Routine self-measurement of blood ketones by people with diabetes is recommended for detection of Diabetic ketoacidosis (DKA) and euglycemic DKA (euDKA) related to use of SGLT2 inhibitors, though level of access to testing equipment may limit clinical implementation of monitoring recommendations. We researched feasibility and accuracy of a novel sensing technology that continuously measures glucose and ketones simultaneously in the subcutaneous space in a pig model.
We have evaluated a spectroscopy-based, implanted continuous glucose/ketone sensor in 4 Göttingen minipigs. Sensors were implanted in the subcutaneous abdominal tissue over the study period of 2 months. Ketosis in the non-diabetic animals was induced with i.v. beta-hydroxybutyrate, sequentially to oral and i.v. glucose challenges. Accuracy of the s.c. ketone and glucose sensor measurements have been compared to blood reference values measured with the Menarini Glucomen LX and a Biosen C-line EKF Diagnostics, respectively.
In 130 paired data points, overall Mean Absolute Difference (MAD) was below 0.2mM for s.c. ketone measurement compared to i.v. ketones. Accuracy for glucose measurements had an overall Mean Absolute Relative Difference (MARD) of 6.5% in 812 paired data points, compared to laboratory reference measurements. No adverse events related to surgical procedures or implant function were observed.
Dynamics of s.c. ketone levels closely correlate to blood ketone levels, similar to s.c. glucose compared to blood glucose. Measuring ketones and glucose continuously, simultaneously and in real-time with a spectroscopy-based, implantable sensor is feasible in healthy minipigs, both within and outside the physiological range. Further research will validate clinical value of the technology in humans.