| Specification | Description | Metric |
| Outcome Warning Level | An algorithm designed to calculate the prediction score for transplant success and use that score to provide surgeons with a warning level. | Prediction score is calculated based on donor factors similar to the pancreas donor risk index (PDRI). The algorithm will take into account donor age, BMI, hypertension/diabetes history, Hep. C history, and whether the donor is African American. This value will be used to assign a risk level to the transplant patient. If the predictor indicates a high risk for organ failure, the interface for the sensor will output the readings with a higher warning level. |
| Tissue Temperature | A function of the sensor which will measure the temperature of the pancreas tissue as a proxy for inflammation, which in itself is a measure of rejection. | The sensor will monitor the temperature of the pancreas tissue and return that value continuously. A warning will be sent to notify the surgeons if the value reaches above 100°F [11]. |
| Tissue Pressure | A function of the sensor which will measure the osmotic pressure of the pancreas tissue as an indicator of tissue swelling which could be caused by inflammation and rejection. | The sensor implanted in the pancreas tissue will monitor the interstitial fluid pressure and return that value to provide a proxy for the level of edema in the tissue. A warning will be sent to notify the surgeons if the pressure reaches above +6 mmHg [1]. |
| Blood Flow Rate | A function of the sensor to measure the blood flow rate in the pancreas tissue as an indicator of pancreas function. | The sensor will monitor the blood flow rate in the pancreas tissue and return that value continuously. A warning will be sent to notify the surgeons if the value reaches above or below the range, 4.1 +/- 1.2 ml/min per gram [5]. |
| Tissue Oxygenation | A function of the sensor to measure the oxygenation level of the pancreas tissue as an indicator of pancreas function | The implanted sensor will monitor the oxygenation level, in terms of oxygen partial pressure, in the cortical later pancreas tissue and return that value continuously. A warning will be sent to notify the surgeons if the value reaches below 58 mmHg [13]. |
| Battery Capabilities | A characteristic of the sensor that will allow long duration, stability, and high efficiency once implanted into pancreas tissue. | Based on Dr. MacEwan’s previous device, the battery life could be adjusted based on the lithium battery chosen. This allowed a battery life of days or weeks. For a pancreas transplant, patients are monitored closely for three weeks to two months, which would require a minimum battery life of three weeks. |
| Long-term Implant Capabilities | The sensor should be able to remain implanted in the pancreas tissue for a long period of time after transplant surgery in order to maintain long-term and short-term monitoring capabilities. | The sensor should be able to maintain function and monitoring for 1 month post transplantation. After that period of time, the device could be removed via a probe, or be biodegraded by the body. For verification and validation, a minimum of 2 hours to accommodate utilizing a live, anesthetized rat model. |
| Wireless Capabilities | The sensor should be able to transmit data from the patient to the transplant surgeon team at the hospital. | The sensor should be able to transmit information to an external source within a 5 mile radius of the patient, which can then be transmitted from the external device (iPad) to the hospital network. |