This is the first study showing analyses of colon battlefield injury in patients from the Ukrainian Armed Forces. This study highlighted various clinical outcomes of colon injury in case of damage by modern hollow-point bullets as compared to conventional types of shape-stable bullets. The results from this study showed severe trauma and a higher mortality rate for patients injured by the hollow-point bullets. Our findings shed the light on clinical features and management of gunshot colon injury, which might be useful in further clinical application for both civil and combat casualties.
Similar to other reports we showed that majority of the patients were evacuated within the “golden hour” to Level II and treated according to with principle of damage control surgery, which is standard protocol for Ukrainian military medicine and in line with other studies of gunshot abdominal trauma (12–15).
Although we have not found publications with a specific reference to the hollow-point bullet injury vs. shape-stable bullets, evidence from our and other experimental studies confirms our data concerning increased tissue damage by such kind of weapon (7, 8, 16, 17). Hollow-point bullets are moved with irregular paths causing longer length to operate as its crushing edge, resulting in a large permanent cavity to increase the damage to tissues (8). Our findings demonstrate that majority of patients had concurrent damage to other organs, which supports the abovementioned hypothesis.
In line with Busić et al. and Elfaedy et al., we also demonstrated a high incidence of hemorrhagic shock in our patients suggesting such gunshot complications as a common event (10, 18). Also, we have shown a higher frequency of hemorrhagic shock in patients injured by hollow-point as compared to shape-stable bullets, which is another evidence of severe trauma from the modern weapon. The higher severity of shock is associated with higher levels of ischemia and hypoxia of colon tissues, which act to increase bacterial colonization, resulting in a higher risk for anastomosis leak or failure (10, 19).
Similar to other reports, the left colon part (i.e. splenic colon flexure, descending and sigmoid colon) and middle colon (ascending and descending colon) were frequently injured as compared to other sites (1, 10, 20–23). The importance to note that colon part injury is related to a higher risk of fecal diversion. Our findings are consistent with Watson et al., who showed the high risk of fecal diversion in combat patients with left-side colon injury due to high-energy projectiles. However, we also suggest considering the bullet type (i.e. the hollow-point bullet) as an additional factor to increase the damage to the tissues. Our findings would seem to suggest that mechanisms of injury by modern bullets may affect all colon parts without relation to bullet type.
Unlike other research carried out in this area, we showed multiple injuries to the colon in 58% of patients, which is higher compared to other combat cohorts. For example, Oosthuizen et al. showed 12% and Steele et al. 15% of multiple injuries in patients diagnosed with more than one injury to the colon in the study of non-combat trauma (20, 22). Cardi et al. demonstrated multiple segment injuries in both large and small bowel in 21.3% of the patients (24). However, our finding is in line with Bothaigi et al. who showed 64 colorectal wounds in 56 patients in the study of abdominal battlefield trauma (21). These differences can be explained by the frequent application of the hollow-point bullets in our cohort as compared to others.
Analyses of CIS showed that 48.2% of patients had CIS II or greater in the entire cohort. Our observation is consistent with Fealk et al. reporting 59% of patients to have CIS > 2 as well as with Miller et al. who showed a mean CIS of 2.4 (23, 25). In this study, we showed no patients to have CIS I, but a higher frequency of CIS III and IV among individuals injured by the hollow-point bullets, as compared to shape-stable bullets. This could potentially lead to a significant role in expanding bullets in severe colon trauma.
The overall rate of colostomy in our cohort is in contrast to other reports: Steele (33%), Glasgow (36.3%), Watson (36.9%), Oosthuizen et al. (50%) or Mitchao et al. (2.5%) (1, 9, 14, 22, 26). However, a similar proportion of colostomies was also reported by Cardi et al., showing it in 13.6% of the patients with colorectal wounds in case of high fecal spread or at damage control surgery (24). As judged from the analyses of other series and our experience, there are multiple factors to play a role in surgeons’ decision to choose a certain operative approach in each situation, including a colostomy. The observed proportion of colostomies could be attributed to severe colon trauma, which is in line with previously published series (14, 15, 20). We agree with other researchers suggesting avoiding colostomy and performing primary closure in selected patients with injury by shape-stable bullets (14, 15, 20). However, colon injury by the hollow-point bullets is associated with more severe trauma as showed by our results, thus decision to perform colostomy was made after evaluation of the abdomen in the context of damage control surgery.
Mortality is usually high in patients with gunshot colon wounds, mainly because of multiorgan injury and severe hemorrhagic shock (14). In our study, we showed lethal outcomes in 21.4% of patients which is close to data in studies of Oosthuizen et al. who showed overall mortality of 26%, and Vertrees et al. 29% of patients with gunshot wounds (10, 15). In contrast, Elfaedy et al. demonstrated mortality of 6.9%, however, in that study 40% of patients were not in hemorrhagic shock, which is a risk factor for death in patients with an abdominal gunshot injury, including colon (10). Glasgow et al. showed overall mortality of 9.5% (9). Steel et al showed 17.7% mortality in combat patients (22). Zero colon-related mortality was shown by Bothaigi et al. and Mitchao et al. (21, 26). Cardi et al. showed a mortality of 12.8%, with hemorrhagic shock as the most frequent cause of death (24). According to published series, mortality is reported high in multiple gunshot wounds, as also shown in this study (27).