Insulin pumps require an alarm feature to notify the user about occlusions in the tubing or the catheter tip to ensure adequate insulin supply. There is no explicit demand regarding a maximal delay time between occlusion and alarm. In this study, occlusion detection time of two new patch pumps was evaluated and compared to previous data from an already established patch pump.
Soft cannulas of the Accu-Chek® Solo micropump [ACS] and the A6 TouchCare® pump [A6] were occluded with a clamp and time until an occlusion alarm occurred was stopped using two different basal rates (1 U/h and 0.1 U/h). Each experiment was repeated 9 times.
At the 1 U/h basal rate, the mean occlusion detection time was 02:57 (hh:mm) for ACS and 07:26 for A6. Using the smaller basal rate of 0.1 U/h, an alarm occurred after 35:11 for ACS. For A6 no occlusion alarm occurred in any of the 9 repetitions until the end of the pump run time.
Occlusion detection was faster in ACS than in A6; however, for the low basal rate it was markedly delayed in both pumps. This was also observed for the previously tested Omnipod. At the larger basal rate, ACS provided the alarm earlier than the Omnipod.