title: Bubble formation occurs in insulin pumps in response to changes in ambient temperature and atmospheric pressure but not as a result of vibration.
abstract: BACKGROUND
  Bubble formation in insulin pump giving sets is a common problem. We studied change in temperature, change in atmospheric pressure, and vibration as potential mechanisms of bubble formation.
  
  
  METHODS
  5 Animas 2020 pumps with 2 mL cartridges and Inset II infusion systems, 5 Medtronic Paradigm pumps with 1.8 mL cartridge and Quickset and 3 Roche Accu-chek pumps with 3.15 mL cartridges were used. Temperature study: insulin pumps were exposed to a temperature change from 4°C to 37°C. Pressure study: insulin pumps were taken to an altitude of 300 m. Vibration study: insulin pumps were vigorously shaken. All were observed for bubble formation.
  
  
  RESULTS
  Bubble formation was observed with changes in temperature and atmospheric pressure. Bubble formation did not occur with vibration.
  
  
  CONCLUSIONS
  Changes in insulin temperature and atmospheric pressure are common and may result in bubble formation. Vibration may distribute bubbles but does not cause bubble formation.
authors.affiliation: John Hunter Children's Hospital , Newcastle, New South Wales , Australia ; Mothers and Babies Research Group , Hunter Medical Research Institute , Newcastle, New South Wales , Australia ; University of Newcastle , Newcastle, New South Wales , Australia.
authors.forename: Prudence E
authors.initials: PE
authors.lastname: Lopez
authors.affiliation: John Hunter Children's Hospital , Newcastle, New South Wales , Australia ; Mothers and Babies Research Group , Hunter Medical Research Institute , Newcastle, New South Wales , Australia ; University of Newcastle , Newcastle, New South Wales , Australia.
authors.forename: Bruce R
authors.initials: BR
authors.lastname: King
authors.affiliation: Gippsland Paediatric Diabetes Unit, Sale, Victoria , Australia.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Goss
authors.affiliation: John Hunter Hospital , Newcastle, New South Wales , Australia.
authors.forename: Ganesh
authors.initials: G
authors.lastname: Chockalingam
keywords: Insulin Pump Therapy; Parenting Stress; Pediatric Diabetes