Pyeloplasty: Surgical Treatment of Ureteropelvic Junction Obstruction
Indications for Pyeloplasty
Pyeloplasty is indicated as surgical therapy for ureteropelvic junction obstruction:
with scintigraphic evidence of obstruction
with decreasing (but sufficient) renal function of the affected kidney
with clinical symptoms (flank pain, nephrolithiasis or recurrent infections)
Contraindications for Pyeloplasty
Nonfunctioning kidney (under 20% of total renal clearance). Coagulation disorders. Comorbidity, which prohibits elective surgery.
Surgical Technique of Pyeloplasty
fig surgical technique of dismembered pyeloplasty
Principles of dismembered pyeloplasty: schematic drawing of a ureteropelvic junction obstruction due to a lower pole-crossing vessel (left). Dismembered pyeloplasty (technique by Anderson and Hynes) with reposition of the ureter in relation to the lower pole-crossing vessel (right).
figure intraoperative findings of a UPJ obstruction caused by a lower pole renal vessel
Intraoperative findings of a UPJ obstruction (1) with lower pole renal vessels (2).
Preoperative Patient Preparation
Exclusion or treatment of a urinary tract infection
Insertion of a DJ ureter stent and insuring the diagnosis with retrograde pyelography
Perioperative antibiotic prophylaxis
Insertion of a transurethral catheter
Surgical Approach via a Flank incision
Flank position of the patient, the operation room table is flexed. The surgical approach to the kidney is done with a flank incision. In children, an anterior subcostal muscle-splitting approach is preferable.
Preparation of the ureter after opening of Gerota's fascia. Dissection of the renal pelvis on the anterior and dorsal side.
Dismembered Pyeloplasty
Dismembered pyeloplasty is the method of choice, if a crossing vessel is identified as cause for the UPJ obstruction, and probably for most other indications. Traction sutures are placed at the renal pelvis. Excision of the UPJ obstruction is done with, if necessary, excision of excess renal pelvis (reduction pyeloplasty). The ureter is spatulated along the lateral wall (2–3 cm) [fig. dismembered pyeloplasty]. The ureter is repositioned in relation to the crossing vessel, resulting in an anastomosis ventral of the crossing vessels.
The anastomosis between the ureter and renal pelvis is done with fine PDS or Vicryl sutures (4-0, in children even finer). First, the cranial part of the opened renal pelvis is closed with a running suture. The caudal part of the renal pelvis (2–3 cm) is left open for the anastomosis with the ureter. The ureter is anastomosed with either a running or interrupted suture to the caudal portion of the renal pelvis. Before the last sutures are done, the position of the ureteral stent is controlled. A drain is placed near the anastomosis.
Care after Pyeloplasty
General measures:
Early mobilization. Respiratory therapy. Thrombosis prophylaxis. Laboratory controls (Hb). Wound inspections.
Analgesia:
In adults, a flank approach is painful and an epidural catheter is an option. In addition, analgesics according to the ladder of WHO pain management are given, e.g. metamizol and tramadol.
Drains and catheters:
Wound drainage 1–2 days
Bladder catheter 3 days
Ureteral stent 2–4 weeks
Complications of Pyeloplasty
Bleeding, infection, urinoma, recurrent ureteral stricture, loss of kidney function, injury to adjacent organs (liver, spleen, pancreas).