Why is Percutaneous Nephrolithotomy (PCNL) necessary?

Whilst the majority of small kidney stones can be treated using the shock wave machine (Lithotriptor), large stones are not suitable for this form of treatments and require removal by means of an operating telescope (PCNL). 

There are other situations where relatively small kidney stones may require surgical treatment rather than Lithotripsy, for instance if the stone is difficult to see on x-ray or if it is particularly hard.  Even if large kidney stones do not cause symptoms they still require treatment, as we know from experience that left untreated patients eventually run into difficulties.

To help the urologist to decide what is the best treatment for your kidney stones, e-rays will have been taken and these will have been reviewed by a team of urologists and radiologists (x-ray doctors).  Your case will have been discussed to ensure there is general agreement that surgery is the correct form of treatment for your stone(s).

What preparation is necessary?

On the day before PCNL an up to date x-ray is taken to make sure the stone has not increased in size or moved.  Routine urine and blood tests will have been taken from the clinic to ensure the kidneys are functioning normally and that there is no infection.

You need to be ready for a 5 day stay in hospital, although you may be able to leave after 4 days.  You should anticipate a two week period of convalescence at home before you are able to get back to a full range of normal activities. 

If you are taking blood thinning medication such as warfarin this will need to be discontinued prior to surgery. 

On the morning of the operation you change into a gown and you will be pushed to the operating room on a trolley.  The anaesthetist will then put you to sleep, usually by an injection in the back of your hand.

The first part of the operation is to give you an anaesthetic (put you to sleep) so that you will not be aware of anything whilst the operation is being performed.  The first step of the operation is to examine the bladder with a telescope and to pass a fine tube up the pipe with connects the kidney to the bladder (ureter).

A dye called contrast is then passed up the tube so that the kidney can be visualised using x-rays.  This part of the procedure has been performed whilst you are positioned on your back.  You will then be rolled over so that you are lying on your front.  One of the doctors will then place a very fine needle through the skin into the kidney and under x-ray guidance a track will then be stretched up around the needle so that an operating telescope can be introduced into the kidney.  Once the stone has been identified it will be broken up and removed. 

The aim is to remove all stone fragments in one treatment, although sometimes this is not possible.  In this situation you may require further key-hole surgery or shock wave treatment (Lithotripsy).  At the end of the procedure a drain is left between the kidney and the skin and this is removed after 48 hours.

A catheter tube is left in the bladder and this is usually removed the morning following surgery.  Occasionally if the stone is found to be very infected the kidney is left to drain through for a period of time before proceeding with definitive surgery to remove the stone.

What will happen after the operation ?

You will wake up in the recovery area in your bed and when the nurses there are happy with your condition you will be transferred back to the ward.  You will have a catheter tube draining the bladder and tube draining the kidney.  You will fee “groggy” during the first night after the operation and there may be some pain, which should be relieved by asking the nurse for a painkiller. 

The catheter tube in the bladder will be removed on the day following surgery.  The kidney drain has two parts, an inner and outer part.  The outer part is usually removed on the day following surgery and the inner part removed on the second day. 

All being well you should be ready for discharge on the 3rd day following your surgery. 

An x-ray will be taken on the morning after surgery to look for any remaining stone fragments.

What problems may occur ?

PCNL is performed commonly on the urology unit and complications are unusual.  The most common problem is one of infection and you will routinely receive antibiotics to try and prevent this happening. 

Occasionally the kidney puncture can result in bleeding and approximately 5% of patients will require a blood transfusion. 

Very occasionally bleeding can be significant and in this situation the bleeding vessel is blocked off by one of our Interventional Radiologist using an x-ray technique called embolisation. 

If it is not possible to achieve complete stone clearance with one operation you may require further treatment with either repeated surgery or shock-wave treatment (lithotripsy).

How can I prevent stones reforming ?

The best general advice is to maintain dilute urine and this is easy by drinking lots of water, especially during warm weather.  You would aim to produce no less than 2 litres of urine per day. 

When we know what your stone is made up of we may be able to give you more specific advice regarding medical treatment to prevent stone recurrence.  If you have a history of stone formation then you may require more detailed tests such as 24 hour urine collection.  Your doctors will be able to advise you regarding this.

How can other questions be answered?

If you are concerned about any aspect of your operation you can make an appointment to speak to your consultant in the Out-Patient Clinic by contacting the Secretary on (0191) 233 6161.  When you are admitted for surgery you will be seen by your surgeon who will be able to answer any questions you have.   

The nurses on the ward have a lot of experience of nursing patients with stone disease and would be happy to answer any specific questions.

A final word

We have a large experience of PCNLs here at Freeman Hospital and are proud of our success rates.  This type of operation along with shock wave Lithotripsy has revolutionised the treatment of kidney stones.

As with all surgical procedures there is always a small risk of complications but if these do occur the hospital has all the facilities and expertise on site to deal with them.  The majority of patients have a trouble free stay and make a  quick recovery.