title: In-line filter included into the syringe infusion pump assembly reduces flow irregularities.
abstract: OBJECTIVE
  To evaluate whether an in-line filter inserted in the syringe pump infusion line assembly influences start-up times and flow irregularities during vertical pump displacement at low infusion rates.
  
  
  METHODS
  Fluid delivery after syringe pump start-up and after vertical displacement of the syringe pump by -50 cm was determined gravimetrically at flow rates of 0.5, 1.0 and 2.0 ml h(-1). Measurements were repeated for each flow rate four times with two different syringe pumps with and without an in-line filter incorporated. Data are shown as median and range.
  
  
  RESULTS
  Start-up times were reduced by an in-line filter at 0.5 ml h(-1) flow rate from 355.5 s (0-660) to 115 s (0-320), whereas the effect was attenuated at higher flow rates. Pooling of fluid into the infusion system after lowering the infusion syringe pump was halved in all flow rates tested. Amount of infusion bolus after elevating the syringe pump by 50 cm was not affected by an in-line filter.
  
  
  CONCLUSIONS
  In the evaluated model in-line filters help to reduce flow irregularities and delay in drug delivery of syringe pumps at low flow rates and represent an option to optimize continuous administration of highly concentrated short-acting drugs at very small infusion rates.
authors.affiliation: Department of Neonatology and Intensive Care, University Children's Hospital Zurich, Steinwiesstr 75, 8032 Zurich, Switzerland. barbara.brotschi@kispi.uzh.ch
authors.forename: B
authors.initials: B
authors.lastname: Brotschi
authors.forename: B
authors.initials: B
authors.lastname: Grass
authors.forename: M
authors.initials: M
authors.lastname: Weiss
authors.forename: C
authors.initials: C
authors.lastname: Doell
authors.forename: V
authors.initials: V
authors.lastname: Bernet
mesh_terms: D016503:Drug Delivery Systems / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D006874:Hydrostatic Pressure; D007260:Infusion Pumps; D010865:Pilot Projects; D013594:Syringes