Obviously there are a variety of makes and models of bladder scanners but in essence they function the same way.
The reason for performing this nursing procedure is to accurately determine how much urine is in the bladder.
Many times there are issues with urinary retention that need to be addressed.
Usually, any amount over 150 mls of urine is considered “retention”. Chronically holding urine in the bladder can lead to increased incidences of UTIs (Urinary Tract Infections).
Therefore, determining if there is any retention is of significance.
There are several common reasons for urinary retention. One is that a person may develop neurogenic bladder which is the lack of nerve function to signal voiding and contraction of the bladder.
This can occur with diseases such as Multiple Sclerosis.
Retention may also be due to mechanical obstruction such as BPH (Benign Prostatic Hypertrophy). With BPH, it is usually a chronic issue that develops and worsens over time from incomplete to complete obstruction.
A common symptom of an incomplete obstruction is “frequency” which is the feeling of needing to void very frequently during the day and night but only passing small amounts of urine. This is because the bladder becomes so overly full that the increased pressure in the bladder it is able to push a small amount of urine past any obstruction.
Once that maximum pressure has been relieved just a little, the obstruction closes the urethra again which prevents further emptying. The bladder always remains partially filled, so there isn’t much room for new urine to be held before fullness and need to void occurs again.
This symptom of urinary retention is very similar to a UTI. So how to tell the difference? One simple way to rule out urinary retention is to perform a scan to see how much urine is left in the bladder after the patient voids all he or she can normally.
If at all possible, have the patient void in an upright position. Attempting to void into a urinal or bedpan while lying down can be very difficult for some folks even under the best of situations.
Immediately after the patient voids perform the procedure. What is left in the bladder is called a post voiding residual (PVR).
We used to do a straight catheterization after voiding to measure the actual urine obtained, but this noninvasive procedure is much better for the patient.
The main points to be aware of in order to get an accurate reading are as follows: