Surgical management of blunt renal injury consists of total nephrectomy and has become increasingly rare with the increased efcacy of expectant management and advance­ment in minimally invasive techniques. One large study from 1995 found that surgical intervention was required in fewer than 10% of cases of renal injury [30]. Correlation between AAST renal injury grade and hemodynamic instability was the only demonstrated predictor of need for surgery in a large prospective single center study, with surgical management required in 11% of grade IV and 48% of grade V renal inju­ries [29]. Penetrating trauma to the kidney is nine times less common than blunt trauma [31] and often warrants surgical exploration [29].

Treatment failure is dened as the need for operative manage­ment after an attempt of non-operative management. Patients are typically monitored as inpatients for at least 1–3 days [2]. Predictive factors for failure of NOM include high grade of injury and preexisting underlying splenic disease [13]. Although delayed splenic rupture is an important risk of NOM for splenic trauma, follow-up imaging in the inpatient setting is a controversial practice with only a minority of surveyed trauma surgeons performing routine follow- up CT [14]. Follow-up imaging may detect delayed vascular injury such as splenic pseudoaneurysm in 6% of cases [14]. Delayed splenic rupture most frequently occurs 4–8days after injury and carries an increased mortality rate of 5–15%, compared to a 1% mortality rate for overall acute splenic injury [15]. A recent study demonstrated decreased incidence of delayed splenic rupture with the routine use of follow- up CT imaging obtained 48h after NOM [14]. Classically, splenic rupture is characterized by left hemidiaphragm elevation, left lower lobe atelectasis, and left pleural effusion, although this triad is unreliable and often absent [15]. Additional major com­plications include splenic infarction, splenic abscess, and contrast-induced nephropathy. Minor complications include pleural effusion and post- embolization syndrome. Post­embolization syndrome (PES) presents in the rst 3days and is characterized by fever, leukocytosis, nausea, generalized pain, and/or u-like symptoms. Treatment is supportive, and the condition is self-limited. Routine post-discharge follow­up imaging is not recommended [2].

The success of TAE to control bleeding as part of NOM trauma has been reported as 81–100% [23]. TAE is also uti­lized for hemorrhage control following laparotomy in the setting of hepatic trauma. A systematic review of the litera­ture reported the need for postoperative TAE in 12–28% of surgical patients [23].