Kidneys and ureters small animal surgery.pptx

Kidneys and ureters small animal surgery.Dr.Aman Ullah Zubair
[DVM][RVMP]
Small animal surgery
Surgical Procedures:
Nephrolithotomy: (removal of calculi through nephrotomy)
Pyelolithotomy: (removal of calculi through proximal ureter & pelvis)
Total Nephrectomy
Partial Nephrectomy
Ureterotomy
Ureteral Anastomosis
Ureteroneocystostomy (For Ectopic Ureters)

1. URINARY SYSTE.AM Kidneys Ureters Dr.Aman Ullah Zubair [DVM][RVMP]

2. LECTURE CONTENTS Surgical Procedures: Nephrolithotomy : (removal of calculi through nephrotomy ) Pyelolithotomy: ( removal of calculi through proximal ureter & pelvis) Total Nephrectomy Partial Nephrectomy Ureterotomy Ureteral Anastomosis Ureteroneocystostomy (For Ectopic Ureters)

3. URINARY SYSTEM (1) A. Kidneys: Lie in the retroperitonial space, lateral to aorta and CdVC . Have fibrous capsule & are held in position by subperitoneal C.T. Pelvis is funnel-shaped; receives urine and directs it into the ureter. Renal artery arises from dorsal aorta, normally bifurcates into dorsal and ventral branches; however, variations are common. B. Ureters : Fibromuscular tubes, begin at renal pelvis, prox portion retroperitoneal, distal portion peritoneal; enter the dorsal surface of bladder obliquely in the trigone area.

4. Urinary System (2) C. Urinary Bladder: Position varies with the amount of urine it contains Main parts ( Fundus , body, neck & trigone area) B.S from cranial & caudal vesicular arteries Sympathetic innervation from hypogastric nerves Somatic innervation to external bladder sphincter & striated muscles of urethra from pudendal nerve D. Urethra: From neck of bladder to the exterior Somatic innervation from pudendal nerve Divided into prostatic and penile portions

5. 1. Nephrolithotomy (removal of calculi through nephrotomy )-1 Indications: Renal calculi lodged in renal pelvis (most common) Surgical Tech: Midline laparotomy from xiphoid to caudal to umbilicus Grasp peritoneum over caudal pole of kidney with tissue forceps and incise with scissors Insert your finger into this opening & gently peel off the peritoneum Reflect perirenal fat from ventro -medial surface of the hilus to expose renal vein and ureter Lift the kidney from its bed, retract medially, reflect the perirenal fat from dorsolateral surface to expose the renal artery Temporarily ligate the renal artery with a vascular forceps or Rumel tourniquet.

6. Nephrolithotomy ( 2 ) Cut through renal parenchyma from cranial to caudal pole up to the pelvis with a single incision without bisecting the kidney Remove calculi Close the incision with three equally spaced horizontal mattress sutures through deep region of the renal cortex using 2/0 PGA. Use straight needle . Close capsule of the kidney with continuous suture line using 3/0 PGA. The sutures in the renal cortex and capsule should not be tight Remove the vascular forceps or the tourniquet, check for bleeding, return kidney to N place and perform nephropexy Organ ischemia should not exceed 30 minutes

7. Mobilizing the kidney

8. Exposure of renal artery, vein & ureter

9. Exposure of renal artery, vein & ureter

10. Internal Structure of Kidney

11. Nephrotomy closure

12. Pyelolithotomy (removal of calculi through proximal ureter & pelvis)-1 May be used to remove the calculus if the prox ureter and renal pelvis are sufficiently dilated. Avoids trauma to renal parenchyma; however, it is extremely difficult if the ureter is not dilated. Surgical Tech: Mobilize the kidney Make incision over the dilated pelvis & proximal ureter and remove the calculi. Flush the renal pelvis and diverticula with warm saline solution to remove any debris Pass 3.5-French soft rubber catheter through ureter from kidney to the bladder to ensure the patency of the ureter In case of ureteral or cystic calculi, perform ventral cystotomy and deal with the situation Close the incision in a continuous pattern using 4/0 or 5/0 absorbable suture.

13. Successive steps in pyelolithotomy

14. Total Nephrectomy (1) Indications: Renal neoplasia / solitary renal cysts Severe trauma (uncontrollable hemorrhage / urine leakage) Pyelonephritis refractory to medical treatment Hydronephrosis Irreparable ureteral abnormalities Dioctophyma renale with severe degenerative changes Note: Always assess the function of other kidney before elective unilateral nephrectomy (Renal Scintigraphy / Scan): Structural & functional evaluation of the kidney.

15. Renal Tumor

16. Total Nephrectomy ( 2 ) Surgical Tech: Midline laparotomy; Expose the kidney Peel off the peritoneum, mobilize the kidney and expose the artery, vein and ureter as described for nephrotomy Ligate the artery and the vein (Don’t ligate them together) Be careful in case of left kidney, as the left ovarian and testicular veins drain into the renal vein Ligate the ureter near the bladder Remove the kidney and ureter Close laparotomy incision

17. Partial Nephrectomy (1) Seldom performed in dogs and cats Cranial or caudal pole trauma, benign tumors Expose the kidney Vascular clamp or Rumel tourniquet Strip back capsule from the area to be resected Apply 3 tight horizontal mattress sutures distal to the portion to be resected Resect the diseased or damaged tissue Control hemorrhage Close capsule over the tissue; however, capsule is often too flimsy to hold sutures Site may be covered with omentum Perform nephropexy and close the laparotomy incision

18. Partial Nephrectomy

19. Ureteral Obstruction / Damage (1) Etiology: Intraluminal & extraluminal causes Urolithiasis , congenital / acquired strictures, neoplasia , inflammatory disease, fibrosis, blood clots Clinical Signs: Postrenal azotemia (bilateral obstruction) Clinical signs of uremia generally not present in cases of unilateral obstruction if contralateral kidney is functional and remains unobstructed Hydronephrosis , pyelonephritis, septicemia and possible death in cases of urinary outflow obstruction with UTI Progressive dilation of urinary tract proximal to obstruction results in hydronephrosis , damage to renal parenchyma and loss of renal function. Treatment: Ureterotomy, ureteronephrectomy (in extreme or irreparable damage

20. Ureteral Obstruction / Damage (2) Ureterotomy: Occasionally performed to remove obstructed calculi. Surgical Tech: Make a longitudinal or transverse incision in the dilated ureter prox to the calculi & remove them. Place a small, soft rubber catheter into the ureter prox & distal to the incision and flush with warm fluid Make sure patency of the ureter Close the incision in S.I. fashion with 5/0 to 7/0 absorbable suture. Incision may be closed in a transverse fashion

21. Closure of ureterotomy incision

22. Ureteral Obstruction / Damage (3) Ureteral Anastomosis: Recommended if the ureter is badly damaged Technically difficult in small patients Perform ureteroneocystostomy if damage is near the bladder Perform nephrectomy if irreparable damage is in the proximal ureter (other kidney normal) Surgical Tech: Suture the ureteral ends directly or spatulate them making longitudinal incisions on opposite sides Preplace sutures at the apex of the spatulated incisions, align the ureteral ends & tie the sutures. Close the remainder of the ureter with S.I. sutures. Stenting ?

23. Ureteral Anastomosis

24. Ectopic Ureters (1) congenital condition, usually seen in female dogs [ M:F =1:25 ] May be; Intramural Extramural Double ureteral openings Ureteral troughs

25. Normal opening of ureter in the trigone area

26. Different types of ectopic ureter Intramural Extramural Double Ureteral Openings Ureteral Troughs

27. Ectopic Ureters (2) Clinical Signs: Urinary incontinence (continuous or intermittent), voiding may be normal, chronic vulvar dermatosis Diagnosis: Positive contrast urinary radiography (I/V excretory urogram ); may show opening of the ureter in the urethra, uterus or vagina Ectopic ureters frequently dilate ( Hydroureter , Hydronephrosis ) in response to increased resistance to urine flow at the ureteral exit Many animals may have UTI Renal function is usually normal, but should be confirmed by RFTs .

28. Ectopic Ureters (3) Treatment: Ureteroneocystostomy ( Reimplantation of the ureter into the bladder lumen) This procedure can also be performed in case of damage to ureter near urinary bladder

29. Ectopic Ureters (4) Surgical Tech: Perform ventral cystotomy Ligate the ureter & transect it Place a stay suture on the end of transected ureter Incise the dorsal bladder mucosa & create a short, oblique submucosal tunnel in the bladder wall and exit through the mucosal, muscular and serosal layers. Use the stay suture to draw the ureter into bladder lumen Spatulate the end of the ureter & suture it to the mucosa

30. Ureteroneocystostomy