FAST exam

Ultrasound basic terminology

FAST (focused assessment with sonography in trauma)

Indications

  • Blunt/penetrating trauma to abdomen/chest
  • Trauma in pregnancy (no radiation)
  • Unexplained hypotension

Uses

  • Rapid, portable test to triage trauma patients
  • Looking for fluid in the abdomen/heart/lungs
  • Hemoperitoneum: sens. 76-90%, spec. 95-100%
  • Pericardial effusion/hemothorax: sens. ~100%
  • Pneumothorax: sens. 88%, spec. 99% (vs. CXR sens. 52%)

Limitations

  • Typically does not identify source of bleeding
  • Not great at detecting bowel/mesentery injuries
  • Difficult to assess retroperitoneum
  • Limited by body habitus
  • Use curvilinear probe
View Normal Abnormal

RUQ: liver, kidney - Morisson's pouch

Need to get liver edge for full view.

Extend upwards to look for hemothorax

 FAST RUQ - normal FAST RUQ - abnormal

LUQ: spleen, kidney

Extend upwards to look for hemothorax

   FAST - LUQ abnormal
Pelvis: transverse FAST - pelvis transverse normal  
Pelvis: sagittal   FAST pelvis sagittal abnormal
Subxiphoid - heart, pericardium FAST subxiphoid - normal FAST subxiphoid - abnormal
extended FAST (eFAST)
Thorax - pneumothorax (2-3 views per lung)

FAST thorax - normal

B-mode: comet tail, sliding sign (visceral/parietal pleura slide against each other)

FAST thorax - abnormal

B-mode: no sliding (air from pneumothorax disrupts pleural interface)

M-mode: "sandy beach" (motion of sliding pleura is detected)

M-mode: "barcode"/"stratosphere", (no motion detected)
  Stable Unstable
(+) FAST CT OR
(-) FAST CT Panic
author: admin | last edited: Jan. 8, 2019, 8:09 p.m. | pk: 92