A nephrostomy tube is a small, flexible catheter inserted into the renal pelvis, the part of the kidney that collects urine. This device is necessary when the normal pathway for urine drainage—the ureter—is blocked, often due to kidney stones, tumors, or injury. The tube reroutes urine directly from the kidney to an external drainage bag, relieving pressure and preventing damage to the organ. Whether the entry point qualifies as a traditional surgical wound depends on the unique method of its placement.
The Nephrostomy Procedure
Placement of a nephrostomy tube is typically a minimally invasive procedure known as a percutaneous nephrostomy, meaning “through the skin.” This distinguishes it from conventional open surgery requiring a large incision. The procedure is performed by an interventional radiologist or a urologist, who uses real-time imaging guidance like fluoroscopy or ultrasound to visualize the kidney.
After administering a local anesthetic, a fine needle is guided into the kidney’s collecting system. A guide wire is then threaded through the needle. The tissue tract is gently widened, or dilated, over the guide wire until it is large enough to accommodate the tube. The tube is then secured in place, usually with a stitch or fixation device at the skin level. This technique creates a small, circular opening that follows the path of the tube, avoiding the extensive cutting associated with a traditional surgical opening.
Classifying the Tube Entry Site
The entry site for a nephrostomy tube is functionally different from a standard surgical incision, which is a linear cut closed with sutures or staples. Because the tube is placed using a needle puncture and dilation, the resulting opening is classified as a tract or stoma. A stoma is an artificial opening created on the body’s surface for drainage, which is maintained by the presence of the tube itself.
The opening is not intended to heal immediately; the tube must maintain the patency of the tract to drain urine. Therefore, the site is managed less like a healing, sutured wound and more like a drain exit site requiring meticulous infection control. The tissues surrounding the tube form a continuous passageway from the skin surface to the kidney, influencing subsequent care protocols.
Practical Care and Healing Expectations
The unique nature of the nephrostomy tract requires specific practical care. Maintaining a sterile environment is paramount because the tract provides a direct, continuous path for external bacteria to reach the kidney. The dressing surrounding the tube exit site must be kept clean, dry, and secure, and should be changed regularly, typically once a week or immediately if soiled or wet.
Patients must inspect the area daily for signs of complication, such as new redness, swelling, increased pain, or the presence of pus or foul-smelling discharge. The drainage bag must always be kept below the level of the kidney to prevent the backflow of urine, which could introduce bacteria into the tract. Any leakage of urine around the tube, known as peristomal leakage, requires prompt attention as moisture can break down the skin and increase infection risk.
When the tube is ready for removal, the physician deflates any locking mechanism and gently withdraws the catheter. Because the tract is small and was maintained solely by the tube’s presence, healing is usually fast. The puncture site often closes completely within 24 to 48 hours after removal. Patients are instructed to keep the site covered with a small dressing and avoid strenuous activity, tub bathing, or swimming until the skin has fully sealed.