Each year in the United States, 1.5 million people sustain a traumatic brain injury (TBI), and an estimated 5.3 million individuals endure chronic disability as a result of their injuries. One such disability is secondary neurological decline (ND), a progressive onset of neurological and cognitive deficits that can occur as a result of TBI. In the hours following resuscitation after moderate to severe TBI, clinicians typically try to identify patients who are at high risk for developing ND. Timely intervention has the potential to minimize the negative effects of ND, so early risk detection is critical for improving patient outcomes after TBI.
A recent study in Maryland investigated the relationship between continuous vital sign monitoring and accurate prediction of ND in individuals with TBI. Researchers wanted to know if constant monitoring in the first hour after injury is an effective way to assess an individual’s risk of developing ND, thereby allowing clinicians to apply medical intervention. They selected vital sign measures for analysis: the first was the electrocardiogram (ECG), which measures heartbeat, and the second was the photoplethysmogram (PPG), which can estimate blood flow and blood volume beneath the skin. Both the ECG and the PPG are common methods for monitoring cardiovascular and respiratory health in patients who have sustained serious head injuries. After analyzing hospital records (which included these vital sign measurements) from 191 patients who were admitted to the University of Maryland Medical Center with moderate to severe TBI, the researchers found that:
- Individuals who did develop ND within 48 hours of their injuries had longer hospital stays and higher mortality rates, suggesting that ND is strongly associated with poor outcomes.
- ECG and PPG analyses within the first 15 minutes of resuscitation predicted the development of ND more accurately than a clinical examination alone.
- Prediction of ND was most accurate when continuous vital sign measurement was used in combination with clinical assessment.
Continuous vital sign monitoring in the first hour after TBI is a promising tool for predicting development of ND. Early detection allows clinicians to develop targeted interventions that can mitigate the negative outcomes associated with ND, improving an individual’s chances of survival and recovery after TBI. Monitoring ECG and PPG measurements is a valuable method for enhancing clinical risk assessment in the immediate post-injury period.
Melinosky C, Yang S, Hu P, et al. Continuous vital sign analysis to predict secondary neurological decline after traumatic brain injury. Frontiers in Neurology. (September 2018).