Evaluation of the Paratrend 7 intravascular blood gas monitor during cardiac surgery: comparison with the C4000 in-line blood gas monitor during cardiopulmonary bypass.
OBJECTIVE
To evaluate the performance of the Paratrend 7 intravascular blood gas monitor (Biomedical Sensors, High Wycombe, UK, Ltd) during cardiac surgery and compare it with that of an in-line blood gas monitor placed in the arterial limb of an extracorporeal circuit during cardiopulmonary bypass.


METHODS
A prospective study. Consecutive patient enrolment.


METHODS
In the cardiac surgical intensive care units at a tertiary referral center.


METHODS
Insertion of the Paratrend 7 intravascular sensor through the radial arterial catheter after induction of anesthesia.


RESULTS
Simultaneous measurements of pH, PCO2, and PO2 were made from the sensor and the blood gas analyzer, and the bias and precision were calculated on all the measured parameters. The bias and precision of the intravascular sensor during bypass for pH, PCO2, and PO2 were 0.01 and 0.06 pH units, 0.5 and 2.5 mmHg (2% and 8%), and 3 and 45 torr (0.5% and 14%), respectively. The bias and precision for the prebypass and the postbypass phases were comparable. The bias and precision of the extracorporeal monitor for pH, PCO2, and PO2 were 0.04 and 0.1 pH units, -0.3 and 4 mmHg (-1% and 15%) and 8 and 48 mmHg (4 and 18%), respectively. There were no instances of any complications attributable to the intravascular sensor.


CONCLUSIONS
The intravascular sensor used in this study functioned well during cardiopulmonary bypass and the postbypass phase. The performance of the intravascular sensor was better than the in-line blood gas monitor during cardiopulmonary bypass.
Venkatesh
B
B
University Department of Anaesthesia and Intensive Care, Queen Elizabeth Hospital, University of Birmingham, UK.
Clutton-Brock
T H
TH
Hendry
S P
SP
D000328:Adult; D000368:Aged; D015982:Bias; D001769:Blood; D001784:Blood Gas Analysis / Q000295:instrumentation* / Q000706:statistics & numerical data; D001831:Body Temperature; D002245:Carbon Dioxide / Q000097:blood; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass / Q000295:instrumentation; D002406:Catheterization, Peripheral / Q000295:instrumentation; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D005112:Extracorporeal Circulation / Q000295:instrumentation; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation* / Q000706:statistics & numerical data; D010100:Oxygen / Q000097:blood; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D002245:Carbon Dioxide; D010100:Oxygen