Renal injuries can occur from either blunt or penetrating abdominal trauma. Blunt injuries are more common and cause 90% of renal injuries. Injuries are classified from Grade I to Grade V based on severity. Minor injuries (Grades I-II) can often be managed non-operatively with monitoring but major injuries (Grades III-V) may require surgery, especially if there is continued bleeding or other serious injuries. Complications can include bleeding, infection, urinomas, and long term issues like hypertension if not properly treated. Surgery is aimed at repairing or removing injured portions of the kidney while preserving functioning tissue.

1. RENAL INJURY
DR.B.SELVARAJ MS;Mch;FICS;
‘Surgical Educator’
MALAYSIA
ABDOMINAL TRAUMA

2. RENAL INJURY
Epidemiology
Mechanism of injury
Grading/Classification
Initial evaluation
Management
Treatment Algorithm
Complications
LEARNING OBJECTIVES

3. RENAL INJURY
Among all abdominal trauma patients 10% of them get urinary tract
injuries. Renal trauma is 1 to 5% of all traumas
90% of renal injuries are because of blunt injuries and 10% are due
to penetrating injuries
In renal injuries due to blunt trauma other associated injuries like
liver,spleen, bowel injuries are 44%
In renal injuries due to stab wounds or gunshot wounds, other
associated intra abdominal injuries are 40 to 70% and 77 to 100%
respectively
EPIDEMIOLOGY

4. RENAL INJURY
Blunt trauma
Motor vehicle collisions, falls,
and direct blows to the flank
lead to renal injuries as the
kidney is thrust against the rib
cage or vertebral column.
Fractured ribs and transverse
processes of the lumbar spine
can also lacerate the kidney
Mechanism Of Injury
 Penetrating trauma
 1. Stab wounds and gunshot wounds
tend to be less predictable and more
severe than blunt trauma.
 2.Stab wounds to the anterior
abdomen are more likely to injure vital
renal structures such as the pelvis,
hilum, and pedicle. Flank wounds
posterior to the anterior axillary line
are more likely to injure peripheral
and nonvital renal structures such as
parenchyma
 3. Gunshot wounds may cause
extensive tissue disruption due to
 Sudden deceleration injuries
Sudden deceleration may:
 1. Stretch the renal artery and
produce an intimal tear, producing
turbulence,thrombosis, and occlusion
with complete or segmental renal
ischemia.
 2. Avulse the ureteropelvic junction
(UPJ)

5. RENAL INJURY
GRADING
AAST Grading

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Initial Evaluation
 The goal is prompt recognition and
appropriate radiographic evaluation of all
upper urinary tract injuries.
 Major blunt renal injury usually occurs
with other major injuries of the head,
chest, and abdomen.
 A.History
 1. Mechanism of injury—blunt,
penetrating, or deceleration
 2. Type of weapon used
 3. History of hypotension in the field
B. Physical examination
1. Flank pain or ecchymosis
2. Lower rib or vertebral body fractures
3. Upper abdominal mass or tenderness
4. Crepitance over lower rib cage or lumbar area
5. Site of gunshot wound entrance or stab wound
penetration
6. Abdominal distension or ileus (may be associated
with retroperitoneal urinary extravasation)

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Initial Evaluation
C. Laboratory studies
1. Urinalysis
a. Gross hematuria or microscopic hematuria
(defined as >5 red blood cells per high-power
field) associated with hypotension (systolic blood
pressure <90 mm Hg) indicates the need for
genitourinary tract imaging.
b. The degree of hematuria does not correlate
with the severity of renal injury.
2. Hematocrit is helpful in selective operative
versus nonoperative management of renal trauma.
3. Creatinine, if elevated, may suggest preexisting
renal disease, which may change the approach to
radiographic evaluation and operative approach.
D. Radiologic evaluation of renal injury
Indications for genitourinary imaging are as follows:
1. Penetrating injury associated with any degree of
hematuria or if the wound tract indicates possible
genitourinary involvement
2. Blunt trauma associated with:
a. Gross hematuria
b. Microscopic hematuria and associated hypotension or
history of hypotension (blood pressure < 90 systolic)
c. Injuries in proximity to urogenital structures (lower
spine, rib, and transverse process fractures, pelvic
fractures)
3. Significant deceleration injury (e.g., fall from height)
4. All pediatric patients with any degree of hematuria

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Radiology- CECT
Male, 46-year-old, blunt
abdominal trauma. Grade 1- CT:
focal areas of decreased contrast
enhancement in the mid-cortex
of the right kidney (arrows).
Grade I renal injury also includes
non-expanding subcapsular
hematomas without parenchymal
laceration
Male, 47-year old, blunt abdominal
trauma. Subsegmental infarction.
CT: wedge-shaped area of
decreased attenuation in the
interpolar region of the right kidney
(arrow).

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Radiology-CECT
Grade 2: Small cortical
laceration. CT: laceration in
the interpolar region (arrow)
of the right kidney with a
small perinephric hematoma
(arrowhead).
Grade III injuries include renal
lacerations greater than 1 cm,
but without the collecting
system involvement
Male, 32-year-old, road traffic accident.
Major renal laceration through the cortex
extending to the medulla without
involvement of the collecting system. CT:
large sub-capsular hematoma, complete
renal laceration of the right kidney
(arrow).

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Radiology-CECT
Grade IV injuries include
deep parenchymal lacerations
extending through the renal
cortex and medulla into the
collecting system, injuries
involving the main renal
artery or vein with contained
hemorrhage
Male, 12-year-old, fall from a
staircase. Deep parenchymal
laceration involving collecting
system. (A, B) – unenhanced and
post-contrast CT: large sub-capsular
hematoma, intrarenal hematoma and
corticomedullary laceration of the
right kidney with hyperdense
presentation of blood in unenhanced
scans (A) and hypodense in post-
contrast scans (B), (arrows). (C) – CT:
filling defect within the urinary
bladder due to blood clot. (D) –
Urography: filling defect in the right
renal pelvis due to blood clot
(arrow).

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Radiology-CECT
Grade V injuries are the
most severe and include
lacerations that
completely shatter the
kidney, PUJ avulsion
(Figure 9A, 9B), complete
laceration (avulsion) or
thrombosis of the main
renal artery or vein that
devascularizes the kidney
Male, 43-year-old, blunt
abdominal trauma. Avulsion of
the pelvi-ureteric junction.
(A) – CT: extravasated
contrast medium (arrows), (B)
– CT excretory phase:
extravasated urine with
contrast medium (arrow).

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Radiology-Angiogram

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Management
 A. Minor renal injuries (grades 1 and 2)
account for 70% of all injuries and they do not
require intervention.
 B. Major renal injuries (grades 3 and 4)
account for 10% to 15% of all injuries. Their
management depends on the clinical status of
the patient and other associated injuries.
 1. Patients who are hemodynamically stable
with grade 3 or 4 renal injury may be
managed conservatively if celiotomy is not
indicated for treatment of associated injuries.
 2. When celiotomy is indicated for treatment of
associated injuries,renal exploration and
reconstruction are recommended.
 3. Grade 4 injuries involving the main renal artery
require exploration
 4. All penetrating injuries to the kidney are
explored.

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Management
 C. Grade 5 injuries account for 10% to 15% of
all injuries.
 1. Grade 5 injuries involving the renal pedicle
always require immediate surgery to control
life-threatening bleeding and typically result in
nephrectomy.
 2. Renal artery thrombosis 6 hours after injury
warrants a conservative approach as renal
salvage is unlikely after ischemia of this
duration (unless it involves a solitary kidney,
bilateral kidneys, or a pediatric patient).
 3. Conservative management of multiple
parenchymal fractures may be done in select
patients who are hemodynamically stable at
presentation and do not have a renal pedicle
injury.
 4. Urologic complications in cases managed
nonoperatively may often be approached by
minimally invasive endourological techniques
such as retrograde stenting for persistent
urinoma

15. RENAL INJURY
Management
 D. Absolute indications for renal exploration
 1. Persistent, life-threatening bleeding;
expanding, pulsatile, or uncontained
retroperitoneal hematoma
 2. Renal pedicle avulsion
 E. Relative indications for renal exploration
 1. Persistent renal bleeding defined as requiring
transfusion >3 units of packed red blood cells/24
hours
 2. Extracapsular urinary extravasation
 3. Nonviable renal tissue
 4. Incomplete staging- When a renal injury has
not been accurately staged preoperatively, an
intraoperative one-shot intravenous pyelogram
should be performed.
 “Damage control”—as an alternative to
nephrectomy, if the patient is hypothermic,
acidotic, or coagulopathic, initial packing of
renal fossa is followed by definitive repair
after correction of the metabolic
derangements.

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Management
 Nonoperative approach consists of
supportive care with bed rest, serial hematocrit
assessment, volume repletion, antibiotics, and
careful monitoring and imaging follow-up using
repeated CT scans.
 Operative approach to the kidney
 1. Midline transabominal incision
 2. Major visceral and vascular injuries should
be repaired first unless renal hemorrhage is
massive and life threatening.
 3. Early isolation of the renal vessels
 4. Incision of the retroperitoneum over the aorta
medial to the inferior mesenteric vein
 5. Superior dissection will reveal the left renal
vein crossing the aorta anteriorly. Both renal
arteries should be easily seen at this time. All
vessels are encircled with vessel loops
 6. The kidney is now approached by incising the
retroperitoneum lateral to the colon.
 7. For massive bleeding, the ipsilateral renal
artery may be occluded, but warm ischemia time
should be limited to less than 30 minutes.

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Complications
 Early complications (within 30 days) may
include
 Bleeding, infection
 Perinephric abscess, sepsis,
 Urinary fistula, hypertension,
 Urinary extravasation, and urinoma
 Delayed complications include
 Bleeding, hydronephrosis,
 Calculus formation, chronic pyelonephritis,
 Hypertension, arteriovenous fistula,
 Hydronephrosis, and pseudoaneurysm.

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TREATMENT ALGORITHM