eFAST Protocol: Examination Points, Detection of Free Fluid and Pneumothorax in Trauma
Purpose and Role in Diagnostics
FAST (focused assessment with sonography for trauma) has become an extension of the physical examination of a trauma patient (Hagen-Ansert, 2023). It is a focused screening examination of the abdomen, pelvis, and pericardium to assess for free or pericardial fluid. In blunt trauma, timely diagnosis of potentially life-threatening bleeding helps determine patient routing — to the operating room, CT, or angiography (Hagen-Ansert, 2023). The extension to eFAST adds the detection of post-traumatic pneumothorax (Kirkpatrick, J Trauma 2004).
Examination Points and Sequence
According to the ACR-AIUM-SPR-SRU Practice Parameter (2023), longitudinal and transverse images are obtained in the following areas to assess for free fluid:
| Zone | Assessment Area |
|---|---|
| Right Upper Quadrant | Perihepatic and hepatorenal space (liver area) |
| Left Upper Quadrant | Perisplenic area (spleen area) |
| Flanks | Bilateral paracolic gutters |
| Pelvis | Pelvic cavity for free fluid assessment |
| Pericardium | Assessment of pericardial effusion |
Detection of Free Fluid in the Abdominal Cavity
The goal of the abdominal part of FAST is to screen the abdominal cavity for the presence of free fluid (AIUM, 2022; ACR-AIUM-SPR-SRU, 2023). Longitudinal and transverse images are obtained in the right upper quadrant through the liver area, in the left upper quadrant through the spleen area, along the bilateral paracolic gutters, and in the pelvic cavity (ACR-AIUM-SPR-SRU, 2023). The assessment for free fluid also includes limited images of the pelvis and both lower quadrants/paracolic gutters (AIUM, 2022).
Pericardium Assessment
FAST includes an examination of the pericardium to detect pericardial fluid (Hagen-Ansert, 2023). In penetrating injuries, potential diagnostic errors of pericardial effusion on traumatic ultrasound should be considered (Blaivas, Acad Emerg Med 2000).
Detection of Pneumothorax (eFAST Extension)
The extended eFAST protocol additionally aims to detect post-traumatic pneumothorax using thoracic sonography (Kirkpatrick, J Trauma 2004). [note: specific sonographic signs and pleural examination points are not detailed in the provided fragments]
Clinical Significance
The presence of intraperitoneal fluid in patients with blunt trauma has clinical significance (Hahn, Am J Emerg Med 2002). Previously, diagnostic peritoneal lavage (DPL) was used to assess the intraperitoneal space and determine indications for laparotomy; today, FAST in the emergency department has become an extension of the physical examination (Hagen-Ansert, 2023).
Frequently asked questions
What zones are mandatory in FAST abdominal examination?
Right upper quadrant (perihepatic and hepatorenal space), left upper quadrant (perisplenic area), bilateral paracolic gutters, and pelvic cavity; longitudinal and transverse images are obtained (ACR-AIUM-SPR-SRU, 2023).
What does eFAST assess besides the abdominal cavity?
In addition to free fluid in the abdominal cavity and pelvis, the pericardium is assessed for pericardial effusion, and the eFAST extension adds the detection of post-traumatic pneumothorax (Kirkpatrick, J Trauma 2004; Hagen-Ansert, 2023).
What is the clinical role of FAST in trauma?
Timely diagnosis of potentially life-threatening bleeding in trauma serves as a decision-making tool for transfer to the operating room, CT, or angiography (Hagen-Ansert, 2023).
Who performs the FAST examination?
The examination is performed in the emergency department by properly trained and accredited personnel (Hagen-Ansert, 2023).
What should be considered when assessing the pericardium in penetrating trauma?
Potential diagnostic errors of pericardial effusion on traumatic ultrasound in penetrating injuries should be considered (Blaivas, Acad Emerg Med 2000).