Abstracts

Rationale: Sudden Unexpected Death in Epilepsy (SUDEP) is the leading cause of death in epilepsy children and otherwise healthy adult epilepsy patients. About 70% of SUDEP occurs during sleep, and nearly 90% are found in the prone (face-down) position. SUDEP can likely be prevented by simple interventions such as turning and stimulating. Such intervention must be performed quickly within a 3-minute window prior to death. There are currently no products that detect the prone position or have the ability to physically reposition a patient into a recovery position.


Methods: We address this critical unmet medical need with a smart mattress, the Korus, consisting of an array of inflatable cells. We developed 1) a sensor system to rapidly detect body change with high accuracy; 2) an advanced expandable cell that is capable of generating the required lift at sufficient velocity to reposition a patient from the prone to the recovery (sideways) position.


Results: Each inflatable cell that comprises the Korus has the capacity to generate lift to 1000 lb/cell at a rate of 2 inches per second. The embedded sensor array can detect body position change within 5 seconds. A total of 10 normative control subjects were tested. Repositioning from a prone to recovery (sideways) position while manually controlling the cells was successful in 100% of attempts with an average time of 21.75 sec. Body position detection resulted in an accuracy in detecting the prone position of 96.8% and an overall accuracy of detecting the correct body position (supine, prone, left, right, Figure 1) of 92.4% (Figure 2). In long-term studies including sleep, Korus detected the correct position during 97.3% of the time during the recording. False body position change rate was 2.3 events/hour. There were no incorrect position detections when subjects switched into the prone position.


Conclusions: This study demonstrates the feasibility of developing a smart mattress to detect the prone position and rapidly repositioning subjects into a recovery position. Future development include the development of a control system to automate repositioning based on sensor data. The completion of this device, when paired with a seizure detection device, has the potential to lower the risk of SUDEP by >50%.

Funding: NIH SBIR R43NS120394