FAST Scan
FAST Scan
Focused Assessment with Sonography in Trauma
Indications
- Trauma: blunt > penetrating
- Undifferentiated hypotension
- Pregnancy and hypotension/abdominal pain
- Fluid in the torso
- Abdominal distension
Acquisition
The Scans
4 Views
1. Perihepatic (RUQ)
2. Pericardial/Subxiphoid (SUX)
3. Perisplenic (LUQ)
4. Posterior Cul de Sac
Patient supine
Probe
2-5MHz Curvilinear Probe
or Phased Array Probe
1. Perihepatic Window (Right Upper Quadrant View)
The Moves
Move probe to right mid-axillary line between 8th-12th ribs.
Leading edge towards patient's HEAD.
Tip!
In upper quadrant scans, start in the anterior axillary line, keep the probe parallel to the bed, and sweep back.
Recommended depth: ~15 cm
Normal
Pathology
Free fluid in
Morison's Pouch
2. Pericardial Window (Subxiphoid View)
The Moves
Move probe below xiphoid.
Leading edge towards patient's RIGHT SHOULDER.
Recommended depth: 21 cm
Normal
Pathology
Pericardial effusion
Tamponade (effusion +
RV collapse)
3. Perisplenic Window (Left Upper Quadrant View)
The Moves
Move probe to left mid-axillary line between 8th-11th ribs.
Leading edge towards patient's HEAD.
Tip!
Try not to fan anteriorly in LUQ scans, as you will get stomach artifact. LUQ often obtained by getting knuckles on the bed!
Recommended depth: ~15 cm
Normal
Pathology
Free fluid
4. Pelvic Window (Posterior Cul de Sac View)
The Moves
Move probe to pelvis.
Leading edge towards patient's RIGHT (transverse plane).
Tip!
Start low in the pelvis.
Can also point towards patient's HEAD (longitudinal plane).
Recommended depth: 12 cm
Normal
Pathology (free fluid)
Longitudinal
Male longitudinal
Female longitudinal
Male transverse
Transverse
Female transverse
Limitations
False Negatives
- Too little free fluid
- < 500 cc
- Retroperitoneal fluid/injury
- Renal, pancreas
- Not as sensitive for penetrating trauma
- Hollow organ injury
- Limited windows
- Free air in abdomen
- Habitus
False Positives
- Ascites
- Perinephric fat pad
- Pericardial fat
- Seminal vesicles