Extracorporeal Lithotripsy for Kidney Stones
What does the Treatment for Extracorporeal Lithotripsy Involve?
Extracorporeal shockwave lithotripsy (ESWL) consists of fragmenting urinary stones with an energy-generating device.
The fragments are then eliminated from the body during urination.
This is an effective, non-invasive and low-risk treatment for lithiasis of the kidneys or ureter (tube connecting the kidney to the bladder).
This procedure successfully eliminates 74% of kidney stones and 88% of ureter stones. It therefore helps to avoid surgery.
However, ESWL is limited to some extent by the size, location and chemical composition of the stones. Stones up to 20 mm can be treated by ESWL, except those consisting of cystine (harder and more resistant to fragmentation) and those located in the kidney’s smaller chalices, whose maximum recommended size is 15 mm (as they are more difficult to eliminate).
Obesity (particularly the abdominal perimeter) also affects the success rate of extracorporeal lithotripsy, which is lower the larger the distance between the skin and the kidney.
What is the Extracorporeal Lithotripsy Procedure?
ESWL is performed with a device called a lithotriptor which applies shockwaves to urinary stones.
These shockwaves are created via electrohydraulic, piezoelectric or electromagnetic systems.
Shockwaves propagate through the skin and tissue between the skin and kidneys. They penetrate/traverse the patient’s body without damaging other tissue.
As stones have very different properties from water, the shockwaves fragment them.
The resulting fragments are then expelled naturally through the urine.
No anaesthetic is needed, but patients are generally medicated so that the procedure is more comfortable.
External lithotripsy takes about 30–60 minutes and if the stone is large, it is possible that various fragmentation sessions will be necessary. Sometimes, it is necessary to insert a catheter – a stent – in the urether between the kidney and bladder.
What are the Risks from External Lithotripsy?
The risks are low, but patients can witness blood in the urine and kidney pain.
Some fragments, when expelled, can cause pains similar to renal colic.
Contra-indications
The procedure is not recommended in the following situations:
- Pregnancy;
- Severe skeletal defects;
- Morbid obesity;
- Severe coagulation disorders;
- Untreated urinary infection;
- Aneurism or severe atherosclerotic disease of the renal artery and/or aorta;
- Presence of distal ureteral stenosis at the stone.
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What should you do after extracorporeal lithotripsy treatment?
In the following 24 hours, the patient should rest and must not drive or drink alcoholic beverages.
It is advised to drink more than two litres of water per day in the aim of expelling the fragments resulting from ESWL unless it causes intense pain. In this case, you should restrict liquids and contact the doctor who performed the treatment.
The patient must filter their urine in the following days to retrieve the fragments expelled for analysis.
If the patient develops fever, feels pain in the kidneys/side or has blood in their urine for more than 2 days after the procedure, they must consult their specialist.
Dr. José Santos Dias
Clinical Director of the Instituto da Próstata
- Bacherlor's Degree from the Faculty of Medicine at the University of Lisbon
- Specialist in Urology
- Fellow of the European Board of Urology
- Autor dos livros "Tudo o que sempre quis saber Sobre Próstata", "Urologia fundamental na Prática Clínica", "Urologia em 10 minutos","Casos Clínicos de Urologia" e "Protocolos de Urgência em Urologia"
FAQs about Extracorporeal Lithotripsy
Lithotripsy is indicated for what situations?
Does the stone disappear after ESWL?
How long does it take to recover?
What is the success rate?
References
- DIAS, José Santos. Urologia Fundamental: na prática clínica. Lisboa: Lidel - Edições Técnicas, Lda, 2010.
- Extracorporeal Shockwave Lithotripsy (ESWL) fo Stones - https://www.baus.org.uk/_userfiles/pages/files/Patients/Leaflets/ESWL.pdf
- Cálculos Ureterais, Ureterorenoscopia ou Litotrícia Extracorporal? - https://apurologia.pt/wp-content/uploads/2018/10/co54.pdf
- Lithotripsy for stones: What to expect - https://www.medicalnewstoday.com/articles/322355