Bedside ultrasound is an optimal first-line imaging modality for the evaluation of peritoneal free fluid. The focused assessment with sonography in trauma (FAST) examination is one of the first point-of-care, multi-organ system assessments described in literature. Although computed tomography (CT) is generally more sensitive and specific for diagnosing solid organ injury, pneumothorax, hemoperitoneum and other acute injuries, ultrasound involves no ionizing radiation, intravenous contrast, and can generally be performed and interpreted much more rapidly [1, 2]. This is especially helpful in patients too unstable for transport to Radiology. The benefits of bedside ultrasound are now commonly extended beyond trauma evaluations to search for free fluid in the non-traumatic patient and in other disease processes. It can be used to evaluate for free peritoneal fluid in patients with end-stage liver disease, renal disease, congestive heart failure, or ruptured ectopic pregnancy and guide the optimal site for paracentesis. Bedside ultrasound for free fluid can expedite patient care and definitive treatment .
KeywordsPeritoneum Perforation Hemopertitoneum Ascites
Ultrasound video of the normal right upper quadrant. Adjust the transducer position and angle to visualize the right upper quadrant, focusing on the potential space between liver and kidney (hepatorenal recess, or Morison’s pouch). Fan the transducer from anterior to posterior through the entire hepatorenal recess to visualize the inferior tip of the liver, looking for free fluid. The inferior pole of the right kidney should be visualized along with the right paracolic gutter. Angle the transducer superiorly to image the right subdiaphragmatic space. The area immediately above (cephalad to) the diaphragm can be visualized as well to exclude fluid in the thorax. Video courtesy of Pimpa Limphan-udom (MP4 2658 kb)
Ultrasound video of the normal left upper quadrant. Fan the transducer through the perisplenic space from anterior to posterior. The inferior poles of the kidney and spleen should be visualized along with the superior portion of the left paracolic gutter. Video courtesy of Pimpa Limphan-udom (MP4 2175 kb)
Ultrasound video of the normal pelvis in the transverse plane. Fan the transducer inferiorly into the pelvis until the bladder is visualized. Set the imaging depth to view the bladder in the top one-third to one-half of the screen. Posterior acoustic enhancement should be appreciated posterior to the bladder. It is important to fan the transducer to visualize the entire bladder from fundus to neck to thoroughly evaluate the rectovesicular or rectouterine spaces for a free fluid collection. Video courtesy of Pimpa Limphan-udom (MP4 2600 kb)
Ultrasound video of the normal pelvis in the longitudinal plane. Scan the entire bladder from left to right. Video courtesy of Pimpa Limphan-udom (MP4 2560 kb)
Ultrasound video of the pneumoperitoneum. Sagittal sonographic section of the right hypochondrium using a curvilinear probe showing enhanced peritoneal stripe and reverberation artifacts. Note that free air just beneath the peritoneum helps create a reverberation artifact between the peritoneum and skin. Air beneath the peritoneum thus creates an artifact much A-lines (created by air beneath the pleura). Although the appearance of A-line artifacts generally signifies normal lung, the same appearance is highly suspicious for pneumoperitoneum when visualized in the abdomen. Video courtesy of Bret Nelson (MP4 626 kb)
- 3.Thierman JS. Ultrasound evaluation of peritoneal fluid. In: Carmody KA, Moore CL, Feller-Kopman D, eds. Handbook of critical care and emergency ultrasound. New York: McGraw-Hill; 2011. http://accessanesthesiology.mhmedical.com/content.aspx?bookid=517§ionid=41066795. Accessed 27 June 2017.