Acute Cholecystitis is a common complications of gallstone disease, and a frequent cause of right upper quadrant pain in patients presenting to the emergency department. ED PoCUS has been shown to be similarly accurate to radiology performed ultrasound when the following sonographic features are present.
Presence of gallstones plus one or more secondary finding
Sonographic Murphy’s sign
Gallbladder wall thickening
Approach to scanning
Visualize the entire gallbladder in both its longitudinal (long axis) and transverse (short axis) to identify gallstones.
General steps for performing PoCUS of gallbladder
The gallbladder is usually situated close to the right anterior axillary line, look for the portal vein which forms the “exclamation sign” with the gallbladder
Use color doppler function to distinguish gallbladder from other fluid filled structure such as the IVC
Troubleshooting tips to optimize your image
Ask the patient to do an inspiratory hold or push the abdomen out. This will cause the liver to shift caudally and push the gallbladder out from the thoracic cage
Place the patient in lateral decubitus position – this helps to bring the gallbladder out from under the ribs and help to displace bowel gas
Lateral approach – start with the RUQ view of FAST scan, locate the hepatorenal interface. Then slowly sweep the bean anteriorly until the gallbladder appears in view
Intercostal approach –consider using a probe with a smaller footprint such as the phase array. Start right midclavicular line, and sweep the probe caudad then cephalad, as well as sliding medial and lateral at each intercostal space.
Once you have identified the gallbladder, sweep slowly in its long and short axis in order to identify for the presence of gallstones, anterior wall thickening, and presence of pericholecystic fluid.
Thanks to local POCUS expert Steve Crandall and RHM Registrar Ralston D’Souza for helping us revise the technique. Check out further study opportunities at Otago Universities postgraduate certificate in ultrasound.