Air in the urinary bladder is trapped gas caused by certain medical conditions, according to Radiopaedia. Diabetes, the presence of foreign bodies, fungal infections and use of medical devices can cause air to become trapped in the bladder.
The use of catheters and other medical instruments is the most common cause of air in the urinary bladder, according to the University of Virginia School of Medicine. The condition is also known as intravesical air and can be difficult to detect with traditional medical imaging technologies.
The urinary bladder holds urine until it is disposed of through urination, notes Wikipedia. The organ is located at the bottom of the pelvis.