Non-invasive Cardiac Output by Transthoracic Electrical Bioimpedence in Post-cardiac Surgery Patients: Comparison with Thermodilution Method

  • Arunodaya R. Gujjar
  • K. Muralidhar
  • Sanjay Banakal
  • Ratan Gupta
  • Talakad N. Sathyaprabha
  • P. S. Jairaj



Thoracic electrical bioimpedance (TEB) cardiac output (CO) is being explored increasingly as a non-invasive alternative to the pulmonary artery catheter (PAC). This study compared TEB-CO measured using a new instrument – NICOMON (Larsen & Toubro Ltd. India) with thermodilution (Td) CO in post-cardiac surgery patients.


Postoperative cardiac surgical patients requiring a PAC for their management were studied. TEB-CO was measured by passing a 4 mA RMS alternating current across the chest and measuring the analog bioimpedence across the thorax. Kubicek equation was used to estimate TEB-CO. Td-CO was measured using a PAC. Bland-Altman analysis was used to compare paired data.


One hundred and ninety-seven pairs of CO measurements were made by the two methods among 35 patients. Mean TEB-CO was 5.15 ± 1.27 l/min and mean Td-CO was 5.22 ± 1.28 l/min. Pearson correlation coefficient (r) for these measurements was 0.856 (P < 0.01), with bias −0.0651 l and precision: ±1.37 l/min. The percentage error of measurement of this precision was 26.44%. Cardiac index also correlated among the two methods (r = 0.789; P = 0.01).


Thoracic electrical bioimpedance cardiac output compares favorably with thermodilution method among post-cardiac surgery patients. Further studies are indi- cated with this instrument to validate its efficacy in various clinical situations and utility in monitoring hemodynamic interventions.


Thoracic electrical bioimpedance Bioimpedance cardiac output Cardiac output Noninvasive cardiac output 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Shah MR, Hasselblad V, Stevenson LW, Binanay C, O’Connor CM, Sopko G, Califf RM. Impacts of the pulmonary artery catheter in critically Ill patients: meta-analysis of randomized trials. J Am Med Assoc 2005; 294: 1634–1670CrossRefGoogle Scholar
  2. 2.
    Binanay C, Califf RM, Hasselblad V, O’Connor CM, Shah MR, Sopko G, Stevenson LW, Francis GS, Leier CV, Miller LW. ESCAPE investigators and ESCAPE Study Coordinators. Evaluation study of congestive heart failure and pulmonary artery catheterization effectiveness: the ESCAPE trial. J Am Med Assoc 2005; 294: 1625–1633Google Scholar
  3. 3.
    Barin E, Dinesh G, Haryadi, Segel I, Schookin, Dwayne R, Westenkow, et al. Evaluation of a thoracic bioimpedance cardiac output monitor during cardiac catheterization. Crit Care Med 2000; 28: 698–702PubMedCrossRefGoogle Scholar
  4. 4.
    Shoemaker WC, Belzberg H, Wo CCJ, et al. Multicenter study of noninvasive monitoring systems as alternatives to invasive monitoring of acutely ill emergency patients. Chest 1998; 114: 1643–1652PubMedCrossRefGoogle Scholar
  5. 5.
    Appel PL, Kram HB, Mackabee J, Fleming AW, Shoemaker WC. Comparison of measurements of cardiac output by bioimpedence and thermodilution in severely ill surgical patients. Crit Care Med 1986; 14: 933–935PubMedCrossRefGoogle Scholar
  6. 6.
    Zeigler D, Grotti L, Krucke G. Comparison of cardiac output measurements by TEB vs intermittent bolus thermodilution in mechanical ventilated patients. Chest 1999; 116: 281S (Abstract)Google Scholar
  7. 7.
    Hirschl MM, Kittler H, Woisetschläger C, Siostrzonek P, Staudinger T, Kofler J, Oschatz E, Bur A, Gwechenberger M, Laggner AN. Simultaneous comparison of thoracic bioimpedance and arterial pulse waveform-derived cardiac output with thermodilution measurement. Crit Care Med 2000; 28: 1798–1802PubMedCrossRefGoogle Scholar
  8. 8.
    Fuller HD. The validity of cardiac output measurements by thoracic impedance: A meta-analysis. Clin Invest Med 1992; 15: 103–112PubMedGoogle Scholar
  9. 9.
    Raaijmakers E, Faes TJC, Scholten RJPM, et al. A meta-analysis of three decades of validating thoracic impedance cardiography. Crit Care Med 1999; 27: 1203–1213PubMedCrossRefGoogle Scholar
  10. 10.
    Jindal GD, Ananthakrishnan TS, Kataria SK, Deshpande AK. An introduction to impedance cardio-vasography. Bhabha Atomic Research Center publication, Mumbai, India, 2001Google Scholar
  11. 11.
    Kubicek W, Patterson RP, et al. Impedance cardiography as a non-invasive method of monitoring cardiac functions and other parameters of the cardiovascular system. Annals of New York Academy of Sciences 1970: 724–732Google Scholar
  12. 12.
    Bland JM, Altmal DG. Comparing methods of measurement: why plotting difference against standard method is misleading. Lancet 1995; 346: 1085–1087PubMedCrossRefGoogle Scholar
  13. 13.
    Critchley LA, Critchley JA. A meta-analysis of studies using bias and precision statistics to compare cardiac output measurement techniques. J Clin Monit Comput 1999; 15: 85–91PubMedCrossRefGoogle Scholar
  14. 14.
    Van De Water JM, Miller TW, Vogel RL, Mount BE, Dalton ML. Impedance cardiography: the next vital sign technology? Chest 2003; 123: 2028–2033CrossRefGoogle Scholar
  15. 15.
    Thomas AN, Ryan J, Doran BR, Pollard BJ. Bioimpedance versus thermodilution cardiac output measurement: the Bomed NCCOM3 after coronary bypass surgery. Intensive Care Med. 1991; 17: 383–386PubMedCrossRefGoogle Scholar
  16. 16.
    Koobi T, Kaukinen S, Turjanmaa VM. Cardiac output can be reliably measured noninvasively after coronary artery bypass grafting operation. Crit Care Med 1999; 27: 2206–2211PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Arunodaya R. Gujjar
    • 1
  • K. Muralidhar
    • 3
  • Sanjay Banakal
    • 3
  • Ratan Gupta
    • 4
  • Talakad N. Sathyaprabha
    • 2
  • P. S. Jairaj
    • 5
  1. 1.Department of NeurologyNational Institute of Mental Health & NeurosciencesBangaloreIndia
  2. 2.Department of NeurophysiologyNational Institute of Mental Health & NeurosciencesBangaloreIndia
  3. 3.Department of AnaesthesiologyNarayana Hrudayalaya Institute of Cardiac SciencesBangaloreIndia
  4. 4.Department of Intensive CareNarayana Hrudayalaya Institute of Cardiac SciencesBangaloreIndia
  5. 5.Department of Cardiac SurgeryNarayana Hrudayalaya Institute of Cardiac SciencesBangaloreIndia

Personalised recommendations