A nephrostomy tube is a specialized medical device designed to drain urine directly from the kidney. This thin, flexible catheter is placed through the skin of the back and into the renal pelvis, the funnel-shaped area inside the kidney where urine collects. Its primary function is to create a bypass around a blockage in the body’s normal urinary drainage system. The tube ensures that urine can exit the body safely, protecting the kidney from damaging back pressure.
The Mechanism of Urine Diversion
The kidney continuously produces urine, which normally flows down the ureter to the bladder before exiting the body. When a blockage occurs in the ureter, the urine backs up into the kidney’s collecting system. This accumulation of fluid causes the kidney to swell, a condition known as hydronephrosis.
The nephrostomy tube provides an immediate alternative path for drainage, alleviating this painful pressure. The tube is inserted directly into the renal pelvis. From there, the tube routes the urine through the layers of muscle and skin on the patient’s back, a process called percutaneous access. The external end of the catheter is connected to a secure collection bag worn outside the body. By diverting the flow, the tube immediately reduces the internal pressure caused by hydronephrosis, which helps preserve kidney function and reduces the risk of kidney infection.
Conditions That Necessitate the Tube
The placement of a nephrostomy tube is necessary anytime a blockage severely restricts or completely stops the flow of urine from the kidney. One of the most common causes for obstruction is large kidney stones that become lodged in the ureter, requiring immediate diversion to prevent permanent kidney damage.
Tumors are another frequent indication, especially cancers of the bladder, prostate, or reproductive organs that compress the ureter from the outside. Scar tissue, known as a stricture, can also narrow the ureter due to prior injury, surgery, or chronic inflammation. The tube is often placed temporarily to allow the patient to stabilize before a definitive procedure, such as surgery to remove a stone or treat a tumor.
In some situations, the nephrostomy tube may be required for long-term or indefinite use. This occurs when the underlying cause of the blockage, such as advanced, inoperable cancer or extensive scar tissue, cannot be fully resolved. For these patients, the tube provides a necessary permanent channel for drainage.
Managing Life with a Nephrostomy Tube
Daily care of the nephrostomy tube is centered on maintaining cleanliness at the insertion site and ensuring the system drains properly. The skin around the tube’s exit point should be cleaned daily with mild soap and water to prevent infection. A sterile dressing is applied over the site and typically changed every few days, or immediately if it becomes wet or soiled.
Patients must monitor the drainage bag output, ensuring it remains consistently below the level of the kidney to prevent backflow of urine. The bag should be emptied when it is about half to three-quarters full to avoid excess weight that can pull on the tube. While swimming or bathing in a tub is generally restricted, showering is usually permitted if the dressing is covered with waterproof material.
Troubleshooting involves recognizing signs of potential complications. If the tube stops draining or the patient experiences leaking around the site, this may indicate a clog or kink in the tubing. Simple measures include checking the tubing for bends or kinks, or sometimes flushing the tube with a sterile saline solution, as instructed by a healthcare provider. Should the tube accidentally fall out, contact a physician immediately, as the tract can close quickly. For long-term patients, the tube requires routine replacement every two to three months to prevent encrustation and maintain proper function.