URETERAL INJURIES HOUSSAM GALAL OSMAN AUG-2007 GENARAL CONSIDERATION ANATOMY • ureters are the two tubes which convey the urine from the kidneys to the urinary bladder. • Ureter Proper measures from 25 to 30 cm in length. • abdominal part lies behind the peritoneum on the medial part of the Psoas major, and is crossed obliquely by the internal spermatic vessels. It enters the pelvic cavity by crossing either the bifurcation of the common, or the commencement of the external iliac vessels. • right ureter is usually covered At its origin the by the descending part of the duodenum, and in its course downward lies to the right of the inferior vena cava, and is crossed by the right colic and ileocolic vessels, while near the superior rim of the pelvis it passes behind the lower part of the mesentery and the terminal part of the ileum. • left ureter is crossed by the left colic vessels, and near the superior brim of the pelvis passes behind the sigmoid colon and its mesentery. • pelvic part runs at first downward on the lateral wall of the pelvic cavity, along the anterior border of the greater sciatic notch and under cover of the peritoneum. It lies in front of the hypogastric artery medial to the obturator nerve and the obturator and middle hemorrhoidal arteries. It reaches the lateral angle of the bladder, where it is situated in front of the upper end of the seminal vesicle and at a distance of about 5 cm from the opposite ureter,at this site the ductus deferens crosses to its medial side, and the vesical veins surround it. • In the female, the ureter forms the posterior boundary of the ovarian fossa, in which the ovary is situated. It then runs medialy and forward on the lateral aspect of the cervix uteri and upper part of the vagina to reach the fundus of the bladder. In this part of its course it is accompanied for 2.5 cm by the uterine artery, which then crosses in front of the ureter and ascends between the two layers of the broad ligament. The ureter is distant about 2 cm from the side of the cervix of the uterus. • The arteries supplying the ureter are branches from the renal, internal spermatic, hypogastric, and inferior vesical. CAUSES OF URETERAL INJURY 1- penetrating trauma 2- Iatrogenic during abdominal or pelvic surgery; Crushing from misapplication of a clamp. Ligation with a suture. Transection (partial or complete) . Angulation of the ureter with secondary obstruction . Ischemia from ureteral stripping or electrocoagulation. Resection of a segment of ureter. Steps that can differentiate the ureter from a blood vessel with a similar appearance include pinching the structure with forceps and watching for peristalsis. If peristalsis occurs, the ureter has been identified. Additionally, a fine needle can be placed into the lumen of the questionable structure. If urine is retrieved through aspiration, the ureter has been identified; if blood is aspirated, the structure is a blood vessel. CLINAICAL MANIFESTATIONS A- unilateral injury: No symptoms: silent atrophy of the kidney. Loin pain and fever: possibly with pyonepherosis. Urgent steps to relieve the obstruction should be taken. urinary fistula: through the abdominal or vaginal wound. B- bilateral injury: Anuria , urgent relief of obstruction is mandatory. INVESTIGATION Intraoperatively : If the ureteral injury is noted intraoperatively and additional imaging is necessary to localize the lesion, the best imaging study is retrograde ureteropyelography. Postoperatively : laboratory tests, including a CBC with manual differential and an electrolyte panel with BUN and creatinine, are needed to assess for possible infection and renal dysfunction. imaging studies evaluating for hydronephrosis, ipsilateral renal function, and continuity of the ureter are necessary. These imaging studies may include an intravenous urogram (IVU), an abdominal and pelvic CT scan with IV contrast, a renal ultrasound, and/or retrograde ureteropyelography. REPAIR OF INJURED URETER GENERAL CONSIDERATION: If the patient is unsuitable for surgery because of sepsis or hemodynamic instability, urinary diversion in the form of a percutaneous nephrostomy tube placement should be performed. Surgical repair depends on the level of the injury and the length of the injured segment. Important principles for surgical repair include a creation of a tension-free anastomosis, water-tight mucosal approximation, stenting, coverage of the repair with vascularized tissue, and appropriate drainage. Upper ureter (upper ureter or the UPJ): primary anastomosis of the renal pelvis and the ureter. Middle ureter. (abdominal ureter): Ureteroureterostomy. Large defects in the abdominal ureter may necessitate transureteroureterostomy. Distal ureter (pelvic ureter): reimplantation into the bladder. Larger defects can be bridged by performing a vesicopsoas hitch, in which the bladder is sewn to the central tendon of the psoas muscle. Complex bladder or vascular injuries in the pelvis make transureteroureterostomy a more attractive option. POSTOPERATIVE CARE Closed-suction retroperitoneal drainage and Foley catheter decompression of the bladder are essential. Retroperitoneal drains may have significant output for several days but are removed after 2 to 3 days unless output is consistent with a urine leak. Bladder catheterization is necessary for 7 days after ureteral reimplantation.
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