EFAST (Extended Focused Assessment with Sonography for Trauma)
EFAST is an extension of FAST (Focused Assessment with Sonography for Trauma) that adds thoracic views .
PROBE & SETTINGS
- Probe: Curvilinear (3–5 MHz) or phased array
- Depth: 15–20 cm (abdomen), shallow for lung
- Mode: B-mode (main), M-mode (for lung)
1. Pericardial View (Cardiac)
A. Subxiphoid (Subcostal) view
- Probe below xiphisternum → Aim probe toward towards left shoulder(marker right side)
B. Parasternal View (Alternative)
Position-Left parasternal region,3rd–5th intercostal space
Orientation Marker toward:Right shoulder
Looks for:
- Pericardial effusion
- Tamponade physiology
Key signs:
- Anechoic fluid around heart
- RV/RA collapse → tamponade
2. RUQ View (Morrison’s Pouch)
Between liver & right kidney, Most sensitive abdominal view
Right mid-axillary line,Around 8th–11th intercostal space
Looks for:
- Free fluid in:
- Hepatorenal recess (Morrison’s pouch)
- Inferior liver tip
- Right paracolic gutter
Ascites behaves somewhat differently from acute traumatic hemoperitoneum, although both follow gravity.
In a supine patient with ascites The first and most dependent site of fluid accumulation is the pelvis, not Morison’s pouch.
3. LUQ View (Splenorenal)
Between spleen & left kidney
Place probe:
- Posterior axillary line
- Around 6th–9th intercostal space
Looks for:
- Fluid in splenorenal recess
- Around spleen
- Left paracolic gutter
Trickier than RUQ (more posterior)
4. Pelvic View(transverse and longitudinal)
Probe just above pubic symphysis
Suprapubic (full bladder helps)
Looks for:
- Free fluid in:
- Pouch of Douglas (female)
- Rectovesical pouch (male)
5. Lung View – Pneumothorax
Anterior chest (2nd–4th ICS, midclavicular)
Signs:
|
Finding |
Interpretation |
|
Lung sliding |
No pneumothorax |
|
Absent sliding |
Suspicious |
|
Barcode sign (M-mode) |
Pneumothorax |
|
Seashore sign |
Normal lung |
|
Lung point |
Pathognomonic |
6. Lung Base – Hemothorax
Costophrenic angles (with RUQ/LUQ views)
Looks for:
- Anechoic fluid above diaphragm
- “Spine sign” (thoracic vertebrae visible above diaphragm)
INTERPRETATION
🟥 Positive EFAST
- Free fluid OR pneumothorax detected
Management:
- Unstable patient → IMMEDIATE SURGERY
- Laparotomy / thoracotomy
- Stable → CT scan
🟩 Negative EFAST
- No fluid detected BUT: Does NOT rule out injury
- Repeat EFAST (serial exams)
- CT scan if stable
SENSITIVITY & LIMITATIONS
|
Condition |
Sensitivity |
|
Hemoperitoneum |
~85–95% |
|
Cardiac tamponade |
>95% |
|
Pneumothorax |
>90% (better than CXR) |
LIMITATIONS
- Misses:
- Small fluid (<200–300 mL)
- Hollow viscus injury
- Retroperitoneal bleed
- Operator dependent
- Obesity / bowel gas interfere
PITFALLS
- Perinephric fat → mistaken for fluid
- Gastric fluid → false positive LUQ
- Mirror artifacts near diaphragm
- Absent lung sliding ≠ always pneumothorax (e.g., ARDS, apnea)
NOT Designed To Detect
- Solid organ injury
- Bowel injury
- Retroperitoneal bleeding
- Mesenteric injury
- Aortic injury
- Pelvic fracture
- Hollow viscus perforation
Absence of free fluid does not exclude significant intra-abdominal injury.