Extracorporeal shock wave lithotripsy

Introduction
Extracorporeal Shock Wave Lithotripsy (ESWL) uses the principle of shock waves. Shock waves emitted by a lithotripter are focused and transmitted through the skin via contact with the machine to the stones, shattering them. The broken-down stones are then naturally expelled through urine.
Shockwave lithotripsy is one of the treatments for kidney stones and ureteric stones. Other treatment options include: conservative management, percutaneous nephrolithotomy, ureteroscopy with lithotripsy, and open or laparoscopic surgery. Other auxiliary procedures may be required, including insertion and removal of a ureteric stent.

Indications
Kidney stones and ureteral stones

Treatment process

1. No general or local anaesthetic required
2. The patient lies prone or supine on the lithotripter table.
3. The small shockwave generator is attached closely to the patient's waist or abdomen.
4. The patient needs to undergo an X-ray scan to determine the location of the stones.
5. During treatment, patients may experience pain, and doctors will prescribe painkillers to alleviate their pain.
6. The lithotripsy procedure takes about an hour.

Potential dangers or complications

1. Haematuria, difficulty urinating and renal colic (common)
2. Damage to the urinary system – including renal rupture and renal haematoma, which may require a blood transfusion (<1%), radiotherapy or surgical treatment, including nephrectomy
3. Cannot determine stone location via X-ray
4. Obstruction of the ureter due to incomplete fragmentation and clearance of kidney stones, necessitating re-treatment and supplementary treatment, such as the insertion of a ureteral stent.
5. Irregular heartbeat, radiation risk, side effects of sedatives and drugs
6. Damage to organs near the kidneys, such as the lungs, liver, pancreas, spleen, intestines, as well as the lungs, pelvic organs, skin and soft tissues
7. Urinary tract infection, kidney inflammation, sepsis
8. Stone residue, stone recurrence
9. Loss of kidney function, kidney failure
10. Death (rare)

The above does not list all dangers or complications, including rarer ones.

Pre-treatment preparation

1. Patients will undergo a physical examination, blood tests, urine tests, X-rays, and an electrocardiogram before surgery. Contraindications for this surgery include aortic aneurysm, untreated hypertension, and active urinary tract infection. Other specialist consultations will be arranged if necessary. Patients must stop taking antiplatelet medications (such as aspirin) or blood thinners as instructed by their doctor before the start of the operation.
2. If you have a pacemaker or implantable cardioverter-defibrillator (ICD) implanted in your body, please inform your doctor to arrange a consultation with a cardiac specialist and take precautionary measures.
3. Pregnant women of childbearing age should undergo a pregnancy test, as X-rays can cause serious harm to the fetus.
4. You will need to eat a low-fibre meal and take a laxative the evening before your treatment.
5. No food or drink for 4 hours before treatment.
6. You may need to receive an intravenous infusion (drip) or medication before treatment.
7. In the event of any unforeseen circumstances, treatment will be cancelled and further arrangements will be made.

Post-treatment situation

1. Haematuria, painful urination, difficulty urinating, and renal colic (common).
2. Bruising may occur on the skin at the treatment site.
3. Blood in the urine or painful urination may occur within one week of treatment, with mild pain in the lower back and abdomen. Symptoms usually disappear within one to two weeks.
4. It is recommended that patients drink plenty of water for several days after treatment to help expel the shattered stones through the urinary tract. Some patients may experience mild pain during urination or varying degrees of blood in their urine.

Post-discharge instructions

1. It is normal to experience frequent urination, difficulty controlling the urge to urinate, or slight blood in the urine after treatment.
2. Patients may walk or use the stairs, but should avoid excessive exertion or lifting heavy objects.
3. Drink as much water as you can.
4. Please attend your specialist outpatient clinic appointment on the specified date and time for follow-up to monitor your progress after treatment.

Notes
This leaflet provides only basic information about the surgery. It is not exhaustive regarding potential risks or complications, and the actual degree of risk varies between patients. Please consult your doctor if you have any questions.

Source: https://www.ekg.org.hk/pilic/public/surgery_pilic/urosurg_extracorporealshockwavelithotripsy_0195_chi.pdf