Surgical Therapy of Nephrolithaisis Flashcards
What imaging should you get prior to performing a PCNL?
Guideline 1: Clinicians should obtain a non-contrast CT scan on patients prior to performing PCNL (it defines stone burden and distribution, and provides information regarding collecting system anatomy, position of peri-renal structures and relevant anatomic variants) low dose is ok
What imaging may help you decide between SWL and URS?
Guideline 2: Clinicians may obtain a non-contrast CT scan to help select the best candidate for SWL versus URS (skin to stone distance < 11 cm and HU < 1000 for SWL)
If you suspect a kidney has been compromised because of nephrolithiasis, what should you do?
Guideline 3: If a clinician suspects compromise of renal function, obtaining a functional imaging study (DTPA or MAG‐3) can help guide treatment for stone disease
What tests should you order prior to surgery for nephrolithiasis?
Guideline statement 4: Clinicians are required to obtain a urinalysis prior to intervention. In patients with clinical or laboratory signs of infection, urine culture should be obtained (intra-op proximal urine and/or stone cx can also be obtained to help guide post-therapy abx)
Guideline 5: Clinicians should obtain a CBC and platelet count on patients undergoing procedures where there is a significant risk of hemorrhage or for patients with symptoms suggesting anemia, thrombocytopenia, or infection; serum electrolytes and creatinine should be obtained if there is suspicion of reduced renal function.
What is the treatment of choice for uncomplicated ureteral stones ≤10 mm?
Guideline 7: those with uncomplicated ureteral stones ≤10 mm and distal stones of similar size should be offered MET with α-blockers.
(uncomplicated patients mean pain is well controlled and there are no signs of infection or high grade obstruction)
Patients should be aware that these meds are prescribed for an off label indication
What should you do in a patient who fails MET with a ureteral stone prior to deciding on operation?
Statement 8: Clinicians should offer reimaging to patients prior to surgery if passage of ureteral stones is suspected or if stone movement will change management. Reimaging should focus on the region of interest and limit radiation exposure to uninvolved regions.
How long should you offer MET/observation for in a patient with a ureteral stone < 10 mm?
Statement 9: In most patients, if observation with or without MET is not successful after four to six weeks and/or the patient/clinician decide to intervene sooner based on a shared decision making approach, the clinicians should offer definitive stone treatment.
What should you inform patients about surgical options prior to choosing surgery for ureteral stones <10 mm?
statement 10: Clinicians should inform patients that SWL is the procedure with the least morbidity and lowest complication rate, but URS has a greater stone-free rate in a single procedure.
In patients with mid or distal ureteral stones who require intervention (who were not candidates for or who failed MET), what surgery is preferred?
Guideline 11: Clinicians should recommend URS as first-line therapy. For patients who decline URS, clinicians should offer SWL
*Of note, stone-free rates with URS for proximal ureteral stones <10 mm were superior, those for such stones >10 mm were equivalent so this guideline recommendation does not include proximal ureteral stones
In patients with suspected cystine or uric acid ureteral stones who fail MET or desire intervention, what surgery is preferred?
Guideline 12: URS is recommended
What should you not routinely do in a patient with a ureteral stone undergoing SWL?
Guideline 13: Routine stenting should not be performed in patients undergoing SWL
Following URS, when may clinicians omit ureteral stenting?
Guideline 14: Clinicians may omit ureteral stent in those without suspected ureteric injury during URS, those without evidence of ureteral stricture or other anatomical impediments to stone fragment clearance, those with a normal contralateral kidney, those without renal functional impairment, and those in whom a secondary URS procedure is not planned
Note: it doesn’t say anything about bilateral ureteroscopy….
Prior to ureteroscopy surgery for nephrolithiasis, what should you not do routinely?
Guideline 15: Placement of a ureteral stent prior to URS should not be performed routinely.
While pre-stenting is shown to improve stone free rates, the cost and QoL factors related to a stent are not deemed worth it.
What should you offer to patients to reduce ureteral stent discomfort?
Guideline 16: Clinicians may offer α-blockers and antimuscarinic therapy to reduce stent discomfort
Other options to reduce stent discomfort: bladder analgesics for dysuria, non-steroidal anti-inflammatory agents (NSAIDs), and narcotic analgesics
What should you offer In patients with large or complex ureteral stone burdens, whom neither URS nor SWL are likely to accomplish stone clearance in a reasonable number of procedures?
Guideline 17: In patients who fail or are unlikely to have successful results with SWL and/or URS, clinicians may offer PCNL, laparoscopic, open, or robotic assisted stone removal.
(PCLN is preferred, but lap and robotic surgeries are preferred over open)
If you are performing URS for a proximal ureteral stone, what scope should you use?
Guideline 18: Clinicians performing URS for proximal ureteral stones should have a flexible ureteroscope available.
Flexible URS has been shown in both prospective and retrospective studies to have high overall success rates with low morbidity/complications for < 2 cm proximal ureteral stones.
What is first-line modality for intra-ureteral lithotripsy?
Guideline 19: Clinicians should not utilize EHL as the first-line modality for intra-ureteral lithotripsy
Your options are pneumatic or laser lithotripsy
*Electrohydraulic lithotripsy (EHL) may be used safely in the renal pelvis