Management of Upper Urinary Tract Obstruction

1. Management of Upper Urinary Tract Obstruction Jan 2016

2. Obstructive Uropathy • Obstruction can either be defined: • Condition that hampers optimal renal development, or, more conservatively, as a restriction to urinary outflow that, when left untreated, will cause progressive renal deterioration • Currently, management is mostly based on latter definition, but still remains controversial • Conditions may be acute or chronic, complete or incomplete & unilateral or bilateral Csaicsich D, et al. CurrOpinUrol. 2004; 14: 213–217./ O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

4. Classification of Obstructive Uropathy Upper tract Lower tract Acute Chronic Non-function Interactive Unequivocal Equivocal O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

5. Upper urinary tract obstruction: Acute • Intraluminal • Calculi • Sloughed renal papillae • Blood clot • Extraluminal • Acute retroperitoneal pathology • Accidental ureteric ligation Linton KD, et al. Surgery. 2008; 26(5): 197-202.

6. Upper urinary tract obstruction: Chronic • Renal • Congenital obstruction at the pelvi-ureteric junction (PUJ) • Aberrant vessel at the PUJ • Renal cell carcinoma • Transitional cell carcinoma in the renal pelvis • Tuberculosis • Calculi Linton KD, et al. Surgery. 2008; 26(5): 197-202.

7. Upper urinary tract obstruction: Chronic • Ureteric (Intraluminal): • Calculi • Stricture • Ureteric valves • Tuberculosis • Transitional cell carcinoma in the ureter • Ureteritiscystica Linton KD, et al. Surgery. 2008; 26(5): 197-202.

8. Upper urinary tract obstruction: Chronic • Ureteric (Extraluminal): • Ureterocoele • Retrocaval ureter • Aortic aneurysm • Radiation • Retroperitoneal fibrosis • Pregnancy (90% by 3rd trimester) • Para-aortic lymph nodes • Iatrogenic • Intra-abdominal malignancy Linton KD, et al. Surgery. 2008; 26(5): 197-202.

11. Causes of equivocal upper tract obstruction • Ureteropelvic junction obstruction • Primary megaureter • Vesicoureteric junction pathology • Urinary diversions • Previous surgery • Ureterolithotomr • Reimplantation • Pyeloplasty O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

12. Causes of equivocal upper tract obstruction • Previous endourology • Ureteroscopy • Dormia basketry • Retrograde lithotripsy • Apparent ureteric strictures • Pregnancy • Infective dilatation • duplications O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

13. Causes of unequivocal chronic obstruction • Primary megaureter • Retrocaval ureter • Retroperitoneal fibrosis • Urothelial tumors • Ureteric stones • Ureteric strictures • Congenital • Tuberculous • Bilharzial • Iatrogenic • Radiation O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

14. Causes of unequivocal chronic obstruction • Retroiliac ureter • Ovarain vein syndrome • Endometriosis • Extrinsic obstruction • Bowel malignancy (eg. colon) • Pelvic malignancy (eg. ovary, cervix) • Pregnancy • Ureterocele • Bladder cancer O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

15. Causes of unequivocal chronic obstruction Malacoplakia BPH Prostate cancer Procidentia Pelvic lipomatosis Urethral stricture Phimosis O’Reilly PH. Q J Nucl Med. 2002; 46(4): 295-303.

18. Pathophysiology Obstructive Uropathy Obstructive Nephropathy

19. Diagnosis Urinalysis & serum electrolytes, BUN, and creatinine Bladder catheterization, sometimes followed by cystourethroscopy and voiding cystourethrographyfor suspected urethral obstruction Imaging for suspected ureteral or more proximal obstruction or for hydronephrosiswithout apparent obstruction Obstructive UropathyGenitourinary Disorders Merck Manuals Professional Edition.

20. Evaluation of ureteral or more proximal obstruction Abdominal ultrasonography CT Duplex Doppler ultrasonography Excretory urography Antegrade or retrograde pyelography Radionuclide scans MRI Obstructive UropathyGenitourinary Disorders Merck Manuals Professional Edition.

21. Evaluation of hydronephrosis without apparent obstruction Testing may be necessary to determine whether back or flank pain is caused by obstruction in patients who have hydronephrosis but no obvious obstruction revealed by other imaging tests Testing may also be done to detect otherwise unrecognized obstruction in patients with incidentally recognized hydronephrosis Diuretic renography Obstructive UropathyGenitourinary Disorders Merck Manuals Professional Edition.

22. Normal kidney

23. Management of upper urinary tract obstruction Depends upon cause, whether obstruction is unilateral or bilateral & presence or absence of sepsis and/or renal impairment Linton KD, et al. Surgery. 2008; 26(5): 197-202.

24. Medical Management Consultation with urologist should be obtained in patients with urinary tract obstruction, as in hydronephrosis or urinary retention A patient with complete urinary tract obstruction; any type of obstruction in solitary kidney; obstruction with fever or infection; or renal failure needs immediate attention by urologist Patients with pain that is uncontrolled with oral medications or with persistent nausea & vomiting that causes dehydration also need immediate urological attention Kim ED, et al. Medscape. 2014.

25. Medical Management: Partial urinary tract obstruction Partial urinary tract obstruction in absence of infection can be initially managed with analgesics & prophylactic antibiotics until complete urologic evaluation is performed & definitive management is completed Kim ED, et al. Medscape. 2014.

26. Medical Management • Antibiotics are often given for prophylaxis & should cover common urinary tract pathogens • Commonly used antibiotics: • Trimethoprim-sulfamethoxazole, nitrofurantoin, cephalosporins & fluoroquinolones • Pain secondary to urinary tract obstruction is often managed with: • Oxycodone, hydrocodone, acetaminophen & NSAIDs Kim ED, et al. Medscape. 2014.

27. Surgical Management • Surgical intervention is usually obtained once point of obstruction is identified with radiographic imaging • Upper urinary tract obstruction (ureter, kidney) can be relieved with following: • Ureteral stent • Nephrostomy tube Kim ED, et al. Medscape. 2014.

28. Ureteral stent Flexible tube that extends from renal pelvis to bladder It can be placed during cystoscopy to relieve obstruction along any point in ureter Generally needs to be changed every 3 months Kim ED, et al. Medscape. 2014.

29. Ureteral stent Kim ED, et al. Medscape. 2014.

30. Nephrostomy tube Flexible tube that is placed through back directly into renal pelvis If a ureteral stent cannot be placed cystoscopically in retrograde fashion, a percutaneous nephrostomy tube can be inserted for relief of hydronephrosis If needed, a ureteral stent can then be passed in an antegrade fashion through nephrostomy tube tract Kim ED, et al. Medscape. 2014.

31. Ultrasonic probe for guidance the nephrostomy tube placement Lojanapiwat B. Modern Surgical Treatments of Urinary Tract Obstruction.

32. Dilators over the guidewire Lojanapiwat B. Modern Surgical Treatments of Urinary Tract Obstruction.

33. 8 Fr nephostomy catheter inserted through the guidewire Lojanapiwat B. Modern Surgical Treatments of Urinary Tract Obstruction.

34. Nephrostomy tube is secured with skin Lojanapiwat B. Modern Surgical Treatments of Urinary Tract Obstruction.

35. Preoperative details Before any surgical intervention or any manipulation of urinary tract, broad-spectrum antibiotics should be initiated to prevent infection or urosepsis Ideally, before any manipulation is performed, urine should be sterile. However, this may not be possible in cases of emergent surgical intervention Urine culture along with the administration of broad-spectrum antibiotics is important If cystoscopy & stent are needed emergently, coagulation is not a concern. If percutaneous drainage is necessary, coagulopathies should be corrected Kim ED, et al. Medscape. 2014.

36. Intraoperative details Different interventions can be performed to temporarily relieve point of obstruction If planned procedure cannot be performed safely or is not adequate in relieving urinary tract obstruction, other modes of urinary tract decompression can be tried Kim ED, et al. Medscape. 2014.

37. Postoperative details When a patient has long-standing urinary tract obstruction that has been relieved, they may experience postobstructivediuresis This physiologic diuresis is usually self-limiting & can be managed conservatively with fluid replacement and, if needed, electrolyte replacement Postobstructive diuresis defined: Diuresis of more than 200 mL/h for at least 2 hrs Kim ED, et al. Medscape. 2014.

38. Postoperative details Patients with severe diuresis should receive intravenous fluid replacement in form of half normal saline at 80% of hourly urine volume for 1st 24 hrs, then 50% Postobstructivediuresis usually lasts 24-72 hrs Most cases are not severe enough to require this level of attention Kim ED, et al. Medscape. 2014.

39. Follow up Definitive treatment at point of obstruction is needed after acute obstruction is resolved Adults and children often have different etiologies of urinary tract obstruction. Thus, various definitive surgical treatment options are available for each condition After definitive treatment is achieved, final imaging study is obtained to verify complete relief of obstruction Type of study performed, as well as timing of study, is left to discretion of urologist Kim ED, et al. Medscape. 2014.

40. Complications • A patient with urinary tract obstruction should see urologist promptly because of serious complications that obstruction can impose. Following are complications of obstructive uropathy: • Infection, including cystitis (bladder infection), pyelonephritis (kidney infection), abscess formation & urosepsis • Urinary extravasation with urinoma formation • Urinary fistula formation • Renal insufficiency or failure • Bladder dysfunction secondary to a defunctionalized bladder • Pain Kim ED, et al. Medscape. 2014.

41. Outcome and prognosis Prognosis of urinary tract obstruction depends on cause, location, degree & duration of obstruction, as well as presence of UTI Longer the duration of obstruction, greater the severity of obstruction & presence of concomitant infection can lead to worse prognosis Prognosis is favorable if renal function is normal, infection is cleared & obstruction is relieved in timely manner Kim ED, et al. Medscape. 2014.

42. Acute treatment of upper urinary tract obstruction To re-establish urinary drainage Timing (immediate vs. delayed), approach (endoscopic, percutaneous, open, laparoscopic) & goals of treatment (temporizing vs. definitive) depend heavily on diagnostic workup When safe & possible, an effort should be made to provide definitive treatment at the same time as urinary drainage is established Hohenfeller M, et al. Emergencies in Urology. 2007. 10.4 Acute Urological Management. Pg 111.

43. Acute treatment of upper urinary tract obstruction In cases of renal failure, concurrent infection or complete obstruction, however, only goal of treatment should be urgent decompression of blocked upper tract Hohenfeller M, et al. Emergencies in Urology. 2007. 10.4 Acute Urological Management. Pg 111.

44. Acute decompression Presence of sepsis & upper tract obstruction: Urological emergency Pyonephrosismay be present (Greek pyon- pus, nephros - kidney). In this instance, treatment options are percutaneous nephrostomy or JJ ureteric stent insertion Nephrostograms are useful to show level & aetiology of obstruction, but should not be performed until sepsis has been adequately treated. Decompression usually allows ureteric peristalsis to resume & sometimes spontaneous stone passage occurs Linton KD, et al. Surgery. 2008; 26(5): 197-202.

45. Nephrostogram following nephrostomy tube placement due to azotemia& pyonephrosisdemonstrated impacted upper ureteric calculi Lojanapiwat B. Modern Surgical Treatments of Urinary Tract Obstruction.

46. Acute decompression Decompression is also indicated in renal failure, particularly in presence of hyperkalaemia & fluid overload Patients with renal failure due to upper tract obstruction or obstruction from malignant cause requiring chemotherapy, can undergo decompression with either nephrostomy tube or JJ stent insertion to optimize their renal function Some patients with renal failure for whom it is more appropriate to undergo initial renal replacement therapy & then subsequent nephrostomy tube placement Linton KD, et al. Surgery. 2008; 26(5): 197-202.

47. Urgent temporary decompression Urgent temporary decompression, when warranted, is performed either with retrograde placement of ureteral stents or percutaneous nephrostomy tube placement Retrograde technique also provides option that drainage be performed with external ureteral catheter or an internal double pigtail stent Both procedures have an established track record with high success rates & low complication rates Hohenfeller M, et al. Emergencies in Urology. 2007. 10.4 Acute Urological Management. Pg 111.

48. Urgent temporary decompression • Following clinical scenarios would typically warrant a temporary drainage procedure (ie., stenting or percutaneous nephrostomy): • Complete ureteral obstruction (unilateral or 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 Hohenfeller M, et al. Emergencies in Urology. 2007. 10.4 Acute Urological Management. Pg 111-2.

49. Urgent temporary decompression Individualized clinical circumstances may also dictate use of temporizing interventions for other patient populations such as uncontrollable flank pain, fever, or uncontrollable gastrointestinal complaints Indeed, when a decision is being made regarding use of temporary drainage procedure vs definitive therapy for initial relief of upper urinary tract obstruction, it is advisable to err on the side of conservative temporizing therapy rather than immediate definitive therapy Not commonly, patients requiring an acute drainage procedure can have significant morbidity & can be acutely ill Hohenfeller M, et al. Emergencies in Urology. 2007. 10.4 Acute Urological Management. Pg 112.

50. Calculi Obstruction due to calculi often presents acutely with pain unilaterally Treatment for calculi depends on their size & location within upper tract Linton KD, et al. Surgery. 2008; 26(5): 197-202.