Lithotripsy

Extracorporeal shockwave lithotripsy (ESWL) is the application of special sound waves (shockwaves) which are directed through the skin and on to urinary tract stones. These shockwaves are produced by a machine called a lithotripter and are guided on to stones using either ultrasound or x-rays. The stones are broken up into tiny fragments which can then be passed out in the urine. The advantage of lithotripsy is that most (about 80%) stones can be treated this way avoiding surgery and general anaesthesia.

A patient lying on a lithotripter machine

Lithotripsy is generally a very safe procedure with a few well recognised side effects. The majority of patients do not suffer any problems afterwards.

Common (greater than 1 in 10)

• Passing blood in the urine temporarily afterwards is normal
• Pain as small fragments pass out (20%) 2 3
• Urinary tract infection requiring antibiotics (10%)
• Failure to break the stone needing an alternative treatment
• Recurrence of stones
• Bruising on the skin where the shockwaves pass through.

Occasional (between 1 in 10 and 1 in 50)

• Stone fragments getting stuck in the ureter (tube connecting the kidney to the bladder) causing pain and hospital admission, and occasionally requiring surgery to unblock the kidney with an internal tube called a stent.

Rare (less than 1 in 50)

• An infection requiring hospital admission and intravenous antibiotics (<1%). Occasionally the kidney has to be drained by a small tube passed through the back and into the kidney.
• Bleeding or bruising in and around the kidney called a haematoma (<1%).

Some stones may be observed and pass spontaneously. This is usually aided by taking medication to relax the tubes. Alternatively surgery maybe considered requiring a general anaesthetic:

• Ureteroscopy. This is where a small telescope is passed up through the natural tubes to the stone, which is destroyed and removed with a laser.
• PCNL. This is a keyhole operation where a telescope is passed through a small cut on the back and into the kidney. This is used for very large stones.
• Open surgery. This has all but disappeared with advances in minimally invasive surgery.

There are certain patients for whom lithotripsy is contra-indicated:

• Patients who are pregnant
• Patients on anticoagulants (blood thinners) such as: warfarin, clopidogrel, high dose Aspirin, Apixaban or Rivoroxaban.
• Patients with pacemakers or internal defibrillators
• Patients who have recently had a heart attack
• Patients with untreated / uncontrolled high blood pressure
• Patients with abdominal aneurysms or an artificial blood vessel graft.

Foods to try and avoid 2 days before treatment begins as the build-up of bowel gas can obstruct the vision of the x-rays in seeking the stone. Please read the following:

Food to avoid 

• Weetabix
• Shredded Wheat
• All Bran
• Bran Cereals
• Wholemeal flour, wholemeal bread
• Cakes and pastries made with wholemeal flour
• Lentils, pulses, beans, baked beans
• All types of vegetables
• Dried fruit
• Spicy food
• Pickles
• Fizzy drinks.

Foods Allowed

• Cornflakes
• Rice Krispies
• Rice
• White bread
• Cakes, biscuits and pastry
• Pastries made with white flour
• Potatoes
• Root vegetables
• Tinned fruit
• Butter
• Margarine
• Clear soups, gravy, Oxo, Marmite, Bovril
• Tea, coffee, coco, Horlicks
• Sugar, jelly and honey

You will be asked to attend the Lithotripsy centre at Princess Royal Hospital at Hayward’s Heath. When you arrive at the hospital follow the signs to the first floor and Ansty ward. Once checked in at the reception desk at urology Out patient department. Please take a seat in the comfortable waiting area specifically for lithotripsy patients (The first door on the right as you enter the ward). You will be given appointment times however some previous patients treatment may take longer than expected so please do allow time for this.

Take painkillers an hour before treatment begins. (Such as paracetamol, Ibuprofen, diclofenic also known as Volatrol suppositories). Please bring spare pair of underwear.

You will be meet by the lithotripsy nurse on Antsy Ward who will go through some questions including medication and allergies. You will be asked to provide a urine sample and blood pressure will be noted plus medical history. Once this is complete you will need an x-ray to see the position of the stone each time you come.

It is important to eat and drink as normal – do not come starved. Please see advice sheet on page 5 of the downloadable PDF version of this information.

Please bring someone with you for your first treatment as we do not advise driving afterwards. After your first treatment most patients find that an escort is unnecessary. Once you scan is performed please return to Ansty ward.