title: Impact of study oximeter masking algorithm on titration of oxygen therapy in the Canadian oxygen trial.
abstract: OBJECTIVE
  To compare oxygen saturations as displayed to caregivers on offset pulse oximeters in the 2 groups of the Canadian Oxygen Trial.
  
  
  METHODS
  In 5 double-blind randomized trials of oxygen saturation targeting, displayed saturations between 88% and 92% were offset by 3% above or below the true values but returned to true values below 84% and above 96%. During the transition, displayed values remained static at 96% in the lower and at 84% in the higher target group during a 3% change in true saturations. In contrast, displayed values changed rapidly from 88% to 84% in the lower and from 92% to 96% in the higher target group during a 1% change in true saturations. We plotted the distributions of median displayed saturations on days with >12 hours of supplemental oxygen in 1075 Canadian Oxygen Trial participants to reconstruct what caregivers observed at the bedside.
  
  
  RESULTS
  The oximeter masking algorithm was associated with an increase in both stability and instability of displayed saturations that occurred during the transition between offset and true displayed values at opposite ends of the 2 target ranges. Caregivers maintained saturations at lower displayed values in the higher than in the lower target group. This differential management reduced the separation between the median true saturations in the 2 groups by approximately 3.5%.
  
  
  CONCLUSIONS
  The design of the oximeter masking algorithm may have contributed to the smaller-than-expected separation between true saturations in the 2 study groups of recent saturation targeting trials in extremely preterm infants.
authors: Division of Neonatology, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. Electronic address: barbara.schmidt@uphs.upenn.edu.
authors: Barbara
authors: B
authors: Schmidt
authors: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada.
authors: Robin S
authors: RS
authors: Roberts
authors: Department of Pediatrics, Dalhousie University, Halifax, Canada.
authors: Robin K
authors: RK
authors: Whyte
authors: Department of Paediatrics, University of Toronto, Toronto, Canada.
authors: Elizabeth V
authors: EV
authors: Asztalos
authors: Department of Neonatology, Eberhard Karls University, Tuebingen, Germany.
authors: Christian
authors: C
authors: Poets
authors: Department of Pediatrics, University of Calgary, Calgary, Canada.
authors: Yacov
authors: Y
authors: Rabi
authors: Department of Pediatrics, University of British Columbia, Vancouver, Canada.
authors: Alfonso
authors: A
authors: Solimano
authors: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada.
authors: Harvey
authors: H
authors: Nelson
mesh_terms: D000465:Algorithms; D002138:Calibration; D002170:Canada; D017028:Caregivers; D004311:Double-Blind Method; D006801:Humans; D007223:Infant; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D008991:Monitoring, Physiologic / Q000379:methods; D010092:Oximetry / Q000379:methods*; D010100:Oxygen / Q000008:administration & dosage*; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D015203:Reproducibility of Results; D012984:Software; D013501:Surface-Active Agents / Q000627:therapeutic use
chemical_list: D013501:Surface-Active Agents; D010100:Oxygen