Analysis of battle and non-battle traumatic renal injuries: a 6-year experience in a conict zone in Afghanistan

Renal trauma occurs in 1-5% of all trauma cases [1]. The kidney is considered the most commonly injured genitourinary organ, with a male to female ratio of 3:1 [2]. Gunshot wounds are the most common causes of penetrating injuries and have the tendency to become more severe and less predictable than blunt trauma. Bullets cause destruction of the parenchyma and are often associated with multiorgan injuries [3]. Penetrating injury contributes to direct disruption of the parenchyma, collecting system, or vascular pedicle tissues.

The left side of the abdomen is mostly susceptible to trauma, especially on the battle eld, due to the combat posture of the soldier.

Methods
The study was conducted from September 2009 to March 2014. A total of 1266 combat trauma patients were treated in two health centers in the Forward Operating Base, Ghazni, Afghanistan, from the 6 to 14 rotation of the Polish Military Contingent (Medical Support Team Role 2 and Forward Surgical Team). 41 of whom had combat renal injuries. Forty-one (3.23%) patients were enrolled into the study and were reviewed retrospectively. The cohort study involved soldiers, 40 (97%) males and 1 (3%) female. The mean age of patients was 29 years. In most cases, renal injury was concomitant with multiorgan injury.
The following features of renal injury were assessed: etiology or mechanism of trauma, PATI score (Penetrating Abdominal Trauma Index) in penetrating trauma, ISS (Injury Severity Score), treatment method, and multiorgan injury. In addition, it was determined a left-handedness and a right-handedness due to a correlation between side of renal injury and a combat posture of a soldier. PATI and ISS scores were perioperatively calculated to determine the method of treatment and to predict possible postoperative complications respectively.
A radiography of the chest was performed, as well as a focused assessment with sonography for trauma (FAST) exam. In the conditions of battle eld, an access to computed tomography was limited, and the fast diagnostics was necessary. The FAST exam was used to determine the presence or otherwise of blood in the pericardium and/or peritoneum of unstable patient. A negative result, however, did not rule out the possibility of intra-abdominal organ injuries, particularly, hollow-organ injuries.
Statistical analyses were conducted using Stata/IC 14.2. The Kaplan-Meier survival analysis was used to determine the renal salvage rate employing PATI score as an indicator of nephrectomy. Results are expressed on the graph with hazard ratios and 95% con dence intervals.

Discussion
The damage of tissues caused by penetrating bullets depends on the intensity of impact. The complex interactions of the projectile with the various tissues result in a wide range of ballistic injury patterns and a characteristic bullet trajectories.
Knowledge of the speci c mechanisms that lead to increased tissue destruction will assist in the recognition of the less common injuries involving high-intensity impact, which are also associated with a higher risk of infectious complications [10]. According to Taş et al., injuries to the left kidney signi cantly occurred more often than injuries to the right kidney.
However, the mean PATI score and the number of injured organs and blood transfusions did not differ by which side the injury occurred. In scienti c publications, different opinions exist with respect to the side of renal injury. In the case of blast effects, the authors observed intraoperatively that the liver has a protective effect on the right kidney such that it may sustain the impact of the blast injury. In renal and liver injuries not directly attributable to projectile, although the blast effect caused higher-grade liver injuries, it was observed that a lower-grade right kidney injury occurred at the same time [11]. Voelzke  In our study, 17 nephrectomies procedures were performed, 13 of which involved the left kidney alone. In addition, the most commonly injured abdominal organs were the spleen (in 10 patients) and the large bowel (in 7 patients). These results con rmed our hypothesis that the left side of abdomen is most often susceptible to trauma especially on the battle eld. This is because the bandolier that holds the ammunition is strapped on the right side, thereby providing adequate protection to that side of abdomen. The renal salvage rate was 61.36% and overall survival rate was 90.24%.

Conclusions
The left side of the abdomen is more often susceptible to trauma and as a result, there are numerous multiorgan injuries involving the abdomen, spleen, large bowel, and left kidney. The combat posture of a soldier on the battle eld determines the abdominal injuries of the left side. This is because the bandolier that holds the ammunition is strapped on the right side, thereby protecting that side from injury.

Declarations
Ethics approval and consent to participate The study was quali ed as noninterventional observation study. Moreover, the researchers did not transfer the personal data of observed patients to the organizer. Thus, this study did not require approval by Ethics Commitee and registration in Central Register of Clinical Studies.

Consent for publication
Not applicable.

Availability of Data and Materials
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declares that they have no nancial and non-nancial competing interests.

Funding
There is no funding.
Authors' Contribution TZ conceived the idea for the study. TZ and RB contributed to the design of the research. RB was involved in data collection.
TZ analyzed the data. All authors edited and approved the nal version of the manuscript.
13. Williams M, Jezior J. Management of combat-related urological trauma in the modern era. Nature Reviews Urology.