title: In vitro measurement of flow rate variability in neonatal IV therapy with and without the use of check valves.
abstract: BACKGROUND
  In multi-infusion IV therapy, the actual volume delivered to the neonate can vary over time. To reduce flow rate variability, check valves can be used. A check valve allows flow through the valve in only one direction.
  
  
  OBJECTIVE
  To evaluate flow rate variability in a low flow dual-infusion setup with and without check valves.
  
  
  METHODS
  The effect of changing the height of and adding syringes to the IV-administration set was tested with and without check valves in an in vitro dual-infusion setup with in-line flow meters. The pre-programmed flow rates were 2.5 and 0.1 ml/h.
  
  
  RESULTS
  Twenty-four tests of 90 minutes were performed. Time to reach 75% of the pre-programmed 0.1 ml/h flow rate was >20 minutes. The highest total delivered volume during a test was (mean ± SD) 56 ± 8% of the expected delivery for tests without check valves, and diminished to 12 ± 24% of the expected delivery for check valves with a higher opening pressure.
  
  
  CONCLUSIONS
  The actual flows and the total delivered volume in low flow dual-infusion setups are less than expected on the pre-programmed flow-rate. These findings emphasize the need for the development of more accurate delivery systems for drugs and fluids in neonatology. Caregivers should be aware of these findings, and optimise the delivery of IV substances by making use of check valves with low opening pressures and by minimising compliance and volume of the IV-administration set. Furthermore, changes in the relative height between pumps and catheter tip should be minimized.
authors.affiliation: Department of BioMechanical Engineering, Faculty of Mechanical, Maritime & Materials Engineering, Delft University of Technology, Delft, The Netherlands Department of Neonatology, Erasmus MC, Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: A C
authors.initials: AC
authors.lastname: van der Eijk
authors.affiliation: Department of Medical Technology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: van der Plas
authors.affiliation: Department of Medical Technology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: C J N M
authors.initials: CJ
authors.lastname: van der Palen
authors.affiliation: Department of BioMechanical Engineering, Faculty of Mechanical, Maritime & Materials Engineering, Delft University of Technology, Delft, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Dankelman
authors.affiliation: Patient Directorate Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: B J
authors.initials: BJ
authors.lastname: Smit
mesh_terms: D000704:Analysis of Variance; D016503:Drug Delivery Systems / Q000295:instrumentation*; D004867:Equipment Design / Q000295:instrumentation*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007231:Infant, Newborn; D007260:Infusion Pumps; D007262:Infusions, Intravenous / Q000295:instrumentation*; D015931:Intensive Care, Neonatal; D008297:Male; D013594:Syringes
keywords: IV therapy; Neonatology; anti-siphon; check valve; multi-infusion