFAST; echocardiography; emergency department; emergency medicine; intra-abdominal fluid; intraperitoneal; management; pleural effusion; pneumothorax; resuscitation; sonography; trauma; ultrasound.

Figure 1

Materials and methods.

Figure 2

By placing the probe in the right anterior axillary position, it is possible to assess the following: a haematic effusion in Morrison’s pouch (A), located between the liver (1) and the kidney (2); or a pleural effusion (B) accumulating in the costodiaphragmatic recess (e.g., haemothorax). By placing the probe along the left posterior axillary line, it is possible to assess the presence of a left-sided haemothorax above the diaphragm in the costophrenic angle, or a haemorrhage between the spleen (3) and the left kidney (4) in the perisplenic region (C). Abdominal fluid accumulates in the Douglas pouch (D) between the uterus (5) and the rectum (7) in women and in the rectovesical space in males (E). Bladder (6). Prostate (8). With the probe placed in the transverse epigastric position, the pericardial effusion appears as a rim of fluid surrounding the ventricles (F). Left ventricle (9), left atrium (10), right atrium (11), right ventricle (12). The heart is seen in the long-axis view. Extended FAST allows the assessment of the presence of a pneumothorax (G) in a trauma patient by placing the probe sagittally in all four quadrants of each hemithorax in the parasternal view. In normal lung parenchyma, respiratory movements cause variations in the reflected echoes. When the lung is fully expanded, the “seashore sign” can be observed in M-mode. A physiological sliding of the lung from left to right can be seen in B-mode images. If the lung is not fully expanded, the “barcode sign” appears. The total reflection of echoes at the pleural line is caused by air between the two pleural layers. Rib (13).