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Emergency Ultrasound: The FAST Exam
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ULTRASOUND IN TRAUMAPetra Duran-Gehring, M.D.
University of Florida- Jacksonville
Objectives
Describe the indications and limitations of bedside ultrasound in trauma
Define the relevant local anatomy Understand the ultrasound protocol used
in the setting of trauma Recognize the relevant findings and
pitfalls in the detection of hemoperitoneum, hemopericardium and hemothorax
History
1970s: US first used to evaluate trauma patients in Europe
1980s: FAST replaces DPL in most trauma centers
1988: German Surgery Board requires US certification
1997: FAST included in ATLS course 2001: US training required in EM
residencies
Radiologic Evaluation in Trauma CT: non-invasive, gives detail about
organs DPL: most sensitive, invasive US: non-invasive, can detect 250cc of
free fluid in Morrison’s Pouch
What is FAST?
Focused
Assessment with
Sonography in
Trauma
Objective: Detection of
intra-abdominal free fluid
Detection of pericardial fluid
E-FAST: detection of hemothorax and pneumothorax
FAST
Benefits Performed rapidly Noninvasive Inexpensive Easily repeatable Highly specific for
therapeutic laparotomy
Limitations Obesity Subcutaneous
emphysema Non-specific
Indications
Rapid detection of: Hemoperitoneum Pericardial Effusions Pleural Effusions
Abdominal Trauma Chest Trauma
Abdominal Trauma
Blunt trauma Most widely studied Intraperitoneal bleeding due to splenic or
liver injury Penetrating trauma
50% sensitivity for determining the need for laparotomy
Doesn’t detect bowel injury Can still determine hemoperitoneum
Chest Trauma
Penetrating trauma Pericardial Effusion
Pericardium seals self creating effusion leading to tamponade
US identifies prior to Beck’s triad Screening exam for effusion
Hemothorax US more sensitive than CXR (20ml vs. 200ml for
detection) Extended FAST for pneumothorax, sensitive for
supine pts Blunt trauma
May determine cardiac rupture
Why FAST works
Fluid pools in predicable locations Subhepatic Perinephric Perisplenic Pelvic Subpleural
Position patient to best locate fluid Trendelenburg for upper quadrants Reverse trendelenburg for pelvis
FAST Anatomy
Phrenicolic
Ligament
Transverse Colon Mesentery
Morrison’s Pouch
Pelvis
Equipment
Probe 2-5 MHz Curved array Small footprint
Machine Maneuverable Color flow Doppler
FAST Components
Right Upper Quadrant
Left Upper Quadrant
Cardiac Subxiphoid Parasternal long
axis Suprapubic Extended FAST
Lung fields
Right Upper Quadrant
Position Probe placed with
indicator to pt’s head Probe placed around 8-
11th rib space, mid axillary line
May need to slide probe around rib shadow
Do not forget to interrogate inferior pole of kidney
RUQ
Liver
KidneyDiaphragm
Morrison’s Pouch
RUQ
Includes Liver Kidney Morrison’s pouch Diaphragm (E-FAST)
Look for: Fluid in Morrison’s pouch Lack of mirror artifact
Normally diaphragm acts as mirror, liver appears to be on either side
Indicates pleural fluid
RUQ Free Fluid
Intraperitoneal fluid Morrison’s Pouch Along the lower edge of
the liver Superior to liver
Pleural fluid Lack of mirror artifact Lung appears to float
with inhalation
RUQ Free Fluid
RUQ Free Fluid
Left Upper Quadrant
Position Probe placed with
indicator to pt’s head Probe placed around 6-
9th rib space, mid axillary line
May be difficult to achieve due to rib shadow
Ask pt to inhale deeply to displace anatomy inferiorly
LUQ
Kidney
Spleen
Diaphragm
LUQ
Includes Spleen Kidney Diaphragm (E-FAST)
Look for:
Fluid in spleenorenal fossa
Fluid inferior to spleen Lack of mirror artifact
LUQ Free Fluid
Intraperitoneal Fluid Splenorenal fossa Inferior to inferior pole of
spleen Superior to spleen
Pleural Fluid Lack of mirror artifact Lung floating with
inspiration
Cardiac View
May use either: Subxiphoid Parasternal long axis
Look for Cardiac activity Pericardial effusion RV collapse
Cardiac Limitations
View dependant on patient habitus and condition
Subxiphoid better COPD
Parasternal better Pregnancy Obesity Abdominal pain
Subxiphoid View
Position Probe placed in
epigastrium Probe indicator to
patient’s right Probe tip pointing
to pt’s left shoulder
Increase depth
Subxiphoid View
Four chamber view
Apex to right of screen
Left side at bottom of screen
Liver
RA
LA
LV
RV
Mitral Valve
Bicuspid Valve
Subxiphoid View
LV
LA
RA
RV
ApexLiver
Subxiphoid View
Parasternal View
Probe placed to the left of the sternum at 2-4th intercostal space
Long Axis Probe indicator to
patient’s right shoulder
Sagital plane
Parasternal Long Axis View
Three chambers in view LV LA RV
Aortic Root Valves
Mitral Aortic
LALV
RV
Mitral Valve
Aortic Outflow Tract
Aortic Valve
Parasternal Long Axis View
LV
RV
LA
Aortic root
Parasternal Long Axis View
Pericardial Effusion
Pericardial Effusion
Pericardial Tamponade
RV collapse
Pericardial Tamponade
RV collapse
Suprapubic
Position Transverse
Probe in the midline just cephalad to the pubic bone
Probe indicator pointed to pt’s right
Longitudinal Probe in the midline
just cephalad to the pubic bone
Probe indicator pointed to pt’s head
Suprapubic
Identify Bladder Uterus in women Pouch of Douglas
Look for Fluid: Men: posterior to bladder Women
Vesicouterine space Posterior to uterus
(Pouch of Douglas) Sharp edges indicate
fluid outside of bladder
Suprapubic
Bladder
Uterus
Bladder
Pouch of Douglas
Pouch of
Douglas
Pelvic Free Fluid
Posterior to bladder
Pelvic Free Fluid
Pouch of Douglas
Extended FAST
Addition to 4 view FAST exam Includes evaluation for hemothorax and
pneumothorax Two additional components
Expand UQ views to visualize diaphragm Lack of mirror artifact indicates
fluid/hemothorax Scan anterior chest
Lack of lung slide indicates pneumothorax
Hemothorax
Includes Liver or spleen Kidney Diaphragm
Look for: Lack of mirror
artifact Normally
diaphragm acts as mirror, liver appears to be on either side
Indicates pleural effusion
Hemothorax
Hemothorax
diaphragm
lung
Pneumothorax (ptx)
Occurs in 15-50% of pts with chest trauma Supine CXR
Misses up to 1/3 of all pneumothoraces Only 50-70% sensitive at detection ptx Inaccurate for anterior ptx due to air layering
Ultrasound Detects small or anterior ptx Sensitivity 92-100% (equal to CT scan) Negative predictive value 99-100%
Pneumothorax
Use high frequency linear probe (5-10 MHz)
Place probe on anterior chest wall, indicator to pt’s head
Slide down chest wall to interrogate each rib interspace
Lung Fields
Includes Rib with shadow Subcutaneous tissue
and muscle Pleura
Look for: Slide of the pleura Lack of sliding indicates
pneumothorax
Lung Anatomy
ribrib
pleura
Pneumothorax
Watch for slide of the pleura
Lack of sliding indicates pneumothorax B-Mode: direct
visualization M-Mode: “sandy
beach” May see the
leading edge of pneumothorax
Normal Lung Slide
Pneumothorax: no slide
Lung Slide
Normal Lung Pneumothorax
M-Mode
Normal Pneumothorax
“sandy beach” “bar code”
Other US Uses in Trauma
Diaphragmatic injury Evaluated using M-Mode Watch for motion
Fractures Can be used for closed reduction
Ocular
Fracture
Look for the hyperechoic bone with distal shadowing
Look for a disruption in the bony cortex
Subtle fractures on X-ray, more obvious on US
Fracture
Bone
Fracture
Ocular
Increased ICP Measure optic
nerve diameter Papilledema Retinal
Detachment Foreign Body
Ocular
Retina
Lens
Anterior Chamber
Optic Nerve
Increased ICP
Measure the optic nerve Measure 3mm
down from retina Measure diameter
of nerve at that point
Measurements greater than 5mm indicate increased ICP (>20mmHg)
Papilledema
Retinal Detachment
CASES
Case 1
18 y/o male unrestrained driver in high speed MVC
Arrived in c-collar and backboard with NRBM in place
Vitals: BP 84/41, P 121, R 30 & shallow, Pox 99% on NRBM
Case 1
PE: Moaning incoherantly, GCS 14 HEENT: PEERL 4mm, multiple facial lacs,
midface stable CHEST: decreased BS on R, no crepitus ABD: multiple abrasions, diffuse TTP EXT: pelvis stable, multiple abrasions, no
obvious deformity 2 large bore IVs placed Bedside US performed
Case 1 FASTRUQ LUQ
PELVISSUBX
Case 1 Chest US
Case 1
Chest tube was placed on R with a rush of air
Pt remained hypotensive and went to OR Found to have splenic lac and spleen
removed Admitted to trauma ICU
Case 2
84 y/o female restained driver in side impact MVC at 50mph
C/o pain in abd and L hip Arrives in full spine immobilization and
traction splint to L leg VS: BP 90/50, P 60, R 20, Pox 100% RA
Case 2
PE: GCS 15 HEENT: PEERL 4mm, NCAT CHEST: equal BS B, non labored ABD: Linear abrasion with ecchymosis
across abd, diffuse TTP EXT: pelvis stable, L femur TTP with
shortening and internal rotation 2 large bore IVs placed Bedside US performed
Case 2 FAST
RUQ LUQ
PELVIS SUBX
Case 2 L Femur US
Case 2
BP improved after IV fluids Ortho was consulted and placed a
traction pin for the proximal femur fracture
CT scan of the abdomen revealed a grade 1 liver laceration
Pt was admitted and the laceration was monitored but did not require surgery
Questions?????