title: Optimizing care of ventilated infants by improving weighing accuracy on incubator scales.
abstract: OBJECTIVE
  To determine the accuracy of weighing ventilated infants on incubator scales and whether the accuracy can be improved by the addition of a ventilator tube compensator (VTC) device to counterbalance the force exerted by the ventilator tubing.
  
  
  METHODS
  Body weights on integral incubator scales were compared in ventilated infants (with and without a VTC), with body weights on standalone electronic scales (true weight). Individual and series of trend weights were obtained on the infants. The method of Bland and Altman was used to assess the introduced bias.
  
  
  RESULTS
  The study included 60 ventilated infants; 66% of them weighed <1000 g. A total of 102 paired-weight datasets for 30 infants undergoing conventional ventilation and 30 undergoing high frequency oscillator ventilation (HFOV) supported by a SensorMedics oscillator, (with and without a VTC) were obtained. The mean differences and (95% CI for the bias) between the integral and true scale weighing methods was 60.8 g (49.1 g to 72.5 g) without and -2.8 g (-8.9 g to 3.3 g) with a VTC in HFOV infants; 41.0 g (32.1 g to 50.0 g) without and -5.1 g (-9.3 g to -0.8 g) with a VTC for conventionally ventilated infants. Differences of greater than 2% were considered clinically relevant and occurred in 93.8% without and 20.8% with a VTC in HFOV infants and 81.5% without and 27.8% with VTC in conventionally ventilated infants.
  
  
  CONCLUSIONS
  The use of the VTC device represents a substantial improvement on the current practice for weighing ventilated infants, particularly in the extreme preterm infants where an over- or underestimated weight can have important clinical implications for treatment. A large-scale clinical trial to validate these findings is needed.
authors.affiliation: Neonatal Intensive Care Unit, Royal Bolton Hospital, Bolton, UK.
authors.forename: Ula
authors.initials: U
authors.lastname: El-Kafrawy
authors.affiliation: Department of Medical Physics, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: R J
authors.initials: RJ
authors.lastname: Taylor
mesh_terms: D000886:Anthropometry / Q000295:instrumentation / Q000379:methods*; D001835:Body Weight; D005260:Female; D006612:High-Frequency Ventilation / Q000295:instrumentation*; D006801:Humans; D007186:Incubators, Infant; D052577:Infant, Extremely Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D010865:Pilot Projects; D012121:Respiration, Artificial / Q000295:instrumentation; D012127:Respiratory Distress Syndrome, Newborn / Q000628:therapy*
keywords: Neonatology; incubator scales; intensive care; ventilated infants; weight measurement