AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

The term nephrostomy refers to a passageway maintained by a tube, stent, or catheter that perforates the skin, passes through the body wall and renal parenchyma, and terminates in the renal pelvis or a calyx.

The nephrostomy has multiple functions but is used most frequently to provide urinary drainage when the ureter is obstructed and retrograde access is inadvisable or impossible. A nephrostomy can also be used to gain access to the upper urinary tract for various antegrade endourologic procedures, such as intracorporeal lithotripsy, chemical stone dissolution, antegrade radiologic studies of the ureter, and double-J stent placement.

Nephrostomy has several other functions, including the following:

• An avenue to remove or dissolve renal calculi
• To obtain direct access to the upper urinary tract for various endourologic procedures
• To diagnose ureteral obstruction, filling defects, and anomalies via antegrade radiography
• To deliver chemotherapeutic agents to the renal collecting system
• In tumors of the renal pelvis as prophylaxis after resection for local chemotherapy

An assessment of blood serum creatinine can be used to help evaluate obstruction and dilatation of the renal pelvis. Elevated levels indicate that the renal pelvis obstruction is related to kidney function. However, in all patients, nephrotoxic substances should be excluded as a source of renal failure. A renal scan is helpful in borderline cases (ie, when the renal pelvis is normal or minimally dilated and the creatinine level is slightly elevated).

To determine whether an obstruction is new or old, the patient's history is essential. Old films or sonograms can also be helpful. Most commonly, acute obstruction is caused by renal stones, whereas chronic obstruction is caused by renal or ureteral tumors and postoperative and radiation strictures of the ureter. A prior instance of renal failure was usually due to chronic obstruction.

The most dangerous cases of renal obstruction occur in patients who have urosepsis with renal obstruction and elevated creatinine levels. Fast renal access can be lifesaving in these patients. However, as with any procedure, the patient's general situation and prognosis must be evaluated prior to the procedure.

Tumors, such as sarcomas, ovarian tumors, and other retroperitoneal tumors (Ormond disease, intraperitoneal tumors), can compress the ureter. A nephrostomy may be required in all of these cases. Do not attempt retrograde access if a tumor spill or vascular lesion is likely to develop. Depending on the anatomical situation of the stricture, patients with ureteral strictures after vascular surgery, eg, for an aortofemoral bypass, should undergo nephrostomy placement.

Anatomical anomalies, such as an ureteropelvic junction (UPJ) obstruction, can create difficulty in retrograde access. Tumors or strictures that completely compress the ureter complicate or prevent retrograde access to the kidney. Passing a stent or guidewire antegrade rather than retrograde can be easier, as cystoscopy is not needed for antegrade access to the ureter.

Flexible antegrade pyeloureteroscopy can be performed through the nephrostomy when retrograde access to the ureter or kidney is not possible because of anatomic anomalies, tumors, or strictures.

History of the Procedure

In 1912, Hugh Hampton Young passed a pediatric cystoscope percutaneously into a massively hydronephrotic kidney. Willard Goodwin, MD, described percutaneous access and nephrostomies in 1955. In 1976, Fernström and Johansson performed a percutaneous nephrostomy specifically to remove a kidney stone.¹ In 1979, Smith and colleagues, from the University of Minnesota, began to remove stones in the renal pelvis and the ureter through percutaneous nephrostomy tracts (see Image 3). In 1981, Alken and colleagues, who were working in Germany, removed stones through matured percutaneous tracts.²

Problem

Nephrostomy involves creating an opening into the kidney to maintain temporary or permanent urinary drainage. The collecting system of the kidney is punctured percutaneously with a needle under fluoroscopic, ultrasonographic, or CT scan guidance. The needle is passed through the skin, subcutaneous tissue, external and internal muscle layers, and the renal parenchyma to reach the collecting system. When the needle has entered the renal collecting system, a guidewire is passed through the needle into the kidney and possibly down the ureter. Over the guidewire, various dilators can be used to establish and enlarge the nephrostomy tract, which is then maintained by a tube.

Alternatively, a nephrostomy tube can be placed during open surgery. In this procedure, a tube is placed into the renal pelvis, perforating the renal parenchyma and puncturing the flank musculature, subcutaneous tissues, and skin to create a direct passage between the renal collecting system and the external environment.

Anesthetic agents can be more hazardous in patients with overt renal shock. Therefore, performing the nephrostomy under local anesthesia is especially important when the procedure is potentially lifesaving.

Clinical

Symptoms of upper urinary tract obstruction can include flank or abdominal pain, nausea, vomiting, fever, or mild-to-severe urosepsis, including septic shock. Patients with calculi may be asymptomatic.

INDICATIONS

Section 3 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Percutaneous nephrostomy is occasionally essential, if not lifesaving, in the treatment of acute or chronic upper urinary tract obstruction. It is the first step in obtaining antegrade access to the kidney for various procedures. Specific indications for percutaneous nephrostomy include the following:

• Acute or chronic upper urinary tract obstruction in which access to the kidney is impossible from the lower urinary tract because of stones, infections, tumors, or anatomic anomalies, especially when a double-J stent cannot be placed through the ureter because of above-mentioned circumstances
• When a patient's creatinine level is rising above the reference range and the urine cannot be drained through the ureter
• Renal pelvis disorders (eg, UPJ obstruction, horseshoe kidneys, ureter duplex, ureter fissures, double renal collecting systems)  
• Hydronephrosis in renal transplant allografts: When dilatation of the renal pelvis affects kidney function to the extent that double-J stent placement is difficult or impossible, percutaneous nephrostomy may be an easier option.
• Treatment of staghorn calculi and large or lower-pole kidney stones (when a percutaneous nephrolithotomy [PCN] is likely to be followed because of the stone burden and an extracorporeal shockwave lithotripsy [ESWL] is less likely to be successful)
• Contraindications to ESWL (ie, size of patient): Most ESWL units have a weight limit of 140 kg (approximately 300 lb).
• Body habitus that prevents ESWL (eg, contractures): Disable patients occasionally cannot be positioned on an ESWL unit in a prone or supine position.
• Stones or tumors associated with distal obstruction or a foreign body that cannot be removed through the ureter (see Image 3)
• When rapid dilation of the nephrostomy tract is required (eg, when access is needed instantly for operative procedures within the renal collecting system [for stone removal or tumor ablation])
• Prolonged sequential dilatation: Gradually increasing the catheter size may be necessary when a nephrostomy tube is placed permanently for urine drainage in patients in whom a retrograde access to the kidney is impossible (eg, advanced metastatic tumors, loss of the total ureter, patients with a palliative nephrostomy tube whose cases are inoperable).

RELEVANT ANATOMY

Section 4 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

The kidneys are paired retroperitoneal organs below the diaphragm—below the liver on the right and below the spleen on the left. The kidney is located at the level of the 10th to the 12th ribs. The principal areas of the kidney include the renal cortex and medulla, renal pelvis, renal papillae, renal pyramids, ureter, renal artery, and renal vein (see Image 1). A fat capsule, the Gerota fascia, surrounds the kidney. The Brödel line also has historical interest. The minor renal calyces come together to the major renal calyces and make up the renal pelvis. The following organs supply blood to the kidney, in descending order: renal artery, interlobar artery, arcuate artery, intralobular artery, afferent arterioles, and glomerulus. All arterioles end arteries without communication, which is important for a possible embolization.

CONTRAINDICATIONS

Section 5 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

• Bleeding diathesis (eg, hemophilia, thrombocytopenia) and uncontrolled hypertension
• Anticoagulant use (eg, aspirin, heparin, warfarin)

WORKUP

Section 6 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Lab Studies

• Bleeding time, as indicated
• Prothrombin time
• Platelet count
• Activated partial thromboplastin time (aPTT)
• CBC count
• Urine culture
• Electrolyte assessment
• Creatinine assessment

Imaging Studies

• Any of the following studies can be used to assess patient anatomy:
• • Intravenous pyelography (IVP)
  • Abdominal CT scanning (see Images 4-5)
  • Renal ultrasonography

TREATMENT

Section 7 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Medical therapy

Evaluation can be conducted on an outpatient basis if the patient's medical condition permits. Inpatient studies and surgical treatment may be necessary in emergencies or in unstable patients.

• Medications
• • Most patients should receive broad-spectrum parenteral antibiotics.
  • If drugs are administered, the authors recommend cephalosporin or a combination of penicillin and aminoglycoside prior to the procedure, depending on the patient's allergies.
  • In pediatric patients, adjust antibiotics for age and weight.
  • Drug contraindications include corresponding drug allergies and urinary tract infection in an elective setting, hepatic failure, and renal failure.
• Pregnancy: During pregnancy, nephrostomy is limited to only selected individuals, such as those with symptomatic renal obstruction and an inability to access the kidney from the bladder.
• Consultations
• • Nephrologist, for possible dialysis
  • Oncologist, for prognosis and survival of patients with oncologic causes for urinary tract obstruction
  • Surgeon and gynecologist for urinary tract obstruction due to disorders in their respective fields

Preoperative details

• No special diet is required if surgery is performed under local anesthesia.
• The procedure can be performed under fluoroscopic or ultrasonographic guidance. A CT-guided nephrostomy or placement during open surgery is possible but is only rarely used.
• Perform the procedure in the operating room, the fluoroscopy suite, or the ultrasound room.
• Use lead glasses, a thyroid shield, and a lead apron when overhead radiography is used. Limit fluoroscopy time and cone down the radiation field.
• Several ultrasound transducers can be used (eg, 7.5-MHz transducers). Ultrasound has become the preferred guidance modality in the placement of a percutaneous nephrostomy. Opacifying the renal collecting system with intravenous or retrograde injection of iodinated contrast was once necessary to allow fluoroscopic visualization. The use of ultrasound reduces both the amount of radiation and the possible complications of intravenous administration. Furthermore, the real-time, multidimensional imaging reduces procedure time, allows visualization of adjacent structures, and reduces the possibility of iatrogenic trauma. Following placement of the nephrostomy needle, the procedure can be completed under ultrasonographic guidance; more commonly, the collecting system is opacified directly, and the procedure is completed under fluoroscopy.
• Even if the kidney has limited hydronephrosis and still needs nephrostomy, ultrasonography can be used to identify the renal collecting system.
• Proper selection of the appropriate calyx is vital in nephrostomy tube placement to allow access to various parts of the kidney. If the tube is placed too low, the ureter may be difficult to access; the ureter is easier to reach from an upper-pole calyx.
• Failed access is occasionally a problem. When nephrostomy placement not an emergency situation, wait a few hours (or even days) until the dilatation of the renal collecting system has increased to facilitate the puncturing of the collecting system.
• The nephrostomy tract usually matures within a few weeks; therefore, the nephrostomy remains open for hours to days after after the tube is removed following maturation. Whenever a tube is removed after a long period, place a pressure dressing to cover the skin and tract defect.

Intraoperative details

• Always obtain adequate visualization of the calices.
• Identify a posterior calyx for puncture that (1) provides access to the appropriate segment of the kidney for anticipated procedures and that (2) allows safe creation of a tract.
• Puncture the collecting system of the kidney with a needle below the 11th rib and, preferably, below the 12th rib, when feasible.
• Puncture the tip of a posterior calyx from a 20-30° posterior oblique approach to avoid major blood vessels (eg, renal vein, renal artery).
• The nephrostomy can be placed through any posterior calyx within the kidney.
• A lower-pole calyx is often selected for drainage because it is usually infracostal, thereby precluding a pneumothorax/hydrothorax complication (see Image 2).
• A supracostal puncture of the middle or upper portion of the kidney may be needed for stone or tumor removal.
• Use 5 mL of lidocaine (1%) for local anesthesia.
• Fluoroscopic guidance can be used for access, but some urologists and radiologists prefer ultrasonographic guidance (eg, with a 3-MHz or 5-MHz curvilinear transducer), especially until the nephrostomy needle passes into the collecting system.
• After entering the collecting system, withdraw the obturator of the needle. If urine flow is present, use 3-5 mL of contrast to check for proper placement.
• Advance a guidewire (eg, 0.035 in) into the collecting system.
• Remove the needle with the guidewire in place.
• Use a fascial incising needle or scalpel to cut the lumbodorsal fascia.
• The tract can be dilated with a plastic fascial dilating catheter passed over the guidewire (6F, 8F, and 10F catheters). Further dilation of the tract may be necessary if a percutaneous nephrolithotomy is planned.
• A nephrostomy catheter (8-14F) can be placed over the guidewire; affix it to the skin with a suture or plastic retainer. The catheter size depends on the intended purpose of the nephrostomy. Simple urine drainage can be achieved with an 8F catheter. If the collecting system is punctured for further procedures in the kidney (eg, tumor or stone removal), a larger catheter must be used (14-22F).
• The guidewire can be removed after the nephrostomy catheter has been checked fluoroscopically. If the tube leaks after placement, a larger tube may be used. However, most leakage resolves within a few hours. If the tube falls out, it can usually be replaced through the same tract (if the tract is matured). For freshly placed tubes, a new kidney puncture may be necessary.
• Use a pigtail with a lock; most nephrostomy catheters have a locking mechanism to prevent displacement.
• As indicated, send the aspirate from a kidney urine specimen for culture.
• Bleeding during nephrostomy placement may be enough to terminate the procedure; however, clamping the tube for 30-40 minutes and administering intravenous diuretics stops most venous bleeding. For arterial bleeding, perform angiography and consider embolization of the bleeding vessel.
• To preclude kinking, smoothly drape the tube as it exits the skin over a roll of gauze.
• Connect the nephrostomy catheter to a urine bag that can be strapped to the leg.

Postoperative details

After nephrostomy tube placement, most patients have bloody urine for several hours; this bleeding usually resolves spontaneously. The nephrostomy tube can be irrigated gently with 5 mL of sodium chloride 0.9%. Clots can be removed from the nephrostomy catheter. Observe for fever if the urine appears cloudy. If the hematuria does not resolve spontaneously, troubleshoot the nephrostomy as follows:

• If bleeding occurs from around the nephrostomy tube, an additional skin suture may resolve the bleeding.
• If bleeding occurs inside the nephrostomy tube, check the bleeding time and CBC count; then, consider arteriography and possible segmental embolization of the kidney in the interventional radiology department.

Postobstructive diuresis can occur with polyuria (for management, refer to Chronic Renal Failure and Acute Renal Failure). Regularly check blood pressure, blood count, and urine until they become stable. Conditions vary according to individual circumstances.

Follow-up

• Further inpatient care may require testing and surgical intervention, which may include nephrolithotomy or reconstructive surgery.
• Most patients can be discharged home the day of the procedure. Outpatient instructions focus on nephrostomy tube care (eg, change dressing daily, keep dressing dry and clean when showering, avoid submersion).
• Patients should avoid strenuous activity and sports until the nephrostomy tube is removed.

Inpatient and/or outpatient medications

• Prophylaxis with suppressive antibiotics is not recommended.
• Medications include antibiotics (eg, cephalosporin in cases of urinary tract infections) until infection is treated.
• Carefully monitor medication dose and adverse effects and treat infections only when symptomatic.

COMPLICATIONS

Section 8 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Common complications

• Perforation of the collecting system (<30%) typically resolves within 48 hours of nephrostomy tube placement, provided that drainage of the collecting system is established (via nephrostomy tube or ureteral catheter).
• Possible complications of the intercostal approach include pleural effusion, hydrothorax, and pneumothorax, possibly requiring chest tube placement (<13%).
• Acute bleeding requiring transfusion (<5%): Bleeding through the nephrostomy tube may require clamping the tube for 30 minutes to 2 hours and subsequent irrigation of the tube with sodium chloride 0.9% after enforced diuresis.
• Failed access (<5%): Reattempt access after the dilatation of the collecting system has increased in the course of hours or days.

Rare complications

• Periorgan injury, including bowel perforation, splenic injury, and liver injury (<1%): Extraperitoneal colon injury and duodenal injury can be managed conservatively with stenting of the urinary system and using the percutaneous tube as an enterostomy tube for 48 hours. Afterward, remove the enterostomy.
• Intraperitoneal injury that mandates open exploration (<1%)
• Infection leading to septicemia (<1%)
• Significant loss of functioning renal tissue (<1%)
• Delayed hemorrhage (<0.5%): The authors recommend that patients in whom the nephrostomy is doubtful or difficult are kept overnight.
• Emergency arterial embolization of the kidney (<0.5%) with uncontrollable arterial bleeding: Clamping the nephrostomy tube for a few hours stops most venous bleeding.
• Administration of antihistamines and steroids and use of nonionic or low-osmolar contrast media in cases of known allergic contrast reaction (<0.2%)
• Nephrectomy (<0.2%)
• Mortality (<0.05%)
• Patients with uncontrolled hypertension may develop perirenal hematoma or extensive renal hemorrhage. Use all efforts to control blood pressure.

FUTURE AND CONTROVERSIES

Section 9 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Medicolegal Pitfalls

• Failure to obtain informed consent on the indications and complications
• Removal of the nephrostomy tube
• • Fluoroscopic guidance may be necessary, especially to ensure proper drainage of urine through the ureter into the bladder prior to nephrostomy removal.
  • A thorough inspection of the catheter is necessary to ensure complete removal.
  • Retained fragments of a catheter predispose the patient to infection and calculi formation.

Acknowledgment

The authors thank E. Russel, MD, and H. Huson, MD, from the Department of Radiology and J. Posey, MD, from the Department of Urology of the University of Miami for their help.

MULTIMEDIA

Section 10 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

Media file 1:  Renal anatomy.
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Media file 2:  Positioning of nephrostomy tube into the lower pole of the kidney.
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Media file 3:  Outside appearance of a nephrostomy tube from the flank after stone removal.
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Media type:  Photo

Media file 4:  CT scan of bilateral hydronephrotic kidneys without intravenous contrast medium.
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Media type:  CT

Media file 5:  CT scan with dilated right ureter without intravenous contrast medium.
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Media type:  CT

REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Contraindications
• Workup
• Treatment
• Complications
• Future And Controversies
• Multimedia
• References

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16. Little B, Ho KJ, Gawley S, Young M. Use of nephrostomy tubes in ureteric obstruction from incurable malignancy. Int J Clin Pract. Apr 2003;57(3):180-1. [Medline].
17. Mariappan P, Smith G, Bariol SV, Moussa SA, Tolley DA. Stone and pelvic urine culture and sensitivity are better than bladder urine as predictors of urosepsis following percutaneous nephrolithotomy: a prospective clinical study. J Urol. May 2005;173(5):1610-4. [Medline].
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19. Picus D, Weyman PJ, Clayman RV, McClennan BL. Intercostal-space nephrostomy for percutaneous stone removal. AJR Am J Roentgenol. Aug 1986;147(2):393-7. [Medline].
20. Segura JW. Percutaneous management. In: Campbell's Urology. 7^th ed. Philadelphia, Pa: WB Saunders; 1992:2183-94.
21. Segura JW, Preminger GM, Assimos DG, Dretler SP, Kahn RI, Lingeman JE. Nephrolithiasis Clinical Guidelines Panel summary report on the management of staghorn calculi. The American Urological Association Nephrolithiasis Clinical Guidelines Panel. J Urol. Jun 1994;151(6):1648-51. [Medline].
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Article Last Updated: Dec 27, 2007