Flexible ureterorenoscopy (RIRS) for complex calculi
Retrograde Intrarenal Surgery techniques are absolutely remarkable. It is performed by a qualified urologist by passing the endoscope through the urethra into the bladder and through the urethra into the collecting drainage system of kidney.This avoids resorting to major operations of cutting open the body or even puncturing the kidney. This is a day-care surgical procedure done inside the kidney with a thin (2-3mm) flexible viewing tubebetter known as a flexible ureterorenoscope (FURS). Due to recent technological strides in this field, it has become possible to implement Retrograde Intrarenal Surgery (RIRS) to manage kidney stones and small tumors. Typically a laser energy is used to dust the stones (or burn the tumor as the case may be). Very fine (less than 1 mm in dia) forceps are available to pick up stone fragments or tumors.
How is the surgery performed?
Before procedure :Preoperative checkups are done to ascertain the position of the stone, function of the kidney, reasons for forming stones, presence of infection, general health condition of the patient and fitness for anesthesia. Typically a battery of laboratory tests (blood and urine) and radiology tests (either x-ray with ultrasound or a CT scan of kidney-ureter-bladder region, x ray of chest, and if indicated ECG, chest x ray, echocardiography) are performed before consulting anesthesiologist. Once all the tests and consultations confirm fitness for the procedures, patient is typically admitted on the day of surgery (or the evening prior) and is made to fast for 4-6 hours before the surgery.
The Surgery: In the operation theater, firstly the patient is put under anesthesia [either fully asleep (general anesthesia) or lower body numb (spinal anesthesia)]. The patient is positioned in lithotomy position, a position in which women give birth. An antibiotic is given through intravenous injection. After surgically cleaning the private parts, the flexible URS is passed under camera vision from urine passage via bladder and ureter into the kidney. The stone (or tumor) is visualized and then precisely dusted with holmium laser which is delivered through a very thin wire, called fiber (0.2 – 0.3mm in dia). At the end of the procedure a thin long polymer tube, called double J stent, is left inside the urinary system (from kidney to bladder); it is typically removed in 2-4 weeks time by a small endoscopic procedure cystoscopy. Unlike stents for heart attack, this is a temporary tube to assist in healing and comfort to patient and must be removed in stipulated time decided by the doctor.
The ureteroscope can easily remove kidney stones of upto 20mm size; in expert hands, even larger stone can be treated thus avoiding bigger surgical procedures (like PCNL which entails puncturing the kidney). However, for treating larger stones, the procedure may have to be repeated several days apart.
Post-surgery: After completing RIRS, the patient will be taken to the recovery room where he will be monitored for vitals, pain and side effects, if any. A urinary catheter may be placed into the urethra for few hours for continuous drainage of urine. The patient may be discharged the same day (after at least 6-8 hours of observation) or the next day as per patient comfort and clinically suitable. Typically patient is advised to take few medications for pain and discomfort, and plenty of liquids (3-4 liters a day). Generally antibiotics are not prescribed beyond 24 hours. He / she is advised to return in 5-7 days after surgery to check for general health and presence of infection.