Renal Trauma Dr. Ibrahim Barghouth

Background 1-5% of all traumas Male to female ratio 3:1 Mechanism is classified as blunt or penetrating blunt trauma accounts 90-95% Traffic accidents accounts half of blunt renal injuries Renal lacerations and renal vascular injuries make up only 10-15% of blunt renal injuries

Background Renal artery occlusion is associated with a rapid deceleration injuries Rate of nephrectomy in recent wars is relatively high (25-33%)

Injury Calssification A total of 26 classifications have been presented in the literature in the past 50 years These are oriented to different criteria such as : 1.The pathogenesis ( blunt or penetrating ) 2.The morphological findings ( type and degree of lacerations ) 3.The clinical course ( nature and time of symptoms )

AAST renal injury grading scale GradeDescription of injury 1 Contusion or non-expanding subcapsular hematoma No laceration 2 Non-expanding perirenal hematoma Cortical laceration < 1 cm deep without extravasation 3 Cortical laceration > 1cm without urinary extravasation 4 Laceration : through corticomedullary junction in to collecting system Or Vascular : segmental renal artery or vein injury with contained hematoma 5 Laceration: shatered kidney Or Vascular : renal pedicle injury or avulsion

Initial emergency assessment Securing of the airway Controlling any of the external bleeding Resuscitation of shock Physical examination is carried out during stabilization

History and physical examination Direct history is obtained from conscious patients Witness and emergency personnel can provide information regarding unconscious patients

Possible indicators of major renal injury

The following findings on physical examination may indicate possible renal involvement : 1.Hematuria 2.Flank pain 3.Flank ecchymosis 4.Flank abraisions 5.Fractured ribs 6.Abdominal distension 7.Abdominal mass 8.Abdominal tenderness

Guidelines on laboratory evaluation Urine from a patient with suspected renal injury should be inspected grossly and then by dipstick analysis Serial hematocrit measurement indicates blood loss ( renal or associated injuries ? ) Creatinine measurement reflects renal function preior to the injury

Guidelines on radiographic assessment Blunt trauma patients with macroscopic or microscopic hematuria ( at least 5 rbc/hpf ) with hypotension (systolic blood pressure < 90 mmHg ) should undergo radiographic evaluation Radiographic evaluation is also recommended for all patients with a history of rapid deceleration injury and /or significant associated injury All patients with any degree of hematuria after penetrating abdominal or thoracic injury require urgent renal imaging Ultrasonography can be informaive during the primary evaluation of polytrauma patients and for the follow-up of the recuperating patients

Guidelines on radiographic assessment A CT scan with enhancement of intravenous contrast material is the best imaging study for diagnosis and staging renal injuries in hemodynamically stable patients Unstable patients who require emergency surgical exploration should undergo a one-shot IVP with bolus intravenous injection of 2ml/kg contrast Formal IVP, MRI, and radiographic scintigraphy are reliable alternative methods of imaging renal trauma when CT is not available Angiography can be used for diagnosis and simultaneous selective embolization of bleeding vessels

Computed tomography scan of right kidney following stab wound laceration with urine extravasation, large right retroperitoneal hematoma

Treatment Non-operative management is the treatment of choice for the majority of renal injuries The overall exploration rate for blunt trauma is less than 10% The overall rate of patients who have a nephrectomy during exploration is around 13%

Guidelines on management of renal trauma Stable patients following grade 1-4 blunt renal trauma, should be managed conservatively : Bed-rest, hydration and antibiotics, and continuous monitoring of vita signs until hematuria resolves Stable patients, following grade 1-3 stab and low velocity-gunshot wounds after complete staging, should be selected for expectant management

Guidelines on management of renal trauma Indications for surgical management include : 1.Haemodynamic instability 2.Exploration for associated injuries 3.Expanding or pulsatile perirenal hematoma identified during laparotomy 4.A grade V injury 5.Incidental finding of pre-existing renal pathology requiring surgical therapy Renal reconstruction should be attempted in cases where the primary goal of controlling hemorrhage is achieved and sufficient amount of renal parenchyma is viable

Guidelines on post-operative management and follow-up Repeat imaging is recommended for all hospitalized patients within 2-4 days following renal trauma Nuclear scintigraphy before discharge from the hospital is useful for documenting functional recovery Within 3 months of major renal trauma, patients follow-up should involve : 1.Physical examination 2.Urinalysis 3.Individualized radiological investigation 4.Serial blood pressure measurement 5.Serum determination of renal function Long-term follow-up should be decided on a case-by-case basis

Complications Early complications : Bleeding, infection, perinephric abscess, sepsis, urinary fistula, hypertension, urinary extravasation and urinoma Delayed complications : Bleeding, hydronephrosis, calculus formation, chronic pyelonephritis, hypertension, arteriovenous fistula, and psuedoaneurism

Guidelines on management of complications Complication following renal trauma require a thorough radiographic evaluation Medical management and minimal invasive techniques should be the first choice for the management of complications Renal salvage should be the aim of surgeon for patients in whom surgical intervention is necessary

Guidelines on management of paediatric trauma Indications for radiographic evaluation of children suspected for renal trauma include : 1.Blunt and penetrating trauma patients with any level of hematuria 2.Patients with associated abdominal injuries regardless of the urinalysis findings 3.Patients with normal urinalysis who sustained a rapid deceleration events, direct flank trauma, or fall from height Ultrasonography is considered a reliable method of screening and following blunt renal injuries CTscans is the imaging study of choice for staging renal injury Haemodynamic instability and a diagnosed grade V injury are absolute indications for surgical exploration

Guidelines on management of polytrauma patients with associated renal injury Polytrauma patients with associated renal injuries should be evaluated on the basis of the most threatening injury In cases where the decision for surgical intervention is made, all associated injuries should be evaluated simultaneously The decision for conservative management should regard all injuries independently