In my previous post, I reviewed the Brain Injury Guideline criteria (BIG) that were published in 2014, and cited some early papers promoting its use for simplifying neurotrauma care. These criteria allowed trauma professionals to use our neurosurgical colleagues’ services more sensibly.
As a reminder, these are the original BIG criteria:
Some revisions were proposed in 2020 to improve patient safety and reproducibility further. Here are the revised criteria:
So, what are the differences?
- The “loss of consciousness” was changed to a more objective assessment, the GCS
- Intoxication is defined as a blood alcohol concentration > 80 mg/dL
- Aspirin and NSAIDs are not considered antiplatelet agents
- Epidural hematoma (EDH) is no longer sized; any epidural moves the patient to mBIG 3
- Multiple intraparenchymal hemorrhages (IPH) move the patient to mBIG 3
- Subarachnoid hemorrhage is more objectively classified
The mBIG criteria were tested in a multi-institutional review comparing the original criteria with the modified criteria. BIG 3 patients were excluded, since these patients required admission and neurosurgical consultation, which is maximal therapy. All patients underwent repeat CT scans to monitor for progression of the injury.
Here are the factoids:
- A total of 269 patients were included; 98 were BIG 1 and 171 were BIG 2
- In both BIG 1 and BIG 2 cohorts, CT progression was seen in about 11% of patients. These patients tended to have more severe injuries overall and were more likely to have EDH or IPH.
- Two BIG 2 patients decompensated and required neurosurgical intervention; both had EDH
These findings prompted the changes that are now part of the mBIG score. Here is the complete algorithm based on the mBIG criteria (click to see full-size):
A larger validation study was published in 2022 by the same authors, following the addition of 496 patients from the same three trauma centers. The total number of patients included in the study was 496.
More factoids:
- There were now a total of 223 mBIG 1 patients and 273 mBIG2
- The number of CT scans and neurosurgery consults was significantly decreased
- Hospital length of stay was also significantly decreased
Bottom line: The mBIG criteria perform better and are at least as safe as the initial BIG criteria. The mBIG criteria are more objective, making it easier to stratify patients accurately.
The mBIG criteria should be adopted by any center seeking a consistent and validated process for stratifying patients for observation, admission, or neurosurgical consultation following head trauma. This will conserve resources and allow our neurosurgical colleagues to focus on the patients who truly need them.
References:
- Multicenter assessment of the Brain Injury Guidelines and a proposal of guideline modifications. Trauma Surgery & Acute Care Open, 5(1), e000483.
- A multicenter validation of the modified brain injury guidelines: Are they safe and effective?. Journal of Trauma and Acute Care Surgery 93(1):p 106-112, July 2022.