title: Clinical evaluation of USCOM ultrasonic cardiac output monitor in cardiac surgical patients in intensive care unit.
abstract: BACKGROUND
  The USCOM ultrasonic cardiac output monitor (USCOM Pty Ltd, Coffs Harbour, NSW, Australia) is a non-invasive device that determines cardiac output by continuous-wave Doppler ultrasound. The aim of this study was to evaluate the accuracy of the USCOM device compared with the thermodilution technique in intensive care patients who had just undergone cardiac surgery.
  
  
  METHODS
  We conducted a prospective study in the 18-bed intensive care unit of a 600-bed tertiary referral hospital. Twenty-four mechanically ventilated patients were studied immediately following cardiac surgery. We evaluated the USCOM monitor by comparing its output with paired measurements obtained by the standard thermodilution technique using a pulmonary artery catheter.
  
  
  RESULTS
  Forty paired measurements were obtained in 22 patients. We were unable to obtain an acceptable signal in the remaining two patients. Comparison of the two techniques showed a bias of 0.18 and limits of agreement of -1.43 to 1.78. The agreement may not be as good between techniques at higher cardiac output values.
  
  
  CONCLUSIONS
  The USCOM monitor has a place in intensive care monitoring. It is accurate, rapid, safe, well-tolerated, non-invasive and cost-effective. The learning curve for skill acquisition is very short. However, during the learning phase the USCOM monitor measurements are rather 'operator dependent'. Its suitability for use in high and low cardiac output states requires further validation.
authors.affiliation: Department of Intensive Care, Sir Charles Gairdner Hospital and Pharmacology Unit, School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.
authors.forename: H L
authors.initials: HL
authors.lastname: Tan
authors.forename: M
authors.initials: M
authors.lastname: Pinder
authors.forename: R
authors.initials: R
authors.lastname: Parsons
authors.forename: B
authors.initials: B
authors.lastname: Roberts
authors.forename: P V
authors.initials: PV
authors.lastname: van Heerden
mesh_terms: D000328:Adult; D000368:Aged; D002302:Cardiac Output; D006348:Cardiac Surgical Procedures; D003422:Critical Care / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D011182:Postoperative Care / Q000295:instrumentation* / Q000379:methods; D011446:Prospective Studies; D015203:Reproducibility of Results; D013815:Thermodilution; D018608:Ultrasonography, Doppler / Q000295:instrumentation