Urolithiasis Flashcards
Which stone?
- Radio-opaque
- Resistant to dissolution
- Most commonly caused by dehydration
Calcium oxalate
(MC type in US)
UTIs
- UTIs can decrease _____
- Hypo-_____
- Urea splitting organisms
- Proteus, Klebsiella, Pseudomonas, Serratia, Staph
- Urea–> ammonia + bicarb –> ____
- Proteus –> _____
- ureteral peristalsis
- citraturia
- struvite
- matrix stones
Which med for Prevention of Future Stones?
- Ileal resection –> decreased bile acid absorption
- Bile acids increase colonic wall permeability to oxalate –> increase oxalate absorption
- ___ binds bile acids, decreasing colon wall permeability to oxalate
Cholestyramine
Indications for Acute Intervention
- Complete or high grade _____
- Bilateral _____
- Urinary obstruction w/ ______
- Urinary obstruction in _____ kidney
- Urinary obstruction w/ rising ____
- Inability to ____ due to severe N/V
- Severe pain uncontrolled by _____
- urinary obstruction
- urinary obstruction
- urinary infection
- solitary
- creatinine
- take in POs
- analgesics
3 PE findings of urolithiasis
- Fever
- Hyperkinetic
- CVAT (costovertebral angle tenderness)
3 “relative contraindications” of ESWL
(extracorporeal shock wave lithotripsy)
- cystine stone , matrix stone
- chronic pancreatitis / pancreatic calcification
- distal obstruction
“COP”
Dissolution (chemolysis) of Struvite, Calcium phosphate stones
- Irrigation w/ _____ (___)
- acidic solution (Renacidin)
3 contraindications of Percutaneous Nephrolithotomy (PCNL)
- UTI
- Coagulopathy
- No percutaneous renal access
(CUN)
ESWL (extracorporeal shock wave lithotripsy)
- Done under ____
- Done w/ _____ imaging
- if radio-opaque, ____
- if radiolucent, _____
- Shock wave generator positioned where?
- Table manipulated to put stone in ____
- Shocks delivered ___-___/ minute
- Gated w/ ___ to avoid inducing dysrhythmia
- sedation/anesthesia
- fluoroscopic imaging
- easily seen
- put up a stent and inject contrast dye
- against patient’s side
- cross-hairs
- 60-90
- EKG
4 etiologies of metabolic urolithiasis
- Hypercalciuria
- Hypocitrauria
- Hyperoxauria
- Hyperuricosuria
Which stone?
- Radiolucent
- Forms in acidic urine (<6.0)
- Dissolves in alkalinized urine
Uric acid (urate)
- Malingering pts know this stone does not show up on x-ray. But will show up on CT
6 meds to prevent future stones
- potassium citrate (raises pH & citrate level)
- thiazide
- allopurinol
- pyridoxine (B6)
- Cholesyramine
- Thiols
Which med for Prevention of Future Stones?
- decreases uric acid levels
- Only decreases stone incidence if pt had been hyperuricosuric*
Allopurinol
Which med for Prevention of Future Stones?
- Corrects acidosis
- Increases reabsorption of Ca into kidneys, decreasing urine calcium excretion
- Can worsen stone disease, if it causes hypokalemia**
- May be given w/ potassium**
- 2 SE?
Thiazide
- weakness & fatigue
5 contraindications of ESWL (extracorporeal shock wave lithotripsy)
- pregnancy
- coagulopathy
- UTI
- Renal Artery Aneurysm
- AAA
“U CRAP”
Prevention of Future Stones
- Fluid intake, should result in a urine volume of ___ L
- Encourage fluids w/ _____ , Discourage ____.
- Low sodium (less urinary Ca, more urinary citrate)
- Low ___ protein intake (amino acid effect)
- Low oxalate
- Moderate Ca intake
- Avoid high doses of vit __ and ___
- 2.5
- citrate / soda
- animal
- C & D
What is the most common type of stone in the US?
Calcium oxalate
Which stone?
- associated w/ UTI & laxative abuse
- Radiolucent
Ammonium Acid Urate
4 complications of PCNL (percutaneous nephrolithotomy)
- bleeding
- sepsis
- renal pelvis perforation
- pneumothorax / hydrothorax
Which stone?
- Genetic defect, autosomal _____
- Heterozygotes usually _____
- Homozygotes usually ______
- Caused by _____
- Dissolved in ____ environment
Cystine
- recessive
- hetero –> NOT stone formers
- Homo –> form stones
- cystinuria
- alkaline
Tx of upper tract stones (2 locations?)
- 6 tx options
kidney & ureter
- Trial of passage
- Extracorporeal Shock Wave Lithotripsy (ESWL)
- Dissolution
- Open or laparoscopic surgery
- Ureteroscopy w/ stone manipulation
- Percutaneous Nephrolithotomy (PCNL)
(TED UOP)
Tx of Urolithiasis
- Abx for infection
- Acute tx to relieve obstruction:
- _____
- ______
- (to prevent sepsis / renal damage / loss of renal function)
- Later proceed to definitive stone management under more controlled circumstances
- ureteral stent placement
- nephrostomy tube placement
ESWL
- Decrease ____ function up to 3 weeks
- 6 complications?
- renal perfusion
- renal hematoma / retroperitoneal hematoma
- Ecchymosis
- UTI –> sepsis
- Steinstrasse
- Ureteral stricture
- Pain
3 components of evaluation of urolithiasis
- H&P
- Labs (creatinine and white count)
- Imaging (Stone protocol CT WITHOUT contrast)
Which tx?
-
Indications: failure of / contraindications to other modalities
- trial of passage
- dissolution
- ESWL
- Ureteroscopy w/ stone manipulation
- PCNL
Open or Laparoscopic Surgery
(not common, is usually last resort)
Which 7 meds can cause urolithiasis?
- Vit C
- Vit D
- Triamterene precipitation
- Protease inhibitors (Indinavir)
- Furosemide increases urinary calcium excretion
- Acetazolamide (CAI) causes RTA state
- Uricosuric agents (probenecid, salicylates)
5 imaging studies
- KUB (Kidney, Ureter, Bladder)
- US abdominal / retroperitoneal / renal & bladder
- Intravenous Urogram (IVU) (not performed anymore)
- CT Stone Protocol (abd/pelvis) WITHOUT contrast
- CT urogram (abd/pelvis) WITH contrast, including delayed phase
(if stone protocol is negative, get the CT urogram)
What are the 2 causes of stones due to anatomy?
- Obstruction
- Stasis
Which stone?
- Precipitated drug, such as _____
- Radiolucent
- Not visible on stone-protocol CT
Protease Inhibitor Stone
- Indinavir
A few etiologies of Urolithiasis (8)
- Anatomic
- Urine characteristics
- Pt volume status
- Diet
- Metabolic
- Disease states
- UTI
- meds
5 components of metabolic eval to prevent future stones
- H&P
- UA
- Stone analysis
- Serum labs (electrolytes, uric acid, Ca, phosphate, alkaline phosphatase, creatinine)
- 24 hour urine collection
Candidates for “trial of passage”
- Stones __mm or less (68% pass within __ days)
- Taking fluids and analgesics PO
- Alpha-blocker (___) increase passage percentage, decrease time to passage, decrease pain w/ passage
- Filter urine (screen / coffee filter)
- Periodic imaging to assess for ____.
- 5
- tamsulosin
- hydronephrosis
Which med for Prevention of Future Stones?
- Involved in metabolism of oxalate
- Deficiency leads to hyperoxaluria
Pyridoxine (B6)
ESWL
- If bilateral stone disease, may choose to do what?
- If solitary kidney, use what?
- To do each kidney at separate settings
- ureteral stent
Percutaneous Nephrolithotomy (PCNL)
- Access achieved in ____ or ____
- Access through the ____, ____ approach, needle placed under ____ guidance
- Needle/catheter advanced to ______
- Wire, tract dilation
- Nephroscopy
- Instruments passed under direct ___
- Energy delivered to ______
- _____ grasped, removed
- Interventional Radiology or OR
- skin / flank / fluoroscopic
- renal collecting system
- vision
- lithotripsy stone
- fragments
4 sxs of urolithiasis
- Flank pain
- N/V (from the pain)
- Hematuria
- Hyperkinetic** (common). Pt is moving all over and pacing the room
9 Complications of Ureteroscopy w/ manipulation (endoscopy)
- Ureteral ____
- Ureteral ____
- Submucosal ____
- Ureteral ____ (1%)
- Extrustion of stone outside the lumen of ureter
- ____
- ____
- _____
- Avulsion
- perforation
- tunneling
- stricture
- UTI
- Bleeding
- Pain
Tx of lower tract stones (2 locations?)
- 4 treatments?
Bladder & urethra
- Cystourethroscopy, cystolitholapxy
- Extracorporeal shock wave lithotripsy (ESWL)
- Open stone removal (super rare!)
Dissolution (meds) - common tx
3 components of volume status of pt w/ Urolithiasis
- Volume depletion
- Low UOP
- Supersaturation of solute
Which med for Prevention of Future Stones?
- Tx for cystinuria
- Increases solubility, prevention of cystine stones
- Tiopronin
- D-Penicillamine
Thiols
Other 5 names for Urolithiasis
- “kidney stones”
- nephrolithiasis
- ureterolithiasis
- cystolithiasis
- calculus / calculi
3 labs
- UA (pH, specific gravity, hemoglobin, microscopy)
- CBC (WBC elevation)
- BMP (creatinine, BUN, electrolytes)
Dissolution (chemolysis) of Uric Acid Stones
-
Alkalinize urine
- pH greater than ___
- __ and ___ PO
- Can take __ months to work
-
Irrigate collecting system
- via _____
- sodium bicarb
- THAM
- 6.5
- Sodium bicarb & Potassium citrate
- 3
- nephrostomy tube
What are the 2 Crystal Inhibitors?
- Citrate (complexes w/ calcium)
- Urea (increases solubility of uric acid)
Which tx?
- Done in OR under general anesthesia
- Transurethral approach
- Flexible scope placed up ureter
- Energy delivered to calculus
- laster lithtripsy
- ultrasonic lithotripsy
- electrohydraulic lithotripsy (EHL)
- Pneumatic impactor “_____”
- Stone broken up
- Fragments basketed out
- Possible ____ temporarily
Ureteroscopy w/ stone manipulation
- “jackhammer”
- ureteral stent
Prevention of Future Stones
- Reduce ____
- High ____ lowers urinary citrate
- Animal protein
- Limit intake of ____ and _____
- ____ and _____: low ______
- PRAL (potential renal acid load)
- PRAL
- cheese & egg yolks
- fruits & veggies
What 2 things = emergency?!
- Fever
- Obstructive stones
Extracorporeal Shock Wave Lithotripsy
- 3 good things about ESWL
- 1 bad thing about ESWL
- Outpatient
- Non-invasive
- Sedation
- Bad: stone fragments not removed
Which med for Prevention of Future Stones?
- Corrects acidosis, which increases urinary citrate and decreases urinary calcium
- Binds w/ calcium, inhibits calcium crystallization
- SE: hyperkalemia** & peptic ulcers
- Caution: Uncontrolled DM, renal insufficiency, delayed gastric emptying, K sparing diuretics
- Dosing: titrate per urine pH
Potassium Citrate
Which stone?
- Cause: UTI
- Radio-opaque
- Forms in alkaline urine
- Can be dissolved w/ acidification of urine
- Composition of most ______
Magnesium ammonium phosphate (struvite, triple phosphate, MAP)
- staghorn calculi
Dissolution (chemolysis) of Cystine Stones
-
Alkalinize urine
- pH greater than __
- ____ PO
-
Irrigation of collecting system
- Sodium bicarb
- THAM
- N-acetylcysteine
- 7.5
- Potassium citrate
Which stone?
- Associated w/ Proteus UTI
- Radiolucent
Matrix
ESWL (extracorporeal shock wave lithotripsy)
- Stone size < __ cm
- Visible on ____
- 2
- fluoroscopy
4 types of Open / Laparoscopic Surgery
- Cystolithotomy (large stone burden, other concomitant surgery)
- Pyelolithotomy
- Ureterolithotomy
- Anatrophic nephrolithotomy (Brodel’s avascular plane)
