A stent is a mechanism that is placed inside the vena cava and ducts to widen narrowing areas. Let's take a closer look at how a kidney stent works and what it looks like. And at the same time we will tell you why it is introduced. As a rule, a stent is most often prescribed for kidney stones or when the flow of urine is impaired due to adhesions.
The operation is easy and fast. In most cases, the mechanism is installed for a period of 2-3 months until the normal physiological outflow of urine is restored.
What is a stent?
Renal stent - a tube up to 30 cm long and 1.5-6 mm in diameter. The implant allows urine to pass from the kidney to the bladder in cases where the normal outflow is impaired. This happens for a variety of reasons. One end is attached to the kidney itself, the other - in the bladder.
The implant was created from special materials that do not cause allergies. If the allergic reaction nevertheless began, the stent is urgently taken out and placedimplant from another material.
Why do I need a kidney stent? How it works
A stent is needed to expand narrowed ducts, due to adhesions, for example, or in a complicated pregnancy. Urine is produced in the kidneys and gradually accumulates in the bladder, passing through thin tubules - the ureters.
If the ureter does not pass fluid for some reason, such implants are invented to artificially expand the narrowed sections of the ureter.
Installation of a stent in the kidney is sometimes a vital operation. Failure of the kidneys leads to the failure of the liver, and without these organs, a person dies. If one kidney can be saved, the person will be dependent on hemodialysis for life.
Types of renal tubes
The stent should not be exposed to the destructive action of s alts and at the same time be contrast. It is necessary to control its condition and location. If the tube is dislodged or ruptured, urgent surgery is needed.
Stents come in a variety of lengths and materials; implants also differ in the end of the tubes. Some have curved "tails" on both sides for better fixation, others only on one side of the implant.
The material of the tube and its shape are selected individually. The doctor takes into account the age of the patient, his general condition and tendency to allergies. What materials are used? Typically, tubes are made of silicone, metal or polyurethane. For a silicone tube, the residence time in the body is up to 8 weeks. More expensive alloys alloweddelete after 3-6 months.
Indications and contraindications for installation
Installation of a stent in the kidney is carried out strictly according to medical indications.
Indications in medicine are:
- stenosis (stricture) of the ureter;
- urethrohydronephrosis;
- kidney cancer;
- swelling of the ducts due to a prolonged inflammatory process in the bladder;
- narrowing of the ureter due to the growth of the uterus in a woman during pregnancy;
- in men, stenosis occurs due to prostatitis;
- kidney stone stuck in the canal.
A stent can be placed after removal of a kidney stone if sand or smaller stones are still found in the kidneys.
Contraindications are 2 factors: if there is an injury to the urethra or an acute inflammatory process in the pelvis is diagnosed.
Setting methods
Current blockage of the urinary tract is not a particularly difficult medical problem. Installation takes half an hour, and complications do not occur in most patients. How is a kidney stent placed?
So there are 2 installation methods. The first is retrograde, the second is antegrade.
- Retrograde. The implant is inserted through the urethra and bladder. The operation takes 25-30 minutes on the strength. A balloon with a mesh is inserted, it expands in the right place, the mesh as a frame holds the walls of the duct, and the balloon itself is removed from the body.
- Antegrade. An incision is made in the peritoneum. The structure is inserted into the kidney through a nephrostomy device, and a catheter attached to the urinal is placed to remove urine.
After 1-2 months, a new study is conducted. And the doctor, based on the results of the subsequent cystoscopy, decides whether to remove the stent or install a new one.
Diagnosis of stenosis
How is renal duct narrowing diagnosed? The patient himself can notice this by signs of stenosis, which, by the way, cannot be ignored.
Ductal stenosis symptoms:
- raising the temperature;
- sharp pain in the lumbar region;
- little urine, it is cloudy;
- sometimes nausea and vomiting occur.
With these symptoms, a stent is a must. Kidney surgery is an unpleasant, but extremely necessary procedure. Otherwise, hydronephrosis develops.
Hydronephrosis worsens symptoms. The temperature is very high, pain during urination, sometimes the patient cannot go to the toilet at all. Call an ambulance immediately after the onset of pain (hepatic colic), nausea and headache.
As soon as the doctor checks the history (collected information) and receives the results of the ultrasound of the kidneys, he will be able to give an opinion and prescribe an operation to install a stent.
Before the operation, several more mandatory diagnostic procedures are performed:
- Renal MRI;
- ultrasound;
- excretory urography.
During these procedures, it is necessary to establish the degree of narrowing of the ducts, the underlying cause and some physiological characteristics of the patient. The stent is selected taking into account allfeatures of the structure of the ducts, and in different people these physiological features can vary greatly.
How is the operation going?
The stent is inserted through the urethra and passed into the renal pelvis. The tube is attached directly to the tissues of the kidney thanks to a special spiral end twisted in the form of a pig's tail.
Through a cystoscope, the doctor finds an abnormally narrowed place in the ureter and a mesh called a balloon is placed there. The mesh expands and the duct is thus reopened.
Depending on the complexity of the situation and the expiration date of the tube itself, the period for removing the implant from the body is set. The operation can be canceled if acute inflammation has begun again immediately before the installation. Then suitable antibiotics are prescribed, and the operation is postponed.
Implant during pregnancy
Gestational pyelonephritis can develop in pregnant women due to infection in the urinary tract and double stress on the kidneys. Against the background of pyelonephritis, strictures develop and, accordingly, complications arise, due to which the pregnant woman has to install a stent in the kidney.
Doctors do not recommend surgery to remove stones for pregnant women. So they put in a stent or nephrostomy, and after giving birth, after about 2 months, the stent is removed.
Complications after installation
In rare cases, there are complications after stenting. And the patient has to do an emergency operation - to replace the tube in the kidneys with a new one. This happens for the following reasons:
- Stent stuck in ureter.
- Rejection started.
- During the operation, an infection got inside the kidney and an inflammatory process began.
- Migration of the stent in the kidney, i.e. displacement due to the fact that the tube was not firmly fixed.
- Tube burst.
- Formation of many urine crystals on the silicone tube. Also need to be deleted.
And also highlight special, rarer complications. These situations require immediate medical intervention.
- Occurrence of an allergic reaction to the stent.
- Swelling of the inner wall of the bladder.
- The appearance of blood clots in the urine.
- If the implant is too hard, sometimes hematomas appear inside the organs.
To make sure that none of the listed complications are present, the patient is observed in the hospital after installation within 48 hours, then discharged home.
Stenting after surgery
Sometimes an implant is placed during or after surgery. The tube may be placed after reconstructive surgery of the pelvic organs, during the surgical removal of large stones, or after a kidney transplant. Postoperative swelling interferes with the flow of urine, and stagnant urine can cause additional inflammation.
The stent in the kidney after surgery is usually removed after a couple of months, during a routine cystoscopy. If severe hydronephrosis is diagnosed, the patient may be dependent on stents for life. Thena suitable alloy is selected and, at regular intervals, is removed and replaced with the same, but with a new one.
General recommendations in the postoperative period. Food restrictions
For a speedy recovery, the patient is advised to strictly follow the diet and drinking regimen. It is forbidden to drink alcohol even in small doses while the stent is in the kidney.
It is important that vitamins and minerals get into the body, vitamin C is especially important. Fatty foods should be avoided. At the time set by the doctor, be sure to come for an ultrasound scan to examine the condition of the ureteral stent in the kidney and the kidney itself. The doctor should examine the organ and make sure there is no inflammation.
Delete
The first and most important rule is that the procedure for removing the stent from the kidney must be carried out on time. If you miss the date, the material will begin to overgrow with s alt crystals, it is more difficult and painful to remove it in this form. The procedure is performed under local anesthesia. Children are removed however under general anesthesia.
Same as when inserting a balloon, a cystoscope is inserted through the urethra, the stent is examined. Then the grid is poured with cold water, it narrows and in this form it is simply brought out.
Solving the problem of crystal formation
In 90 percent of people walking with kidney stents, s alt crystals completely destroy the framework, so often the stent has to be removed even faster than planned. To slow down the process of s alt erosion, it is recommended to drink special herbs, herbal remedies.
Tube replacement operation is not alloweddrag out. As soon as the replacement period has come, you should immediately go to the hospital.
Prevention of stenosis and hydronephrosis
It is not yet possible to prevent the appearance of such problems with the kidneys. Some people are more prone to kidney stones, others don't even know what it is. Of great importance is the way of life, his habits and heredity.
In any case, in order to maintain the he alth of the kidneys, it is recommended to regularly do preventive examinations, ultrasound of the pelvic organs - it will not hurt. Drinks such as coffee, alcohol, energy drinks, if drunk immoderately, can lead to various diseases of the urinary system, so it is better to limit or completely eliminate their use.
Pregnant women begin with kidney problems due to reduced immunity. Before planning a pregnancy, it is advisable for women to examine their kidneys. If they are weak, there may be complications during pregnancy.
Prevention of adhesive processes is timely diagnosis and measures taken for treatment. To avoid stenosis, men need to be regularly checked by a urologist, because prostatitis also leads to inflammation of the urinary tract, and therefore to adhesive processes.
