title: Is noninvasive hemodynamic monitoring appropriate for the elderly critically injured patient?
abstract: BACKGROUND
  Noninvasive hemodynamic monitoring in critically ill patients using bioimpedance technology has been shown to be a reliable alternative to invasive thermodilution techniques. However, there have been some concerns that the bioimpedance method may be unreliable in elderly patients with an atherosclerotic and rigid thoracic aorta. The purpose of the present study was to evaluate the effect of age on the reliability of noninvasive bioimpedance technology in measuring cardiac index.
  
  
  METHODS
  This is a retrospective analysis of prospectively collected data in critically injured patients admitted to the surgical intensive care unit. All patients had simultaneous measurement using thermodilution cardiac index (TDCI) and bioimpedance cardiac index (BICI). The population was divided into three age groups (<55 years, 55-70 years, and >70 years). The correlation between TDCI and BICI was calculated for each age group.
  
  
  RESULTS
  There were 1,138 simultaneous measurements of TDCI and BICI in 285 patients. The BICI correlated well with TDCI in all three age groups (r = 0.82 for group <55 years, r = 0.87 for group 55-70 years, and r = 0.80 for group >70 years).
  
  
  CONCLUSIONS
  Noninvasive cardiac index monitoring in elderly patients is reliable and correlates well with standard thermodilution techniques.
authors.affiliation: Department of Surgery, Division of Trauma and Critical Care, University of Southern California, Los Angeles, California 90033, USA. carlosbr@usc.edu
authors.forename: Carlos V R
authors.initials: CV
authors.lastname: Brown
authors.forename: William C
authors.initials: WC
authors.lastname: Shoemaker
authors.forename: Charles C J
authors.initials: CC
authors.lastname: Wo
authors.forename: Linda
authors.initials: L
authors.lastname: Chan
authors.forename: Demetrios
authors.initials: D
authors.lastname: Demetriades
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002307:Cardiography, Impedance; D016638:Critical Illness; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D012044:Regression Analysis; D012189:Retrospective Studies; D013815:Thermodilution; D014947:Wounds and Injuries / Q000503:physiopathology*