Scanning the Pericardial Space

Place the probe in the subxiphoid space with the probe marker to the right and right of midline. Utilize the liver as an acoustic window. The angle of the probe with the skin may be as shallow as 5-10 degrees. The patient’s inherent respiratory pattern will bring the heart closer to and farther from the probe.

Adjust the depth to allow visualization of the posterior bright white pericardium. A black stripe of fluid separating the hyperechoic pericardium from the gray myocardium is concerning for a traumatic pericardial effusion (see image 5).

Scanning the Hepatorenal Space

Place the probe in the anterior axillary line at the inferior portion of the thoracic cage with the probe marker pointed toward the head in a coronal plane. Scan cephalad and caudad in this or the mid-axillary line until the clear interface of the liver and kidney are viewed (see image 6). To image the inferior pole of the right kidney, rotate the probe obliquely, as this approximates the normal anatomic lie of the organ. Intraperitoneal fluid appears as a black hypoechoic or anechoic stripe in the hepatorenal interspace (see image 7).

Scanning the Splenorenal Space

Place the probe in the mid or posterior axillary line at the inferior portion of the thoracic cage, with the probe marker pointed toward the head in the coronal plane.

Note that the left kidney is anatomically positioned more superior than the right kidney; for this reason, the probe is positioned more cephalad to view the interface. Scan cephalad and caudad in this or the mid-axillary line until the clear interface of the spleen and kidney is viewed.

To image the inferior pole of the left kidney, rotate the probe obliquely, because this approximates the anatomic lie of the organ. Intraperitoneal fluid appears as a black hypoechoic stripe in the splenorenal interspace (see image 8).

Scanning the Pleural Spaces

Using the same probe in the same position as for evaluation of the hepatorenal and splenorenal spaces, slide the probe cephalad one rib space for evaluation of the area above the diaphragm.

The presence of mirror imaging of the liver or spleen above the hyperechoic line representing the hemidiaphragm is evidence against pleural fluid (see image 9). If this area appears black or anechoic, there should be concern for pleural fluid proximal to the dia-phragm (see image 10). For the right pleural space, the probe would be located in the anterior axillary line between the sixth and ninth intercostal spaces. If a rib shadow precludes the ability to evaluate this area, rotate the probe obliquely toward the back.