Objective: To compare types and frequency of medical complications and comorbidities associated with violence-related penetrating traumatic brain injury (TBI) as compared to violence-related blunt TBI.
Method: Data were collected prospectively at four medical centers participating in the TBI Model Systems (TBIMS) of Care project. A total of 317 individuals met the inclusion criteria for the TBIMS (i.e., showed evidence of a TBI, were age 16 or older, presented to the TBIMS emergency department within 24 hours of injury, and received acute and rehabilitation services within the model system).
Main Outcome Measures: Frequency of medical complications and comorbid diseases.
Results: Patients with penetrating injuries suffered significantly higher rates of respiratory failure (P = .004), pneumonitis/pneumonia, (P = .002), skull fracture (P = .001), cerebrospinal fluid leak (P = .0005), and hypotonia (P = .001) than did patients with blunt injuries. Prediction of complications and comorbidities via multiple regression revealed that a penetrating violent injury and the severity of injury were independent predictors of a higher rate of medical complications, whereas age and gender did not account for unique variance in the equation.
Conclusions: Penetrating injuries are associated with higher rates of certain medical complications, especially to the pulmonary and central nervous systems. Acute care physicians and physiatrists must be prepared to treat these complications more often in patients with penetrating injuries.
In RECENT YEARS, traumatic brain injury (TBI) patients admitted to inpatient rehabilitation programs have become more and more medically complicated, owing, in part, to the pressures on acute care hospitals for decreased lengths of stay. Rehabilitation physicians have begun accepting patients onto their inpatient units earlier in the patients' recovery and are, therefore, encountering complications that once never would have been seen there. For this reason, rehabilitation practitioners have needed to identify and treat progressively more medical complications and to consider them amongst the factors influencing functional outcome. Anecdotally, clinicians have noted that patients with penetrating injuries suffer higher rates and different types of medical complications than those patients with blunt injuries. However, to date, there has been no empirical evidence to confirm such impressions.
In addition to the clinical observation that patients with penetrating injuries (typically those with bullet wounds) experience higher rates of medical complications, there is an interest in studying the rate and type of medical complications of those with violence-related TBI in general because of the social and economic implications of such injuries for the rehabilitation process and society. Although patients with nonviolent injuries suffer significant setbacks personally and professionally, which also affect the economics of health care, violence is an ill that threatens the security and well-being of every social unit from the family to the country as a whole. Thus this study sought to assess the occurrence and type of medical complications that occur in violent injuries and to determine if there was a difference in the type and rate of occurrence of these complications between the different types of violent TBIs.
Despite the dearth of research on the medical complications specifically related to violent injuries, several recent reviews have highlighted the problem. 1–3 Also, Levy and colleagues 4 found that in penetrating craniocerebral injuries, infection around the bullet tract, wound dehiscence, cerebrospinal fluid leak, seizures, brain abscesses, and elevated intracranial pressures (ICP) were all fairly common complications. They also found that infection and elevation in ICP were predictive of Glasgow Outcome Scale (GOS) 7-determined outcome. 11 Kaufman, Makela, Lee and colleagues 8 found that hypoxia, anemia, hypotension and disseminated intravascular coagulation were associated with (though not significantly correlated with) worse outcome on the GOS. Aarabi 7 found that infectious complications were among the major prognostic indicators of the outcome (by GOS) of patients who sustained missile head wounds in the Iran-Iraq conflict. Ansari and Penezi 8 found that among Pakistani soldiers, cerebral vasospasm, seizures, and cardiopulmonary failure were the most frequent causes of death. Unfortunately, in their study no mention was made of outcome, except for mortality. Aldrich and colleagues 9 pointed to intracranial hypertension and hypotension as medical complications that resulted in especially poor outcomes as measured by GOS. Although medical complications were mentioned in these studies, they were not the principal focus. In the Levy and colleagues 4 study, for example, the effect of aggressive surgical management in cerebral gunshot wound patients with low Glasgow Coma Scale (GCS) 10 scores was the main issue. Kaufman and co-authors 6 focused on whether aggressive surgical management could lead to less mortality in patients with cerebral gunshot wounds. Aarabi 7 concentrated on surgical outcome amongst war-wounded cerebral gunshot wound patients. Ansara and Penezai 8 struggled with the question of triaging war-wounded cerebral gunshot wound patients and Aldrich and co-authors 9 dwelt on predictors of mortality in civilian cerebral gunshot wounds.
Suspecting that, true to clinical observations, there might be differences in the types and rates of medical complications depending on whether the patients' injuries were penetrating or blunt, we sought to confirm this impression through further literature review. No studies were found which distinguished between these two groups on the basis of the kinds of medical complications suffered.
Interestingly, Zafonte and colleagues 11 studied blunt and penetrating injury groups and their conclusions hinted indirectly at a possible relationship between medical complications, these two types of injuries, and functional outcome. This team of researchers found, for example, that patients with penetrating injury tend to have longer duration of posttraumatic amnesia (PTA), longer inpatient rehabilitation stays, higher acute care charges, higher rehabilitation charges, lower FIM score at rehabilitation discharge and at 1 year after injury, and higher disability rating scale (DRS) scores at rehabilitation discharge.
In an effort to identify reasons for these differences, we considered the idea that a higher incidence of medical complications, if such were shown to exist, in the penetrating group could partially explain this trend. It was hypothesized that a significantly higher incidence of medical complications occurs in the patients that survived penetrating injury as compared to those with blunt injury. The aims of this study, then, were to determine (1) whether there is a difference in the incidence and type of medical complications and comorbidities between the blunt and penetrating groups and (2) what factors (group membership, severity of injury, demographics) contribute to the frequency of these complications and comorbidities.