FAST exam: Difference between revisions

(Text replacement - " w/ " to " with ")
(update)
Line 1: Line 1:
==Indication==
==Background==
*Prioritize: Do primary survery first ABC"U"D
*Prioritize: Do primary survey of ATLS first ABCDE
*If blunt trauma start with noncardiac views first
*FAST exam follows ABCDE to assess “C” looking for free fluid
*In penetrating start with cardiac views first - r/o tamponade
*Sensitivity of 42% and specificity of ≥98%<ref>Natarajan B, Gupta PK, Cemaj S, et al. FAST scan: Is it worth doing in hemodynamically stable blunt trauma patients? Surgery. 2010;148(4):695-700. </ref><ref>Miller MT, Pasquale MD, Bromberg WJ, et al. Not so FAST. J Trauma. 2003; 54(1):52-59.</ref>
*As little as 100ml of free fluid can be seen<ref>Goldberg GG. Evaluation of ascites by ultrasound. Radiology. 1970; 96(15):217–221.</ref><ref>Von Kuenssberg Jehle D, Stiller G, Wagner D. Sensitivity in detecting free intraperitoneal fluid with the pelvic views of the FAST exam. Am J Emerg Med. 2003 Oct;21(6):476-478.</ref>, though >500ml is needed for the common user<ref>McKenney KL, McKenney MG, Cohn SM, et al. Hemoperitoneum score helps determine need for therapeutic laparotomy. J Trauma 2001; 50(4):650–654.</ref>
*If blunt trauma start with RUQ view first
*In penetrating start with cardiac views first to rule out tamponade
*Serial exams extremely helpful
*Serial exams extremely helpful


==Stable vs Unstable==
==Indications==
[[File:Free fluid 2.png|thumb|Positive FAST (RUQ)]]
*FAST is useful in patients with blunt or penetrating traumatic injury
[[File:Free fluid.png|thumb|Positive FAST (RUQ)]]
*Enables trauma bay decision:
[[File:Free fluid 3.png|thumb|Positive FAST (LUQ)]]
**Stable patient with traumatic mechanism of injury + negative FAST → observation
*Views: hepatorenal, splenorenal, pelvis, pericardium
**Stable patient with traumatic mechanism of injury + positive FAST → CT
*Stable patient + negative FAST → observation
**Unstable patient with traumatic mechanism of injury + negative fast → repeat FAST or CT
*Stable patient + positive FAST → CT
**Unstable patient with traumatic mechanism of injury + positive FAST → laparotomy
*Unstable patient + negative fast → repeat FAST or DPL
*Unstable patient + positive FAST → laparotomy


==Procedure==
==Technique==
*Always point dot to patient Rt (usu at 45 degrees) or @ patient head
#Select probe
*Morison's Pouch
#*Curvilinear/large convex probe is ideal but phased array probe may be substituted
**Best seen with probe around mid ax to ant ax line (esp with patient in trendelenburg)
#Location
**Pitfall: fan completely through (must visualize liver tip), assess pleural space  
#*Sequence can vary depending on mechanism of injury
*[[Ultrasound: Renal]]
#*Include cardiac, RUQ, pelvic, and LUQ views
*Splenorenal
===Cardiac===
**Place probe in post ax line
#Location
**Pitfall: Look superior to spleen for fluid, not just splenorenal
#*Subxiphoid
**Troubleshooting: Slide probe as posteriorly as possible, have patient hold breath if able to
#Landmarks
*Bladder
#*Visualize the heart and pericardium using the liver as an acoustic window
**Pitfall: turn down gain to view posterior bladder (posterior acoustic enhancement)
#Scan anterior to posterior through the heart
**[[Ultrasound: Bladder]]
===RUQ===
*Cardiac
#Location
**Assess for pericardial effusion
#*Coronal view over the right flank
**see [[Ultrasound: Cardiac]]
#Landmarks
*E-FAST
#*Visualize the interface between the liver and kidney
**Add on pulmonary views to evaluate for pneumothorax
#Scan anterior to posterior identifying Morison’s pouch and the superior and inferior pole of the kidney
**[[Ultrasound: Lungs]]
===Pelvic===
#Location
#*Sagittal view just superior to the pubic symphysis
#Landmarks
#*Identify the bladder
#Scan medial to lateral to identify fluid posterior and superior to the bladder
 
===LUQ===
#Location
#*Coronal view over the left flank
#Landmarks
#*Identify the space between the spleen and diaphragm and the spleen and the kidney
#Scan through anterior to posterior of the splenodiaphragmatic space and superior and inferior pole of the kidney
 
==Findings==
*Positive FAST will have one of the following:
**Anechoic area within the pericardial space
**Anechoic areas between the liver and kidney
**Anechoic areas between the diaphragm and spleen
**Anechoic areas between the spleen and kidney
**Anechoic areas between superior and posterior to the posterior wall of the bladder
 
==Images==
===Normal===
<gallery>
File:Subxiphoid (Still).gif|Normal subxiphoid view
File:No hydro still.jpg|RUQ with no free fluid
File:Normal sagittal bladder.jpg
</gallery>
===Abnormal===
<gallery>
File:Pericardial Effusion.png|Pericardial effusion
File:Free fluid 2.png|thumb|Positive FAST (RUQ)
File:Free fluid.png|thumb|Positive FAST (RUQ)
File:FF near bladder.png|Free fluid superior to the bladder
File:Free fluid 3.png|thumb|Positive FAST (LUQ)
</gallery>
 
==Pearls and Pitfalls==
*Morison’s pouch
*Scans must scan through the inferior poles of the kidneys as this can contain small quantities of fluid
*Serial exam may be needed
*Negative exam does not rule out intraabdominal injuries
*Retroperitoneal hemorrhage no easily identified
*Those with delayed presentation may have clotted and not completely anechoic fluid collections
 
==Documentation==
===Normal Exam===
A bedside FAST ultrasound was conducted to assess for free fluid with clinical indication of trauma. Cardiac, RUQ, pelvic, and LUQ views were adequately obtained. There was no free fluid identified.
===Abnormal Exam===
A bedside FAST ultrasound was conducted to assess for free fluid with clinical indication of trauma. Cardiac, RUQ, pelvic, and LUQ views were adequately obtained. There was free fluid identified in the RUQ suggesting intraabdominal hemorrhage.
 
==Clips==
===Normal===
<gallery>
File:Normal subxiphoid.gif
File:Bladder sagittal.gif|Normal pelvic view
</gallery>
===Abnormal===
<gallery>
File:Free fluid at the liver tip.gif|Free fluid located at the liver tip
</gallery>
 
==External Links==
*[http://www.sonoguide.com/FAST.html Sonoguide: Ultrasound in Trauma – The FAST Exam]
*[http://emcrit.org/podcasts/fast-exam/ EMCrit: Podcast 102 – Don’t Half-Ass your FAST!]


==See Also==
==See Also==
Line 40: Line 106:
*[[Ultrasound: Lungs]]
*[[Ultrasound: Lungs]]
*[[Ultrasound (Main)]]
*[[Ultrasound (Main)]]
*[[Ultrasound: Renal]]
*[[ Renal ultrasound]]
*[[Bladder ultrasound]]
*[[Abdominal Trauma]]
*[[Abdominal Trauma]]
*[[Ultrasound: In Shock and Hypotension]]
*[[Ultrasound: In Shock and Hypotension]]
Line 46: Line 113:
==References==
==References==
<references/>
<references/>
Sonoguide
UTZ textbook


[[Category:Ultrasound]]
[[Category:Radiology]]
[[Category:Radiology]]
[[Category:Trauma]]
[[Category:Trauma]]
[[Category:Ultrasound]]

Revision as of 13:20, 18 July 2016

Background

  • Prioritize: Do primary survey of ATLS first ABCDE
  • FAST exam follows ABCDE to assess “C” looking for free fluid
  • Sensitivity of 42% and specificity of ≥98%[1][2]
  • As little as 100ml of free fluid can be seen[3][4], though >500ml is needed for the common user[5]
  • If blunt trauma start with RUQ view first
  • In penetrating start with cardiac views first to rule out tamponade
  • Serial exams extremely helpful

Indications

  • FAST is useful in patients with blunt or penetrating traumatic injury
  • Enables trauma bay decision:
    • Stable patient with traumatic mechanism of injury + negative FAST → observation
    • Stable patient with traumatic mechanism of injury + positive FAST → CT
    • Unstable patient with traumatic mechanism of injury + negative fast → repeat FAST or CT
    • Unstable patient with traumatic mechanism of injury + positive FAST → laparotomy

Technique

  1. Select probe
    • Curvilinear/large convex probe is ideal but phased array probe may be substituted
  2. Location
    • Sequence can vary depending on mechanism of injury
    • Include cardiac, RUQ, pelvic, and LUQ views

Cardiac

  1. Location
    • Subxiphoid
  2. Landmarks
    • Visualize the heart and pericardium using the liver as an acoustic window
  3. Scan anterior to posterior through the heart

RUQ

  1. Location
    • Coronal view over the right flank
  2. Landmarks
    • Visualize the interface between the liver and kidney
  3. Scan anterior to posterior identifying Morison’s pouch and the superior and inferior pole of the kidney

Pelvic

  1. Location
    • Sagittal view just superior to the pubic symphysis
  2. Landmarks
    • Identify the bladder
  3. Scan medial to lateral to identify fluid posterior and superior to the bladder

LUQ

  1. Location
    • Coronal view over the left flank
  2. Landmarks
    • Identify the space between the spleen and diaphragm and the spleen and the kidney
  3. Scan through anterior to posterior of the splenodiaphragmatic space and superior and inferior pole of the kidney

Findings

  • Positive FAST will have one of the following:
    • Anechoic area within the pericardial space
    • Anechoic areas between the liver and kidney
    • Anechoic areas between the diaphragm and spleen
    • Anechoic areas between the spleen and kidney
    • Anechoic areas between superior and posterior to the posterior wall of the bladder

Images

Normal

Abnormal

Pearls and Pitfalls

  • Morison’s pouch
  • Scans must scan through the inferior poles of the kidneys as this can contain small quantities of fluid
  • Serial exam may be needed
  • Negative exam does not rule out intraabdominal injuries
  • Retroperitoneal hemorrhage no easily identified
  • Those with delayed presentation may have clotted and not completely anechoic fluid collections

Documentation

Normal Exam

A bedside FAST ultrasound was conducted to assess for free fluid with clinical indication of trauma. Cardiac, RUQ, pelvic, and LUQ views were adequately obtained. There was no free fluid identified.

Abnormal Exam

A bedside FAST ultrasound was conducted to assess for free fluid with clinical indication of trauma. Cardiac, RUQ, pelvic, and LUQ views were adequately obtained. There was free fluid identified in the RUQ suggesting intraabdominal hemorrhage.

Clips

Normal

Abnormal

External Links

See Also

References

  1. Natarajan B, Gupta PK, Cemaj S, et al. FAST scan: Is it worth doing in hemodynamically stable blunt trauma patients? Surgery. 2010;148(4):695-700.
  2. Miller MT, Pasquale MD, Bromberg WJ, et al. Not so FAST. J Trauma. 2003; 54(1):52-59.
  3. Goldberg GG. Evaluation of ascites by ultrasound. Radiology. 1970; 96(15):217–221.
  4. Von Kuenssberg Jehle D, Stiller G, Wagner D. Sensitivity in detecting free intraperitoneal fluid with the pelvic views of the FAST exam. Am J Emerg Med. 2003 Oct;21(6):476-478.
  5. McKenney KL, McKenney MG, Cohn SM, et al. Hemoperitoneum score helps determine need for therapeutic laparotomy. J Trauma 2001; 50(4):650–654.