|89th Annual Meeting Abstracts
Craniofacial Fracture Patterns Predictive of Blunt Internal Carotid Artery Injury: Analysis of 4,398 Patients with 54 Concomitant Blunt Internal Carotid Artery Injuries
Gerhard S. Mundinger, M.D1, Amir H. Dorafshar, MD1, Suhail K. Mithani, MD1, Helen G. Hui-Chou, MD1, Ian Smith, MD2, Paul N. Manson, MD2, Eduardo D. Rodriguez, M1.
1Johns Hopkins Hospital/R Adms Cowley Shock Trauma Center, Baltimore, MD, USA, 2Johns Hopkins Hospital, Baltimore, MD, USA.
The association between craniofacial fractures and blunt internal carotid artery (BICA) injury is poorly understood. This study was designed to determine whether specific facial fracture patterns are associated with increased risk for BICA injury.
A retrospective review of 4,398 consecutive patients diagnosed with blunt maxillofacial fractures at a dedicated urban trauma center from 1998 to 2006 was conducted. Radiographic images for all patients were reviewed to confirm fractures. Fractures were grouped by dividing the craniomaxillofacial skeleton into upper, middle, and lower thirds. Identified internal carotid artery injuries were confirmed and graded using the Biffl system. As all patients with facial fractures meeting inclusion criteria were captured during this time period, relative risks (RR) for BICA injury were calculated by fracture pattern using Fisher’s Exact Test. All results presented here were statistically significant (p-value <0.05, two-tailed).
70 BICA injuries were identified in 54 patients (1.2%). Admission GCS was negatively correlated with ISS and death (Adjusted R2 0.20 and 0.15, respectively). Both admission ISS and carotid injury grade correlated positively with mortality (adjusted R2= 0.13 and 0.24, respectively). The RR of death increased by 3.5 with every increase in carotid injury grade. For every additional facial fracture irrespective of fracture location, the RR of BICA injury increased by 1.31. Patients with basilar skull fractures in combination with any fracture pattern were at increased risk for BICA injury when compared to patients without concomitant basilar fractures (RR= 9.0, actual incidence 6.8 % vs 0.7%). Although patients with either bilateral or unilateral midface fractures had lower RR for BICA injury when compared to patients with other fracture patterns (RR=0.56, actual incidence 0.6% vs 2.2%), patients with isolated bilateral midface fractures were at increased risk for BICA injury (RR=2.7, actual incidence 3.4% vs. 1.1%). Risk of BICA injury was higher in patients with bilateral midface fractures when compared to unilateral midface fractures (RR=4.9, actual incidence 3.3% vs 0.3%). Furthermore, patients with bilateral midface fractures in combination with basilar skull fractures were at markedly increased risk for BICA injury when compared to all other fracture patterns (RR= 20.1, actual incidence 20% vs 1.0%). Moreover, patients with bilateral midface fractures alone were at greater risk of death if they happened to have associated BICA injury (RR of death 4.97, actual incidence 10.8% vs 2.2%).
In a large retrospective series of blunt trauma patients with facial fractures, patients with bilateral midface fractures in combination with basilar skull fractures were at highest RR for concomitant BICA injury. This is likely due to force transmission to the skullbase. Patients with bilateral midface fractures were at high RR of death if a concomitant BICA injury was present. Suspicion for BICA injury in these patients may improve diagnosis and enable prompt therapeutic intervention.