A percutaneous device to study glucose kinetics in subcutaneous tissue fluid

In the current study subcutaneous glucose kinetics were investigated in tis sue fluid collected with a percutaneous device (PD), PDs containing a subcu taneous tissue chamber were implanted subcutaneously in New Zealand white r abbits. Sintered titanium fiber mesh sheets were used for subcutaneous anch orage of the PD, The bottom of the subcutaneous tissue chamber was either c overed with a titanium fiber mesh sheet, a cellulose acetate membrane, or l eft uncovered. Subcutaneous glucose kinetics were determined after injectio n of octreotide and glucagon, The tissue reaction to the implants was evalu ated histologically, No dynamic relationship was observed between glycaemia and subcutaneous tissue fluid glucose for all membrane covered devices, Hi stological evaluation showed that the presence of a sere ma cavity in com b i nation with obstruction of the membrane prevented adjustment of the subcu taneous glucose concentration in response to changesing lycaemia, In the un covered devices, on the other hand, changes in glycaemia were reflected in subcutaneous tissue fluid. Our results prove that it is possible to measure changes in the glucose concentration in subcutaneous tissue fluid collecte d with a percutaneous device. Therefore, we conclude that a percutaneous de vice has an application as model to study the in vivo performance of implan table glucose sensors. The use of porous membranes in such devices has to b e avoided. (C) 2000 Kluwer Academic Publishers.