title: Evaluation of invasive and noninvasive hemodynamic monitoring in trauma patients.
abstract: OBJECTIVE
  The aim of this study was to compare a recently developed and improved noninvasive hemodynamic monitoring system with the conventional invasive monitoring by pulmonary artery catheterization (PAC) in acute emergency trauma patients.
  
  
  METHODS
  In a large, university-run, inner city public hospital, we monitored 993 trauma patients noninvasively; 262 of these were simultaneously monitored with both noninvasive hemodynamic and invasive PAC monitoring. The noninvasive monitoring was begun shortly after admission to the emergency department and the invasive PAC monitoring was started in the operating room, or as soon as the patient arrived in the intensive care unit. Noninvasive monitoring included cardiac index (CI) by the IQ or Physio Flow bioimpedance device, together with mean arterial blood pressure, heart rate, pulse oximetry (SapO2), transcutaneous oxygen (PtcO2), and carbon dioxide (PtcCO2) tensions. We compared CI by simultaneous measurements with both invasive and noninvasive methods 907 times in 262 patients.
  
  
  RESULTS
  The CI by thermodilution (CItd) correlated well with simultaneous measurements with the bioimpedance (CIbi), r2 = 0.915, r2 = 0.84, p < 0.001. The bias and precision of simultaneous measurements was -0.070 +/- 0.47 L/min/m2; agreement was considered satisfactory. In the initial resuscitation period of both monitoring systems, the CI, mean arterial blood pressure, SapO2, and tissue perfusion (reflected by invasive DO2 and VO2, and by noninvasive PtcO2/FiO2 ratio) were higher in survivors than in nonsurvivors, whereas heart rate values were higher in the nonsurvivors. We concluded that noninvasive hemodynamic monitoring provided a feasible, safe, inexpensive, accurate, continuous, on-line real-time graphic displays that are equivalent to the essential features of invasive pulmonary artery catheter monitoring.
authors.affiliation: Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA. wcshoemaker00@hotmail.com
authors.forename: William C
authors.initials: WC
authors.lastname: Shoemaker
authors.forename: Charles C J
authors.initials: CC
authors.lastname: Wo
authors.forename: Li-Chien
authors.initials: LC
authors.lastname: Chien
authors.forename: Kevin
authors.initials: K
authors.lastname: Lu
authors.forename: Nasrollah
authors.initials: N
authors.lastname: Ahmadpour
authors.forename: Howard
authors.initials: H
authors.lastname: Belzberg
authors.forename: Demetrios
authors.initials: D
authors.lastname: Demetriades
mesh_terms: D000328:Adult; D001794:Blood Pressure; D002302:Cardiac Output; D017097:Electric Impedance; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010101:Oxygen Consumption; D016019:Survival Analysis; D013997:Time Factors; D014947:Wounds and Injuries / Q000145:classification* / Q000401:mortality / Q000503:physiopathology