FAST Scan

FAST Scan

Focused Assessment with Sonography in Trauma

Cardiac Bahner Video
Aorta Slides

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