Studies: Manage blunt renal trauma conservatively

January 1, 2009

Two studies of blunt kidney trauma, one from Switzerland and one from the United States, reached essentially the same conclusion: Conservative management is likely to be the best path when confronting most cases of blunt renal trauma.

Bern, Switzerland-Two studies of blunt kidney trauma, one from Switzerland and one from the United States, reached essentially the same conclusion: Conservative management is likely to be the best path when confronting most cases of blunt renal trauma.

"I don't remember when we did our last embolization," Pascal Zehnder, MD, a resident in urology, University of Bern, Switzerland, told Urology Times.

"When a grade 2 to 4 trauma comes into our clinic, urologists involved say, do not embolize. Grade 3 to 5 injuries are different situations. But if you have grade 2 to 4, stabilize with blood transfusion. Bleeding will stop as long as Gerota's fascia is intact. If you take a conservative approach, you save kidneys," he said.

"We had from 73% to 75% do very well with such management. However, the most common reason to go to open management remains hemodynamic instability," said Eric Umbreit, MD, a urology resident at the Mayo Clinic, where he and colleagues focused on management of grade 4 blunt trauma in children.

The Bern study, led by Urs Studer, MD, looked at 170 patients who had presented to the institution with American Association for the Surgery of Trauma (AAST) grade 2 to 4 blunt renal trauma between 1973 and 2007. The 34-year span was separated into three periods: 1973 to 1988 (71 patients), 1989 to 1995 (39 patients), and 1996 to 2007 (60 patients). A trend toward conservative management was clear. During the first period, 40 patients (56%) underwent open surgery, 32 of whom had a total or partial nephrectomy. By comparison, none of the 60 patients in the 1996-2007 period underwent open surgery.

Looking back at the 1973-1989 and 1989-1995 periods, the authors stated, "Most of these kidneys could have been saved with primary conservative management, especially considering that none of the group C (1997-2007 period) underwent open surgery, even though this group had a considerably higher proportion of grade 4 trauma patients."

"However, there is a limitation to our study," Dr. Zehnder said. "There is a lack of follow-up on these last 60 patients. In the first two cohorts, we lost 41 kidneys, and in the last 10 years, all kidneys were saved, but I cannot say whether any of these has an impairment."

The Mayo Clinic study, led by Douglas Husmann, MD, began with a 4-year-old girl who fell on a monkey bar.

"She presented with grade 4 renal injury, which we initially followed with non-operative management," Dr. Umbreit said. "We had to intervene about 48 hours after she presented, and the case prompted us to question what the literature held about the subject."

The Mayo team culled data on 91 children, 18 years of age or younger, who had sustained AAST grade 4 lacerations. All of the children underwent initial conservative management. No intervention was required in 66 patients (73%); however, of these, 14 (15%) developed symptomatic urinoma. Eleven of the 14 were successfully managed by percutaneous drainage or ureteral stent placement.

Hemodynamic instability in 11 (12%) of the 91 children required angiographic infarction or surgical exploration. This led to total nephrectomy in three patients and partial nephrectomy in five. The kidneys were salvaged in the remaining three.

Both studies were presented at the AUA annual meeting in Orlando, FL.