Percutaneous Stone Removal-PCNL-

History

• The first description of percutaneous renal access was by Goodwin et al in 1955

• The first PCNL procedure performed by Fernstrom and Johannson 1976

Indications and contraindications

Indications– radiopaque or cystine renal stones with a diameter of

>20 mm– lower-pole stones, the procedure competes with

shock wave lithotripsy (SWL) and ureterorenoscopy – For stones <20 mm, SWL shows lower morbidity but

"mini-perc" is recommended as an alternative and has a higher stone-free rate.

The only absolute contraindications1. uncorrected coagulopathy

2. an untreated urinary infection.

Preoperative diagnostics

• A detailed medical history of the patient

• Radiologic definition of the stone size and the anatomy of the collecting system

• plain abdominal film of the kidney, ureters, and bladder (KUB) in combination with intravenous urography

• Ultrasound • computed tomography (CT) scans

• Laboratory • coagulation parameters and electrolytes• urine culture - is strongly recommended

• prone position - The traditional way of performing PCNL, as described by Alken et al

• supine position - The new way of performing PCNL by Valdivia (combined approach with simultaneous ureteroscopy is easy to perform)

Positioning of the patient

Anesthesia

1. general anesthesia - mostly

2. spinal-epidural anesthesia – very good report cost efficacy and safety

3. local anesthesia - seems to be a feasible in selected group of patients

Renal access

Renal access is divided into two main parts: – puncture of the collecting system – dilation of the tract.

• most urologists from EU puncture the collecting system themselves (90.1%)

• in the US - 11% of urologists obtained the renal access on their own

Puncture of the collecting system Access type

– Radiological - radiographic guidance alone the “bull's eye” technique and the triangulation technique

The dorsal calyx of the lower pole is the usually acces site

Supracostal access to an upper calyx due to stone location in the upper pole.

10th-rib supracostal approach is prohibitive - 63% risk of puncturing the lung

After puncture will are passing the papilla in the long axis of the target calyx avoids contact with large vessels

Ultrasonographical - ultrasonography-guided access in experienced centers, is safe and efficient,

The dilation of the tract tehnique

• metallic telescope dilator system and placement of a metallic sheath – Alken

• serial plastic dilators and then placement of a plastic sheath (Amplatz sheath)

• tract dilation using a balloon Clayman

Disintegration

• the stones are usually disintegrated mechanically with a lithoclast device or a holmium laser.

• Ultrasonic disintegration • Fragments can usually be flushed out through the

access sheath or recovered with a stone basket or with special forceps

Operation time seems to be dependent on stone size.

Standard PCNL - a nephrostomy tube is inserted after the PCNL with the intention of both draining the urine and tamponading the access tract

Tubeless PCNL – intern ureteral drainage

Totally tubeless PCNL - without any drainage

Complications

Organ injury • Colonic injury < 1 %• Lung injury• Spleenic and hepatic injury

Bleeding complications • In most, it is limited • selective arteriography with

embolisation is feasible 1%• Nephrectomy 0.2%

Infectious complications 30% • Fever • Sepsis