endo = through a scope (without an incision on the body) pyelo = the pelvis of the kidney or the center part of the kidney where the ureter begins tomy = from "tome" meaning to cut
After urine is produced by the kidney, it drains into the center of the kidney called the collecting system. The individual passageways of the collecting system come together to form one large central area call the renal pelvis. The renal pelvis subsequently funnels urine into the ureter. The ureter is a thin tube that connects each kidney with your urinary bladder.
When there is a problem within the ureter or kidney, we can frequently approach it with a small telescope that is inserted through the urethra (tube through which you urinate), into your bladder, and then into the ureter. The scope can be advanced all the way into the renal pelvis or its branches. Another approach to the renal pelvis or ureter is through a small hole made in the back in the region of the kidney. This is referred to as percutaneous (through the skin)access to the kidney or ureter. When we enter the ureter from below (through the urethra), this is referred to as a retrograde procedure. If the approach is through the back, this is referred to as an antegrade procedure. These terms will be used below.
When there is a blockage at the junction where the
renal pelvis meets the actual ureters, we call this a
uretero pelvic junction obstruction (UPJ obstruction).
The exact cause of a UPJ obstruction is unknown but
may be due to:
a blood vessel crossing this area and consequently compressing the region a true area of scar tissue an area of the ureter that is missing muscle components in its wall and therefore does not have proper peristalsis (contracting motion to move urine along)
*People are usually born with UPJ obstructions, but may also develop them later in life. Notall UPJ obstructions require correction. Sometimes they are discovered incidentally (while evaluating another problem) in older adults who have had no symptoms, and in whom the kidney has suffered minimal damage as a result. Alternatively, if a patient is found to have a very minimally or non-functioning kidney as a result of an undiscovered UPJ obstruction, then surgical correction may not be necessary. In other words, there may be no benefit to the procedure. Factors that dictate a need for treatment include:
- pain or other symptoms due to the presence of obstruction
- deterioration of a functioning kidney due to the obstruction
- formation of stones or infections due to impaired urine flow
- a younger patient in which there is greater uncertainty as to whether the kidney will ultimately lose function
When an incision is made in a UPJ obstruction through a scope, this is referred to as anendopyelotomy. After an endopyelotomy, it is usually necessary to leave a stent (plastic drainage tube) in the ureter for weeks to allow adequate drainage and resolution of inflammation of the tract. This tube is not visible on the outside of the body as one end is in the kidney, and the other in the bladder. The stent can be easily removed in the office without anesthesia. The amount of time that the stent remains in will depend on your particular situation.
There is no particular preparation for this procedure. As with any procedure in which anesthesia is administered, you will be asked not to eat or drink anything after midnight on the evening prior to your surgery. You may brush your teeth in the morning but not swallow the water. If you are on medications that must be taken, you will have discussed this with us and/or the anesthesiologist and instructions will have been given to you. The procedure will not be performed if you are currently taking, or have recently taken any medication that may interfere with your ability to clot your blood ("blood thinners, aspirin, anti-inflammatory medicines, etc..."). The most common of these medications are aspirin and all related pain relievers or anti-inflammatory compounds (whether prescription or over-the-counter). Please refer to the attached list and tell us if you took any of these within the past 10 days. If your new medication is not on the list, alert us immediately so that we may ensure optimal procedure safety. We will have reviewed all of your current medications with you during the pre-operative/pre-procedure consultation. You are obligated to inform us if anything has changed (medication or otherwise) since your previous visit.
To review the basics of what we discussed in the office: The actual procedure usually takes less than one hour depending on the approach (retrograde-usually shorter vs. antegrade-usually longer) as well as on the individual's anatomy. Both procedures are usually performed under general anesthesia (complete sleep). Your surgeon will recommend the approach based on their preference as well as your particular circumstances.
For the retrograde approach, you will be placed lying down on your back with your legs gently elevated in holsters (called stirrups). The procedure may be done under direct vision or by x-ray guidance. When done with direct vision, a small scope is advanced all the way up the ureter to the point of obstruction. A laser or other modality is then used to incise (cut) the scar. In certain instances, the area may be further dilated by inflating a small balloon in the area of the incision. When we are satisfied with the result, a stent is placed in the ureter to allow healing for weeks. When performed with x-ray guidance, the scope is advanced only into the bladder. A special type of catheter is then inserted through the scope and to the level of the scar with x-ray guidance. The scar is cut with an electric wire and further spread with a balloon. Once again, a stent is placed and left for weeks.
For the antegrade approach, you will be placed on the table prone (lying on your stomach face down). Once asleep, you will be positioned with proper cushions and supports. A needle is used to access the kidney through the back. We dilate (spread open) the access tract up to the size of a nickel until we can fit our nephroscope (scope that goes into the kidney) inside. The scope is advanced to the level of the obstruction. Just as in the direct vision retrograde approach, a knife blade, laser or other instrument is used to incise the scar. In certain instances again, the area may be dilated by inflating a small balloon in the area of the incision.
A stent is left in the ureter. In the antegrade approach, a nephrostomy tube (drainage tube from the kidney out to the back) is often left for a few days as well.
After the retrograde procedure, you will be in the recovery room until you are ready to be discharged. It is uncommon for a patient to be admitted to the hospital afterward, but certain circumstances could make admission necessary.
After the antegrade procedure, you may be admitted overnight for observation. As mentioned, there will be a nephrostomy tube and a stent. The nephrostomy tube is easily removed the following morning, and the area is covered with a sterile dressing. It is quite common to have minor urine leakage from the hole in the back for a few days. It usually stops on its own, but may require dressing changes.
Regardless of the approach you may have some discomfort when you first urinate. You may also feel a sense of urgency to urinate even if you have just emptied your bladder. Typically, these symptoms disappear within one to two days, but may persist as a result of the presence of the stent in the ureter. Although the stent is soft plastic, any degree of sensation from its presence is possible. Some patients have no feeling, while on the other extreme, some have very bothersome symptoms. The symptoms can be any one or a combination of back or groin discomfort, urinary frequency, urgency or burning. The symptoms may last for a few days orpersist for the duration of the presence of the stent. Most patients, however, have very mild symptoms that are tolerable.
Patients may have no blood in the urine, mild blood, or even what appears to be a significant amount of blood or small clots. The blood usually disappears within a day or two. As a result of the instrumentation, it is also possible to have discomfort in the back or groin region. This, too, will gradually disappear.
Expectations of Outcome
While our intent is to adequately open the UPJ obstruction, this is not always possible. In the retrograde approach, there are instances in which the scope or catheter cannot be passed safely into the ureter. Common reasons include a very large prostate or scarring at another location in the ureter (i.e. from a history of stones or other procedures). In this case, we might try to just pass a stent to temporarily alleviate the UPJ obstruction. The next step would be discussed in a follow-up consultation. In the antegrade approach we may not be able to gain proper access to the renal pelvis as well.
As previously mentioned, the stent will remain in the ureter for a few weeks. It is easily removed in the office.
Success of these procedures varies. Overall, the antegrade approach may have a slightly higher success rate, but is more invasive.
Despite a properly performed procedure, an obstruction can persist or recur at any point in time. It is therefore imperative that you be followed up at regular intervals.
Possible Complications of the Procedure ALL surgical procedures, regardless of complexity or time, can be associated with unforeseen problems. They may be immediate or even quite delayed in presentation. While we have discussed these and possibly others in your consultation, we would like you to have a list so that you may ask questions if you are still concerned. It is important that every patient be made aware of all possible outcomes which may include, but are not limited to:
- Urinary Tract Infection or Urosepsis: Although we may give you antibiotics, it is still possible for you to get an infection. It may be a simple bladder infection that presents with symptoms of burning urination, urinary frequency and a strong urge to urinate. This will usually resolve with a few days of antibiotics. If the infection enters the bloodstream, you may feel very ill. This type of infection can present with both urinary symptoms and any combination of the following: fevers, shaking chills, weakness or dizziness, nausea and vomiting. You may require a short hospitalization for intravenous antibiotics, fluids, and observation. This problem is more common in diabetics, patients on long-term steroids, or patients with any disorder of the immune system. We also see infections more commonly in patients who already have a stent in place prior to this procedure.
*If you have symptoms suggesting any of the above after your discharge from the hospital, you must contact us immediately or go to the nearest emergency room.
- Urinoma: Because the incision in the ureter is made through the entire wall, some urine may leak across the incision. This urinoma (collection of urine) is rarely of any consequence. If the leakage persists or becomes large, it can cause discomfort by placing pressure on nearby structures. If a stent is in good position and therefore providing good drainage down to the bladder, the leak will usually stop and the urinoma will disappear with time. If persistent or troublesome, a minimally invasive procedure to place a drain outside the ureter or kidney may be necessary.
- Blood Loss/Transfusion: Despite our understanding of the anatomy (specifically the location blood vessels), it is possible to cause an injury to a "crossing vessel" (one that courses across the area of the renal pelvis). Although its position is usually predictable(and may often be seen when the procedure is done under direct vision), there are instances in which the vessel is in an unusual position. If a vessel is cut, bleeding can be significant. The blood can impair drainage of the kidney by clotting within the stent. Alternatively, it may form a hematoma (collection of blood outside the kidney or ureter). While it can often be observed (it eventually disappears), occasionally a drainage of the hematoma is necessary. If bleeding persists, treatment ranges from observation in the hospital to an angiogram (minimally invasive procedure in which a bleeding vessel can be stopped). A need for open surgery and even possibly nephrectomy (removal of the kidney) is extremely rare, as is a requirement for transfusion.
- Ureteral Injury: In this procedure, we intentionally make a full-thickness (through the entire wall) incision in the ureter. Despite precautionary measures, any portion of the ureter may be significantly injured from the scope or from the instruments used to perform the procedure. The solution is typically to end the procedure, placing a stent(plastic tube) in the ureter to allow the tissue to heal itself over a few weeks. For patients undergoing a retrograde procedure, an injury may necessitate placement of a nephrostomy tube (see above) such as in the antegrade approach. A complete separation of the ureter from the bladder or kidney (ureteral avulsion) is an uncommon occurrence and requires open surgery through an incision to repair.
- Injury Due to Percutaneous Access: This type of complication is rare and may present itself immediately during the operation or shortly thereafter. In the antegrade approach, access is gained to the renal pelvis through the back.
During access placement, any of the following are possible:
- pneumothorax (partial or complete lung collapse) requiring temporary placement of a special chest tube for a few days
- spleen (left side procedure) or liver (right side procedure) injury--treatment could range from observation to
- angiogram (if significant bleeding), or even open surgery (a general surgeon may be asked to assist with this problem)
- colon (large intestine) or bowel (small intestine) injury--treatment is usually open surgery (by a general surgeon) if the hole is significant (a general surgeon may be asked to assist with this problem)
- Urinary Retention: In males the prostate can become swollen from the scope pressing against it or less commonly secondary to infection. In this instance, a catheter would be placed and your doctor would discuss the next step.
- Patients at greater risk are those who already have difficulty urinating before the procedure due to BPH (benign prostatic hypertrophy).
- Deep Vein Thrombosis (DVT)/Pulmonary Embolus (PE): In any operation(especially longer operations or those in which your legs are in stirrups), you can develop a clot in a vein of your leg (DVT). Typically, this presents 2-7 days (or longer) after the procedure as pain, swelling, and tenderness to touch in the lower leg(calf). Your ankle and foot can become swollen. If you notice these signs, you should go directly to an emergency room and also call our office. Although less likely, this blood clot can move through the veins and block off part of the lung (PE). This would present as shortness of breath and possibly chest pain. We may sometimes ask the medical doctors to be involved with the management of either of these problems.
We provide this literature for patients and family members. It is intended to be an educational supplement that highlights some of the important points of what we have previously discussed in the office. Alternative treatments, the purpose of the procedure/surgery, and the points in this handout have been covered in our face-to-face consultation(s).
The information contained in this document is intended solely to inform and educate and should not be used as a substitute for medical evaluation, advice, diagnosis or treatment by a physician or other healthcare professional. While Delta Medix endeavors to ensure the reliability of information, such information is subject to change as new health information becomes available. Delta Medix cannot and does not guaranty the accuracy or completeness of the information contained in this document, and assumes no liability for its content or for any errors or omissions. Please call your doctor if you have any questions.
Delta Medix, P.C.