Characteristics of cerebral gunshot injuries in the rural setting.

The rural CGW population has not yet undergone the metamorphosis experienced by its urban counterparts. Reminiscent of a past era, suicides far outweight homicides. Although many rural firearm injuries involve hunting accidents, these comprise only a small fraction of CGW at best. Similarly, although many rural firearm injuries involve shotguns or rifles, few CGW result from these weapons. Although the number of patients is small, those with shotgun or rifle injuries manifest lower mortality rates. The authors have confirmed the notion that caliber of civilian weapons is difficult to correlate with outcome. The geographic size of the rural catchment area is an important consideration because it must select a population able to withstand transfer. The authors noted an inverse relationship between length of time before arrival at the facility and mortality. The selection phenomenon probably accounts for the reduced mortality found in the authors series versus most others. Prognostic features of individual gunshot wounds are likely to be similar among varied populations when circumstances of the injury are matched. Thus, one expects similar features on initial examination and CT scan to have similar predictive value. The authors confirmed that CGS and specific deficits were strong predictors of outcome. No patient with a GCS score of 5 or less on admission survived. Absent pupillary response, absent brain stem function, presence of respiratory drive or cough only, and posturing were strong indicators of impending death. The authors confirmed the prognostic value associated with CT evidence of intraventricular hemorrhage, transventricular trajectory, transtentorial herniation, massive edema, and bihemispheric injury. Interestingly, presence of extensive facial fractures, an indicator of trajectory, suggested better outcome. Subarachnoid hemorrhage did not reach prognostic significance. Roughly half of the authors' patients had positive serum ethanol levels, although the test was unable to discern prognosis. Abnormality of any coagulation parameter and frank disseminated intravascular coagulation were correlated with poor outcome. Likewise, thrombocytopenia occurring within the first 24 hours was an indicator of poor prognosis. Although prophylactic antibiotics were not used in all cases, the authors encountered no deep or superficial infections in surviving patients. The prevalence of seizures in the authors' series despite prophylactic AED is unusually high. This feature merits further study.