Renal Injury

DR.AHMED TURKI

Renal injury
Most common injury of the urinary tract is blunt trauma directly to the flank and account 80-85% of the cases. Gun shot and knife wounds cause most penetrating injury, in injury from rapid deceleration, the kidney move up and down cause sudden stretch of the renal pedicle, sometimes complete avulsion of the renal pedicle .
Pathological classification
Grade 1: renal contusion or bruising of the renal parenchyma.
Grade 2 : renal parenchymal laceration into the renal cortex , small perirenal hematoma.
Grade 3: renal parenchymal laceration extend into the renal cortex and medulla with large retroperitoneal hematoma.
Grade 4: renal parenchymal laceration extend into the renal collecting system , segmental vein or main artery thrombosis from blunt trauma.

Grade 5 : multiple grade 4 laceration , renal pedicle avulsion.

Late complication :
Urinoma: deep laceration that are not repaired .
Hydronephrosis: large retroperitoneal hematoma and urinary extravasation result in perinephric fibrosis that engulf the ureteropelvic junction.
Arteriovenous fistula.
Renal vascular hypertension.
Treatment
Emergency treatment : treatment of shock , hemorrhage.
Surgical treatment : minor renal injury from renal trauma account 85%, do not require operation . bleeding stop spontaneously wit bed rest and hydration , surgery indicated when there is persistent retroperitoneal bleeding , urinary extravasation and renal pedicle injury.
Penetrating injury : should surgically explored.
Ureteral injury
Rare but may occur : course of difficult pelvic surgery or gun shot and endoscopic basket manipulation, the ureter may be inadvertently ligated and cut during difficult pelvic surgery. In such cases sepsis and severe renal damage usually occur postoperatively, if the ureter partially divided and not recognized at operation , urinary extravasation occur lead to ureterovaginal and ureterocutaneous fistula.
Symptoms:
Partial or complete ureteric ligation usually marked by fever, flank pain, ureterovaginal or ureterocutaneous fistula usually occur in the 1st 10 days postoperatively .
Signs :
Totally ligated ureter lead to severe flank pain , nausea and vomiting , early in the post-operative course, or sign of peritonitis if urine extravasated in the peritoneal cavity or watery discharge from vagina in ureterovaginal fistula.
Laboratory finding :
microscopic hematuria in 90% of the cases.
Imaging : delay abdominal spiral CT scan with contrast , ultrasonography : outline hydronephrosis, hydroureter or urinary extravasation and urinoma.
Treatment :
If the injury discover during the operation prompt treatment is the best, if the injury diagnose until 7-10 days postoperatively and there is no infection, abscess or other complication , immediate exploration and repair , otherwise if the injury diagnose late so proximal urinary drainage by percutaneous nephrostomy and then delay definitive repair.
Lower 1/3 of the ureter:
Many option , either reimplantation of the ureter, or bladder tube flap can be use when the ureter is shorter.
middle 1/3 of the ureter:
best by primary ureteroureterostomy.
Upper 1/3 of the ureter:
Best manage by primary ureteroureterostomy or transureteroureterostomy .