Percutaneous Nephrolithotomy (P.C.N.L.)

Technological revolution has made open surgery for the removal of kidney stones uncommon. Percutaneous surgery uses x-ray imaging, guide wires and tubes to remove kidney stones. Percutaneous means through the skin.Nephrolithotomy is a surgical cut into the kidney. P.C.N.L. is performed to remove stones that are causing a blockage or to treat ongoing symptoms such as pain and recurrent infection. Recovery time after surgery is much shorter.

Preoperative Workup

CONSENT

Signing the consent form implies your permission for your surgery to go ahead. Before you sign the consent form it is important that you understand the risks and effects of the operation and anesthesia. These will be discussed with you by your doctor. Should you have any questions all of them should be clarified in the OPD with your Doctor before you proceed to sign the consent form. With percutaneous surgery there is a small chance that you may require a blood transfusion either during or after surgery.

ANESTHESIA INSTRUCTIONS

You will NOT be allowed to eat or drink anything for at least six hours before your surgery. This includes water too.

This type of surgery requires a general anesthesia which means you will be asleep throughout the operation and remember nothing of it. Anesthesia questions should be answered and discussed with anesthetist at the time of PAC.

You must not drive any vehicle or operate any machinery for 24 hours after having anesthesia. You will have to arrange for someone to drive you home if you go home within 24 hours of your surgery.

OPERATION INSTRUCTIONS

On admission you will be informed of an approximate operation time and prepared for theatre. You may also be instructed about special deep breathing and leg exercises that you should do after surgery.

A shave of the surgical site may be required. This is usually done just prior to going to theatre.You may be given some tablets on the night before theatre. These are charted by your anesthetist and may include tablets for tension, nausea and pain prevention.

You will be escorted to the theatre, where you will be transferred to the theatre table. Anesthesia staff will then insert a drip in your arm and will attach various monitoring devices. Once under G.A surgery will begin. When the operation is completed you will go to the recovery room for 2-4 hours, where you will be kept under observation until you are ready to be transferred to the ward.

 

Surgery

WHAT DOES THE OPERATION INVOLVE?

Once you are under general anaesthesia a ureteric catheter is kept into the ureter cystoscopically. Patient is made prone & a thin guide wire is inserted through the back, into the kidney with the aid of x-ray imaging and radio-opaque contrast to ensure the placement is exact.

Once the guide wire is in position, a 1- 1.5 cm skin incision is made and the tract dilated upto 8 mm to 1 cm diameter. A camera is passed through the tract and its images are conveyed to a television screen. When the stone is in view it is blasted with ultrasound or shock waves or laser pulverized into smaller pieces that can then be removed. Once all of the pieces of stone have been removed, a nephrostomy tube, is placed through the tract and it is stitched into place. The Urologist may decideintraoperatively not to place a Nephrostomy Tube (Tubeless PCNL) on a case to case basis. This is connected to a drainage bag that drains any urine, blood or stone fragments from the kidney. A double J stent (a thin flexible tube inside your ureter) is placed to allow small stone fragments to pass alongside the stent without blocking off the flow of urine and causing pain. A Foleys catheter is also placed to drain your urine. The catheter is held in place inside the bladder by a small inflated balloon so it can’t slip out. Depending on the location and number of stones, surgery can take anywhere from 1 to 4 hours to complete and usually involves a one to two days hospital stay. Complicated stones may need development of more than one tracts and placement of more than one nephrostomy tubes.

WHAT RISKS ARE INVOLVED WITH SURGERY?

In case of large stone load or complex stones repeat PCNL may be needed before a patient is completely stone free. With larger stones in upper ureter, access can be more difficult and there is a risk of injury to the ureter during the operation.

This can cause scarring of the ureter, which can narrow the channel. This is known as a ureteral stricture, it is uncommon but if it occurs it is treated with surgery which opens the narrowing (endourological/robotic/laparoscopic management)

There is always some bleeding involved with surgery, however if a main artery is involved, large amounts of blood can be lost and angiographic embolisation may be needed to control bleeding which entails extra expenses & increases hospital stay by another 1-2 days.

The upper part of the kidney sits close to the lungs and on the right side the liver and on the left the spleen. If access to the stone is only possible using a high approach to the upper kidney, the risks of this would be weighed up with the benefits of the percutaneous approach and surgery would only proceed if the urologist felt it were in the best interest of the patient. Using a higher approach increases the risk of puncturing any organs close to the kidney. Puncture of a lung may cause the lung to deflate and a tube may need to be inserted for 2-4 days to re-inflate the lung. All of these complications are rare and majority of patients are stone free after surgery and have a speedy recovery. Rarely some stone fragments can be left behind if very high puncture is required keeping the safety of the patient paramount.

Post Operative Management

AFTER SURGERY

Your blood pressure and pulse are checked regularly. Your wound will be checked for any bleeding and the urine output from your nephrostomy tube and catheter will be monitored closely. You will have a drip in your arm to make sure you receive adequate fluids. This will be removed once you are drinking normally. You can usually drink when your return to the ward and you may eat once you are tolerating fluids.

You may have a P.C.A pump attached to your drip. P.C.A stands for Patient Controlled Analgesia, a machine that delivers pain relief through your drip on your command. You will be instructed on the use of the P.C.A. should you have one. You will be given regular pain relieving tablets to keep you comfortable so you may not need a P.C.A pump.

At all times, your nurse is there to help you, please ring your bell if you need assistance and your nurse is not nearby.

ON THE DAY FOLLOWING PCNL:

The nephrostomy tube is removed next morning after confirming there are no residual stones on X – Ray KUB. The nephrostomy maybe kept for a day extra if it’s asupracostal high puncture for better healing. You may have some urinary leak from the wound site after the nephrostomy has been removed but it usually settles down on its own. If the wound stays dry for next 24 hours the Foley’s catheter is removed.

You may have a burning sensation when passing urine after the catheter is removed. This if required can be relieved with medication or increased intake of water.

 

Discharge Instructions

GOING HOME

Once your catheter and nephrostomy have been removed and you are eating and drinking and passing urine normally, you will be discharged. If all of the stone fragments could not be removed and further management is required, you would be advised accordingly for needful management.

Before leaving the ward you will be given a discharge summary which contains summary of the procedure along with instructions for further course of action.

If you have a double J stent, this may be removed under local anesthesia, after X-ray KUB to check for stone clearance. A thin flexible cystoscope is passed up the urethra into the bladder & the stent grasped & removed. Double J stent removal requires admission in Daycare for 4-6 hrs.

ONCE HOME

The internal healing after surgery takes 4-6 weeks. During this time you should avoid any heavy lifting, straining or strenuous activity. Apart from strenuous activities you will be able to continue with your normal daily routines, as per your comfort level.

You should wash your wound with water only. No soap or powder is to be used directly on your wound until it is healed completely. Your wound would usually be dry within 48 hours of surgery, prior to this you may need to place a small plaster over it to stop any slight ooze marking your clothing.

Avoid constipated by eating high fiber diet. If you have problems with constipation you may require a stool softener.

Contact your own doctor if

• Your wound becomes red, hot, swollen and painful or continues to discharge.
• Your urine becomes cloudy, offensive smelling or you have any other signs of a urine infection including painful urination.
• You have any concerns at all.

Follow-up

Patients who have formed stones have a tendency to form them again. They should keep their water intake more than 3-3.5 ltrs per day. It is also advised that they should follow themselves up with renal function tests and imaging like an ultrasound KUB after surgery as advised by their doctor.

HOW DO STONES FORM AND WHAT CAN I DO ABOUT STOPPING THEM FROM FORMING AGAIN?

A stone begins as a tiny particle that is left behind when the urine flows out of the kidney. Over time, particles bond together and the stone becomes larger. The majority of stones are eventually carried out of the kidney into the ureter and down to the bladder; however some stones remain in place within the kidney and continue to grow. When these stones start to block the flow of urine, they can cause pain and infection. Stone formers are more likely to develop another stone compared to someone who has never had a stone before. Stones maybe formed by a metabolic imbalance which may need some additional testing of the blood & occasionally urine to rule out medically treatable causes. The best way to prevent further stones forming is to drink more water. The best fluid to drink is water, however, any fluid is fine, but tea and coffee should be restricted. Your daily fluid intake should be between 2.5-3 liters, or more in the summer months. You will know when you are drinking enough by the color of your urine, which should stay a very pale yellow to clear color. If stones continue to reform frequently and there is a proven metabolic problem certain diet restrictions and medication may be needed to help prevent further formation of stones.

If you are worried about anything before or after your surgery, or if you have any further questions or would like more information, please ask your urologist.