Treatment
Basics of Stone Management and Treatment
Most people do not realize that about one third of the kidney is hollow on the inside. This portion is called the collecting system. Kidney stones rest in the collecting system until they attempt to pass down through the ureter toward the bladder. The ureter is the tube that connects the kidney to the bladder.
Stones that are simply resting within the hollow part of the kidney usually do not cause pain. When stones try to pass down the ureter toward the bladder, they have the potential to cause pain. Pain that is the result of a kidney stone occurs when the stone completely or partially blocks the flow of urine from kidney to bladder. This can happen where the kidney meets the ureter or at any point along the course of the ureter. The pressure increases upstream from the point of obstruction and causes severe pain. Think of it like a running garden hose - if someone kinks the hose, all the pressure builds up upstream from the kink. If this happens in the ureter and kidney, then it results in the severe pain and spasms known as "renal colic."
To see a diagram of the Anatomy of the Urinary System.
Expectant Management (trying to pass the stone)
In general, the larger the stone, the less likely it will be to pass. That being said, many patients are able to successfully pass quite large stones, particularly if they have previously passed stones.
- Pain control: for an acute attack of renal colic. Anti-inflammatories such as motrin and naproxen work well. Frequently narcotic medications are necessary to bring the pain under control
- Anti-nausea medications: renal colic goes hand in hand with nausea and vomiting. This is because the nerves that respond to the higher pressures in the kidney also travel to the stomach and cause the stomach to slow down. Anti-nausea medications can provide relief and rest.
- Medical expulsive therapy: recently certain medications have been proven to help patients pass stones in the mid to lower ureter. Your doctor may have started you on such a medication.
- Hydration: staying well hydrated helps move the stone down the ureter toward the bladder. Dehydration can become a problem, particularly for a stone patient with nausea and vomiting.
Minimally Invasive Treatments for Kidney Stones at WakeMed:
Surgical Options - Stones 2 cm or smaller
Shock Wave Lithotripsy (SWL): externally applied sound waves are focused on the stone and used to break it into smaller pieces. Those pieces must then pass down the ureter and into the bladder to be voided out. Overall, there is about an 80% success rate for SWL, however, this varies depending upon the size, location, and composition of the stone.
To see a picture of how SWL works.
For a more detailed description of SWL.
- Benefits of SWL
- Minimally invasive
- Minimal pain
- Outpatient procedure
- Performed under sedation
- Risks/disadvantages of SWL
- Small risk of bleeding around the kidney
- Stone fragments still have to pass and may get stuck along the ureter. This could require a more invasive procedure to remove the stuck fragments.
- Stone may not adequately fragment and could require repeat procedures
- Can only shock one stone per session
Ureteroscopic surgery:
Small flexible telescopes are used to access the urethra, bladder, and ureter. The scope is carefully guided into the ureter and/or kidney where the stone is actually seen by the surgeon. It can then be broken up with a laser fiber and the individual fragments are retrieved with a micro-basket. After the procedure is done, a soft plastic stent is left in place to allow the ureter to heal until the postsurgical swelling has resolved. The stent is later removed with a simple, in-office procedure.
To see a picture of how ureteroscopy works.
To learn more about ureteroscopy.
- Advantages of ureteroscopic surgery
- WakeMed Physician Practices - Urology has a 98% stone free rate after ureteroscopy
- No need to pass stone fragments
- Can treat multiple stones in the same session
- Miminal chance of requiring secondary procedures
- Disadvantages and risks of ureteroscopic surgery
- Risk of injury to ureter
- Requires temporary stenting
- More invasive than SWL
- Usually requires general anesthesia
- Small chance the ureter will be too tight for the scope
Surgical Options – Stones larger than 2 cm
Stones this large are best treated with a procedure called a Percutaneous Nephrolithotomy (PCNL). This is performed by using larger telescopes and instruments placed directly through the back and into the kidney. The stone is then broken up and the pieces are sucked out. A radiologist will place a guidewire through the back immediately prior to surgery to allow access for the larger scopes. After the procedure, the patient will have 2 catheters coming out of their back. One is usually removed the day after surgery and the larger tube is usually removed a few days later in the office. Typically a PCNL requires an overnight stay in the hospital.
See a picture of how PCNL works.
- Advantages of PCNL
- Most effective and efficient way to remove large kidney stones
- Replaces open stone surgery, which required a large incision and 3-4 day hospitalization
- Short hospital stay
- Minimally invasive
- Risks of PCNL
- Risk of bleeding and hematoma around kidney
- Requires having a temporary tube coming out of the back to drain the kidney
- Rare risk of injury to adjacent organs