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Non-invasive cardiac output determination by two-dimensional independent Doppler during and after cardiac surgery

Karsten Knobloch1, Artur Lichtenberg, Michael Winterhalter

  • 1Department of Trauma Surgery, Medical School Hannover, Hannover, Germany. kknobi@yahoo.com

The Annals of Thoracic Surgery
|September 27, 2005
PubMed

Insights

A novel noninvasive Doppler technique accurately measures cardiac output (CO) in postcardiac surgery patients. This method, using the Ultrasonic Cardiac Output Monitoring (USCOM) device, offers a safe alternative to invasive monitoring.

Area of Science:

  • Cardiology
  • Critical Care Medicine
  • Medical Devices

Background:

  • Accurate cardiac output (CO) monitoring is crucial in postcardiac surgery intensive care units (ICUs).
  • Invasive methods, such as Swan-Ganz catheterization, carry potential complications.
  • Noninvasive techniques are sought to provide reliable CO and stroke volume (SV) data.

Purpose of the Study:

  • To compare noninvasive CO measurements using a novel Doppler technique (USCOM) with invasive CO measurements.
  • To evaluate the agreement and correlation between the USCOM device and the Swan-Ganz catheter in postcardiac surgery patients.

Main Methods:

  • Prospective study of 36 patients undergoing coronary revascularization.
  • Paired measurements of CO and SV using the noninvasive USCOM device and invasive Swan-Ganz catheter.
  • Intraoperative direct insonation of the right ventricular outflow tract for comparison.

Main Results:

  • Excellent agreement between noninvasive (USCOM) and invasive (Swan-Ganz) CO measurements (r = 0.870; p < 0.01).
  • Mean difference between methods was minimal (-0.23 +/- 1.01 L/min) across a wide CO range.
  • Central venous saturation correlated significantly with both noninvasive and invasive CO measurements.

Conclusions:

  • The USCOM device provides accurate, noninvasive, beat-to-beat CO and SV measurements in postcardiac surgery patients.
  • USCOM offers a safe alternative to invasive right heart catheterization, avoiding associated complications.
  • The findings support the clinical utility of USCOM for hemodynamic monitoring in this patient population.
Abstract

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