Quality control standards for renal puncture biopsy
1.Practitioner qualification
The physician who performs percutaneous renal puncture biopsy should obtain the “Physician’s Practice Certificate”, and the scope of practice should be a physician specializing in internal medicine or Chinese medicine, with more than 3 years of clinical work experience in renal specialty.
2.Hardware conditions
(1) There should be a percutaneous renal puncture biopsy room, equipped with indoor ultraviolet disinfection equipment. Zhao Hongwen, Department of Nephrology, Chongqing Southwest Hospital
(2) Configuration of Doppler ultrasound diagnostic instrument, (semi-)automatic biopsy gun or negative pressure suction device, biopsy needle, etc.
(3) Color ultrasound (for real-time monitoring)
(4) ventilator (intravenous compound anesthesia patient backup)
3, the indications and contraindications of renal puncture biopsy
3.1 Indications
Any diffuse renal parenchymal damage, including primary or secondary glomerular disease, tubulointerstitial disease, etc. are indications for renal biopsy.
(1) nephrotic syndrome.
(2) Nephrotic syndrome.
(3) Acute nephritis syndrome.
(4) Persistent asymptomatic urinalysis abnormalities [proteinuria and/or microscopic hematuria of glomerular origin].
(5) Acute hyperalgesia of unknown cause.
(6) Chronic hyperalgesia of unknown cause. and incomplete reduction in kidney volume.
(7) Renal biopsy of transplanted kidney: all types of non-surgical factors leading to renal hypofunction of transplanted kidney, delayed recovery of renal function, tubular necrosis, drug nephrotoxicity, chronic rejection and suspected recurrent or new glomerular disease.
(8) Repeat kidney biopsy may be performed according to the need of the condition.
3.2 Contraindications
3.2.1 Absolute contraindications
(1) Obvious bleeding tendency.
(2) Those who do not cooperate with the operation.
(3) Consolidated kidney, small kidney and isolated kidney.
(4) Renal hemangioma, spongy kidney or polycystic kidney.
3.2.2 Relative contraindications
(1) Active pyelonephritis.
(2) Renal ectopic or wandering.
(3) Uncontrolled severe hypertension.
(4) Excessive obesity.
(5) High degree of ascites.
(6) Other: severe cough, abdominal pain and diarrhea, severe anemia, cardiac insufficiency, pregnancy or advanced age.
4.Pre-operative preparation for renal puncture biopsy
4.1 Routine preoperative preparation for renal puncture biopsy
After the indications for renal biopsy are clearly defined, the necessity and safety of renal biopsy should be explained to the patient and family members, and the operation procedure should be briefly explained to eliminate their concerns and obtain the best cooperation and written signed consent.
(1) Ask for a detailed medical history, paying special attention to the history of bleeding.
(2) Understand the patient’s general condition, cardiopulmonary function, renal function, and ultrasound to determine the size, location and mobility of both kidneys.
(3) Control hypertension effectively.
(4) Check blood routine and blood clotting index. Check blood type and blood preparation as needed for the condition.
(5) Those who have been treated with anticoagulation before surgery should discontinue anticoagulant drugs and consider the time of discontinuation according to the half-life of anticoagulant drugs and recheck coagulation indexes.
(6) Patients with liver disease at high risk of bleeding may receive oral or intramuscular VitK1 2-3 days prior to surgery.
(7) Train patients to hold their breath at the end of inspiration in prone position and to urinate in bed.
(8) Ask the examined patient to defecate within 12-24h before surgery.
(9) Female patients undergoing non-emergency renal biopsy should try to avoid menstrual period.
(10) Those with severe renal failure should have enhanced dialysis prior to surgery.
(11) Preoperative sedation may be applied as appropriate for those who are overly stressed.
4.2 Preoperative anesthesia preparation for renal puncture biopsy
Choose the anesthesia method according to the patient’s condition: local anesthesia at the puncture site or intravenous compound anesthesia. No special preparation is needed for skin local anesthesia. If intravenous complex anesthesia is chosen, anesthesia preparation is required.
(1) Anesthesia assessment by anesthesiologist, informed consent for anesthesia and signature.
(2) Prepare the intravenous anesthesia drugs by giving an indwelling needle in advance.
(3) Prepare a ventilator for backup.
(4) Fasting from food and water for 6 h before surgery.
5. Renal puncture biopsy operation procedure
5.1 Body position
The patient is placed in a prone position with the abdomen under the rib cage (equivalent to the position of the kidney area) padded to reduce kidney movement. Both upper limbs are placed at the sides and the head is tilted to one side. The patient is instructed to breathe calmly.
5.2 Puncture site selection
The right kidney or the lower pole of the left kidney, guided by ultrasound positioning.
5.3 Skin disinfection
Routinely disinfect the skin and spread the towel, including the upper to the subscapular line, the lower to the line of the posterior superior iliac spine, and the sides to the posterior axillary line, and then spread the towel.
5.4 Anesthesia
(1) local anesthesia of the skin at the puncture site: subcutaneous local anesthesia along the route of needle entry up to the perirenal fascia, usually the syringe will cause negative pressure at the same time as the first needle, if there is no bleeding while withdrawing the injection needle and injecting local anesthetic solution.
(2) intravenous compound anesthesia: peripheral intravenous push fentanyl (body mass less than 60 kg 50μg, more than 60 kg 75μg), and then slowly intravenous push Deprenyl (isoproterenol), according to the patient’s response to stimulation to adjust the dosage, the eyelash reflex disappears that the injection of drugs. If the patient’s arms and legs move when the puncture needle enters the skin, the anesthesiologist should add 10-30 mg of isoproterenol as appropriate. monitor blood pressure, heart rate and oxygen saturation during intravenous anesthesia.
5.5 Puncture method
Tru-Cut biopsy needle automatic biopsy gun puncture method: After loading the 14G or 16G puncture needle into the gun slot, close the lid of the puncture gun, open the safety button, and under the real-time guidance of the ultrasound probe, send the puncture needle percutaneously to the peritoneal surface of the kidney, if the patient is under local anesthesia, ask the patient to hold his breath, the operator presses the fast needle button of the puncture gun, and quickly removes the puncture needle to take out the kidney tissue in the cutting slot. If the patient is under intravenous compound anesthesia, observe the patient’s respiratory rate, and during the patient’s respiratory interval, the operator presses the rapid needle-in button of the puncture gun and quickly removes the puncture needle to remove the kidney tissue in the cutting slot.
5.6 Specimen length
The length of the kidney tissue taken is usually 15-20 mm, and a competent take should include both the renal cortex and the renal medulla. Repeat puncture may be performed when the kidney tissue taken is insufficient or empty.
5.7 Delivery
The kidney tissue is divided and processed by the pathology technician according to the requirements of each pathological examination and sent for examination immediately. Usually, light microscopy, immunopathology and electron microscopy are performed. Light microscopy and electron microscopy are fixed with the appropriate fixative, and the kidney tissue is placed on a low-temperature saline soaked dressing for immunofluorescence examination.
5.8 Wound dressing
Dressing covers the wound after renal puncture and is fixed with gauze or adhesive tape. Transfer to a lying position.
5.9 Patients with intravenous compound anesthesia are awakened by the anesthesiologist’s company and sent back to the ward after stable vital signs.
6. Post-renal puncture care
(1) Apply pressure at the renal biopsy puncture site for 3~5min after renal puncture.
(2)After the operation, the patient should be placed in a flat position with strict lumbar braking for 6h (the limbs can be relaxed and moved slowly in small increments, while turning and twisting the waist are strictly prohibited). If there is no hypertension, renal insufficiency and other high-risk patients, the patient should be bedridden for 24h after renal biopsy.
(3) Blood pressure, pulse (1/0.5h×4+1/h×4), urine routine, observation of skin, facial color, sweating, lumbar and abdominal symptoms and signs should be routinely detected after surgery.
(4) Blood pressure drop or carnal hematuria should be repeatedly checked with routine blood count and hematocrit, and ultrasound should be performed for significant lumbar and abdominal pain to observe the presence of subperitoneal hematoma.
(5) Avoid or promptly deal with constipation, diarrhea and violent cough.
(6) Prohibit strenuous exercise or heavy physical labor within 3 weeks after surgery.
7. Post-renal puncture complications and management
7.1 Hematuria
The vast majority of patients have microscopic hematuria after surgery, while the incidence of carnaroscopic hematuria is low. Most of the carnal hematuria occurs in the first urine after surgery, and the color of urine gradually turns clear after 3~5 urinations, usually not more than 2 days. In a small proportion, delayed carnitic hematuria also occurs 3~12 d after surgery.
7.2 Perirenal hematoma
Perirenal hematomas are also more common after renal biopsy and are mostly small hematomas. It is often clinically manifested as hypothermia and lumbar pain 3-5 d after renal biopsy and confirmed by ultrasound examination.
Small perirenal hematomas can be absorbed and dissipated on their own without sequelae by bed rest, and larger hematomas can be absorbed within 3 months.
7.3 Hemorrhage
Aggressive hemostatic measures should be taken for the extreme minority of patients with severe sarcoid hematuria, including continuous intravenous pumping of posterior pituitary hormone, intramuscular or subcutaneous injection of hemagglutinin (lithotriptan) and intravenous infusion of vitamin K1, but the use of coagulants that tend to form blood clots is not advocated. When the patient’s hematocrit drops more than 6% or hemoglobin drops more than 20g/L or hemodynamic instability, intravenous fluid must be supplemented to maintain normal circulation of blood substances and more urine discharge to keep the urinary tract open and prevent clots from blocking the urinary tract. If hematocrit and hemoglobin continue to decline, blood transfusion, selective renal arteriography interventional embolization and, if necessary, surgery should be performed to control active hemorrhage. Management of severe perirenal macrohematoma is similar to that of a patient with severe carnal hematuria.
7.4 Urinary retention
Postoperatively, some patients develop urinary retention due to emotional stress such that they require assistance with urination as well as catheterization for urination. Those who develop significant carnal hematuria with a high number of blood clots in the urine are prone to urinary tract obstruction leading to severe urinary retention. In the latter case, percutaneous cystocentesis catheterization or triple-lumen catheterization should be used to repeatedly flush the bladder until the patient’s bleeding ceases.
7.5 Arteriovenous impotence
Unexplained hypertension after renal biopsy and a vascular murmur usually audible at the biopsy site of the transplanted kidney recipient should be considered arteriovenous impotence, and Doppler ultrasonography or renal arteriography can confirm the diagnosis. Most patients can self-resorb within 1 to 2 years, and severe cases can be treated with embolization during selective arteriography.
7.6 Perirenal pain
Mostly mild dull pain, longer and more severe pain may be due to hematoma enlargement and/or urinary tract obstruction. For patients with severe postoperative pain, or patients with bilateral lower limb medial pain (or abdominal pain) without perirenal pain, and those with serious sweating at the same time, blood pressure and heart rate changes should be closely observed and hematocrit and hemoglobin concentration should be measured in time, and serious bleeding should be treated promptly when determined.
8. Emergency plan for bleeding after renal biopsy
8.1 Sarcopenic hematuria.
Sarcopenic hematuria occurs mainly because the puncture point is too high, the puncture is too deep, and the tissue taken is too long (more than 1.6 cm), which injures the renal calyces or larger blood vessels. Carnal hematuria mostly occurs on the day of biopsy when the first urination occurs; however, it can also be delayed until 1-2 weeks after the procedure and is mostly associated with excessive activity. Carnal hematuria is mostly single or disappears within 1 d. Nearly 90% of cases disappear within 3 d. Only slightly some cases (less than 5%) of carnal hematuria can last for 1 week or longer. In individual cases, hematuria is so severe that blood clots can block the urinary tract and cause difficulty in urination. In a very small percentage of cases, a large amount of bleeding can cause hypotension and shock, which is difficult to treat internally and requires renal artery embolization to stop the bleeding. renal biopsies for IgA nephropathy are most commonly complicated by hematuria, but they are mostly single or of short duration. Those with persistent hypertension or small renal vasculopathy such as diabetic nephropathy, vasculitis, or amyloidosis tend to be more severe once sarcoid hematuria is complicated.
The management of sarcoid hematuria in renal biopsy wards should be treated separately according to the amount of bleeding, the primary disease and the state of renal function. Principles of dealing with the disease: absolute bed rest and braking; monitoring the changes of blood pressure and hematocrit; avoiding coughing and actions that increase abdominal pressure; increasing urine volume to prevent obstruction of ureter and urethra by blood clots; checking coagulation index and enhancing hemostasis and coagulation, but anti-fibrinolytic hemostatic agents such as aminohexanoic acid should be avoided to prevent the formation of blood clots in the urinary tract causing urinary tract obstruction. Different treatments should be used according to the degree of bleeding.
8.1.1 Hydration: If the color of hematuria is light, there is no blood clot, and the blood pressure and hematocrit are stable, the patient should be advised to drink more water or intravenous rehydration, and the color of urine should be dynamically observed. Single carnal hematuria can be left untreated, but prolong the bed rest time.
8.1.2 Conventional hemostatic drugs: bright red urine or with more blood clots indicates a large amount of bleeding, and the hemoglobin and hematocrit changes should be dynamically observed. Intravenous rehydration and vitamin K1 supplementation should be given along with other hemostatic agents. For those with pre-existing renal insufficiency with severe anemia and large blood loss, blood transfusion can be given to increase the hematocrit to help stop bleeding.
8.1.3 Posterior pituitary hormone: If the hematuria still does not stop after the above treatment, or if the bleeding volume is large, resulting in a decrease in blood pressure or a significant decrease in hematocrit, posterior pituitary hormone should be used as early as possible on the basis of the above treatment. On the basis of blood volume replenishment, the initial dose of posterior pituitary glandular lobulin can be slightly larger, 6-8U/h, and the dose is gradually reduced according to the urine color in the 2ndh, until the urine color turns completely clear and then maintained for 6-8h.
8.1.4 Selective renal artery embolization: If the bleeding is not relieved by the above measures, or if the bleeding is large, leading to hypotension and shock, and it is estimated that it is difficult to stop the bleeding with medical treatment. After performing selective renal arteriography to clarify the bleeding site, perform selective embolization to stop the bleeding.
8.1.5 Surgery: Very rarely, the kidney is removed due to renal biopsy.
8.2 Perirenal hematoma.
The vast majority of patients have no clinical symptoms, and typically present with back pain, abdominal distension, abdominal pain, abdominal distension not suitable for wanting to lumbar ribs or groin without radiation, accompanied by nausea and vomiting. Blood pressure and pulse changes and decreased hemoglobin may occur in those with heavy bleeding. If the above symptoms occur after renal biopsy, examination reveals pressure pain or swelling at the puncture site compared with the contralateral side, decreased hemoglobin, and bedside ultrasound to clarify the diagnosis and observe the size of the hematoma and assess the amount of bleeding.
8.2.1 Small perirenal hematoma: generally no special treatment is needed, bed rest is the main focus, symptomatic treatment measures such as sedation, analgesia, vitamin K1 can be applied appropriately, bleeding can stop on its own and be absorbed within 2-4 weeks.
8.2.2 No blood transfusion is needed when clinical symptoms are obvious but there is no change in blood pressure and pulse rate.
Blood transfusion is required if there is a large amount of bleeding and a drop in blood pressure.
8.2.3 Huge perirenal hematoma with significant symptoms: surgically remove the blood clot and repair the puncture break if necessary.