title: Electrical impedance tomography for verification of correct endotracheal tube placement in paediatric patients: a feasibility study.
abstract: BACKGROUND
  Endotracheal tubes (ETTs) are frequently used in paediatric anaesthesia. Correct placement is crucial. The aim of this study was to evaluate electrical impedance tomography (EIT) for guiding and confirmation of paediatric ETT placement. In a retrospective analysis of stored EIT data, distribution of ventilation between left and right lung was used to verify correct paediatric ETT placement.
  
  
  METHODS
  Left and right lung ventilation was studied by EIT in 18 paediatric patients (median age: 53 months) requiring anaesthesia and endotracheal intubation. EIT was recorded before induction of anaesthesia, during mask ventilation, during ETT placement (including deliberate mainstem intubation), and after ETT repositioning according to the formula: ETT intubation depth (cm) = 3× ETT internal diameter (mm) or the mainstem intubation method (withdrawing the ETT 2 cm). Final ETT position was confirmed by fluoroscopy.
  
  
  RESULTS
  Following deliberate mainstem intubation, distribution of ventilation to the right lung was unequivocally demonstrated by EIT. Homogeneous distribution of ventilation between left and right lung monitored with EIT correlated in each patient with correct endotracheal ETT placement. The distribution of left and right lung ventilation differed significantly (P < 0.05) between the initial two-lung ventilation and subsequent right one-lung ventilation, and between right one-lung and subsequent two-lung ventilation according to auscultation and the final ETT position, respectively. In one patient, ETT was misplaced within the oesophagus which was also obvious from the EIT record.
  
  
  CONCLUSIONS
  This study demonstrates that EIT enables non-invasive recognition of correct ETT placement. Homogeneous right-left-lung ventilation is an indicator for correct ETT placement.
authors.affiliation: Department of Occupational Medicine, University Medical Center Freiburg, Freiburg, Germany. daniel.steinmann@uniklinik-freiburg.de
authors.forename: D
authors.initials: D
authors.lastname: Steinmann
authors.forename: M
authors.initials: M
authors.lastname: Engehausen
authors.forename: B
authors.initials: B
authors.lastname: Stiller
authors.forename: J
authors.initials: J
authors.lastname: Guttmann
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D017097:Electric Impedance; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007223:Infant; D007442:Intubation, Intratracheal / Q000379:methods; D008297:Male; D012123:Pulmonary Ventilation; D012189:Retrospective Studies; D014054:Tomography / Q000379:methods*