NAPLES, FLA. – A regional trauma system decreased hospital mortality for traumatic brain injury patients by 21% overall and by 26% for severe brain injuries, according to a partially retrospective study.
"Regionalization represents an additional step in attempting to improve outcomes for trauma patients. It can be defined as a tiered, integrated system that attempts to get the right patient to the right place at the right time," Dr. Michael L. Kelly said at the annual meeting of the Eastern Association for the Surgery of Trauma.
Dr. Michael L. Kelly
A few American studies and several more outside the United States have shown that regionalization decreases mortality in the general trauma population, but similar studies in traumatic brain injury (TBI) patients are scarce.
The Northern Ohio Trauma System (NOTS) was organized in 2010 and includes a transfer line to the Level I trauma center, a nontrauma hospital transfer protocol, a pilot scene triage protocol for emergency medical services, as well as the creation of a trauma-specific ICU in the level I center, explained Dr. Kelly, a sixth-year neurosurgery resident at the Cleveland Clinic, Ohio. The network includes the Level I MetroHealth Medical Center trauma center, two Level II trauma centers, and 12 nontrauma hospitals.
The three-tiered system mandates that TBI patients with a Glasgow Coma Scale (GCS) score of less than 12 and a traumatic mechanism, any penetrating head injury, or any open/depressed skull fracture, be sent to the Level I trauma center if they can be transferred within 15 minutes.
Patients with a GCS of 12-14 and a penetrating mechanism can be transferred to any trauma center, while those with lesser head injuries can remain at their hospital, unless their condition worsens.
For the study, Dr. Kelly and his coauthors analyzed data from 2008 through 2012 for 11,220 patients more than 14 years old with a TBI in the NOTS database, which was populated prospectively beginning in mid-2010.
Level I admissions increased significantly after NOTS by 10% for all TBIs (36% vs. 46%) and by 15% for severe TBIs with a head Abbreviated Injury Scale (AIS) score of 3 or more, he said. The percentage of patients who underwent transfers between NOTS institutions also increased significantly by 7% (7% vs. 14%) and 11% (10% vs. 21%), respectively.
Hospital mortality declined from 6.2% to 4.9% post-NOTS for all TBI patients (P = .005) and from 19% to 14% for the subset with severe TBI (P less than .0001). Mortality for trauma patients in general in Ohio has consistently hovered at 4% to 5% for the last decade, despite efforts to improve outcomes, including a 2002 law requiring the transfer of trauma patients to a validated trauma center, Dr. Kelly said.
In the post-NOTS period, craniotomies increased significantly for all TBIs (2% vs. 3%; P = .003) and for severe TBIs (6% vs. 8%; P = .02). The use of any neurosurgical procedure and hospital length of stay, however, remained constant for both groups in both time periods.
At baseline, the 6,713 post-NOTS patients were significantly older than the 4,507 pre-NOTS patients (55 years vs. 52 years) and less likely to be male (63% vs. 66%) or black (23% vs. 34%). GCS scores were similar (15 for both), as were Injury Severity Scores (14 for both) and the percentage of patients with a head AIS of 3 or more (34% post- vs. 32% pre-).
Multivariate regression analysis showed that the NOTS time period was an independent predictor of survival for all TBIs, with an odds ratio of 0.76, representing a 24% mortality reduction, and odds ratio of 0.72 for severe TBIs, representing a 28% mortality reduction.
Dr. Deborah Stein
"Of some importance, the multivariate model actually strengthened the effect of NOTS on mortality in our patient population," Dr. Kelly said.
Invited discussant Deborah Stein, medical director of neurotrauma critical care at the R Adams Cowley Shock Trauma Center at the University of Maryland Medical Center in Baltimore, described the study as an important contribution to the growing body of literature demonstrating that regionalization of care is associated with improved outcomes.
Dr. Stein went on to congratulate the NOTS members for participating in what was, at times, likely a contentious and difficult process: to bring a diverse group of hospitals to consensus about the best way to care for injured patients.
"Effecting change is difficult enough in a single division, department, or hospital," she remarked.
Following the formal presentation, audience members questioned whether the change in mortality was accomplished by simply shifting patients to nursing homes to die or whether it reflects a more aggressive surgical approach to TBI or improved critical care.