Impact of infusion line compliance on syringe pump performance

To determine the impact of infusion line compliance on the time to occlusion alarm (occlusion time) and the size of the subsequent occlusion release bolus, we studied three different infusion lines in combination with a 50-ml and 10-ml syringe. The mean occlusion time of the 50-ml syringe amounted to 20.3 +/- 0.28 min and increased to 26.2 +/- 0.19 min with the infusion with the infusion line yeielding the largest compliance (P<0.0001). The mean occlusion time of the 10-ml syringe was 2.5 +/- 0.75 min and showed a 2.7-fold variation with the three infusion lines (2.6+/-0.08, 5.6 +/- 0.28 and 6.9 +/- 0.35 min, respectively; P<0.0001). Occlusion times correlated strongly to be calculated estimated compliance of the syringe-infusion line assembly (Pearson's r=0.998, P<0.0001). Infusion line compliance has an important impact on time to occlusion, particularly when using small, low compliant infusion pump syringes.