title: Measurement of systolic blood pressure using pulse oximetry during helicopter flight.
abstract: OBJECTIVE
  Monitoring of vital signs in critically ill patients during helicopter flight is difficult because of the noise and vibrations of the aircraft. We evaluated the use of a pulse oximeter to measure systolic BP intraflight.
  
  
  METHODS
  Systolic BP measured by pulse oximetry was compared with systolic BP measured by the direct intra-arterial and the arterial occlusion methods intraflight. Systolic BP by pulse oximetry was measured by observing the return of the plethysmographic waveform of the pulse oximeter as the BP cuff ipsilateral to the pulse oximeter probe was slowly deflated. Arterial occlusion pressure was measured by observing the return of the intraarterial waveform as the BP cuff ipsilateral to the arterial cannula was slowly deflated.
  
  
  METHODS
  The study was performed during patient transport, intraflight.
  
  
  METHODS
  Ten critically ill patients were studied.
  
  
  METHODS
  None
  
  
  RESULTS
  Seventy-three sets of measurements were recorded. The best correlation (r2 = .99) was found between pulse oximetry and the arterial occlusion method. The indirect methods correlated better with each other than with direct intraarterial measurements. The noise and the vibrations of the helicopter did not significantly interfere with the operation of the pulse oximeter.
  
  
  CONCLUSIONS
  We conclude that a pulse oximeter that displays a plethysmographic waveform can accurately measure systolic BP intraflight.
authors.affiliation: Department of Anesthesiology, University of Texas Medical Branch, Shriners Burns Institute, Galveston 77550.
authors.forename: P O
authors.initials: PO
authors.lastname: Talke
mesh_terms: D000328:Adult; D000401:Aircraft; D001795:Blood Pressure Determination / Q000379:methods*; D003422:Critical Care; D005069:Evaluation Studies as Topic; D006801:Humans; D008875:Middle Aged; D010092:Oximetry / Q000592:standards*; D010991:Plethysmography; D015203:Reproducibility of Results; D014187:Transportation of Patients