Evaluating the ED patient with undifferentiated shock can be challenging.
Ultrasound can be an invaluable tool in helping to differentiate between hypvolemic, cardiogenic and obstructive shock.
The RUSH exam essentially focuses on the evaluation of the "pump", the "tank" and the "pipes".
The pump: exclude pericardial effusion, global estimate of LV EF, and determine if RV strain is present.
The tank: evaluate the IVC/jugular veins for volume status, look for fluid in the thorax/peritoneum, and exclude pulmonary edema or pneumothorax.
The pipes: look for a ruptured AAA or aortic dissection and DVT.
References
Perera P, Mailhot T, Riley D, Mandavia D. The RUSH Exam: Rapid Ultrasound in Shock in the Evaluation of the Critically Ill. Emerg Med Clin N Am 2010; 28:29-56.
