Download to read offline
More Related Content
Similar to Abdu Seminar on Ob Uropathynnnnnnn.pptx
More from mekuriatadesse
Abdu Seminar on Ob Uropathynnnnnnn.pptx
- 1. Seminar On UrinaryTract Obstruction (Obstructive Uropathy) Presenter Dr Abdurazak (R3) Moderator Dr Tadele (Urologist) 08-Dec-21 1
- 2. Outline • Objective • Introduction •Prevalence • Classification • Causes • Pathophysiology • Hemodynamics • Diagnosis • Management • Summary 08-Dec-21 2
- 3. Objective • To definethe spectrum upper UTO and outline its burden. • Describe how to approach a patient with upper UTO. • Discuss the management principles of common causes of upper UTO. 08-Dec-21 3
- 4. Introduction • UTO isdefined as an interruption of urine flow at some point from renal tubules to urethra. • Increases pressure within urinary tract causing structural and physiologic changes. • Can lead to mild and transient to permanent renal injury – Uropathy and /Or Nephropathy • Can be as proximal as the calyces and as distal as the urethral meatus • The degree of injury and overall renal function depends on 08-Dec-21 4
- 5. Prevalence • Obstructive Uropathyaccounts for 10% of all cases of renal failure. • Obstruction of the urinary tract can occur at any age • In children males are more affected than females age. • Hydro nephrosis reported in 3.1% of individuals (autopsy series). • Hydro nephrosis common in women(20-60yr) and men (>60yrs) 08-Dec-21 5
- 6. Classification • Congenital orAcquired • Acute or Chronic • Complete or Partial • Unilateral or Bilateral • Upper or Lower • Benign or Malignant 08-Dec-21 6
- 7.
- 8. Pathophysiology Effects of obstructiveUropathy depends on:- • Degree of obstruction (partial or complete) • Extent of obstruction (unilateral or bilateral) • Chronicity (acute or chronic) • Infection • Presence of anomalies 08-Dec-21 8
- 9. Physiologic parameters thatwill be affected following obstruction:- • Renal hemodynamics • Glomerular filtration • Tubular function • Anatomic changes 08-Dec-21 9
- 10. Gross Pathologic Findings After42 hours: • The ureter and renal pelvis dilate • Blunting of renal papilla • Increase kidney weight due to edema At 7th day: • Collecting system dilation, edema and renal weight further increase. At 12th day: • Pelvi calyceal dilation increase further. At 21 to 28 days: • The cortex and medullary tissue get diffusely thinned. 08-Dec-21 10
- 11. Microscopic Pathologic Findings At42 hours: - Lymphatic dilation and interstitial edema. At 7th day: Duct and tubular dilatation will be prominent. Widening of Bowman space, Tubular basement membrane thickening. At 12th day: Papillary tip necrosis, Regional tubular destruction, Week 5-6 Widespread glomerular collapse and tubular atrophy, interstitial fibrosis, and proliferation of connective tissue in the collecting system 08-Dec-21 11
- 12. Hemodynamic Changes Different inunilateral and bilateral obstruction. 1. Unilateral Ureteral Occlusion Has three phases:- Phase I: • Occurs in the first 1-2 hours. • RBF increases • High PT and collecting system pressure because of the obstruction. Phase II: • After 3 to 4 hours. • Pressure parameters remain elevated • But RBF begins to decline. Phase III: • Begins about 5 hours after obstruction. • It is characterized by a further decline in RBF • Paralleled by a decrease in PT and collecting system pressure 08-Dec-21 12
- 13. 2. Bilateral UreteralOcclusion Only modest increase in RBF. Lasts shorter (approximately 90 minutes) Prolonged and profound decrease in RBF. The ureteral pressure remains elevated for at least 24 hours. Glomerular filtration and RBF remain depressed after release of BUO 3. Partial Ureteral Occlusion Renal hemodynamics and in tubular function occur slowly. Thus partial neonatal obstruction can impair nephrogenesis. 08-Dec-21 13
- 14. Hemodynamic and GFRChanges 08-Dec-21 14
- 15. Effects on TubularFunction • Decreased urine concentrating ability and polyuria. • Decreased Na+ ion reabsorption. • Decreased K+ secretion in UUO but increased Secretion in BUO. • Decreased urinary acidification. • Other cations and anions:- – Phosphate excretion is increased in BUO while retention in UUO. – Magnesium excretion is markedly increased after the release of either UUO or BUO. 08-Dec-21 15
- 16. Approach - Diagnosis History Asymptomatic Symptoms: Variabledepending on site, duration and degree of obstruction – Flank pain – Nausea or vomiting – Hematuria – Recurrent UTI – Fever and Chills – New-onset or poorly controlled hypertension – Recent gynecologic or abdominal surgery – Anuria – Pain after increased fluid intake - flank pain after alcohol ingestion in unilateral PUJO or UVO 08-Dec-21 16
- 17. Physical Examination • Bloodpressure (hypertension) • Signs of dehydration and intravascular volume depletion • Peripheral edema,, signs of congestive heart failure. • Palpable kidney or bladder • Enlargement of pelvic organs (eg. Prostate, uterus) • Examination of external urethra for phimosis, meatal stenosis 08-Dec-21 17
- 18. Work Up Laboratory Studies •Urinalysis • Renal Function Test • Fractional Excretion of Sodium • Serum electrolyte 08-Dec-21 18
- 19. Diagnostic Imaging Ultrasound Important tomake anatomic diagnosis: • Renal size • Cortical thickness • Cortico medullary differentiation, • Grade of collecting system dilation (Hydronephrosis) 08-Dec-21 19
- 20. Computed Tomography – Goldstandard for renal stone disease. – Has a sensitivity of 96% and specificity of 100%. – Non contrast CT for patients presenting with acute flank pain – Contrast-enhanced CT gives detailed anatomic and functional information. 08-Dec-21 20
- 21. Excretory Urography • Providesboth anatomic and functional information. • Largely replaced by CTU. Should not be used in:- • Patients with contrast allergy • Renal insufficiency • In pregnant women 08-Dec-21 21
- 22. Retrograde Pyelography/Antegrade Pyelography •Used for: asses exact site of obstruction – Adequately define collecting system anatomy – Patients with renal insufficiency or – Patients who are un able to take i.v contrast – If emergency decompression of UPJO is required – If infection is present 08-Dec-21 22
- 23. Magnetic Resonance Urography •Avoids radiation exposure. • Gives both anatomic and functional information. • Has 100% sensitivity in diagnosing upper UTO. The protocol involves: • T1 and T2 weighted imaging with out contrast • Then administering Godalinium based contrast 08-Dec-21 23
- 24. Nuclear Renography – Providesnon invasive information about dynamic renal function. – Also known as diuretic renography/MAG3 scan. • Differentiate obstructive vs. non obstructive hydronephrosis. • Limited anatomic information 08-Dec-21 24
- 25. Treatment of RenalObstruction General Measures – Acute Phase Treatment Pain management • NSAIDs • OPIOIDS • calcium channel blockers Renal Drainage Percutaneous nephrostomy (PCN) – Important in draining purulent content – Allows urine output measurement – Avoid ureteral manipulation – Decrease risk of sepsis. – Radiographic study Ureteral stenting – Patient comfort – Lower risk of bleeding 08-Dec-21 25
- 26. Temporary drainage procedures -Complete obstruction , Unilateral vs Bilateral - Obstruction with infection - Obstruction with acute renal failure - Obstruction in a Solitary native Kidney - Obstruction in a renal allograft - Obstruction in a Pregnant female - ** Uncontrollable fever ,flank pain or gastro intestinal complaints, older , debilitated 08-Dec-21 26
- 27. Treatment of RenalObstruction Definitive Management • Depends on: – The cause – The function of affected kidney – The status of contra lateral kidney – Age of the patient Management of post obstructive diuresis. – Treatment is commonly required:- • For pathologic post obstructive diuresis. • If there is altered mental status, electrolyte abnormality and signs of fluid overload – Monitoring (V/S, serum e-, urine output and osmolality) – Limit intravenous fluid (0.45% normal saline) , 0.5 cc NS/1 cc Urine 08-Dec-21 27
- 28. Indications of ImmediateDefinitive Mx • Partial obstruction by Stones • Emphysematous pyelonephritis with obstruction - Nephrectomy 08-Dec-21 28
- 29. Common Causes OfUpper UTO Urolithiasis Ureteropelvic junction Obstruction. Ureteral stricture Retroperitoneal fibrosis Retrocaval Ureter 08-Dec-21 29
- 30. Ureteropelvic junction Obstruction(UPJO) • Refers significant impairment of urinary transport from the renal pelvis to the ureter. • Boys are more commonly affected girls • Common on the left side and bilateral in 10% of cases. 08-Dec-21 30
- 31. Etiology of UPJO Congenital(intrinsic disease) – Aperistaltic segment of the ureter – Ureteral valves/kinks – ureteral stricture – “Aberrant” vessels Acquired – Stone disease – Post operative or inflammatory stricture – Urothelial neoplasm – Polyps 08-Dec-21 31
- 32.
- 33. Management of UPJO Indicationsfor intervention 1. Presence of symptoms associated with obstruction 2. Impairment of overall or ipsilateral renal function 3. Development of stone or infection 4. Hypertension Goal of intervention: – Relief symptoms – Preserve or restore renal function. 08-Dec-21 33
- 34. Management 1. Conservative • Principlesof conservative management –Observation of asymptomatic hydronephrosis will resolve spontaneously. Patient needs careful observation with regular renal scan - Acute Management 2. Surgical Intervention 08-Dec-21 34
- 35. Options for Intervention Openpyeloplasty Laparoscopic/robotic pyeloplasty Endoscopic pyeloplasty Nephrectomy Basic principles • Reconstruct widely patent UPJ • Provide water tight anastomosis • Allow funnel shaped transition between the pelvis and ureter. 08-Dec-21 35
- 36. Dismembered Pyeloplasty/Anderson HynesPyeloplasty Advantage – Can be used regardless of the site of ureteral insertion – Allows reduction of redundant pelvis and straightening of tortuous ureter. – Anterior and posterior transposition of the UPJ is possible. – Excision of anatomically and functionally abnormal UPJ. Disadvantage – Not suited for long or multiple proximal ureteral stricture. – UPJ obstructions associated with small intra-renal pelvis. 08-Dec-21 36
- 37. Operative Technique Flank Approach: –It is common and familiar for most urologists. 1. Positioning • Straight flank position 2. Skin incision • Flank incision 3. Exposure • Involves separation of three muscle/fascial layers and opening transversalis fascia. 08-Dec-21 37
- 38. Operative Technique 4. Identifythe ureter and aberrant vessel (if any) • The ureter is identified distal to the UPJ and cleaned of investing fat and fascia. 5. Apply marking suture on the lateral aspect of the ureter below the narrowing 08-Dec-21 38
- 39. Operative Technique 6. Ureteropelvicjunction is excised. 7. The lateral aspect of ureter is spatulated. 8. Anastomosis the lateral part with inferior and the medial part with superior part of pelvis 08-Dec-21 39
- 40.
- 41. Reduction pyeloplasty • Isperformed when the renal pelvis is exceptionally redundant 1. Excise redundant portion of the pelvis 2. Close the cephalad portion of the renal pelvis down to the dependent part. 3. Anastomose the dependent portion with the ureter 08-Dec-21 41
- 42. PUJ Transposition • Isdone for aberrant or accessory lower pole vessel. 08-Dec-21 42
- 43. Non-dismembered Reconstructive Procedures •Mostly replaced by dismembered pyeloplasty • Indicated in: – High insertion of the ureter – Long and more distal obstructions. • Commonly performed non Anderson Hynes procedure include: 1. Foley Y-V plasty 2. Culp-DeWeerd Spiral Flap 3. Scardino-Prince Vertical Flap 08-Dec-21 43
- 44. Foley Y-V plasty •Indicated in UPJO secondary to high ureteral insertion. • Contraindicated when there is crossing vessels and redundant renal pelvis. • Operative technique i. Outline the flap with tissue marker or sutures ii. Develop a V flap with its base directed to the dependent portion of the pelvis and bring the apex of the flap to the stem of Y incision. iii. Approximate the posterior wall iv. Complete the anastomosis by approximating anterior wall. 08-Dec-21 44
- 45. Culp-DeWeerd Spiral Flap •Suited for large readily accessible extra renal pelvis and long segment narrowing . • Operative technique i. Outline the spiral flap with the base directed obliquely on the dependent aspect. ii. The flap is developed and medial line of incision is extended down. iii. The apex is rotated down to the most inferior aspect of the ureterotomy. iv. Anastomosis is done over an internal stent 08-Dec-21 45
- 46. Scardino-Prince Vertical Flap •Used when dependent UPJ is situated at medial margin of large “box extra renal pelvis” 08-Dec-21 46
- 47. Laparoscopic pyeloplasty • Hassimilar indication as open or endo urologic pyeloplasties. • Comparable outcome with open pyeloplasty (94% success rate) • Not suited for PUJ obstructions with crossing vessels. 08-Dec-21 47
- 48. Endo-pyelotomy • Is lessinvasive procedure. • It involves balloon dilation or incision with hot wire of narrowed UPJ. • Not suited for PUJ obstructions with crossing vessels. • Can be:- – Anterograde pyelotomy or – Retrograde pyelotomy • Lower success rate (73%) • Contraindications are:- – Long segment obstruction – Coagulopathy – Active infection. 08-Dec-21 48
- 49. Ureteral Stricture Incidence inthe general population is unknown. 08-Dec-21 49
- 50. Diagnostic Studies andIndications for Intervention Diagnostic studies: CT scan Antegrade and retrograde pyelogram CT urography/Diuretic renography Ureteroscopy and biopsy Indication for intervention Symptoms like pain Recurrent UTI Ongoing obstruction Need to rule out malignancy. 08-Dec-21 50
- 51. Options of Intervention Endoscopicintervention: • Endoscopic stenting • Balloon dilation • Endoscopic ureterotomy Surgical repair 08-Dec-21 51
- 52. Endoscopic stenting • Effectivein acutely treating intrinsic stricture. • Has a success rate of 88% in intrinsic obstruction. • Eventual compression is common if it is used for external compression. • Best suited for patients: – With poor prognosis and – Patients who are not candidate for surgical intervention. 08-Dec-21 52
- 53. Balloon Dilation • Indicatedin functionally significant obstruction. • Contraindication for balloon dilation are: – Presence of active infection – Stricture segment longer than 2cm. • It can be: – Retrograde approach (initial intervention) – Antegrade (done when retrograde approach fails) • Ureteral stent is left in place for 2-4 weeks after initial dilation. 08-Dec-21 53
- 54. Endoureterotomy Endo luminalureteral incision is a logical extension of balloon dilation. It is performed under direct vision using ureteroscopic control. Approach can be : – Retrograde: preferred and is less invasive. – Antegrade : is done if nephrostomy tube already exist. – Combined method The site of ureteral incision depends on the location of the stricture: – Anteromedial incision in lower ureteral stricture – Lateral or posterolateral incision for proximal ureteral 08-Dec-21 54
- 55.
- 56.
- 57. Ureteroureterostomy • Indicated forshort segment involving the upper and mid ureter. • Incision depends on level of stricture (flank incision is commonly used) • Tension free anastomosis to avoid stricture. • Operative techniques – Mobilize proximal and distal ureters – Spatulate both ends (180* apart) – Place a suture and E-to-E ureteroureterostomy • Double J stent left for 4-6 wks 08-Dec-21 57
- 58. Ureteroneocystostomy • It refersto reimplantation of the ureter into the bladder. • Is appropriate for obstruction or injury in the distal 3-4cm of ureter . • Approach:- –Open • Pfannenstiel or • Lower midline incision. –laparoscopic • Modification with Boari flap or Psoas hitch may be necessary. • Ureteral stenting is typically required in open surgery. 08-Dec-21 58
- 59. PSOAS HITCH • Forthe lower third of the ureteral defect. • Done when direct reimplantation not possible. • Indications:- – Distal ureteral stricture, injury – Failed ureteroneocystostomy • Contraindication:- – Small bladder with limited mobility • Urodynamic studies to estimate the bladder capacity is required. 08-Dec-21 59
- 60. • The ipsilateralureter is identified mobilized, and divided just above the diseased segment. • Bladder is mobilized by freeing its peritoneal attachments. • Anterior cystotomy created. 08-Dec-21 60
- 61. • The ureteris delivered into the bladder and tension free anastomosis made. • The ipsilateral bladder dome is secured to the psoas muscle. 08-Dec-21 61
- 62. • Complications:- – Persistenturine leak – Uro-sepsis – Ureteral obstruction – Nerve injury, bowel injury, iliac vessel injury • The success rate of uretero-neocystostomy with a psoas hitch is greater than 85%. 08-Dec-21 62
- 63. BOARI FLAP • Preferredmethod when stricture is too long or limited ureteral mobility • It can bridge a 10- to 15-cm ureteral defect, • Conditions affecting bladder compliance should be treated first. • Outcome is good if well vascularized flap is created. • Commonest complication –recurrent stricture 08-Dec-21 63
- 64. Salvage Procedures RENAL DESCENSUS •Involves mobilizing the kidney and rotating it inferiorly and medially. • It used to bridge upper ureteral defects and to allow tension free anastomosis • Lower pole secured to retroperitoneal muscles. • Up to 8 cm of additional length may be gained. • It can be combined with Boari flap in case of pan ureteral stricture. 08-Dec-21 64
- 65. Transureteroureterostomy • Ureteral lengthis insufficient to reach bladder • Contraindications: – Absolute contraindications: • In adequate donor ureter length • Diseased recipient ureter – Relative contraindications: • Nephrolithiasis • Retroperitoneal fibrosis • Urothelial malignancy • Chronic pyelonephritis, and • Abdominopelvic radiation 08-Dec-21 65
- 66. Ileal-Ureteral Substitution • Doneonly when other methods are not possible and bladder is not suitable for reconstruction. • Proximal anastomosis could be at the level of renal pelvis or ileocalycostomy. • Contraindicated: – If baseline Cr>2mg/dl – If there is bladder outlet obstruction – Inflammatory bowel disease – Radiation enteritis. • Complications include – Urine leak – Urinoma – Obstruction – Metabolic – Renal insufficiency 08-Dec-21 66
- 67. RETROPERITONEAL FIBROSIS • Characterizedby the presence of inflammatory and fibrous retroperitoneal tissue. • True incidence is unknown. • Commonly affects patients between the age 40 to 60. • Male-to-female ratio 2:1 to 3 :1. • It is idiopathic in 70% of cases. • In around 30% of cases RPF is associated with: • Drugs • Malignancy • Radiation • Infectious causes 08-Dec-21 67
- 68. Diagnosis • History – Backor flank pain – Other non specific symptoms • Physical examination: – Usually unremarkable • Laboratory findings: – Elevated WBC, ESR, CRP – Renal insufficiency and electrolyte abnormality • Imaging – CT scan and CT urography • Biopsy (rarely needed) 08-Dec-21 68
- 69. Management 1. Initial management –Decompression (PCN or ureteral stent) • For patients with Hydronephrosis and uremia. – Stop inciting drug (if any) – Work up for the cause. 2. Medical mangement – Steroids – Immunomodulators (azathioprine, cyclophosphamide, cyclosporine, colchicine) 3. Surgical management – Ureterolysis (open or laparoscopic) 08-Dec-21 69
- 70. Recovery • GFR recoveryAfter relieve Of UUO – 100 % after 7 days , 70 % after 14 days , 30 % after 4 weeks, No recovery after 6 weeks. 08-Dec-21 70
- 71. Summary • High indexof Suspicious is mandatory • Through evaluation • Imaging • On Time Management • Follow Up 08-Dec-21 71
- 72.
- 73.
Editor's Notes
- #5 - The degree of injury and overall renal function depends on: partial or complete, acute or chronic ,level of obstruction, base line condition of kidneys, infection or no infection, congenital anomalies
- #6 Any age – fetal development , Children and Adults Hydronephrosis – suggests for UTO but not definitive for. E.g VUR disease. 60 years women Hydronephrosis , Pregnancy and gynecology, Men > 60 years ,prostatic Cancer
- #7 Severity , management , Outcome and Prognosis OF UTO Intrinsic or Extrinsic Intra or Extra luminal
- #9 1. Gross 2. Microscopis 3. Histologic changes that are bounded by times Obstruction less 1 week ,complete recovery of GFR. No recovery after 12 weeks of obstruction
- #11 - After 6 weeks, the obstructed kidney is enlarged with a cystic appearance, but lower weight, as compared with the normal contralateral kidney. The histologic derangements associated with early obstruction are Localized primarily to the tubulointerstitial compartment of the kidney and Include massive tubular dilation, progressive tubulointerstitial fibrosis, inflammatory cell infiltration, and apoptotic renal tubular cell death. Although the glomeruli of the kidney are relatively spared, damage to the tubulointerstitial compartment of the kidney is severe
- #12 Week 3 Severe tubular loss, proliferation of fibroblasts, and collagen deposition
- #13 - Laterality also important. Triphasic – three phases
- #16 The onset of concentration defects may develop soon after obstruction (6 minutes). Causes could be decrease hypertonicity of medullary interstitium, development of vasopressin resistance, ischemic damage to the nephrons or decreased expressions of AQP1, AQP2, and AQP3. Decreased Na+ ion reabsorption which results from decreased transporter at the apical (Na+,K+,2Cl− cotransporter) and basolateral (Na+,K+-ATPase) sides of the tubeles. Decreased K+ secretion in UUO results from decreased glomerular filtrate delivery to the tubules minimizing transmembrane gradient or intrinsic defect in K+ secretion. In BUO increased K+ secretion results from increased delivery of Na+ to DCT acting as a stimulus for K+ secretion. Decreased urinary acidification due to defects in H+-ATPase or H+,K+-ATPase, Cl−/HCO3 − exchange, a back leak of protons into the renal interstitium, or failure to generate a satisfactory transluminal electrical gradient. Wang and colleagues (2008b) showed that the urinary acidification defect and metabolic acidosis after release of BUO correlated with reduced expression of the Na+/H+ exchanger (NHE3) in the cortex, reduced electrogenic Na+/HCO3 − cotransporter (NBC1), the electroneutral Na+/HCO3 − cotransporter (NBCn1) and the anion exchanger, pendrin. Magnesium excretion is markedly increased after the release of either UUO or BUO. The increase most likely results from compromised transport in the thick limb of the Henle loop, which is related to ischemia.
- #17 - UTO is important to recognize since it is readily reversible if quickly corrected. - Hydronephrosis may present either as an incidental finding on an ultrasound or CT done because of nonspecific symptoms, Severe flank pain suggests a more acute onset of obstruction and, if very sudden in onset, a ureteric stone may be the cause. Pain induced by a diuresis (e.g., following consumption of alcohol) suggests a possible UPJ obstruction “Dietl’s crisis”. Anuria (the symptom of bilateral ureteric obstruction or complete, obstruction of a solitary kidney) - ** high suspicious of Obstructive Uropathy- new onset HTN and pt with Renal failure without Hx renal d/o , DM and HTN, Recurrent UTIs - Acute pain – stretching of collecting system, unrelenting ,excruciating pain radiating to , + NV Chronic - less pain , asymptomatic, after fluid intake - Duration, type of pain, surgical and medical Hx, family Hx, smoking Ostructive uropathy are so variable, the diagnosis depends on prompt and appropriate imaging. Hydronephrosis with out obstruction = VUR,Pregnancy , high urine out put state Palpable flank mass in infants – PUJO True Urologic Emergency – infected UPJO Anuria a:- complete , bilateral or Solitary kidney Obstruction
- #18 The urinalysis can provide an estimation of osmolality , evidence of urinary tract infection, insight into stone formation based on crystals that may be present in the urine, and the possible presence of medical renal disease with the presence of Protein and/or cellular casts. Cystatin C has recently emerged as a more accurate marker of GFR and can be used in modified CKD-EPI and Schwartz equations to estimate GFR, In general, a GFR greater than 90 mL/min/1.73 m2 is considered normal, between 60 and 90 mL/min/1.73 m2 is considered a mild decline in renal function, between 30 and 60 mL/min/1.73 m2 is a moderate decline in renal function, between 15 and 30 mL/min/1.73 m2 Is a severe decline in renal function, and less than 15 mL/min/1.73 m2 is consider renal failure
- #19 The urinalysis can provide an estimation of osmolality , evidence of urinary tract infection, insight into stone formation based on crystals that may be present in the urine, and the possible presence of medical renal disease with the presence of Protein and/or cellular casts. Cystatin C has recently emerged as a more accurate marker of GFR and can be used in modified CKD-EPI and Schwartz equations to estimate GFR, In general, a GFR greater than 90 mL/min/1.73 m2 is considered normal, between 60 and 90 mL/min/1.73 m2 is considered a mild decline in renal function, between 30 and 60 mL/min/1.73 m2 is a moderate decline in renal function, between 15 and 30 mL/min/1.73 m2 Is a severe decline in renal function, and less than 15 mL/min/1.73 m2 is considered renal failure FENa > 4 % -----Post renal Obstructions CBC HCG
- #20 Although it is primarily an anatomic study, Doppler modifications may add a functional component. There is no associated ionizing radiation, and it is thus considered safe in pediatric and pregnant patients. Doppler ultrasonography allows measurement of the renal resistive index (RI), which has been used to assess for obstruction. The RI is defined as peak systolic velocity (PSV) minus the end-diastolic velocity (EDV) divided by the PSV. In a pooled analysis, ultrasound was demonstrated to have only a 45% sensitivity and 94% specificity in detecting ureteral stones and a 45% sensitivity and 88% Specificity in detecting renal calculi as compared with non contrast CT. Initial imaging for Obstructive Uropathy – U/S , CT scanning U/A and Microscopic analysis :- UTI, stone formation, Crystals ,evidence of medical renal diseases, FENa>4% postrenal ARF ( BOO, BUO) Hyperkalemia – Elevated Cr, Acidosis and Hyperkalemia – may suggest BUO or obstructed Solitary kidney See campbel p.1094 on U/S Anatomic Assemenent - U/S ( kidney , ureter,bladder) – non invasive, non radiation – pregnant and pediatrics age , preferred for renal failure and contrast allergy - Detect crossing vessels , doppler U/S RI, thinning of renal parenchyma , echodebric sedements - Renal resistive index increase sensitivity Non contrast CT scan – emergency evaluation of of flank pain and obstructive anuria - Best for Renal colic or ureteric colic evaluation – also LN, RPF, CA except - indinavir and completely uncalcified matrix stones ureteral dilatation, nephromegaly, - Decreased parenchymal density of the involved kidney (compared with other kidney) and perinephric stranding or fluid
- #21 Secondary CT signs of obstruction such as ureteral dilatation, nephromegaly, decreased parenchymal density of the involved kidney as compared with the contralateral renal unit, perinephric stranding, or fluid can facilitate the diagnosis of acute obstruction NCHCT - Can detect most radiolucent stones
- #22 Acute urinary obstruction may be inferred from the functional abnormality of a delayed nephrogram and pyelogram on the affected side or sides. Delayed images may then ultimately reveal the anatomic level of obstruction and perhaps causation. In addition, other signs may be present that may indicate chronicity of obstruction such as parenchymal thinning, extreme calyceal blunting, and ureteral tortuosity
- #23 Retrograde pyelography refers to the injection of contrast into the upper collecting system through a cystoscopic approach. The technique accurately defines ureteral and upper collecting system anatomy and can determine the location of an obstructive lesion. Antegrade pyelography is most often used when retrograde pyelography is not technically feasible or when other imaging studies do not adequately define the collecting system
- #24 The MRU measurement of contrast excretion is the renal transit time (RTT), which is defined as the time it takes for contrast to pass from the renal cortex to the proximal ureters. It is classified as normal if it is 4 min or less, equivocal if between 4 and 8 min, and obstructed if 8 min or longer. Major dis advantages of MRU includes: 1. availabltiy 2. cost 3. poor sensitivity in identifying stone disease and 4. Nephrogenic systemic fibrosis (specially in patients with renal function impairment.) Figure: Magnetic resonance urography image showing right ureteropelvic junction obstruction.
- #25 - A nuclear renogram is performed by injecting a radioisotope into a vein. The isotope flows through the blood vessels of the kidney and is filtered by the glomerulus and/or secreted by the renal tubules. As the isotope flows into the collecting system, it is detected by a nuclear medicine camera usually placed posterior to the kidneys. Radioisotopes can differentiate between passive dilatation and obstruction. T1/2 is the time taken for half of the radiotracer to leave the collecting system which is considered as normal if it is less than 10min, equivocal if it is 10-20min and obstructed if it is >20min. Diuretic renography is the only imaging modality that differentiate UPJO and UVR.
- #26 NSAIDs are superior than opioids in managing renal colic because of a less risk of emesis and less likely to be abused. Mechanism of action is through reduction of renal perfusion and inhibiting PGE mediated down regulation of aquaporins and sodium channels (therefore decreasing tubular hydrostatic pressure) PCN can be done under local anesthesia and ultrasound guidance Opiods – nausea, vomiting ,sedation addiction NSAIDS – better than Opiods – decrease pressure and RBF – decrease collecting system dilation and anti inflammatory, C/I not used in renal Impairement, MI , stroke, Coagulopathy For patients with upper urinary tract obstruction, NSAIDS should be administered with caution .For patients with renal insufficiency or patients with bilateral obstruction, selection of narcotic-based analgesics may be preferred. See ( Campbell 11 th ed p 1101) Drainage – relive pain and improve function by preventing functional decline – endo urologic vs interventional radiologic , Temporary vs Permanenet
- #27 Clinical Scenarios warranting drainage procedures Nephrostomy tube – Urinary diversion, renal allograft, significant anatomic variation How long after drainage we wait -- minimum of 2 – 3 weeks – resolution of infection and obstruction induced inflamations See Comparision b/n stenting vs tube ( emergency urology , p. 113) Recommendation Normal Urinary tract – cystoscopic reterograde ureteral cathterization (before PC nephrostomy tube – if turbid urine – place external ureteral catheter ( see Emergency Uro p.112) – improved – internal stent by double J stent For female pregnant mother urgent decompression - retrograde stenting – stent changing every 4 – 6 weeks b/c of encrustation due to hypercalciuria and hyperuricosuria as same also for tube)
- #28 Post obstructive diuresis is defined as a period of significant polyuria that occurs after relieving obstruction. Majority do not demonstrate post obstructive diuresis. It can be pysiologic in response to retained solutes and water or pathologic due to loss of tubular function like down regulation of sodium channels or aquaporins, poor response of the tubules to vasopressin or altered regulation of ANP. In cases of physiologic post obstructive diuresis majority of the cases resolve as the excess free water and solutes are removed.
- #30 - Read Some points on books. Retrocaval Ureter
- #31 Clinically Important – intra op seems normal grossly – rather than dilation UPJO – Mainly causes are Congenital – faulty programe on Ureteric bud – led to formation of aperistalitic of fibrosed segment , kinked or valved ureter or reduction or Agenesis of fibers extrinsic factors are contributor like Aberrant Vessels anterior to the ureter.
- #32 - Histopathologic studies reveal that the spiral musculature normally present has been replaced by abnormal longitudinal muscle bundles or fibrous tissue. This results in failure to develop a normal peristaltic wave for propagation of urine from the renal pelvis to the ureter . Some studies also shown that interstitial cells of cajal are deficient at UPJ of affected individuals. Production of certain cytokines is also found to exacerbate UPJ obstruction (TGF-B, NO, EGF and neuropeptide Y). Congenital stricture is less common cause of UPJ obstruction and characterized by the excessive deposition of collagen. In case of ureteral folds or kinks the obstruction is normally at the proximal ureter which results from either exaggeration or retention of congenital folds. Though controversy still exists on the effect of crossing vessels, they are present in around 63% of patients with UPJO compared to 20% of cases in normal kidney. C/F OF UPJO :- Asymptomatic, Flank mass, Abdominal pain, Nausea and vomiting, Hematuria, Hypertension (rare) - Asymptomatic hydronephrosis can be diagnosed during routine antenatal ultrasonography or U/S performed for other purpose
- #33 Micro hematuria, UTI, intermitent flank pain,
- #34 Traditionally , such intervention should be a reconstructive procedure aimed at restoring non obstructed urinary flow. Indications for intervention are similar regardless of option of intervention.
- #35 - “Rule of 1/3”
- #36 In more recent days minimally invasive interventions are getting more acceptance than open pyeloplasty with ten fold increment in the past few decades and open interventions decreased by 40% and endo pyeloplasties remain stable. Endo pyeloplasty have high failure rate whereas open and minimally invasive interventions have similar success rate. Nephrectomy is indicated in a patient with poorly functioning or non functioning kidney, patient with repeated failed intervention with normally functioning contra lateral kidney
- #37 It is ideal to perform pyeloplasty without an indwelling ureteral stent or percutaneous nephrostomy in place. The former induces thickening of the ureteral and pelvic walls that complicates suturing; the latter can complicate mobilization of the kidney and lead to bacterial colonization/infection of the renal pelvis. allows the greatest flexibility for more complex cases, such as those with extremely large or mal rotated renal pelvis. The dismembered pyeloplasty - the most widely used repair because of its simplicity and efficacy, but it does have greater potential for postoperative obstruction because of scar contracture of the circular anastomosis
- #38 Anterior extraperitoneal approach :- allows repair with minimal mobilization of the ureter and pelvis. Posterior lumbotomy :- provides direct exposure of the UPJ and also requires minimal mobilization. Both of these incisions are suitable only for thin patients. The flank incision :- is the most familiar approach for most urologist and can be done regardless of the patients body habitus. The flank incision is made from the tip of 12th rib anteriorly to no further than the lateral edge of the rectus muscle. In infants and small children, 3–4 cm should suffice. The incision should follow the skin lines to minimize the scar. Unlike a nephrectomy, there is no need to mobilize the entire kidney unless the UPJ obstruction is secondary to a long segment of narrowed ureter. Through the flank incision, Gerota fascia should be opened vertically as far posteriorly as possible to avoid inadvertently entering the peritoneum. Foley Uretheral catheter is must – bladder drainage for prevention anastomosis leakage
- #39 - Dissection should involve as short a length of the ureter as possible with preservation of the adventitial vessels to prevent devascularization that could result in postoperative stenosis. - For secondary procedures, it may be easier to find normal ureter distally and then dissect proximally toward the scarred UPJ. Crossing lower pole vessels are a more common cause of UPJ obstruction in older children.
- #40 The apex of this lateral, spatulated aspect of the ureter is then brought to the inferior border of the pelvis while the medial side of the ureter is brought to the superior edge of the pelvis. Anastomosis is then performed with fine interrupted or running absorbable sutures placed full thickness through the ureteral and renal pelvis walls in a watertight fashion. Anastomosis is performed over ureteral stent and In general , keep the stent 4 to 6 weeks.
- #41 - Outcome of AH Pyeloplasty - Has 95% success in resolution of clinical symptoms ,and The success rate in decompressing of pelvi- calyceal system on urography is 91%
- #42 Is performed when the renal pelvis is exceptionally redundant Excise redundant portion of the pelvis Close the cephalad portion of the renal pelvis down to the dependent part. Anastomose the dependent portion with the ureter
- #43 PUJ transposition is done when there is aberrant vessel in association with PUJ obstruction.
- #44 - best used in cases with a high insertion of the ureter, particularly in the absence of a dysplastic upper ureter/UPJ segment.
- #46 The base of the flap is positioned anatomically lateral to the UPJ, between the ureteral insertion and the renal parenchyma. Medial line of incision is extended down completely through the obstructed proximal ureteral segment into normal-caliber ureter. The site of the apex for the flap is determined by the length of flap required to bridge the obstruction. The longer the segment of proximal ureteral obstruction, the farther away is the apex because this will make the flap longer. However, to preserve vascular integrity to the flap, the ratio of flap length-to-width should not exceed 3:1
- #47 Has less clinical application. A vertical flap technique may be used when a dependent ureteropelvic junction(UPJ) is situated at the medial margin of a large, box shaped extrarenal pelvis. In contrast to the spiral flap, the base of the the vertical flap is situated more horizontally on the dependent aspect of the renal pelvis, between the UPJ and the renal parenchyma. The flap itself is formed by two straight incisions converging from the base vertically up to the apex on either the anterior or the posterior aspect of the renal pelvis. As for the spiral flap, the position of the apex determines the length of the flap, which should be a function of the length of proximal ureter to be bridged. The medial incision of the flap is carried down the proximal ureter completely through the strictured area into normal-caliber ureter. B, The apex of the flap is rotated down to the most inferior aspect of the ureterotomy. C, The flap is then closed by approximating the edges with interrupted or running fine absorbable sutures.
- #49 The basic concept of the endopyelotomy is a full-thickness lateral incision through the obstructing proximal ureter , from The ureteral lumen out to the peripelvic and periureteral fat. Less effective than Open, Laparoscopic or Robotic and limitations for size of hydronephrosis, Ipsilateral Renal Function , Crossing vessels and concomitant calculi but open suit for all anatomy Contra indication for all Endo pyelotomy :- >2 cm segment , Active Infection or Coagulopathy Complication : - Bleeding needing transfusion, Urine leak , Drainage related hydro pneumothoracic Mid posterior or Superio lateral Calyx are prefered ones
- #50 - ischemia,surgical and nonsurgical trauma,periureteral fibrosis, malignancy ,stones and congenital factor, include radiation; abdominal aortic aneurysm; infections such as tuberculosis and schistosomiasis; endometriosis; and trauma including iatrogenic injury from previous abdominal or pelvic surgery or post–renal ablation injury Roberts et al. (1998) evaluated 21 patients with impacted ureteral stones and found that impaction for more than 2 months’ duration was associated with a 24% incidence of stricture formation. Infectious causes are tuberculosis, schistosomiasis. -
- #51 It is important to assess the renal unit for function before starting treatment because endourologic therapies, in general, require 25% function of the ipsilateral moiety to have reasonable success rates. CT Scan is important to diagnose the presence of obstruction, but antegrade or retrograde pyelography are important to determine the exact site of obstruction.
- #52 Retrograde stenting – intrisnsic causes , balloon dilation + internal stenting for Extrinsic C/I to Balloon dilation – Active infection or > 2 cm segment of stricture
- #53 Endoscopic stent is an option for a patient who is not a candidate for surgical intervention or has poor prognosis. But chronic stenting usually require close follow up because of a risk of eventual compression and needs Percutaneous intervention. Ureteral stenting is not suitable for extrinsic compressions because it could be short lived and needs Percutaneous drainage or surgical intervention.
- #54 This technique involves fluoroscopic assisted visualization of the strictured segment. Traversing the strictured segment with a guide wire, then pass high pressure balloon over it. Balloon inflation at the site of stricture. In antegrade approach balloon dilation is performed using Percutaneous nephrostomy tube. The success rate of balloon dilation depends on the cause of the stricture with 85% success rate for post instrumentation strictures and 50% success rate for post anastomotic stricture. Success rate depends on the cause of the stricture.
- #55 The uretrotomy incision is usually made using cold knife, cutting electrode or holmium laser. Proximally and distally, the endoureterotomy should encompass 2 to 3 mm of normal ureteral tissue. Sometimes balloon dilation after ureterotomy may be required to increase the size of the incision. In general, radiographic follow-up using diuretic renography is recommended for up to 2 years to detect most late failures. It can also be done under fluoroscopic guidance using the hot-wire cutting balloon catheter The success ranges from 66% to 83% - In general,lower ureteral strictures are incised in an anteromedial direction, taking care to stay away from the iliac vessels . In contrast, upper ureteral strictures are incised laterally or posterolaterally ,again away from the great vessels.
- #57 Careful initial evaluation for the nature, location and length of stricture is required. Options are based on Location and length of the Stricture.
- #58 The ureter is a surgically forgiving structure with good vascular supply” (Turner-Warwick). Despite this, meticulous surgical dissection and careful technique are required. A spatulated repair can be used in strictures of up to 3 to 4 cm in length because of the ability to mobilize the ureter. Resect the damaged area and spatulate the two ends for 5-6 mm into good ureter. Perform a tension-free, watertight anastomosis using 4-0 and 5-0 polyglycolic acid suture. Do not place suture knots at the apex; rather, put them at the lateral suture margin, starting the running suture line in the middle of the wall and not at the apex The success rate for a tension-free, watertight ureteroureterostomy is high, more than 90%. A surgical drain is placed, and a Foley catheter is generally left indwelling for 1 to 2 days. The surgical drain may be removed if there is minimal output for 24 to 48 hours - Flank inscion for Upper Ureteral stricture ; Gison or Lower midline inscion for lower uretral stricture and Rocky stick incision for Pfannestine scar
- #59 As is the case in all ureteral repairs, a tension-free anastomosis is critical and thus modifications such as a psoas hitch or Boari flap may be necessary . Repair of the distal ureter can be accomplished by either open or minimally invasive techniques.
- #60 There is no absolute contraindication but small bladder with a limited mobility is considered as relative contraindication. Bladder outlet obstruction or neurogenic dysfunction, if present, must be treated preoperatively . The ureter is transected at the proximal limit of disease, and a stay suture is placed in it. If necessary, a ureteral biopsy may be performed. The distal ureteral stump is ligated with an absorbable suture
- #61 Bladder mobility can be improved by releasing peritoneal attachments and the contra-lateral perivesical attachments. Via the cystotomy, two fingers are placed into the bladder dome, and it is elevated above the iliac vessels and onto the psoas muscle. A tunneled nonrefluxing ureteral anastomosis is preferred but not mandatory. The ureter can be stented with either an internal ureteral stent or an externalized tube. Typically, a urethral catheter is all that is necessary for bladder drainage. If there is concern for hematuria or if bladder closure is tenuous, then a suprapubic tube may be placed. A watertight bladder closure is performed in two layers (mucosal and seromuscular) with absorbable suture. A drain may be left for postoperative monitoring.
- #64 Before the flap is created, the bladder should be distended with saline and the flap carefully planned with a sterile marker.A rectangular flap is created on the anterior surface of the bladder. The most critical maneuver is to preserve blood supply to the flap. Hence the base must be at least 4 cm wide (wider for longer flaps), and the superior vesical artery must be preserved. The flap is sutured to the psoas tendon with non -absorbable sutures. The ureter is tunneled through the proximal portion of the flap and a neo-orifice is created. The bladder flap is tubularized with running absorbable sutures. The distal ureter is anastomosed to the flap using a running absorbable suture. The anastomosis is stented. The anastomotic site is drained. An indwelling urethral catheter drains the bladder
- #65 In such cases the renal vessels—especially the renal vein—limit the extent to which the kidney can be mobilized.
- #66 Reflux to the recipient ureter , if present, must be identified and corrected simultaneously. Therefore a voiding cystogram should be performed preoperatively , in addition to the other imaging and endoscopic studies previously described for thorough evaluation of both ureters. Transureterouretrostomy is rarely used currently. where the injured ureter crosses the midline to meet the contralateral ureter. The recipient ureter should never be angulated to reach the donor ureter. ?? Typically, the anastomosis is unstented.?
- #67 Ileal ureteral subtitution is a complex method of reconstruction which is only used when the other methods are not possible and bladder is not suitable to use it for reconstruction. Normally reconstruction of the urinary stream with urothelial lined epithelium is recommended because it is non absorptive and resistant to inflammatory and carcinogenic effect of urine. In ileal ureteral substitution reflex and increment of only seen during voiding if the reconstruction is isoperistalitic. Only 12% of patients with normal preoperative renal function developed significant metabolic problems postoperatively , and preoperative renal function was identified to be an important prognostic factor .
- #68 It was initially called almond’s disease. The true incidence of the disease is unknown but said to affect 1 per 200, 000 to 5000,000 population. In general, the retroperitoneal fibrotic mass centers around the distal aorta at L4 to L5 and wraps around the ureters, leading to hydronephrosis via extrinsic compression on the ureters or interference with ureteral peristalsis. Most of the time RPF occurs as isolated disease but it can occur as a part of multifocal fibrosis which is a syndrome characterized by sclerosing mediatinitis, sclerosing cholangitis, orbitsl pseudotumor and reidel’s thyroiditis.
- #69 The pain is typically dull aching, non colicky, pain that radiates to the lower abdomen and doesn’t change with position change. The pain also typically improve with aspirin than opoids. Hypertension Oliguria or anuria. Other symptoms are: weight loss, anorexia, nausea, generalized malaise, & fever. Lower leg DVT can occur because of compression of inferior vena cava. The mass can extend to the renal hilum and can cause renal vein hypertension and hematuria. Common finding on CT scan is hydronephrosis with retroperitoneal soft tissue mass enveloping the great vessels. CT urography findings are hydronephrosis with medial deviation of proximal and mid ureter and tapering ureter at the obstruction site. The obstruction is usually bilateral but it could be unilateral.
- #72 - Do not afraid to ask help consult