Performing a renal study in point-of-care ultrasound (POCUS)
After watching this video, you will know how to acquire and interpret normal images of the kidneys, ureters, and bladder using point-of-care ultrasound (POCUS).
Performing a renal ultrasound at the point-of-care can help you diagnose problems faster. But how do you even start? This video from our Point-of-Care Ultrasound Essentials course will take you through the exact steps to performing a complete renal study. You'll learn how to angle your probe to get the image you need, what views you should look out for, and a nifty tip to help you visualize urine flow.
This video was taken from our POCUS Essentials course taught by Viveta Lobo, MD who is an attending emergency medicine physician and Associate Director, Emergency Ultrasound Fellowship at Stanford University Medical Center in California, USA.
[00:00:00] When acquiring your images for renal scan, you will start in longitudinal axis. Using your phased array probe or your curvilinear probe, place your probe with the indicator towards your patient's head, in a coronal cross section in the lower rib spaces. This is essentially the same position you use when obtaining the right and left upper quadrant views of your FAST exam. To look towards your kidney, you often have to tilt your probe
[00:00:30] posteriorly or aim it towards your patient's back. This is an example of a normal kidney in longitudinal axis. Notice the long cross section of the kidney, with the center hyperechoic region representing the renal pelvis. To obtain your image in short-axis, you're going to rotate your probe 90 degrees to now have your indicator pointing towards the ceiling. This is what your kidney will look like in short-axis. Notice that it will have a more circular shape and your
[00:01:00] renal pelvis will be identified by the bright white hyperechoic region in the center. When performing a renal study, you also need to obtain a short- and long-axis view of your bladder. To obtain your bladder in short- axis, place your phased array probe low on your patient's pelvis and aim towards their feet, indicator to your patient's right. This is an example of a short-axis bladder. You often will be able to identify some pelvic organs, like the prostate, seen here. You then want to flip your
[00:01:30] probe to have your indicator towards your patient's head and identify the bladder in long-axis. Here, you can also identify the uterus posterior to it. You can also evaluate for ureteral obstruction. This is a short-axis image of your bladder and notice these hyperechoic bubble-like structures coming into your bladder. That is actually the spray of urine, from your ureteral jet into your bladder. If you recall, you have
[00:02:00] two jets, one on the right side and one on the left. This helps us evaluate for a ureteral obstruction. Often, it's difficult to identify the flow of urine, as seen in this image. An easier way to do it would be to put color over the right and left ureteral jet and observe the region for color flow, which will occur when there is no ureteral obstruction.