Stone | Extracorporeal Shock Wave Lithotripsy (ESWL)

Description of Procedure

ESWL a procedure in which sound waves are focused on stones and used to fragment the stones into smaller pieces which can pass on their own. The shockwaves are targeted using fluoroscopy (a type of x-ray which is relatively low dose but can show imaging in real-time).

 

The procedure is done under light sedation. It is important to lie very still on the bed so that targeting can be as accurate as possible. Even a small movement will mean that sound waves may not be hitting the stone as desired.

 

ESWL is an excellent choice for:

  1. Stones in the kidney less than 1-2 cm. Larger stones may be better treated with PNL
  2. Stones in the upper ureter. Stones in the lower ureter are often bettter treated with ureteroscopy.

 

In some cases, a ureteral stent will be placed prior to ESWL to reduce the chances that a fragment will obstruct the ureter. This is especially so with larger stones.

 

In 2006, a group from the Mayo Clinic published an observational series on a large group of patients who received ESWL. The study, which had some serious methodological flaws, suggested that there was an increased incidence of diabetes and hypertension in patients whom had undergone ESWL. Subsequently, the Mayo group (in 2012) and several other groups have shown that there is NOT an increased risk of developing diabetes or high blood pressure following ESWL and it should be considered safe in that regard.

 

Preparation

 

DOWNLOAD THE PRE-PROCEDURE ESWL INSTRUCTIONS HERE

 

  • You will be requested to obtain some blood work including an electrocardiogram prior to the procedure
  • The afternoon prior to the procedure a bowel preparation is required. taking 1/4 to 1/2 a bottle of Citromag with fluids will help clear the colon and allow for visualization of the stone and the past outcome.
  • You will need to fast before coming for the procedure starting from midnight onwards.
  • It is important to stop anticoagulants and antiplatelet medications (examples include Coumadin/warfarin, aspirin, Plavix) for 7-10 days prior to the procedure

On the Web

American Urological Association Information on ESWL

Canadian Urological Association Information on ESWL

Vancouver Coastal Health Discharge Instructions following ESWL

 

After Procedure

If you have questions that are not answered here, please contact us.

What to Expect

  • The following should be considered normal for a couple of days following this procedure: some flank pain and mild bruising, blood in the urine, passage of debris
  • You will be provided with a strainer to collect stone. It may appear as gravel or sand. Please bring this in with you to your follow-up appointment.

 

Cautions

  • You should NOT have fever or severe pain. Please proceed to emergency and inform your urologist if you encounter these problems.
  • If you are having intractable pain unresponsive to pain medications, proceed to emergency. You are likely passing a fragment which is stuck in the ureter. These sometimes require retreival with ureteroscopy.

 

Diet

  • There are no dietary restrictions. Information on preventing stone by modifying your diet and behavior can be found here.

Activity

  • You may resume normal activities 24 hours after the procedure so long as the urine appear clear and you are not having ongoing pain.

Medications

  • You will be provided with a prescription for pain medication after your procedure. You can resume all of your medications unless otherwise instructed.

Follow-up

Your urologist but want to see you approximately 1-2 weeks after the procedure to determine if you have passed any stone fragments (please bring these with you). A plain x-ray of the kidney will also be performed to check for residual stones.