Kidney Stone Removal - PCNL

What are kidney stones?

Kidney stones are hard deposits made of minerals and salts that form inside the kidneys. They can vary in size and cause symptoms such as severe pain, blood in the urine, and difficulty passing urine.

What is percutaneous nephrolithotomy (PCNL)?

Percutaneous nephrolithotomy (PCNL) is a surgical procedure used to remove kidney stones that are too large or complex to be passed naturally or treated with other methods. It is typically recommended for stones that are over 2cm in size or located in hard-to-reach areas within the kidney. This minimally invasive surgery is carried out under general anaesthesia and involves making a small incision in the back to access and remove the stones.

When is PCNL recommended?

PCNL is performed when kidney stones are too large for other less invasive treatments, such as shockwave lithotripsy (ESWL), or when previous treatments have been unsuccessful. Stones that are obstructing urine flow, causing pain, recurrent infections, or damage to the kidney, may also require PCNL. Other reasons to opt for PCNL include:

• Stones that have formed within complex areas of the kidney
• Multiple large stones in one or both kidneys
• Patients with anatomical abnormalities that make other treatments less effective
• Failed previous kidney stone treatments

This method is particularly effective for removing larger stones in a single session, making it a preferred choice in cases where other treatments may require multiple interventions.

Preparing for PCNL surgery

Before undergoing PCNL, patients will have a pre-operative consultation with a urologist to discuss the procedure and potential risks. Tests, such as blood work and imaging scans (ultrasound, CT, or X-rays), will be carried out to assess the size, number, and location of the stones.

Patients are usually asked to fast for several hours before surgery. It is important to inform the surgical team of any medications being taken, particularly blood thinners or anti-inflammatory drugs, as these may need to be stopped before the procedure to reduce the risk of bleeding.

Patients with underlying health conditions, such as heart disease or diabetes, may require additional assessments to ensure that they are fit for surgery.

What does the procedure involve?

When patients arrive at the hospital, they will meet a nurse, the anaesthetist and their surgeon. PCNL is carried out under general anaesthesia, which means the patient will be asleep during the procedure. The surgeon will make a small incision in the back and use imaging techniques, such as ultrasound or X-rays, to guide a tube (nephroscope) into the kidney. A small instrument is then used to break up the kidney stones into smaller fragments, which can be removed through the tube.

In some cases, a flexible tube called a stent may be placed in the ureter (the tube connecting the kidney to the bladder) to help urine drain properly after the procedure. A drainage tube, called a nephrostomy tube, may also be left in place temporarily to allow fluid to drain from the kidney.

The procedure usually takes between 1 and 3 hours, depending on the size and complexity of the stones.

What are the potential risks and complications?

As with any surgical procedure, PCNL carries some risks. While it is generally safe, potential complications include:

• Bleeding, which may require a blood transfusion
• Infection in the kidney or urinary tract
• Injury to surrounding organs, such as the bowel
• Persistent stone fragments, requiring further treatment
• Fluid leakage from the kidney
• Rarely, a loss of kidney function in the treated kidney

The surgeon will discuss these risks before the procedure.

After the procedure

Following PCNL, patients may need to stay in hospital for 1 to 2 days for monitoring and recovery. It is common to experience some discomfort or soreness in the area where the incision was made, as well as mild blood in the urine. Pain relief medication will be provided to manage any discomfort, and antibiotics may be prescribed to reduce the risk of infection.

Patients are advised to rest and avoid strenuous activities for at least 1 to 2 weeks after the surgery. Light activities, such as walking, are encouraged to aid recovery and prevent complications such as blood clots. It is important to stay hydrated to help flush out any remaining stone fragments.

A follow-up appointment will be scheduled to monitor recovery and assess if further treatment is required.

PCNL is effective in removing large kidney stones, and most patients experience significant relief from symptoms after the procedure. However, as kidney stones can recur, patients may be advised to make lifestyle or dietary changes to prevent future stone formation. This may include increasing water intake, reducing salt and oxalate-rich foods, or taking prescribed medications to help regulate mineral levels in the urine.