US Market Report for Nephostromy Devices 2016 - MedCore
A nephrostomy may also be performed when there is a hole in the ureter or bladder and urine is leaking into the body, or as a diagnostic procedure to assess kidney function. Additional functions for nephrostomies include creating access for other endourological procedures including endoscopies, intracorporeal lithotripsy and the clearing of ureteropelvic junction obstructions (UPJ).
PCN procedures in this report focus on three main stages: Gaining access, the establishment of a nephrostomy tract and re-establishing a flow of urine to prevent kidney damage. The latter most stage is accomplished by placing a nephrostomy tube for drainage or a ureteral stent. To gain access, after the patient is anesthetized to numb the area for catheter insertion, a needle is inserted into the kidneys from the back. Several imaging techniques are employed, such as computerized tomography (CT), ultrasound or fluoroscopy, to help the surgeon guide the needle to the desired location. A fine guidewire is inserted through the needle, the needle is removed and a percutaneous access catheter is placed over the guidewire. Once access has been gained, the catheter is removed leaving the guidewire in place. Next, a 1.5 cm incision is made in the patient’s back that allows a lumen access catheter or wide caliber catheter to facilitate the placement of a second guidewire down the ureter. A working nephrostomy tract is then established using rigid or balloon dilators placed over the second guidewire. This allows a working sheath to be placed over the dilator into the collecting system in the renal pelvis. Once the working tract is established, other endoscopic procedures can be performed. For example intracorporeal lithotripsy probes can be advanced through an endoscope to break calculi (stones) in the kidney and the fragments removed. This process is known as percutaneous nephrolithotripsy (PCNL). Ureteral stents can be threaded into one or more ureters. This serves the function of providing a channel for urine to flow; small stones or stone fragments can more easily pass through stents if they were not removed during the PCNL procedure. At the conclusion of all activities, a nephrostomy tube is often installed and connected to a urinary collection bag outside the body for drainage.
The technique outlined above describes an antegrade approach to PCN and ureteral stent placement. A retrograde approach is performed through a cystourethroscopy using an endoscope passed through the urethra into the bladder. A guidewire is placed through an access catheter to allow the installation of a nephrostomy tube from the renal pelvis to an incision in the skin. Most ureteral stents are placed using a retrograde approach but in cases where this is not a viable option, an antegrade approach has proven effective. This chapter includes nephrostomy tubes placed using both techniques and ureteral stents positioned using an antegrade approach.
Patients are usually required to stay in the hospital up to several days after the procedure to ensure that the nephrostomy tube is functioning properly. The patient must take care of the nephrostomy tube and keep it dry. It constitutes the main part of the drainage system and should be treated with care to avoid infection. Nephrostomy tubes are typically changed every two to three months on an outpatient basis, while drainage bags should be changed once a week at minimum.Percutaneous nephrostomy (PCN) procedures create drainage of urine from the upper part of the urinary system to an external urinary collection bag. This is accomplished by puncturing the skin and inserting a catheter, also known as a nephrostomy drainage tube, into the renal pelvis. Under normal circumstances, urine travels between the kidneys and bladder through the ureters. When a blockage prevents this flow, ureteral stents are usually threaded into the ureter as a solution. In cases where this is not the best option, a nephrostomy tube can be used to maintain a passageway between the skin and renal pelvis to facilitate drainage. Without treatment, pressure would build within the urinary system and cause kidney damage. Blockage can result from tumors, kidney stones and pyonephrosis or the infection of the renal pelvis and collecting system.