A bladder stress test tries to simulate accidental urine release that occurs if a person coughs, sneezes, laughs or exercises. As part of this test a Bonney test is also performed after verifying that coughing leads to loss of urine. The bladder stress test and the Bonney test are quite similar except that in the latter the bladder neck is raised slightly with an instrument as pressure is applied on the bladder. This is meant to check whether stress pushes down the bladder neck leading to incontinence. If fluid loss occurs during the stress test, the person could be asked to undergo corrective surgery where the bladder neck is raised. If fluid loss occurs after some delay this could point to abnormal bladder muscle contraction, which can be treated with medicines. However, the Bonney test is not easy to standardize and needs a skilled doctor to conduct it in case this test is the determining criterion for whether surgery is to be conducted or not. Any incorrect diagnosis can worsen the condition by wrong treatment.
The bladder stress test and Bonney tests are conducted as part of a physical examination if the patient experiences involuntary urine loss while sneezing, laughing, coughing, or exercising. These tests may also be conducted in case the cause of incontinence remains unknown after checking medical history and conducing a physical examination and urinalysis.
The patient is made to lie down and a thin tube known as a catheter is inserted into the bladder via the urethra. This may cause some discomfort as the catheter is inserted. The catheter is used if the bladder is empty; through it approximately one cup of fluid is poured into the bladder. The catheter is then removed and the patient is asked to cough while the health care provider checks for any loss of fluid. The time interval between the applied stress of coughing and fluid loss are noted. This test may be repeated with the patient standing, in case there is no loss of fluid while lying down.
Before coming for the test, the patient will have to maintain a diary for three to four days noting down what and how often liquids are consumed. The patient will also have to note how often and how much urine was passed and involuntarily leaked. Noting the pattern of urine leakage will provide important clues to the type of incontinence.