title: Flushing of intravascular access devices (IVADs) - efficacy of pulsed and continuous infusions.
abstract: OBJECTIVE
  To compare, under controlled conditions similar to practical situations, the efficacy of pulsed and continuous infusion for flushing IVADs. For both of them different flow rates, flushing volumes, and times were tested.
  
  
  METHODS
  The PU catheter lumens were filled with a mixture of fibronectin and bovine albumin to simulate physiologic protein depot. Flushing was performed with normal saline. An adapted pump controlled the flow rates. Efficacy was measured by the amount of albumin recovered from the lumen of the tested devices. Flow rate, volumes, and times tested were based upon values reported and/or measured in nursing practices. We compared: (A) single 10 mL bolus and 6 flushing times, (B) continuous infusion of 500 mL in 24 hours, (C) 10 successive boluses 1 mL flushed in 0.5 s each and 6 different time intervals between each bolus. Statistics were performed using the Mann and Whitney U test.
  
  
  RESULTS
  In group A, the maximum percentage of recovered protein (79.1% was achieved with the 10 mL bolus flushed in 2.5. In group B, 77% of protein was recovered at 24h. In group C: maximum efficacy (90 +/- 3%) was obtained when the time interval between 2 boluses was 0.4 s.
  
  
  CONCLUSIONS
  We conclude that hydrodynamics has a determinant effect on the efficacy and that the adjunction of an intermittent component in the flow increases it. Flow type and the time interval between 2 boluses are the 2 critical variables.
authors: MSC-UMR 7057, Université Paris Diderot, Paris, France. gerard.guiffant@univ-paris-diderot.fr
authors: Gérard
authors: G
authors: Guiffant
authors: Jean Jacques
authors: JJ
authors: Durussel
authors: Jacques
authors: J
authors: Merckx
authors: Patrice
authors: P
authors: Flaud
authors: Jean Pierre
authors: JP
authors: Vigier
authors: Patrice
authors: P
authors: Mousset
mesh_terms: D002405:Catheterization, Central Venous / Q000009:adverse effects / Q000295:instrumentation*; D002406:Catheterization, Peripheral / Q000009:adverse effects / Q000295:instrumentation*; D002408:Catheters, Indwelling; D004867:Equipment Design; D004868:Equipment Failure; D005353:Fibronectins / Q000008:administration & dosage; D057446:Hydrodynamics; D007260:Infusion Pumps; D007263:Infusions, Parenteral; D011673:Pulsatile Flow; D012212:Rheology; D012710:Serum Albumin, Bovine / Q000008:administration & dosage; D012965:Sodium Chloride / Q000008:administration & dosage*; D013997:Time Factors
chemical_list: D005353:Fibronectins; D012710:Serum Albumin, Bovine; D012965:Sodium Chloride