Lithotripsy
What is lithotripsy?
Lithotripsy is a procedure used to treat kidney stones that are too large to pass
through the urinary tract. It works by sending focused ultrasound energy as shock
waves directly to the stone. The shock waves break a large stone into smaller stones
that will pass through the urinary system. Lithotripsy lets people with certain types
of kidney stones possibly not need surgery. To find the stone, healthcare providers
use fluoroscopy. This is a series of moving X-ray pictures. They may also use ultrasound
to find the stone.
There are two types of shock wave technology. In the original method, the person is
placed in a tub of water through which the shock waves are sent guided by X-rays or
ultrasound. This method is still in use. In a second method, the person lies on a
soft cushion and the shock waves pass through that. This method is more common.
Why might I need lithotripsy?
When substances normally excreted through the kidneys stay in a kidney, they may crystallize
and harden into a kidney stone. If the stones break free, they can get stuck in the
narrower passages of the urinary tract. Some kidney stones are small or smooth enough
to pass easily through the urinary tract without discomfort. Other stones may have
rough edges or grow as large as a pea or more. These can cause great pain as they
move through or block the urinary tract. The areas that are more prone to trapping
kidney stones are the bladder, ureters, and urethra.
Most kidney stones are small enough to pass without treatment. But about 1 in 5 cases,
the stone is greater than 2 cm (about 1 inch) and may need treatment. Most kidney
stones are made of calcium. But there are other types of kidney stones. Types of kidney
stones include:
-
Calcium stones. Calcium is a normal part of a healthy diet and used in bones and muscles. It's normally
flushed out with the urine. Excess calcium not used by the body may mix with other
waste products to form a stone.
-
Struvite stones. Struvite stones are made of magnesium, phosphate, and ammonia. They may form after
a urinary tract infection.
-
Uric acid stones. Uric acid stones may form when urine is too acidic. This can happen when you have
gout or certain cancers.
-
Cystine stones. These stones are made of cystine. This is one of the building blocks that make up
muscles, nerves, and other parts of the body.
When kidney stones get too large to pass through the urinary tract, they may cause
severe pain and may block the flow of urine. This can cause infection and problems
with how the kidneys work.
There may be other reasons for your healthcare provider to advise lithotripsy.
What are the risks of lithotripsy?
Risks of lithotripsy may include:
-
Bleeding around the kidney. It's common for there to be small amounts of blood in
the urine for a few days after the procedure.
-
Infection
-
Blockage of the urinary tract by pieces of stone. This can lead to kidney failure
in extreme cases.
-
Pieces of stone that aren't passed from the body may need more lithotripsy treatments.
Obesity and intestinal gas may interfere with a lithotripsy treatment.
-
Excessive pain or discomfort
Not everyone is able to have lithotripsy, including:
-
Women who are pregnant. This treatment is unsafe for a fetus.
-
People who have a large aortic aneurysm
-
People with certain bleeding conditions
-
Those with certain skeletal deformities that prevent accurate focus of shock waves
Tell your healthcare provider if you have a heart pacemaker. Lithotripsy may be done
on people with pacemakers with the approval of a cardiologist and by using certain
precautions. Be sure to discuss any concerns with your provider before the procedure.
You may want to ask your provider about the amount of radiation used during lithotripsy.
It is a good idea to keep a record of your radiation exposure, such as previous scans
and other types of X-rays, so that you can tell your provider. Radiation risks may
be related to the cumulative exposure over time.
How do I get ready for lithotripsy?
-
Your healthcare provider will explain the procedure, and you can ask questions.
-
You'll be asked to sign a consent form that gives your permission to do the procedure.
Read the form carefully and ask questions if something isn't clear.
-
Your provider will ask about your health history. They will also do a physical exam
to make sure you're in good health before having the procedure. You may have blood
or other tests.
-
You may need to fast before the procedure. You'll be given instructions on how many
hours to fast before the procedure if needed.
-
Tell your provider if you're pregnant or think you may be. Pregnant women shouldn't
have lithotripsy because of the risks to the fetus.
-
Tell your provider if you're sensitive to or allergic to any medicines, latex, tape,
or anesthesia.
-
Tell your provider of all medicines (prescription and over-the-counter) and herbal
supplements that you're taking.
-
Tell your provider if you have a history of bleeding disorders or if you're taking
any anticoagulant (blood-thinning) medicines, aspirin, or other medicines that affect
blood clotting. You may need to stop these medicines before the procedure.
-
You may get a sedative or anesthetic before the procedure to help you relax.
-
Based on your medical condition, your provider may ask for other specific preparations.
What happens during lithotripsy?
Lithotripsy may be done on an outpatient basis or as part of a hospital stay. Procedures
may vary depending on your condition and your healthcare provider’s practices.
Generally, lithotripsy follows this process:
-
You'll need to remove any clothing, jewelry, or other objects that may interfere with
the procedure.
-
If you need to remove your clothing, you'll put on a hospital gown.
-
An IV (intravenous) line will be inserted in your arm or hand to give you fluids and
medicines.
-
You may get medicine to help you relax or medicine to stop pain to make sure that
you stay comfortable, still, and pain-free during the procedure.
-
After the sedation has taken effect, you'll be put on a water-filled cushion or immersed
in a water-filled tub.
-
After the stone(s) has been found with fluoroscopy or ultrasound, you'll be positioned
for the best access to the stone.
-
If you're awake during the procedure, you may feel a light tapping feeling on your
skin.
-
A series of shock waves will be sent to shatter the kidney stone(s).
-
The stone(s) will be kept track of by fluoroscopy or ultrasound during the procedure.
-
The medical staff may place a stent, in the ureter before lithotripsy to help keep
the passage open so stone pieces and urine can pass easily.
-
Once the stone fragments are small enough to pass through the urinary system, the
procedure will end.
Talk with your healthcare provider about what you'll experience during your lithotripsy
procedure.
What happens after lithotripsy?
After lithotripsy, you'll be taken to the postanesthesia recovery room for observation.
Once your blood pressure, pulse, and breathing are stable and you're alert, you will
be taken to your hospital room or discharged home. Plan to have someone give you a
ride home. You shouldn't drive for at least 24 hours after getting sedatives for the
procedure.
You may go back to your usual diet and activities unless your healthcare provider
tells you otherwise. Certain stones can be prevented by dietary and lifestyle changes.
You will be encouraged to drink extra fluids to dilute the urine and reduce the discomfort
of passing stone pieces.
You may notice blood in your urine for a few days or longer after the procedure. This
is normal.
You may notice bruising on the back or belly. This is also normal.
Take a pain reliever for soreness only as recommended by your provider. Don't take
aspirin, ibuprofen, or certain other pain medicines. They may increase the chance
of bleeding.
You may be given antibiotics after the procedure. Be sure to take the medicine exactly
as prescribed.
You may be asked to strain your urine so that remaining stones or stone pieces can
be sent to the lab for testing.
A follow-up appointment will be scheduled within a few weeks after the procedure.
If a stent was placed, it may be removed at this time.
Call your healthcare provider right away if you have any of the following:
Your healthcare team may give you other instructions after the procedure, depending
on your particular situation.
Next steps
Before you agree to the test or the procedure make sure you know:
-
The name of the test or procedure
-
The reason you are having the test or procedure
-
What results to expect and what they mean
-
The risks and benefits of the test or procedure
-
What the possible side effects or complications are
-
When and where you are to have the test or procedure
-
Who will do the test or procedure and what that person’s qualifications are
-
What would happen if you did not have the test or procedure
-
Any alternative tests or procedures to think about
-
When and how you will get the results
-
Who to call after the test or procedure if you have questions or problems
-
How much you will have to pay for the test or procedure