A comparison of a continuous noninvasive arterial pressure (CNAP) monitor with an invasive arterial blood pressure monitor in the cardiac surgical ICU Full Text
Annals of Cardiac Anaesthesia, 07/18/2012
Jagadeesh AM et al. – The authors conclude continuous noninvasive arterial blood pressure (CNAP) is a reliable, noninvasive, continuous blood pressure monitor that provides real–time estimates of arterial pressure comparable to those generated by an invasive arterial catheter system. CNAP can be used as an alternative to invasive arterial blood pressure (IAP).Methods
- In a prospective study the authors compared the CNAP monitoring device with invasive arterial blood pressure (IAP) measurement in 30 patients in a cardiac surgical Intensive Care Unit (ICU).
- Patients were either mechanically ventilated or spontaneously breathing, with or without inotropes.
- CNAP was applied on two fingers of the hand contralateral to the IAP monitoring catheter.
- Systolic, diastolic and mean pressure data were recorded every minute for 2h simultaneously for both IAP and CNAP.
- Statistical analysis included construction of mountain plot and Bland Altman plots for assessing limits of agreement and bias (accuracy) calculation.
- Three thousand and six hundred pairs of data were analyzed.
- The CNAP systolic arterial pressure bias was 10.415mmHg and the CNAP diastolic arterial pressure bias was –5.3386mmHg; the mean arterial pressure (MAP) of CNAP was close to the MAP of IAP, with a bias of 0.03944mmHg.
- The Bland Altman plot showed a uniform distribution and a good agreement of all arterial blood pressure values between CNAP and IAP.
- Percentage within limits of agreement was 94.5%, 95.1% and 99.4% for systolic, diastolic and MAP.
- Calculated limits of agreement were –4.60 to 25.43,–13.38 to 2.70 and –5.95 to 6.03mmHg for systolic, diastolic and mean BP, respectively.
- The mountain plot showed similar results as the Bland Altman plots.