I. Classical percutaneous nephrolithotomy surgical methods
1.Percutaneous renal approach
(1) Patient position: prone position after retrograde cannulation. The affected side is padded 25 degrees.
(2) Selection of the puncture point: the most commonly used position is: on the posterior line of the internal organs under the 12th rib.
(3) Injection of contrast agent or air via retrograde catheter
(4) The C-arm X-ray is first positioned at 90 degrees and then moved 25-30 degrees so that the top of the penetrating needle overlaps the ray.
(5) The penetrating needle is entered into the renal collection system, the needle core is removed and urine is seen to flow out, then a metal guidewire is placed in the kidney and expanded first to F9 with a fascial dilator, then an F9 cobra-like catheter is placed, and the guidewire is introduced as far as possible into the ureter under X-ray fluoroscopy.
(6) The F8 catheter is placed via the guidewire, and this tube is dilated with AMPLAZ dilator tube F10 with sheath, leaving the sheath before placing another guidewire (safety guidewire), and this guidewire is fixed to the skin with a needle and thread.
2. Percutaneous nephrostomy tract dilation
On the F8 catheter, a series of dilatation to F24-F30 with sheath is performed with AMPLAZ dilatation tube.(under X-ray surveillance), leaving the sheath.
3. via the AMPLAZ sheath, a nephrostomy or ureteroscope is placed.
II. Percutaneous nephrostomy ureteroscopy procedure
1.Percutaneous renal approach
(1) Patient position: prone position. The affected side is padded 25 degrees.
(2) Selection of the puncture point: the most common position is: 12 ribs under the internal organs on the posterior line.
(3) The C-arm X-ray, 90 degrees positioning, with a metal object to determine the location of the stone calyces, penetrating needle in the 12-rib lower internal organs on the posterior line laterally into (about 30 degrees) the renal collection system, the needle core will be removed, see the urine outflow, and then injected with a syringe thin contrast, put the metal guidewire in the kidney, preferably so that the guidewire can enter the ureter, if difficult, try to place in the calyces.
2.Dilation of percutaneous nephrostomy tract: series of dilatation with fascial dilator along the metal guidewire to F14-16. and leave the outer sheath.
3.Transcatheter F14-16 sheath and place ureteroscope for observation or treatment.
3. Application of percutaneous nephrolithotomy
Percutaneous nephrolithotomy is an important part of endoluminal urological surgery, and has become the main modern treatment method in the treatment of upper urinary tract stones, together with ureteroscopy and extracorporeal shock wave lithotripsy, which has completely changed the traditional open surgery surgical treatment.
The history of percutaneous nephrolithotomy can be traced back to the 1940s, when Papel and Brow were the first to remove residual stones from the surgical nephrostomy using an endoluminal mirror, and Goodwin suggested the method of percutaneous renal puncture stoma in 1955, which started a new era of percutaneous nephrolithotomy. After 1982, the procedure was carried out in Beijing, Guangzhou, Nanjing and other places in China, and after more than 10 years of clinical practice, thousands of surgical experiences were accumulated. Through the comprehensive treatment methods of percutaneous nephrolithotomy, ureteroscopy and extracorporeal shock wave lithotripsy, more than 90% of kidney stones and more than 95% of ureteral stones can be removed from surgery. Moreover, we have improved the method of percutaneous nephrostomy in clinical practice, innovated percutaneous nephrostomy microstomy and percutaneous nephrostomy ureteroscopy for stone extraction, introduced pneumatic ballistic lithotripter and laser lithotripter, ureteral endoscopy and various dilating catheters, etc., so that the success rate of treatment has been increasing, the comorbidity has been reduced and the treatment scope has been expanded. For example, some complicated cases such as residual stones after open surgery, ESWL, pelvic ureteral junction stenosis or atresia and hydronephrosis, and urinary leakage after upper urinary tract surgery can be treated by endoluminal techniques, which has led to the rapid development of the specialty of endoluminal urology.
Percutaneous nephrostomy is one of the basic techniques of endoluminal urology and is the basis for the realization of percutaneous nephrolithotomy. A safe and definitive fistula not only prepares for further examination and treatment, but also is a good treatment tool in itself, which can effectively solve the drainage of hydronephrosis, renal infection and even septic kidney caused by various obstructive factors and help restore the function of the obstructed hydronephrosis kidney. With the accumulation of experience and proficiency in operation, percutaneous nephrostomy has gradually replaced open fistula.
Since percutaneous nephrostomy and percutaneous nephrolithotomy are invasive, the previous operation is tedious, and the dilated channels are large and prone to injury and bleeding, which affects the popularization of this technology. We have accumulated more than 10 years of experience in more than 1000 cases of percutaneous nephrolithotomy and proposed percutaneous nephrostomy and percutaneous nephrostomy ureteroscopy (minimally invasive percutaneous nephrolithotomy). They are characterized by small trauma, accurate positioning, simple operation, low intraoperative bleeding, rapid patient recovery, and easy promotion.
(A) Percutaneous nephrostomy microfistula
1.Nephrostomy instruments
(1) puncture needle: U.S. TLA/renal puncture needle, trigonal pointed core, 18 gauge metal sheath, can insert 0.035-0.038 inch guide wire. Or German kidney puncture needle (three sets of needles), for an 18-gauge metal sheath with a small needle core with a thinner core, which reduces the degree of puncture injury.
(2) Metal guidewire: 0.035 inch or 0.038 inch diameter, over 120 cm long J-tip soft tip metal guidewire.
(3) dilators: metal, polymer materials, rod-like, tubular and balloon catheters and other kinds. Nowadays, plastic tubular dilators are mostly used, and fascial dilators are more practical, made of polyurethane impervious to X-rays, from F6 to F18, in F2 increments, with a thin Peel-away plastic sheath from F12 onwards.
(4) Fistula tube advocate the use of soft and rigid, thin-walled transparent PVC catheter, commonly used F10-14, for the localization of disposable products have been sterilized. There is a full set of foreign products with puncture needle, dilatation tube and fistula drainage bag, for single-use, more expensive.
2.Surgical indications
(1) Various obstructive or unexplained hydronephrosis.
(2) Post-operative upper urinary tract obstruction, stenosis, atresia, infection or septic kidney.
(3) ESWL postoperative stone street or residual stones in the kidney.
(4) Multiple kidney stones, cast or antler-shaped stones, especially recurrent stones after open surgery.
3. Contraindications to surgery.
Except for systemic bleeding disorders, there are no obvious absolute contraindications. Hypertension, diabetes mellitus, systemic infection should be corrected first, and bleeding tendency should be noted in severe chronic renal insufficiency.
2.Anesthesia and body position
(1) Usually performed under local anesthesia, skin and renal peritoneum for infiltration anesthesia, B ultrasound or X-ray positioning, such as hydronephrosis is obvious, can be performed without positioning.
(2) lying down, a small pillow under the abdomen in the kidney area makes the waist and back into a plane, and the screen abandons the vertical puncture method with a 30° pad on the affected side to make the patient feel more comfortable, and the X-ray can be used for vertical fluoroscopy to facilitate selective localization of the puncture. The doctor can leave the X-ray machine slightly for operation to reduce the dose of radiation received.
3.Surgical steps
(1) From the skin of the posterior axillary line under the 12th rib for the entry point, according to the actual situation can be made appropriate changes, usually the direction of puncture is to the patient’s internal anterior superior oblique needle, with the level of 30 ° – 60 °. The longitudinal axis of the body is 50°-80°.
(2) The tail of the needle can be seen swinging with breathing when penetrating the peritoneum of the kidney, and there is an obvious feeling of breakthrough when a large hydronephrosis kidney is penetrated into the collection system, and this feeling is not obvious in the kidney without hydronephrosis or after open surgery. When the needle core is removed after penetration into the renal collecting system, a urine drip can be identified and injected with pantopamine diluted to 36%, and the puncture site and renal collecting system can be clarified under X-ray fluoroscopy.
(3) Introduce a 0.035 or 0.038 inch metal guidewire through the metal sheath of the fistula needle, preferably into the ureteral lumen, which should be more than 5 cm if coiled in the kidney, and after withdrawing the needle sheath, prick the skin and fascia along the guidewire with a small sharp knife, and cut deeper into the scar if there is a postoperative scar.
(4) The fascial dilator is placed over the guidewire and the channel is dilated toward the kidney, operated by the same surgeon, with one hand straightening the guidewire slightly backward and the other hand rotating the dilator and advancing it forward. From F6 to F14, the depth of each push is kept equal to avoid bending the metal guidewire or pushing too deep to penetrate the renal pelvis, and the process is observed by intermittent X-ray fluoroscopy. Finally, the F12 or F14 dilatation tube is pushed into the renal pelvis together with the corresponding Peel-away thin sheath.
(5) Withdraw the dilatation tube and insert the corresponding size PVC tube along the guidewire from the thin sheath into the renal collecting system and understand the position of the tube under X-ray fluoroscopy.
(6) Take No. 4 wire and tie it through the skin on each side of the fistula tube, and make a winding knot to fix the fistula tube, and connect the lead end to the urine collection bag.
(2) Percutaneous nephrostomy ureteroscopic lithotomy
With the wide development of extracorporeal shock wave lithotripsy, percutaneous nephrolithoscopy alone as a stone retrieval has been reduced, but some huge stones, complex stones treatment, domestic and foreign scholars advocate combined treatment to improve the efficacy and shorten the course of treatment. Conventional percutaneous nephrolithotomy requires expansion of the channel up to F24-36, which increases the risk of bleeding due to the large channel, and it is difficult to operate the normal nephrolithoscope in the hydronephrosis-free kidney and the upper ureter, which affects the development of this technology. After more than 10 years of clinical practice, the use of percutaneous nephrostomy and extraction of stones by F8-11.5 ureteral rigidoscope has greatly improved the success rate and reduced complications and patient’s pain in some patients with complex upper urinary tract stones, residual stones after surgery or pelvic outflow tract stenosis or atresia after surgery, with satisfactory results.
1.Surgical steps
(1) Phase I lithotripsy, epidural anesthesia, dilatation of F16-18 according to the steps of percutaneous nephrostomy (1-4), leaving the corresponding Peel-away sheath, and ureteroscopic lithotripsy or lithotripsy can be obtained from the channel.
(2) Phase II lithotripsy is performed 5-7 days after nephrostomy and 3-5 days after phase I lithotripsy. The patient is positioned as in microstomy, with routine epidural anesthesia and sterilization, a metal guidewire is introduced through the fistula, the position of the guidewire is observed under X-ray fluoroscopy, and the channel is slightly dilated, usually to F16-20 and the corresponding Peel-away plastic thin sheath is left behind. The ureteroscope is inserted through the channel into the kidney for observation and manipulation. Small stones can be removed directly, while larger stones need to be broken up with a lithotripter. At present, pneumatic ballistic lithotripsy has gradually replaced ultrasonic lithotripsy, and the former is tens of times more efficient than the latter, which can shorten the operation time. Attention is paid to first treating the stones in the calyces where the fistula is located and removing the stones from the renal pelvis and outlet, and removing the stones while lithotripsy is performed, with irrigation fluid flushing to maintain a clear view of the lumen.
(3) Then turn and swing the angle of the ureteroscope to observe the renal calyces in all directions, and even reach the upper ureter through the renal pelvis. The new generation ureteroscope is a fiberscope with a thin and flexible body, which is slightly bent without changing the shape of the field of view and can enter the narrow calyx neck and upper ureter to treat stones.
The only disadvantage is the small field of view and the habitual process of observation. For stones in the calyces that are too large for the angle of swing of the ureteral rigidoscope, the tendency is not to force complete extraction, but to combine ESWL treatment, or, if ESWL treatment is difficult, to use curvilinear fiberscope treatment, when the laser lithotripter plays an advantage, although the operation will feel inconvenient.
When the procedure is over, depending on the case, a guidewire is inserted into the ureter up to the bladder, an F5-6 double J-shaped catheter is placed, and the corresponding nephrostomy tube is left in place. If the stone is removed or treatment is complete on postoperative radiograph review, the fistula can be removed 2-3 days later. If the stone is not removed for special reasons, the fistula will be retained until the stone is removed again.
(iii) Multi-channel percutaneous nephropuncture for complex kidney stones
PCNL has been widely reported to be a reliable method for the management of kidney stones. However, some complex kidney stones, such as antler-shaped stones, multiple stones, postoperative residual stones, and combined UPJ stenosis, have a unique position for PCNL alone. Single-channel operation is slow and stone removal from several calyces is limited, which can be compensated by multichannel puncture.
In general, the first puncture channel is used to enter the middle or lower calyces to treat the renal pelvis and puncture calyces first, while the second and third channels are used to puncture the calyces where the first channel cannot reach, mostly under X-ray positioning, which is more accurate. The Peel-away sheath is left in place after the guidewire is dilated, so that the ureteroscope can enter the calyces in a larger area to retrieve stones.
In addition, the two-way flushing can avoid the dead angle formed by one-way flushing, and the perfusion solution can be flushed into the lithotripsy channel or non-lithotripsy channel according to the actual situation, which can greatly accelerate the speed of stone extraction. It also avoids the spread of infection caused by one-way flushing.
With this method, the clearance rate of complex stones reaches more than 84%, and renal pelvic outflow tract obstruction and UPJ stenosis can also be treated simultaneously or separately by endotomy or dilatation, and the double J tube is routinely left in the postoperative line.