Epidemiology of cranial infections in battlefield-related penetrating and open cranial injuries

BACKGROUND Penetrating brain injuries are a potentially lethal injury associated with substantial morbidity and mortality. We examined characteristics and outcomes among military personnel who sustained battlefield-related open and penetrating cranial injuries during military conflicts in Iraq and Afghanistan. METHODS Military personnel wounded during deployment (2009-2014) were included if they sustained an open or penetrating cranial injury and were admitted to participating hospitals in the United States. Injury characteristics, treatment course, neurosurgical interventions, antibiotic use, and infection profiles were examined. RESULTS The study population included 106 wounded personnel, of whom 12 (11.3%) had an intracranial infection. Posttrauma prophylactic antibiotics were prescribed in more than 98% of patients. Patients who developed central nervous system (CNS) infections were more likely to have undergone a ventriculostomy (p = 0.003), had a ventriculostomy in place for a longer period (17 vs. 11 days; p = 0.007), had more neurosurgical procedures (p < 0.001), and have lower presenting Glasgow Coma Scale (p = 0.01) and higher Sequential Organ Failure Assessment scores (p = 0.018). Time to diagnosis of CNS infection was a median of 12 days postinjury (interquartile range, 7-22 days) with differences in timing by injury severity (critical head injury had median of 6 days, while maximal [currently untreatable] head injury had a median of 13.5 days), presence of other injury profiles in addition to head/face/neck (median, 22 days), and the presence of other infections in addition to CNS infections (median, 13.5 days). The overall length of hospitalization was a median of 50 days, and two patients died. CONCLUSION Approximately 11% of wounded military personnel with open and penetrating cranial injuries developed CNS infections. These patients were more critically injured (e.g., lower Glasgow Coma Scale and higher Sequential Organ Failure Assessment scores) and required more invasive neurosurgical procedures. LEVEL OF EVIDENCE Prognostic and Epidemiological; Level IV.