High Rates of Failure Following Blunt Renal Injuries - Springer Link

4 downloads 0 Views 188KB Size Report
Dec 29, 2010 - Abstract. Background Nonoperative management (NOM) of solid organ injury after blunt trauma is now standard. Recently, angioembolization ...
World J Surg (2011) 35:520–527 DOI 10.1007/s00268-010-0927-0

Angiointervention: High Rates of Failure Following Blunt Renal Injuries Jay Menaker • Bellal Joseph • Deborah M. Stein Thomas M. Scalea



Published online: 29 December 2010 Ó Socie´te´ Internationale de Chirurgie 2010

Abstract Background Nonoperative management (NOM) of solid organ injury after blunt trauma is now standard. Recently, angioembolization (AE) has been used to extend NOM. Few data exist on evaluating NOM of blunt renal injuries (BRIs). We sought to determine the overall efficacy of NOM as well as the outcome of AE in patients with BRI. Methods The trauma registry was used to identify all patients with BRI between January 2002 and December 2008. Medical records were reviewed for demographics, grade of injury, use of angiographic intervention, and outcome. Results A total of 434 patients with BRI were identified, 416 of whom had planned NOM; 337 (81%) patients were successfully managed without further intervention for their BRI. In all, 79 (19%) patients underwent angiography; 22 (27.8%) of these patients underwent AE, and 6 (27.2%) failed 1.2 ± 0.8 days after AE. Patients who failed AE had a significantly higher blood transfusion requirement during the first 24 h of admission (p = 0.01). Seven patients not embolized failed 1.9 ± 1.9 days after angiography. Thus, of the 79 patients having angiography, 13 (16.5%) failed and required laparotomy to treat their BRIs. Overall failure rate of NOM was 3.1% (13/416). Patients who failed angiography, with or without AE, required more blood during the first 24 h after admission (p = 0.03). J. Menaker (&)  D. M. Stein  T. M. Scalea Department of Surgery, University of Maryland School of Medicine, Division Trauma/Critical Care, R Adams Cowley Shock Trauma Center, 22 South Greene Street, T1R60, Baltimore, MD 21201, USA e-mail: [email protected] B. Joseph University of Arizona Medical Center, Tucson, AZ, USA

123

Conclusions NOM of BRI is safe and effective, with an overall failure rate of 3.1%. However, angiography with or without AE has substantial failure rates. Patients with higher-grade injuries and active vascular extravasation on admission computed tomography scan also fail NOM regardless of therapy. The blood transfusion requirement during the first 24 h may indicate who will require operative intervention following angiography. Close observation and/or early laparotomy are wise for these high-risk patients.

Introduction Blunt trauma is responsible for 80–90% of all renal injures [1, 2]. Renal injuries occur in approximately 10% of all abdominal trauma [3]. Most of these injuries are minor and can be successfully managed with observation alone [4, 5]. However, 20–40% of blunt renal injuries (BRIs) are major lacerations or involve the pedicle [2]. Most would agree that those who present with hemodynamic instability require immediate operative intervention. Controversy exists regarding the management of the hemodynamically stable patient with a high-grade BRI. Some advocate that early aggressive surgical intervention decreases morbidity and the need for delayed nephrectomy [6–8]. Others believe that conservative management allows most renal injuries to resolve without surgical intervention. Additionally, conservative management leads to lower nephrectomy rates and fewer complications [9–11]. Nonoperative management (NOM) for hemodynamically stable blunt liver and spleen injuries is the standard of care. Angiographic embolization for high-grade liver and spleen injuries has been shown to be a safe and effective therapeutic intervention while decreasing the need for

World J Surg (2011) 35:520–527

operative intervention [12, 13]. NOM for high-grade BRI began with the aim of reducing the high rates of potentially unnecessary nephrectomies [3, 9, 10]. The use of angioembolization (AE) for high-grade renal injuries has been advocated as an effective adjunct in the salvage of patients with high-grade renal lacerations; however, most studies have small numbers of patients [14–19]. We sought to determine the overall efficacy of NOM as well as the outcome of AE in patients with BRIs.

Patients and methods This retrospective chart review was performed at the R Adams Cowley Shock Trauma Center at the University of Maryland Medical Center in Baltimore, Maryland. The trauma registry was used to identify all patients between January 2002 and December 2008 with an admission diagnosis of BRI. Medical records were reviewed to stratify those patients undergoing immediate operative exploration versus those who had planned NOM with evaluation by computed tomography (CT). All CT scans were then reviewed, and a grade of renal injury was assigned based on the Organ Injury Severity Scale of the American Association for the Surgery of Trauma (AAST-OIS) [20]. Patients evaluated by CT scan were divided into those managed with observation alone and those who had subsequent angiography. During the study period, no protocol existed with specific indications for angiography in patients with BRI. Routine angiography was not performed for BRI regardless of the grade. In general, angiography was performed during the study period for specific CT findings— active vascular extravasation (AVE), associated solid organ injuries requiring angiography, high-grade renal injuries— or at the discretion of the primary attending trauma surgeon. Patients subjected to angiography were further divided into those undergoing intervention with embolization and those who did not. Medical records were reviewed for demographics, admission vital signs, hospital length of stay (HLOS), results of angiography, and outcome. The institutional review board at the University of Maryland School of Medicine approved the study.

Results A total of 434 patients with BRI were identified during the study period (1.2%) (Table 1, Fig. 1). The mean age was 33.5 ± 16.7 years, and 308 patients (71.0%) were male. The overall mean injury severity score (ISS) was 28.3 ± 14.1, and the mean HLOS was 10.8 ± 13.0 days. The mean grade of renal injury was 2.6 ± 1.0. High-grade

521 Table 1 Study population Parameter

No.

Blunt renal injury

434

Embolized

22*

Not embolized

58*

Angiography

79

Observation alone

337

Immediate operative intervention

18

Nonoperative management

416

*Bilateral renal angiograms were performed in one patient Blunt renal injury (BRI) N=434 Immediate operative intervention N=18

Non-operative management N=416

Observation alone N=337

Angiography N=79

Embolized N=22*

Not embolized N=58*

Fig. 1 Study population algorithm

(C3) renal injuries were present in 37.3% of patients. Overall mortality rate was 7.8%, none directly related to BRI. In all, 18 (4.1%) patients required immediate operative intervention. The mean age of patients requiring immediate operative intervention was 31.4 ± 11.9 years, with a mean ISS of 34.8 ± 16.3. Overall, 89% of those requiring immediate operative intervention had a highgrade renal injury with an overall mean grade of 4.2 ± 1.0. The mean HLOS was 14.3 ± 17.2 days, with a 22.2% mortality rate. Altogether, 416 (95.9%) patients had planned NOM for BRI. The mean age of those with planned NOM was 33.6 ± 16.9 years. The mean ISS was 28.0 ± 13.9, and the mean grade of renal injury was 2.5 ± 1.0. The mean HLOS was 10.7 ± 12.8 days. When comparing patients who required immediate operative intervention and those who had planned NOM, those treated with immediate surgical exploration had a statistically lower admission systolic blood pressure (p = 0.003), higher incidence of hypotension on admission (p \ 0.001), high-grade renal injury (p \ 0.001), higher mean grade of injury (p \ 0.001), and

123

522

World J Surg (2011) 35:520–527

Table 2 Immediate surgical intervention versus planned nonoperative management of BRI Parameter

All (n = 434)

Immediate surgical intervention (n = 18)

Planned NOM (n = 416)

Age (years)

33.5 ± 16.7

31.4 ± 11.9

33.6 ± 16.9

Sex: male

308 (71.0%)

13 (72.2%)

295 (70.6%)

Hypotension on admissiona

8 (8.8)

6 (33.3%)

30 (7.2%)

p

0.6 0.9 \0.001

Admission SBP

129.7 ± 31.1

109.0 ± 35.8

131.3 ± 29.8

0.003

Admission HR

98.1 ± 23.7

96.2 ± 19.1

98.5 ± 23.4

0.7

ISS

28.3 ± 14.1

34.8 ± 16.3

28.0 ± 13.9

0.04

TRISS Renal injury (AAST-OIS)

0.85 ± 0.24

0.82 ± 0.29

0.85 ± 0.24

0.6 \0.001

Grade 1

47 (10.8%)

0

47 (11.3%)

Grade 2

225 (51.8%)

2 (11.1%)

223 (53.6%)

Grade 3

42 (9.7%)

1 (5.6%)

41 (9.9%)

Grade 4

111 (25.6%)

7 (38.9%)

104 (25.0%)

Grade 5

9 (2.1%)

8 (44.4%)

1 (0.2%)

Average

\0.001

2.6 ± 1.0

4.2 ± 1.0

2.5 ± 1.0

LOS (days)

10.8 ± 13.0

14.3 ± 17.2

10.7 ± 12.8

Blood transfusionb (units)

2.2 ± 6.2

12.2 ± 16.6

1.8 ± 4.9

\0.001

Total deaths

34 (7.8%)

4 (22.2%)

30 (7.2%)

0.1

0.3

BRI blunt renal injury, NOM nonoperative management, SBP systolic blood pressure, HR heart rate, ISS Injury Severity Score, TRISS Trauma Injury Severity Score, AAST-OIS American Association for the Surgery of Trauma–Organ Injury Scale, LOS length of stay in hospital a

Systolic blood pressure \90 mmHg

b

Units during first 24 h

higher packed red blood cell transfusion requirement during the first 24 h after admission (p \ 0.001) (Table 2). In all, 337 (81.0%) patients in the NOM group required no intervention for their BRI. No patients in this group died from their renal injuries. A total of 79 (19.0%) patients in the NOM group underwent angiography. Indications for angiography were AVE in 27 (34.2%) patients, high-grade renal injury in 42 (53.2%), and attending surgeon preference in the remaining 10 (12.6%). Table 3 compares those patients managed with no additional intervention for BRI and those requiring angiography. Patients selected for angiography had a significantly higher percentage of highgrade renal injuries than did those managed with observation alone. (p \ 0.001). Of note, one patient had bilateral renal injuries on angiography, requiring AE on one side and no intervention on the other. The overall failure rate of planned NOM for BRI was 3.1%. Of the 79 patients who underwent angiography, 22 required AE and 58 had no intervention performed. When these two groups were compared, no statistical difference was found (Table 4). The failure rate of AE was 27.2% (n = 6) occurring on mean postangiography day (PAD) 1.2 ± 0.8. Patients having no intervention at the time of angiography had a failure rate of 12.3% (n = 7). Failure occurred on mean PAD 1.9 ± 1.9. Table 5 indicates the reasons for the failure of NOM and operative findings.

123

Table 6 compares patients with unsuccessful AE requiring surgical exploration with those who needed no further intervention following AE. Patients failing AE had a significantly higher blood transfusion requirement during the first 24 h of admission (p = 0.01). Overall, 13 (16.5%) patients who underwent angiography failed (on mean hospital day 1.5 ± 1.5. Patients who failed angiography, with or without AE, required more blood during the first 24 h of admission (p = 0.03) (Table 7).

Discussion The kidney is the most frequently injured organ in the urogenital system; and blunt trauma is the most common mechanism of injury to the kidney, occurring in 80–90% of cases [1, 2]. In all, 8–10% of all intraabdominal injuries following trauma involve the kidney [3]. The incidence of BRI after trauma has been reported to be between 1.2 to 3.1% [1, 21, 22]. Our incidence of BRI is 1.2%, similar to previous reports. Most BRIs are minor and self-limiting and thus can be managed conservatively with good outcomes [4, 5]. However, up to 40% of BRIs are considered major, and the management of such injuries remains controversial as no one specific algorithm exists [2].

World J Surg (2011) 35:520–527

523

Table 3 No intervention versus angiography in patients with BRI Parameter

Planned NOM (n = 416)

No intervention (n = 337)

Angiography (n = 79)

p

Age (years)

33.6 ± 16.9

33.5 ± 16.7

34.1 ± 17.7

0.8

Sex: male

295 (70.6%)

240 (71.2%)

55 (69.6%)

0.6

Hypotension on admissiona

30 (7.2%)

22 (6.5%)

8 (10.1%)

0.27

Admission SBP

131.3 ± 29.8

132.8 ± 29.3

124.8 ± 31.0

0.03

Admission HR

98.5 ± 23.4

98.0 ± 23.2

100.8 ± 24.0

0.3

ISS

28.0 ± 13.9

27.2 ± 14.3

31.2 ± 11.6

0.02

TRISS Renal injury (AAST-OIS)

0.85 ± 0.24

0.85 ± 0.25

0.85 ± 0.21

0.9

Grade 1

47 (11.3%)

46 (13.6%)

1 (1.3%)

Grade 2

223 (53.6%)

212 (62.9%)

11 (13.9%)

Grade 3

41 (9.9%)

29 (8.6%)

12 (15.2%)

Grade 4

104 (25.0%)

50 (14.8%)

54 (68.4%)

Grade 5

1 (0.2%)

0

1 (1.3%)

2.5 ± 1.0

2.2 ± 0.9

3.5 ± 0.8

LOS (days)

Average

10.7 ± 12.8

10.2 ± 12.5

12.3 ± 13.5

Blood transfusionb (units)

1.8 ± 4.9

1.6 ± 5.0

2.3 ± 4.7

Failure on NOM

13 (3.1%)

0

13 (16.5%)

Total deaths

30 (7.2%)

23 (7.1%)

7 (8.9%)

a b

\0.001

\0.001 0.2 0.3 \0.001 0.6

Systolic blood pressure \90 mmHg Units during first 24 h

Table 4 Angiography in BRI: embolized versus nonnembolized Parameter

Angiography (n = 79)

Not embolized (n = 58a)

Embolized (n = 22a)

p

0.2

Age (years)

34.1 ± 17.7

32.3 ± 14.9

38.6 ± 23.2

Sex: male

55 (69.6%)

38 (66.7%)

18 (81.8%)

0.6

Hypotension on admissionb

8 (10.2%)

7 (12.1%)

1 (4.5%)

0.32

Admission SBP

124.8 ± 31.0

122.1 ± 31.5

132.3 ± 28.5

0.2

Admission HR

100.8 ± 24.0

103.6 ± 25.4

92.7 ± 17.8

0.07

ISS

31.2 ± 11.6

32.6 ± 11.9

28.2 ± 10.7

0.1

TRISS Renal injury (AAST-OIS)

0.85 ± 0.21

0.83 ± 0.23

0.88 ± 0.16

0.4

Grade 1

1 (1.3%)

1 (1.7%)

0

0.3

Grade 2

11 (13.9%)

9 (15.5%)

2 (9.1%)

Grade 3

12 (15.2%)

10 (17.2%)

2 (9.1%)

Grade 4

54 (68.4%)

38 (65.5%)

17 (77.3%)

Grade 5

1 (1.3%)

0

1 (4.5%)

3.5 ± 0.8

3.5 ± 0.8

3.8 ± 0.7

0.1

LOS (days)

Average

12.3 ± 13.5

13.7 ± 15.3

9.7 ± 6.5

0.2

Blood transfusionsc (units)

2.3 ± 4.7

2.0 ± 4.5

2.9 ± 5.1

0.5

Failure of angiography

13 (16.5%)

7 (12.1%)

6 (27.2%)

0.1

Total deaths

7 (8.9%)

6 (10.3%)

1 (4.5%)

0.4

a b c

Bilateral angiograms were performed in one patient Systolic blood pressure \90 mmHg Units during first 24 h

123

524 Table 5 Failure of angiography

ACS abdominal compartment syndrome, CT computed tomography

World J Surg (2011) 35:520–527

Patient

Embolized

Reason for failure

Operative outcome

1

Yes

Ongoing bleeding

Partial nephrectomy

2

Yes

Ongoing bleeding, pain, ACS

Partial nephrectomy

3

Yes

Ongoing bleeding, ACS

Nephrectomy

4

Yes

Pain, increased free fluid on CT

Partial nephrectomy

5

Yes

ACS

Nephrectomy

6

Yes

Ongoing bleeding

Nephrectomy

7

No

Bleeding (postheparin infusion)

Renorrhaphy

8

No

Ongoing bleeding, pain

Nephrectomy

9

No

Ongoing bleeding, pain, urine leak

Partial nephrectomy

10

No

Pain, increased free fluid on CT

Nephrectomy

11

No

Ongoing bleeding

Renorrhaphy

12

No

Ongoing bleeding

Renorrhaphy

13

No

Ongoing bleeding

Nephrectomy

Table 6 Successful versus failures of angioembolization in patients with BRI Parameter

Angiography with embolization (n = 22)

Successful (n = 16)

Failure (n = 6)

p

Age (years)

38.6 ± 23.2

43.1 ± 25.3

26.7 ± 9.5

0.1

Sex: male

18 (81.8%)

12(75.0%)

6 (100.0%)

0.2

Hypotension on admissiona

1 (4.5%)

1 (6.3%)

0

0.5

Admission SBP

132.2 ± 28.5

131.4 ± 30.6

134.5 ± 24.5

0.8

Admission HR

92.7 ± 17.8

92.1 ± 18.0

94.3 ± 19.1

0.8

ISS

28.2 ± 10.7

28.6 ± 10.4

27.2 ± 12.5

0.8

TRISS Renal injury (AAST-OIS)

0.88 ± 0.16

0.85 ± 0.18

0.96 ± 0.03

0.2

Grade 1

0

0

0

0.2

Grade 2

2 (9.1%)

1 (6.3%)

1 (16.7%)

Grade 3

2 (9.1%)

1 (6.3%)

1(16.7%)

Grade 4

17 (77.3%)

14 (87.5%)

3 (50.0%)

Grade 5

1 (4.5%)

0

1 (16.7%)

Average

3.8 ± 0.7

3.8 ± 0.5

3.7 ± 1.0

0.7

LOS (days)

9.7 ± 6.5

9.4 ± 7.4

10.5 ± 3.1

0.7

Blood transfusionb (units)

2.9 ± 5.1

1.3 ± 1.9

7.2 ± 8.3

0.01

Day of failurec

NA

NA

1.2 ± 0.8

NA

Total deaths

1 (4.5%)

1 (6.3%)

0

0.5

NA not available Systolic blood pressure \90 mmHg

a

b

Units during first 24 h

c

Days after angiography performed

The decision between surgical intervention and further diagnostic evaluation depends on the patient’s hemodynamics. Patients who are hemodynamically unstable undergo emergent laparotomy for direct hemorrhage control. If the kidney is the source of hypotension, the operative result is often nephrectomy. Of our 18 patients who underwent immediate operative intervention, 12 had immediate nephrectomy, 3 had renorrhaphy, 2 had no intervention for

123

their renal injury and 1 died of massive hemorrhage during exploration. Stable patients undergo further diagnostic evaluation with CT. Those found to have low-grade BRI on CT can be managed with observation alone and do not require further intervention [4, 5]. Numerous reports have demonstrated that when clinicians elect observation and supportive care, conservative management alone can effectively manage hemodynamically stable patients with BRI [6, 23–25].

World J Surg (2011) 35:520–527

525

Table 7 Successful versus failed angiography Parameter

Angiography with or without embolization (n = 79)

Successful

Failure

(n = 67a)

(n = 13a)

p

Age (years)

34.1 ± 17.7

35.0 ± 18.6

28.9 ± 10.7

Sex: male

55 (69.6%)

47 (70.1%)

9 (69.2%)

0.3 0.9

Hypotension on admissionb Admission SBP

8 (10.1%) 124.8 ± 31.0

7 (10.4%) 124.3 ± 31.9

1 (7.7%) 127.9 ± 25.2

0.8 0.7

Admission HR

100.8 ± 24.0

101.0 ± 24.3

98.7 ± 22.9

0.8

ISS

31.2 ± 11.6

31.7 ± 11.8

29.6 ± 11.7

0.6

TRISS

0.85 ± 0.21

0.84 ± 0.22

0.88 ± 0.17

0.5

Grade 1

1 (1.3%)

1 (1.5%)

0

0.2

Grade 2

11 (13.9%)

10 (14.9%)

1 (7.7%)

Grade 3

12 (15.2%)

10 (14.9%)

2 (15.4%)

Grade 4

54 (68.4%)

46 (68.7%)

9 (69.2%)

Grade 5

1 (1.3%)

0

1 (7.7%)

Average

3.5 ± 0.8

3.5 ± 0.8

3.8 ± 0.7

0.3

Renal injury (AAST-OIS)

LOS (days)

12.3 ± 13.5

12.2 ± 14.2

14.2 ± 10.2

0.6

Blood transfusionsc (units)

2.3 ± 4.7

1.8 ± 3.7

4.8 ± 7.7

0.03

Day of failured

NA

NA

1.5 ± 1.5

NA

Total deaths

7 (8.9%)

6 (9.0%)

1 (7.7%)

0.9

a

Bilateral renal angiograms were performed in one patient

b

Systolic blood pressure \90 mmHg

c

Units during first 24 h

d

Days after angiography performed

In 1973, Cass and Ireland reported at 75% success rate of NOM with observation alone for BRI [23]. Kristja´nsson and Pedersen demonstrated only a 55% success rate on observation alone in patients with BRI [6]. Two patients required delayed nephrectomy, four required partial nephrectomy, two required renorrhaphy, and one required hematoma drainage. Similar to our results, Toutouzas and colleagues reported an 84% success rate with observation alone in patients with BRI [24]. Half of the patients had minor injuries (grade 1 or 2), and the remainder had high-grade injuries. All of those who failed NOM had high-grade injuries. Thall and colleagues demonstrated 100% success using expectant management in a series of 11 patients with grade 3 BRI [25]. Additionally, Hagiwara and colleagues managed 23 patients with grade 1 or 2 BRI with observation and supportive care alone and had no failures [14]. Management of high-grade BRI in the stable patient is more controversial. Conservative management has been suggested by some and is believed to be safe and to lower the need for posttrauma nephrectomy [9–11]. The use of AE has been advocated and extended from the management of blunt spleen and liver injuries to BRI, with promising results [17, 19, 26]. The use of transcatheter AE to control acute renal hemorrhage was first reported by Bookstein and Goldstein in 1973 for the treatment of a

postbiopsy arteriovenous fistula [27]. Numerous reports of successful AE for bleeding following percutaneous renal procedures have followed [15, 16]. With the success of AE as an adjunctive procedure for the management of blunt spleen and liver injuries, its use has been extended to BRI in an effort to achieve hemostasis. Indications for angiography in our patients varied. Among those with AVE on CT, about 60% underwent angioembolization at the time of angiography. Fu and colleagues evaluated 26 patients with BRI and AVE on CT who underwent angiography [26]. In their study, 14 (53.8%) patients with AVE on admission CT had AE at the time of angiography. The authors suggested, and we agree, that the patients who had AVE on admission CT and did not require AE at the time angiography had a self-tamponade effect on their injury. In 2009, Nuss et al. attempted to identify CT findings that would predict the need for AE following renal trauma [28]. They evaluated 47 patients with BRI. Four patients who had AVE on CT scans and clinical signs of ongoing blood loss underwent angiography with AE. None required surgical intervention for ongoing hemorrhage. Four additional patients had AVE on CT scans and did not have angiography performed; they were successfully managed with conservative therapy alone. Despite only 50% of their patients having angiography

123

526

with evidence of AVE on CT scan, the authors concluded that AVE is an important radiographic indicator that is strongly associated with the need for angiography with AE. Overall, 79 of our study patients underwent angiography following BRI, 13 (16.5%) of whom eventually required operative intervention (Table 5), Sofocleous and colleagues performed angiography on 10 hemodynamically stable patients with BRI [29]. No patient required operative intervention for ongoing hemorrhage. Two patients required a second angiography for ongoing bleeding. Hagiwara and colleagues performed angiography on 21 patients with BRI [14]. One patient, with a grade 5 injury, was unable to be embolized and subsequently underwent nephrectomy. Eight patients, six grade 4 and two grade 3, had successful embolization. The remaining 12 patients had no intervention at the time of angiography and required no further intervention. The authors concluded that transcatheter AE is an effective, safe tool for avoiding unnecessary laparotomy in many cases of BRI. Breyer and colleagues described a grade 4 renal injury that was successfully managed with AE [17]. The 48-h follow-up CT scan demonstrated no AVE and a stable hematoma. Dinkel et al. performed AE on eight patients with grade 3 to 5 BRI [19]. Hemostatsis was achieved in all patients, and no further intervention was required. The authors concluded that AE may be used as an effective, minimally invasive means to control active renovascular bleeding. We found no statistical difference when we compared those whose angiography results were negative with those who had AE (Table 4). We do not have a good explanation for this. However, and more importantly, six patients who underwent AE failed and required operative intervention. This represents a 27.2% failure rate and is more than twice the rate of failure for those who had no intervention at the time of angiography. Additionally, those who failed AE had a statistically higher transfusion requirement during the first 24 h after admission (p = 0.01), recognizing that many of these patients had polysystem trauma and may have been transfused secondary to hemorrhage from nonrenal injuries. As the mean time of failure for these six patients was 29 h from the time of angiography, one can argue that these patients should never have undergone angiography and would have been better served with initial operative management. Seven (12.3%) patients who had angiography without AE failed NOM, requiring operative intervention. Six of the patients had clinical evidence of ongoing bleeding. The operative outcomes were three nephrectomies, one partial nephrectomy, and three renorrhaphies. The authors acknowledge that it is possible a second angiography session may have obviated the need for operative intervention in some of those patents. However, in general, we believe that operative exploration is the wisest choice for patients who bleed after attempted NOM.

123

World J Surg (2011) 35:520–527

Overall, 13 (16.5%) patients who underwent angiography as part of NOM failed and required surgical intervention. The failure rate among patients with a negative angiogram was 12.3%; it was 27.2% for those who underwent embolization. This rate of failure following angiography, particularly when embolization was used, is concerning and is reminiscent of some of the early work done with AE to treat splenic injuries. In that body of literature, the presence of pseudoaneurysm seen on CT scans was highly suggestive of a failure of simple observation [30]. However, pseudoaneurysms were commonly seen on follow-up CT that were not seen on the initial CT [31]. When superselective embolization was used to treat splenic injury, failure rates were similar to those associated with simple observation [32]. This suggests that vascular injuries may not be apparent on the initial radiographic evaluation but may increase in size over some days and then bleed. Proximal coil embolization, which would treat all injuries, including occult injuries, has been far more successful in obtaining splenic hemostasis [13, 33]. The same may be true in the kidney. Selective embolization is used after BRI as proximal embolization would almost certainly result in a nearly 100% incidence of major infarction to the kidney. Unlike the spleen, there are insufficient collaterals in the renal arterial circulation to maintain liability after proximal occlusion. Although venous injury that is not detected at the time of angiography is certainly a plausible explanation of the high failure rate, we doubt it is sufficient to explain failure rates this high. Instead, we believe it is more likely that this represents arterial injury not seen at the time of CT and/or angiography. The fact that patients failed a mean of 1.2 days after admission seems to argue for an untreated vascular injury. It is possible that a second angiogram would have revealed new areas of vascular injury. However, our practice has been to explore patients with evidence of bleeding after an attempt at NOM. Although nephrectomy is certainly an unfortunate outcome, it is definitive hemostasis and is well tolerated in the average young trauma patient. We believe it is preferable than to continue attempts at NOM that would require ongoing blood transfusions. Given our data, after angiography, any patient who requires more than 2 or 3 units of blood should be seriously considered for operation as it appears that these patients have a relatively high rate of failure of NOM.

Conclusions Renal injury after blunt trauma occurs in 1.2% of patients. Most BRI are minor injuries and can be managed with observation alone. For higher-grade injuries and patients

World J Surg (2011) 35:520–527

with AVE on the admission CT scan, angiography with AE provides an adjunctive therapy to minimize the need for operative intervention. Despite this point, patients elected to proceed to angiography, even without AE, still have substantial rates of failure requiring further intervention. The first 24-h blood transfusion requirement may indicate who will require operative intervention following angiography. This study has demonstrated that angiography plays an important role in the management of BRI, but patients who are selected for angiography following BRI warrant close observation. Additionally, for those patients requiring blood transfusions early in the course of NOM, exploration should be given real consideration.

References 1. Bretan PN Jr, McAninch JW, Ferdele MP et al (1986) Computerized tomographic staging of renal trauma: 85 consecutive cases. J Urol 136:561–565 2. Matthews LA, Spirnak JP (1995) The nonoperative approach to major blunt renal trauma. Semin Urol 13:77–82 3. Wessells H, Suh D, Porter JR et al (2003) Renal injury and operative management in the United States: results of a population-based study. J Trauma 54:423–430 4. Goff CD, Collin GR (1998) Management of renal trauma at a rural, level I trauma center. Am Surg 64:226–230 5. Nguyen HT, Carroll PR (1995) Blunt renal trauma: renal preservation through careful staging and selective surgery. Semin Urol 13:83–89 6. Kristja´nsson A, Pederson J (1993) Management of blunt renal trauma. Br J Urol 72:692–696 7. Cass AS, Luxenberg M (1983) Conservative or immediate surgical management of blunt renal injuries. J Urol 130:11–16 8. Wein AJ, Murphy JJ, Mulholland SG et al (1977) A conservative approach to the management of blunt renal trauma. J Urol 117: 425–427 9. Matthews LA, Smith EM, Spirnak JP (1997) Nonoperative treatment of major blunt renal lacerations with urinary extravasation. J Urol 157:2056–2058 10. Moudouni SM, Patard JJ, Manunta A et al (2001) A conservative approach to major blunt renal lacerations with urinary extravasation and devitalized renal segments. BJU Int 87:290–294 11. Altman AL, Haas C, Dinchman KH et al (2000) Selective nonoperative management of blunt grade 5 renal injury. J Urol 164: 27–30 12. Mohr AM, Lavery RF, Barone A et al (2003) Angiographic embolization for liver injuries: low mortality, high morbidity. J Trauma 55:1077–1081 13. Haan JM, Bochicchio GV, Kraner N et al (2005) Nonoperative management of blunt splenic injury: a 5-year experience. J Trauma 58:492–498 14. Hagiwara A, Sakaki S, Goto H et al (2001) The role of interventional radiology in the management of blunt renal injury: a practical protocol. J Trauma 51:526–531

527 15. Vignoil C, Lonzi S, Bargellini I et al (2004) Vascular injuries after percutaneous renal procedures: treatment by transcatheter embolization. Eur Radiol 14:723–729 16. Beaujeux R, Saussine C, Al-Fakir A et al (1995) Superselective endo-vascular treatment of renal vascular lesions. J Urol 153: 14–17 17. Breyer BN, McAninch JW, Elliott SP et al (2008) Minimally invasive endovascular techniques to treat acute renal hemorrhage. J Urol 179:2248–2253 18. Chatziioannou A, Brountzous E, Primetis E et al (2004) Effects of superselective embolization for renal vascular injuries on renal parenchyma and function. Eur J Vasc Endovasc Surg 28:201–206 19. Dinkel HP, Danuser H, Triller J (2002) Blunt renal trauma: minimally invasive management with microcatheter embolization: experience in nine patients. Radiology 223:723–730 20. Moore EE, Shackford SR, Pachter HL et al (1989) Organ injury scaling: spleen, liver, and kidney. J Trauma 29:1664–1666 21. Herschorn S, Radomski SB, Shoskes DA et al (1991) Evaluation and treatment of blunt renal trauma. J Urol 146:274–276 22. Baverstock R, Simons R, McLoughlin M (2001) Severe blunt renal trauma: a 7-year retrospective review from a provincial trauma centre. Can J Urol 8:1372–1376 23. Cass AS, Ireland GW (1973) Comparison of the conservative and surgical management of the more severe degrees of renal trauma in multiple inured patients. J Urol 109:8–10 24. Toutouzas KG, Karaiskakis M, Kaminski A et al (2002) Nonoperative management of blunt renal injury: a prospective study. Am Surg 68:1097–1103 25. Thall EH, Stone NN, Cheng DL et al (1996) Conservative management of penetrating and blunt type III renal injuries. Br J Urol 77:512–517 26. Fu CY, Wu SC, Chen RJ et al (2010) Evaluation of need for angioembolization in blunt renal injury: discontinuity of Gerota’s fascia has an increased probability of requiring angioembolization. Am J Surg 199:154–159 27. Bookstein JJ, Goldstein HM (1973) Successful management of postbiopsy arteriovenous fistula with selective arterial embolization. Radiology 109:535–536 28. Nuss GR, Morey AF, Jenkins AC et al (2009) Radiographic predictors of need for angiographic embolization after traumatic renal injury. J Trauma 67:578–582 29. Sofocleous CT, Hinrichs C, Hubbi B et al (2005) Angiographic findings and embolotherapy in renal artery trauma. Cardiovasc Interv Radiol 28:39–47 30. Thompson BE, Munera F, Cohn SM et al (2006) Novel computed tomography scan scoring system predicts the need for intervention after splenic injury. J Trauma 60:1083–1086 31. Davis KA, Fabian TC, Croce MA et al (1998) Improved success in nonoperative management of blunt splenic injuries: embolization of splenic artery pseudoaneurysms. J Trauma 44:1008–1015 32. Haan J, Scott J, Boyd-Kranis RL et al (2001) Admission angiography for blunt splenic injury: advantages and pitfalls. J Trauma 51:1161–1165 33. Sclafani SA, Shaftan GW, Scalea TM et al (1995) Nonoperative salvage of computed tomography-diagnosed splenic injuries: utilization of angiography for triage and embolization for hemostasis. J Trauma 39:818–827

123