Describe the indications, clinical algorithm, and limitations of CUS in blunt and penetrating thoracoabdominal trauma.
Perform the CUS protocol for Trauma in both primary and secondary surveys.
Identify relevant US anatomy including the pleura, diaphragm, inferior vena cava, pericardium, liver, spleen, kidneys, bladder, prostate and uterus.
Recognize pathologic findings and pitfalls in the evaluation of pneumothorax, hemothorax, pulmonary contusion, hemopericardium, cardiac activity, volume status, and hemoperitoneum.
Integrate Trauma CUS findings into individual patient, departmental, and disaster management.

Rapid bedside assessment of the thoracoabdominal region for evidence of traumatic free fluid in the peritoneal, pericardial, and pleural cavities.

RUQ: superior to diaphragm, liver tip, Morrison’s pouch, inferior pole of kidney
LUQ: superior to diaphragm, subdiaphragmatic space, splenorenal space, paracolic gutter
Pelvis: transverse and sagittal views
Cardiac: subxiphoid or parasternal long views
Pleural line: bilateral lungs with lung slide or M-mode

Negative exam does not equal no free fluid; need 100-500 mL present
RUQ and LUQ structures move as the diaphragm contracts, so consider asking your patient to hold their breath
Consider slightly rotating probe counterclockwise to fit the probe better between rib spaces
In pelvis, if you are not able to get proper images, your probe is likely too superior – bladder is directly posterior to pubic bone
In LUQ, the perisplenic space is the most common spot for fluid, not the splenorenal space due to the splenorenal ligament that connects these and prevents fluid accumulation
Adequate pain control, if patient clinical status allows, can allow for improved views
If challenging/limited views despite good positioning and windows, consider pneumoperitoneum. May see the presence of abdominal A-lines
FAST does not reliably identify solid organ injuries or retroperitoneal hemorrhage
Small hemothoraces may be missed in supine position.
Things that can be mistaken for free fluid: fluid in the stomach or bowel, perinephric fat (double line sign), epicardial fat pads, pericardial cysts, descending aorta
Solid organ injuries, mesenteric vascular injuries, hollow viscus injuries, and diaphragmatic injuries may likely not give rise to free fluid so could be missed by FAST